ENTO 311 Pests of Crops and stored grain and their management (Solved Practical Manual)

                                                                EXERCISE No. I

PESTS OF RICE

More than 100 insect species are associated with the rice crop at one stage or the other

and 20 of these are pests of major economic significance.

1.   Stem Borer:

A.   Yellow stem borer: Scirpophaga incertulas (Pyralidae: Lepidoptera)

F Distribution and Status: Afghanistan, Bangladesh, Burma, Cambodia, China, India, Sri Lanka and Indonesia.

F Host range: Rice

F Life history:

Female moth has bright yellowish brown fore wings with a black spot and a tuft of yellow anal hairs while male is smaller with pale yellow forewings without black spot.

Each female lays 170-200 eggs in a mass of 15-80 on the upper surface of leaf tips covered with buff-colored hairs. The egg period 6-9 days; larva pale yellow with dark brown head, swims in water and bores in to the stem near the node. The larva migrates to other tillers also. Larval period 20-45 days, pupation in white silken cocoon. Pupa dark brown in color, pupal period is 6-10 days.

F Nature of damage:

Larva feeds on the stem and causes drying of the central shoot known as “dead heart” in the young seedlings, and drying of the panicle in grown up plant called “white ear”. Damage ranges from 30-80%. Whitehead or dead panicles at reproductive stage (IRRI)

F ETL:

2 egg masses/ m2

10% dead hearts - Vegetative stage

2% white ear - Flowering stage

B.   Stripped stem borer: Chilo partellus (Pyralidae: Lepidoptera)

F Host range: Rice, sorghum, maize, sugarcane and wild grases.

F Life history: Each female lays 200 eggs. Larval period 15-26 days, pupation in stem, pupal period is 3-5 days, Life cycle completed in 6-7 weeks.

F Carryover: Pest hibernates as larva in stubbles in off season.

F Seasonal occurrence: Pest active from July to November.

v  Nature of damage: Larva feeds on the stem and causes drying of the central shoot known as “dead heart” in the young seedlings, and drying of the panicle in grown up plant called “white ear”. Damage ranges from 30-80%.

v  Management:

1.   Grow resistant varieties viz., Ratna, Jaya, TKM 6, IR 20 and IR 26, Sayasree, Saket, IET 3127, IET 2812, MTU 5849, PTB 12, PTB 20, PT 321, H 4.

2.   Clip the seedling tips before transplanting to eliminate egg masses and collect & destroy the egg masses in main field.

3.   Avoid close planting and continuous water stagnation at early stages.

4.   Clipping of the tips at time of transplant to destroy egg masses.

5.   Collect and destroy the dead hearts and white ears.

6.   Set up light traps to attract and kill the moths.

7.   Install sex pheromone traps to monitor and mass trap.

8.   Release the egg parasitoid, Trichogramma japonicum twice on 30 and 37 DAT @ 50000 parasitoids/ ha.

9.   Apply Bacillus thuringiensis var kurstaki and neem seed kernel extract in the combination of 2.5 g/L and 1% to reduce the oviposition by the stem borer.

10.  Apply carbofuran 3 G @ 25 kg or benfuracarb 3 G 33 kg or or Chlorantraniliprole 0.4 G 10 kg or fipronil 0.3 G 17-25 kg.

11.  Harvest the crop up to the ground level and disturb the stubbles with plough immediately after the harvest.

2.   Brown plant hopper: Nilaparvata lugens (Delphacidae: Hemiptera)

F Distribution and status: Orissa, Andhra Pradesh, Tamil Nadu, Karnataka, West Bengal, Maharashtra, Madhya Pradesh, Uttar Pradesh, Haryana and Punjab in India, South East Asia, China, Japan, Korea

F Host range: Rice, sugarcane, grasses

F Life history: - The brown plant hopper has a brown body and chestnut brown eyes. Adult measures about 4 - 4.5 mm in length capable of flying a long-distance drifting with the wind. Adults are of two forms viz., macropterous (long winged) and brachypterous (short winged). The female makes an incision in the leaf sheath and inserts 200-300 small eggs, egg period -6 days; nymphal period - 15 days and adult longevity 18-20 days.

F Nature of damage:

Nymphs and adults congregate at the base of the plant above the water level and suck the sap from the tillers. The affected plant dries up and gives a scorched appearance called “hopper burn”. Circular patches of drying and lodging of matured plants are typical symptoms caused by this pest. It is the vector of grassy stunt, ragged stunt and wilted stunt diseases.

F ETL: 8-10 Nos./hill or 20 Nos./hill when spider is present at 1 No./hill

v  Management

1.   Use resistant varieties like Aruna, Karnataka, Karthika, Krishnaveni, Makon, Abhey, Asha, Divya, Py 3, Co 42, Co 46, PTB 21, Jyoti (PTB 29) and PTB 33, Manasarowar, Bhadra, IET 7575, IET 6315, MTU 1249, R 650 - 1820, Shyraksha, Arvindar, kartik, bharatidasan, neela, uday, sonasali, vajram, chaitanya, nagarrjuna and chandana,

2.   Avoid close planting and provide 30 cm rogue spacing at every 2.5 m to reduce the pest incidence.

3.   Avoid use of excessive nitrogenous fertilizers.

4.   Control irrigation by intermittent draining.

5.   Set up light traps to monitor and control pest population.

6.   Release of natural enemies like wolf spider, Lycosa pseudoannulata and green mirid bug Cyrtorrhinus lividipennis.

7.   Avoid use of insecticides causing resurgence such as synthetic pyrethroids, methyl parathion, fenthion and quinalphos.

8.   Drain the water before the use of insecticides and direct the spray towards the base of the plants.

9.   Spray neem seed kernel extract 5% (25 kg/ha) (or) neem oil 2% (10 L/ha).

10.  Spray imidacloprid 17.8 SL 125 ml or buprofezin 25 SC 325 ml or or acephate 75 SP 625 g or or /ha.

3.   Paddy Jassids (Green leafhopper): Nephotettix virescens, N. nigropictus and N. Cincticeps (Cicadellidae: Hemiptera)

v  Distribution and status: India, South Japan to oriental region, west of south Africa, Phillippines, Formosa, Sri Lanka.

v  Host range: Rice, millets, grasses.

v  Life history: Adults green with black spot and black patch on wings, gravid female inserts 200-300 eggs in batches of 8-16 in midrib of leaf blade. Egg period 6-7 days, nymphs undergo five instars and become adult in 25 days. Adult longevity 20-30 days. The population normally increases from August onwards, reaches maximum during September - October and declines from November.

v  Nature of damage: Both nymphs and adults desap the leaves and cause “hopper burn” due to heavy infestation. Yellowing of leaves from tip downwards is the typical symptom caused by this pest. However, it is more important as a vector for rice tungro virus, rice yellow dwarf and transitory yellowing diseases.

v  ETL:

60 Nos. / 25 sweeping – Nursery

10 Nos. / hill - Flowering stage

5 Nos. / hill - Vegetative stage

2 Nos. / hill - Tungro endemic area

v  Management

1.   Use resistant varieties like IR 20, IR 50, CR 1009, Co 46, PTB 2, PTB 18, IET 7301, IET 7302, IET 7303 and Vani, Vikra marka, Lalit, Nidhi

2.   Nursery should not be raised near the lamp posts.

3.   Apply neem cake @ 12.5 kg/800 m2 nursery as basal dose.

4.   Apply carbofuran 3 G @ 3.5 kg or phorate 10 G @ 1.0 kg or quinalphos 25 EC 80 ml or endosulfan 35 EC 80 ml per 800 m2 nursery. Maintain the water level at 2.5 cm for 3 days after granular application.

5.   Spray any of the following insecticide in 500 L water/ha

F Acephate 75 SP 666-1000 g

F Imidacloprid 17.8 SL 100 -125 ml

F Endosulfan 35 EC 1000 ml

F Quinalphos 25 EC 1000 ml

4.   Paddy Grasshopper: Hieroglyphus banian (Acrididae: Orthoptera)

v  Life history: Adults are green, larger with transverse black lines on pronotum. It lays eggs in soil at a depth of 5 cm. Nymphal period is from 2.5 - 3.5 months

v  Nature of damage: The nymphs and adults cause enormous loss to the crop by chewing and cutting various plant portion viz., leaves, flowers and grains. They completely defoliate the plants leaving only the mid ribs and the plant growth is affected.

v  Management:

1.   Expose the eggs to be picked up by birds after ploughing and trimming the bunds

2.   Egg parasitoids Cacallus spp., Barycomus spp. and Seelio spp., should be encouraged.

3.   Dust the crop with 5-10% BHC (or) methyl parathion 2% or lindane 2 D 25-30 kg/ha (or) malathion 5 D 20 kg/ha

4.   Spray dichlorvos 76 EC 500 ml/ha (or) malathion 50 EC 2.5 lit/ha.

v  Integrated Pest Management in Paddy

A.   Cultural method

1.   Remove / destroy stubbles after harvest and keep the field free from weeds.

2.   Trim and plaster the bunds of rice field to expose the eggs of grasshoppers and to eliminate the bug breeding in grasses.

3.   Form the bunds narrow and short to reduce the damage by rodents.

4.   Use resistant varieties wherever available.

5.   Provide effective drainage wherever there is problem of BPH.

6.   Clip the tip of seedlings before transplanting to prevent the carry-over of egg masses of rice yellow stem borer from nursery to main field.

7.   Organise synchronized planting wherever possible.

8.   Leave 30 cm rogue space at every 2.5 m to reduce damage by BPH and rodents.

9.   Avoid use of excessive nitrogenous fertilizers.

10.    Use irrigation water judiciously (Alternative wetting and drying reduce BPH and case worm).

11.    Remove the egg masses of stem borer in the main field.

B.   Mechanical methods

1.   Dig out the rat burrows and destroy the rats and young ones at the beginning of the season.

2.   Set up light traps to monitor and control pests.

3.   Set up-bow traps to kill rodents.

C.   Biological methods

1.   Release Trichogramma japonicum twice on 30 and 37 DAT @ 5 cc/ha/release against stem borer.

2.   Release Trichogramma chilonis on 37, 44 and 51 DAT (thrice) @ 5 cc/ha/release against leaf folder.

3.   Release of Platygaster oryzae parasitized galls @ 1 per 10 m2 in the mainfield on DAT against gall midge.

4.   Set up owl perches to reduce rat damage.

D.  Plant products

1.   Spray neem seed kernel extract 5% (25 kg/ha), neem oil 3% (15 lit/ha) to control brown planthopper.

2.   Spray botanicals viz., NSKE, Vitex negundo (Notchi), Prosopis juliflora and Ipomoea carnea leaf extract 5% to control earhead bug and black bug.

E.   Chemical methods

1.   In BPH prone area / season avoid use of synthetic pyrethroids, methyl parathion and quinalphos and use recommended chemical at recommended doses.

2.   Use insecticides based on ETL.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

EXERCISE No. 2

PESTS OF SORGHUM

More than 150 species of insects have been reported to damage sorghum. However over a dozen species are very serious and constitute a major constraint in sorghum production. Shoot fly, stem borers, shoot and ear head bug and aphids are serious pests that bring reduction in the yield.

1.   Sorghum Stem borer: Chilo partellus (Pyralidae: Lepidoptera)

v  Distribution and status: India, Pakistan, SriLanka, Indonesia, Iraq, Japan, Uganda, Taiwan, Sudan, Nepal, Bangladesh and Thailand.

v  Host range: Maize, sugarcane, bajra, rice, finger millet, etc.

v  Life history: The adult moth is medium in size and straw coloured. It lays about 300 scalelike flat oval eggs in batches on the under surface of leaf near the midrib. The incubation period is 2-5 days. The larva is yellowish brown with a brown head and the prothoracic shield measures about 25 mm long. The larval period is 28 - 50 days with seven instars. It pupates inside the stem and emerges in 7-10 days through the larvae's entry holesas as adult. The total life cycle is completed in 30 to 40 days.

v  Carry over: Pest hibernates as larva in stubbles.

v  Seasonal occurrence: July to November

v  Nature of damage: It infests the crop a month after sowing and the damage persists upto emergence of ear heads. Central shoot withering leading to “dead heart” is the typical damage symptom. Bore holes are visible on the stem near the nodes. Young larva crawls and feeds on tender folded leaves causing typical “shot hole” symptom. Affected parts of stem may show internally tunneling caterpillars.

v  Bore holes and tunneling by caterpillars

v  ETL: 10% dead heart

v  Management:

1.   The stubbles should be ploughed up during winter and burnt to destroy the hibernating larvae.

2.   Grow resistant cultivars like E 302, E 303, IS 2205, ICSV 700

3.   Dead hearts should be pulled out and used as fodder or buried in manure pits.

4.   Sow Dolichos as an intercrop in the ratio of 4:1 to minimise the stem borer damage.

5.   Set up light trap till midnight to attract and kill the stem borer moths.

6.   Bio-control agents viz.,Trichogramma chilonis (egg parasitoids) minutum, Bracon chinensis and Apanteles flavipes, (larval parasitoids) should be encouraged.

7.   Mix any one of the following insecticides with sand to make up the total quantity of 50 kg and apply in the leaf whorls. Phorate - 10 G 8 kg, carbofuran 3 G 17 kg, endosulfan 4D 25 kg or spray endosulfan 35 EC 750 ml (or) carbaryl 50 WP 1 kg (500 L spray fluid/ha).

2.   Sorghum Shootfly: Atherigona soccata (Muscidae/ Anthomyidae : Diptera)

v  Distribution and status: Maharashtra, Andhra Pradesh, Tamil Nadu and Karnataka

v  Host range: Maize, ragi, bajra, rice, wheat and grasses

v  Life history: Adult, a whitish grey female fly lays white, cigar-shaped eggs on the lower surface of leaf blades mostly during morning hours. The egg is white, cylindrical, distal end somewhat flattened. The incubation period varies from 2-3 days. Maggot is dirty white and apodous. Mature larvae are yellow and about 6 mm long. The larval period is 8-10 days and has four larval instars. It pupates at the base of the stem or in soil for 8-10 days. The life cycle is completed in 17-21 days.

v  Carry over: Pest over winters in adult stage on grasses.

v  Seasonal occurrence: July to October.

v  Nature of damage: The maggot on hatching migrates to the upper surface of leaf and enters between the leaf sheath and stem. After reaching the soil level, the maggot bores inside the stem and cuts the growing point resulting in “dead heart” symptom. The infested plant produces side tillers and pland gets bushy apperance. The attack is more severe during summer than kharif season

v  ETL: 10% dead hearts or 1 egg / plant

v  Management:

1.   Use resistant varieties like Co-1, CSH 15R, Maldandi and Hagari, M35-1, Swati, SPV 491, IS - 18551, 5566, 5285, 5613, ICSV 700, ICSV 705, Phule Yashoda, CSH 7, CSH 8

2.   Sow sorghum immediately at the onset of monsoon rains to minimise shootfly damage.

3.   Use higher seed rate (12.5 kg/ha) and remove the shoot fly damaged seedlings at the time of thinning or raise nursery and transplant only healthy seedlings.

4.   Pull out and destroy plants showing dead hearts at the time of thinning.

5.   Set up hanging type of plastic fishmeal trap @ 12/ha till the crop is 30 days old.

6.   Treat 100 kg seeds with chlorpyriphos 20 EC 400 ml or quinalphos 25 EC 400 ml or imidacloprid 48 FS 1.2 L or imidacloprid 70 WS 1.0 kg or thiomethoxam 30 FS 1.0 L

7.   Granular application of phorate 10 G or carbofuran 3 G to the furrow at the time of sowing at 2.5 kg a.i./ha.

8.   Spray endosulfan 35 EC @18 ml, dimethoate 30 EC @ 12 ml and methyl demeton 25 EC @12 ml for an area of 120 m2 nursery.

9.   Spray any one of the following insecticides in the mainfield - endosulfan 35 EC 500 ml, dimethoate 30 EC 500 ml (250 L of spray fluid/ha).

3.   Sorghum midge fly: Contarinia sorghicola (Cecidomyiidae: Diptera)

v  Distribution and status: India, Pakistan, Bangladesh, West Iran, Sri Lanka, Sudan, Java, Africa, South East Asia, South China, South America, West Indies, USA and Italy.

v  Hosts: Wild grasses species as Sudan grass, Johnson grass, Pankanis etc.

v  Life history: The adult fly is small, fragile with a bright orange abdomen and a pair of transparent wings. It lays eggs singly in developing florets resulting in pollen shedding. A female lays about 30-35 eggs at the rate of 6-10 in each floret. The incubation period is 3-4 days. The maggot has four instars with duration of 8-10 days. Larvae are colorless, but, when fully grown, they are dark orange. Larval period 9 - 11 days. The larval stage undergoes diapause in a cocoon during December – January within a spikelet. Pupates beneath the glume. The pupal period 3 days. When the adult emerges the white pupal skin remains at the tip of the spikelet. A generation is completed in 14-16 days. The insect's rapid developmental cycle permits 9-12 generations.

v  Carry over: Pest hibernates as larva in soil debris or in husk or kutar..

v  Seasonal occurrence: August to October.

v  Nature of damage: A maggot feeds on the developing grains and pupates there. White pupal cases protruding out from the grains and chaffy grains with holes are the Nature of damage.

v  Management:

1.   Adopt zonal system: of sowing one variety in a group of 8-10 villages as early as possible within a week. If possible hybrid variety should be sown from 20^th to 30th July.

2.   Grow resistant cultivars like DJ 6541, AF 28, ICSV 197, ICSV 745, ICSV 88032.

3.   Conserve larval parasitoids - Apanteles sp., Eupelones popa; Larval and pupal parasitoid - Tetrastichus spp.; Predators – Orius albidipennis; Tapinoma indicum.

4.   Give first application at nearly 90% earhead emergence and repeat after 4 or 5 days. The insecticides recommended are spray endosulfan 35 EC 1.0 L (or) malathion 50 EC 1.0 L (or) carbaryl 50 WP 2 kg/ha or endosulfan 4 D or malathion 5 D or carbaryl 10 D or quinalphos 1.5 D at 25 kg/ha .

4.   Aphids: Rhopalosiphum maidis, Aphis sacchari (Aphididae:Hemiptera)

v  Distribution and status: All sorghum-growing areas of the world.

v  Host range: Sorghum, maize, ragi

v  Life history:

Rhopalosiphum maidis:

The aphid is dark bluish-green and somewhat ovate. It is 2 mm long, with

black legs, cornicles, and antennae. Winged and wingless forms occur. Females give birth to living young without mating and a generation requires only a week or so. The adult is yellow coloured with dark green legs.

Aphis sacchari:

The sugarcane aphid is yellow to buff. Numbers increase rapidly during dry spells or at the end of the rainy season. The female of the wingless form deposits 60- 100 nymphs within its reproductive period of 13-20 days. The winged form produces slightly fewer nymphs. The life cycle is completed in 5.5-7.0 days during the dry season.

v  Nature of damage: Colonies of aphids are seen in central leaf whorl, stems, or in panicles. The nymph and adults suck the plant juice. This frequently causes yellowish mottling of the leaves and marginal leaf necrosis. The aphid produces an abundance of honeydew on which molds grow. In panicles, honeydew may hinder harvesting. The aphid also transmits maize dwarf mosaic virus.

v  Management:

Spray the base of attacked plants with a contact (or) systemic insecticide like dimethoate 30 EC or methyl demeton 25 EC 500 ml in 500 L of water

v  Integrated Pest Management in Sorghum

A.   Cultural methods:

1.   Complete the sowing of sorghum in a short time to avoid continuous flowering, which favours grain midge and earhead bug multiplication.

2.   Sow Sorghum: lablab/cowpea (4:1) as an intercrop to minimize stem borer damage.

3.   Take up early sowing of sorghum immediately after the receipt of South West or North East Monsoon to minimize the shoot fly incidence.

4.   Use increased seed rate upto 12.5 kg per hectare and remove the shoot fly damaged seedlings at the time of thinning in case of direct sowing or raise nursery and transplant only healthy seedlings.

5.   Plough soon after the harvest, remove and destroy the stubbles.

B.   Mechanical method:

1.   Set up light traps till mid night to monitor, attract and kill adults of stemborer, grain midge and ear head caterpillars.

2.   Set up sex pheromone trap at 12/ha to attract male moths Helicoverpa sp. From flowering to grain hardening.

3.   Set up the TNAU low-cost fishmeal traps @ 12/ha till the crop is 30 days old.

C.   Biological methods:

1.   Take up two applications of NPV at 10 days interval at 250 LE/ha along with crude sugar 2.5 kg + cotton seed kernel powder 250 g on the ear heads to reduce the larval population of Helicoverpa sp.

D.  Chemical methods:

1.   Use seeds pelleted with insecticides.

2.   Arpocarb fishmeal formulation is more effective in attracting the shoot fly adults especially the females.

E.   Preparation of Arpocarb fishmeal:

Fishmeal powder is to be sprayed first with 2% starch dissolved in hot water as a sticking agent. The insecticide Arpocarb should then be sprayed at 50 ml/kg of fishmeal powder. The resultant mixture is shade dried and can be used at 50 g/trap. The formulated product should be moistened well before placing in the trap. The formulation can be changed once in 10-14 days depending upon the smell.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

EXERCISE No. 3

PESTS OF GROUNDNUT

1.   Groundnut Leaf roller/ Groundnut Leaf miner: Aproaeroma modicella (Gelechiidae: Lepidoptera)

v  Distribution and status: India, Pakistan, Sri Lanka, Burma and South Africa.

v  Host range: Groundnut, soybean and redgram.

v  Life history: Adult is dark brown with a white spot on the coastal margin of each forewing. The small hind wings are covered by fringe of minute hair. Adults are found briskly whirling around the plants in field and lay shiny transparent eggs singly on the under surface of leaflets. A female moth lays 150-200 eggs that hatch in 2-3 days. The larvae are pale brown. Fully grown larva measures 6-8 mm. The larval period is 4-17 days. They pupate in white silken cocoons within webbed leaflets and the pupae are reddish brown. The pupal period is 5-7 days. Adult longevity is 5-6 days. Life cycle is completed in 20-25 days. They cause severe damage from September to November to the rainfed crop and during March & April to irrigated crop.

v  Nature of damage: It prefers rainfed crop and bunch varieties. Young newly hatched green caterpillar mines into the leaflets and feed on green tissues resulting in brownish dried up patches. Later instars caterpillars fold the leaves together and feed on the green tissues by remaining inside. Severely infested crop presents a burnt up appearance. Caterpillars (or) pupae can be seen inside the mines and folded leaflets. It also attacks red gram and soybean.

v  ETL: 1 larva per meter row or five or more active larvae per plant are found up to 30 days after seedling emergence (DAE), 10 larvae per plant at 50 DAE and 15 larvae per plant at 75 DAE or later.

v  Management:

1.   Grow resistant cultivars like ICGV 86031, ICGS 156 (M 13), FDRS 10, ICG 57, 156, 541, 7016, 7404, 9883.

2.   Sow groundnut early and synchronously in rainy and rabi season.

3.   Intercrop groundnut with pearl millet @ 4:1 ratio.

4.   Set up light traps between 8 and 11 PM at ground level.

5.   Mulch the soil with straw within 10 days after germination wherever possible.

6.   Avoid water stress in irrigated crop to avoid the pest infestation.

7.   Maintain the fields and bunds free from weeds.

8.   Apply either endosulfan 4D or carbaryl 10 D at 25 kg/ha when the pest crosses ETL.

9.   Spray any one of the following insecticides - endosulfan 35 EC 750 ml/ha, dichlorovos 76 SC 625 ml/ha, quinolphos 25 EC 750 ml/ha, lambda cyhalothrin 5 EC 200-300 ml in 375 L of water.

2.   Groundnut Thrips: Scirtothrips dorsalis (Thripidae: Thysanoptera)

v  Economoic Impotance: Responsible for transmittind “Tomato Spotted Wilt Virus” and cause “Bud Necrosis” disease. Losses may extend upto 80%.

v  Life history: Nymphs and adults dark coloured with fringed wings. Female thrips lay 40-50 eggs inside the tissues of leaves and shoot. Egg period 5 days, nymphal period 7-10 days and adult period is 25-30 days. There are several overlapping generations.

v  Nature of damage:

Nymphs and adults suck sap from the surface of the leaflets. This results in white patches on the upper and necrotic patches on the lower surface of the leaves. It consists of distortions of the young leaf lets and patchy areas of necrotic tissue that puncture and split as the leaflets grow. Injury is normally seen in seedlings.

v  Management:

1.   Intercrop lab lab with groundnut 1:4 ratio

2.   Spray methyl demeton 25 EC 500 ml or dimethoate 30 EC 500 ml/ ha.

3.   Groundnut Pod Sucking bug: Elasmolomus sordidus (Lygaeidae: Hemiptera)

v  Life history: The adult is dark brown, approximately 10 mm long and 2 mm wide. In the field, the females lay their eggs singly in the soil or on groundnut haulms. But in storage eggs are laid loosely among the groundnuts. A female bug may lay upto 105 eggs. The egg period is 4-5 days. The first instar nymphs have a bright red abdomen, later instar become progressively darker. Both nymphs and adults feed on kernels by piercing the pods with their rostrum. The nymphal period is 23-29 days. Since it is nocturnal in habit, it hides under weeds, cracks and crevices in soil and debris during day time.

v  Nature of damage:

It is a serious pest at pod maturity stage, pod harvesting stage and harvested produce in the threshing floor. Both nymphs and adults suck the sap from the pod in the field and produce at threshing floor. Freshly harvested pods have shrivelled kernels become rancid and give bitter taste. The oil content and germination % of infested seeds are also adversely affected.

v  Management:

1.   Set up light traps to attract and kill the bugs.

2.   Keep the crop refuse in the field along irrigation channel to attract the bugs which can be killed by dusting.

3.   Dust the groundnut stored in the gunny bugs with malathion 4D or spray 0.05% malathion.

4.   White grub : Holotrichia consanguinea (Melalonthidae: Coleoptera)

v  Life history: The dark brown adult beetles reenter the soil to hide and lay eggs. Female lays 20 -80 white, roundish eggs in clusters. Egg period 9 - 11 days. Grubs are white and translucent. Pupates in soil and remain as pupae until the following year. The adult beetles emerge with the first monsoon showers.

v  Nature of damage:

Grubs feed on nodules and fine rootlets partially and also girdle the main root due to this type of damage. Groundnut having tap root system are mostly susceptible to the attack. Growth of plant is retarded and finally plants wilt or die.

v  Management:

1.   Plough deep at the time of land preparation to expose grub and kill.

2.   Adopt crop rotation with rice in irrigated endemic areas to bring down grub damage.

3.   Ensure adequate irrigation to irrigated groundnut in endemic areas since the grub attacks roots under inadequate soil moisture condition.

4.   Set up light traps or bonfires to attract and kill the adults on receipt of summer showers.

5.   Apply malathion or endosulfan or carbaryl dust @ 25 kg per ha in the soil prior to sowing during last ploughing.

6.   Repeat the same on 40 DAS and incorporate in the soil during earthing up.

7.   Seed treatment with chloropyripos 20ECor quinalphos 25EC @ 21/ 80 kg seeds in endemic pockets of white grub.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Exercise 4

PESTS OF MUSTARD

1.   Mustard Aphid: Lipaphis erysimi (Aphididae:Hemiptera)

v  Distribution and status: Distributed worldwide and is a serious pest

v  Host range: Cruciferous oilseeds like toria, sarson, raya, taramira and Brassica vegetables like cabbage, cauliflower, knol-khol,

v  Life history: They are louse like, pale-greenish insects abundant from December to March. During summer, it is believed to migrate to the hills. The pest breeds parthenogenetically and the females give birth to 26-133 nymphs. They grow very fast and are full-fed in 7-10 days. About 45 generations are completed in a year. Cloudy and cold weather (20°C or below) is very favourable for the multiplication of this pest. The winged forms are produced in autumn and spring, and they spread from field to field and from locality to locality.

v  Nature of damage: Both the nymphs and adults suck cell-sap from leaves, stems, inflorescence or the developing pods. Vitality of plants is greatly reduced. The leaves acquire a curly appearance, the flowers fail to form pods and the developing pods do not produce healthy seeds. The yield of an infested crop is reduced to one-fourth or one-fifth.

v  Management:

1.   Sow the crop early wherever possible, preferably up to third week of October.

2.   Apply recommended dose of fertilizers.

3.   Apply anyone of the following insecticides when the population of the pest reaches 50-60 aphids per 10 cm terminal portion of the central shoot or when an average of 0.5-l.0 cm terminal portion of central shoot is covered by aphids or when plants infested by aphids reach 40-50 per cent Foliar sprays - 625 -1000 ml of oxydemton methyl 25 EC, dimethoate 30 EC, endosulfan 35 EC, quinalphos 25 EC, malathion 50 EC; 940-1500 ml of chiorpyriphos 20 EC in 600-1000 L of water per ha depending on the stage of the crop.

4.   Granular insecticides - 10 kg of phorate lO G, 33 kg of carbofuran 30 per ha followed by a light irrigation.

5.   Conserve parasitoids Ischiodon scutellaris (Fabricius), Diaeretiella rapae M'Intosh (Braconidae) and Lipolexis gracilis Forester (Aphididae), predators viz., Syrphus serarius (Wiedmann) (Syrphidae). Brinckochrysa scelestes (Banks) (Chrysopidae), Coccinella septempunctata Linnaeus, Menochilus sexmaculatus (Fabricius) (Coccinellidae) and entomopathogens viz., Entomophthora coronata and Cephalosporium aphidicola.

2.   Mustard Sawfly: Athalia lugens (Tenthredinidae: Hymenoptera)

v  Distribution and status: Widely distributed in Indonesia, Formosa, Myanmar and the Indian Sub-continent.

v  Host range: Mustard, toria (Brassica campestris), rapeseed, cabbage, cauliflower, knolkhol, turnip, radish, etc

v  Life history: Dark green larvae have 8 pairs of abdominal prolegs. There are five black stripes on the back, and the body has a wrinkled appearance. A full-grown larva measures 16-18 mm in length. The adults are small orange yellow insects with black markings on the body and have smoky wings with black veins. The mustard sawfly breeds from October to March and undergoes pupal diapause during summer. The adults emerge from these cocoons early in October. They live for 2-8 days and lay 30-35 eggs singly, in slits made with saw like ovipositors along the underside of the leaf margins. Egg period is 4-8 days and the larvae feed exposed in groups of 3-6 on the leaves during morning and evening. They remain hidden during the day time and, when disturbed, fall to the ground and feign death. There are 7 instars with a larval period of 16-35 days. Pupation is in water proof oval cocoons in soil and the pupal period is 11-31 clays. Lifecycle is completed in 31-34 days. It completes 2-3 generations from October to March.

v  Nature of damage: The grubs alone are destructive. They bite holes into leaves preferring the young growth and skeletonize the leaves completely. Sometimes, even the epidermis of the shoot is eaten up. Although the seedlings succumb; the older plants, when attacked, do not bear seed.

v  Management:

1.   Give first irrigation 3-4 weeks after sowing as it reduces the bug population significantly.

2.   Spray 1.0 L of malathion 50 EC or 625 ml of endosulfan 35 EC or quinalphos 25 EC in 500-600 L of water per ha once in October and again in March-April.

3.   Conserve larval parasitoid Perilissus cingulator Morby (Ichneumonidae) and the bacterium, Serratia marcescens Bizio (Enterobacteriaceae).

4.   Spray 250 ml of dimethoate 30 EC or monocrotophos 36 SL or 625 ml of chlorpyriphos 20 EC in 750 litres of water/ha and repeat the spray after 15 days, if necessary.

5.   Conserve parasitoid Aphidencyrtus aphidivorus and predator Brumoides suturalis

 

 

 

 

 

 

 

 

Exercise 5

PESTS OF SOYBEAN

1.   Stem fly: Ophiomyia phaseoli / Melanagromyza sojae (Agromyzidae: Diptera)

v  Host range: It is a major pest of blackgram, greengram and soybean. Incidence is more in rainy season.

v  Life history: Shiny bluish – black fly deposit eggs in punctures made by fly on young leaves. Pupation is at ground level within the stem. Adult fly exits through a thin semi-transparent window.

v  Nature of damage:

Young plants (less than 40 days) suffer more. Yellowish maggots bore into nearest vein, reach the stem through petiole, bore down the stem and feed on cortical layers and may extend to tap root resulting in the following symptoms

F Distinct tunnel of stem split open.

F Death of plant or branches.

v  Management:

ü  Seed treatment with imidacloprid 3 g/kg seed gives protection upto 30 days.

ü  Foliar spray with acephate 1.5g/l or dimethoate 2 ml/l or monocrotophos 1.6ml/l.

2.   Leaf eating caterpillar:Spodoptera exigua (Noctuidae: Lepidoptera)

The caterpillar causes damage by feeding on leaves. For other details refer under millets.

3.   Soyabean leafminer: Aproaerema modicella/ Caloptilia soyella

v  Host range: Important pest of soybean also attacks groundnut and some leguminous weeds.

v  Life history:

Brownish grey moth lays white eggs singly on underside of leaves close to mid rib. Full grown caterpillar is green with dark head and pupates within the web.

v  Nature of damage:

Young larva initially mine into leaflets and feed on mesophyll. Later as it grow web the leaflets together and feed. Severely infested field presents a symptom as if burnt when viewed from a distance.

v  Management:

Foliar spray with acephate 1.5 g/l or chlorpyriphos 2.5 ml/l or quinalphos 2 m l/l were effective measures.

4.   Whitefly: Bemisia tabaci (Aleurodidae: Hemiptera)

v  Nature of damage: Both nymphs and adults suck sap from undersurface of leaves, excrete honeydew. Damaged leaves show uniform bronzing. For other details refer under cotton

v  Management: Foliar spray with acephate 1.5 g/l or triazophos 2 ml/l or profenophos 2 ml/l were effective measures.

EXERCISE No. 6

PESTS OF COTTON

1.   Spotted bollworms: Earias vitella & E. insulana (Noctuidae: Lepidoptera)

v  Distribution and status: Cosmopolitan. Major pest

v  Host range: Cotton, bhendi, holly hock, Hibiscus cannabinus, Abutilon indicum

v  Life history: Earias vittella has green forewigns with white streak in each of them. Earias insulana has complete green forewings Scuptured, crown shaped, deep sky blue colour eggs are deposited singly on the shoot tips, buds, flowers, fruits. Egg period is 3 days Larva is brown with dorsum showing a white median longitudinal streak; the last two thoracic segments and all the abdominal segments have two pairs of fleshy tubercles (finger shaped processes), one dorsal and the other lateral. E. vittella is without finger shaped processes. Larval period is 10-12 days. Pupation is outside the bolls in a tough, boat shaped, dirty white silken cocoon. Pupal period is 7-10 days.

v  Nature of damage:

In the beginning of the season, when the crop is a few weeks old, the small caterpillar on hatching out from the egg leads a free life for a few hours. Then it bores into top tender shoot, the portion of the shoot above the damage withers, droops and dries up. Depending upon the locality upto 50 per cent of the crop may be damaged in this manner. When the squares and bolls begin to develop, these caterpillars move from the shoots and start damaging bolls by making conspicuous holes into them. The squares and small bolls injured by the larvae drop away from the plants. The developing bolls are also damaged and some of the damaged bolls fall to the ground. The infested bolls, which are not shed, are destroyed by the larvae eating the seeds and filling them with excrement. Such affected bolls may open prematurely and badly.

2.   American bollworm/ Green bollworm: Helicoverpa armigera (Noctuidae: Lepidoptera)

v  Distribution and status: Cosmopolitan. Major pest

v  Host range: Sorghum, lablab, soybean, peas, sunflower, safflower, chillies, groundnut, tobacco, bhendi, maize, tomato.

v  Life history: Adult: Brown coloured moth with a ‘V’ shaped speck on forewing and dull black border on the hind wing. Eggs are laid on the host plants singly. The egg period is 7 days. Full grown larva is 2” long, greenish with dark brown gray lines and dark and pale bands. It shows colour variation from greenish to brown. The larval duration is 14 days. It pupates in soil for 10 days.

v  Nature of damage:

The caterpillars feed on leaves, squares, flowers and small bolls. When the

squares, flowers and bolls are attacked, they feed the internal content completely by thrusting their head inside leaving the rest of the body outside. The damaged squares and young bolls drop away from the plants. The developed bolls and open bolls are not attacked.

v  Economic threshold level: 10% of affected fruiting parts or bolls or one egg/plant or one larva/plant.

v  Management of bollworms:

A.   Monitoring: Pest monitoring through light traps, pheromone traps and in situ assessments by roving and fixed plot surveys has to be intensified at farm, village,block, regional and state levels. For bollworm, H. armigera management, an action threshold of one egg per plant or 1 larva/ plant may be adopted.

B.   Cultural practices:

1.   Grow Bt cotton viz., Bollgard I containing Cry 1 Ac protein that offers protection against American bollworm and Bollgard II containing Cry 2 Ab in addition to Cry 1 Ac which offers season long protection against Spodoptera and Helicoverpa.

2.   Grow Helicoverpa resistant varieties like L 1245, LD 135, Sujata, LK 861, Abadhita.

3.   Grow spotted bollworm resistant varieties like L 1245, JK 119-25-54, BCS 10, BCS 10-75, FBRN 2-6, HAO 66-107-1/1, Hopi, Deltapine, LH 95, UK 48G 27, Sanguineum

4.   Pre monsoon sowing during 4th week of September significantly lower the bollworm damage in rainfed areas.

5.   Synchronized sowing of cotton preferably with short duration varieties in each cotton ecosystem.

6.   Avoid continuous cropping of cotton both during winter and summer seasons in the same area as well as ratooning.

7.   Avoid monocropping. Grow less preferred crops like greengram, blackgram, soyabean, castor, sorghum etc., along with cotton as intercrop or border crop or alternate crop to reduce the pest infestation.

8.   Remove and destroy crop residues to avoid carry over of the pest to the next season, and avoid extended period of crop growth by continuous irrigation.

9.   Optimize the use of nitrogenous fertilizers which will not favour the multiplication of the pest.

10.  Judicious water management for the crop to prevent excessive vegetative growth and larval harbourage.

C.   Biological control:

1.   Application of nuclear polyhedrosis virus (NPV) at 3 x 1012 POB /ha in evening hours at 7th and 12th week after sowing.

2.   Conservation and augmentation of natural predators and parasites for effective control of the pest.

3.   Inundative release of egg parasite, Trichogramma spp., at 6.25 cc/ha at 15 days interval 3 times from 45 DAS, egg-larval parasitoid, Chelonus blackburnii and the predator Chrysoperla 1,00,000/ha at 6th, 13th and 14th week after sowing.

4.   ULV spray of NPV at 3 x 1012 POB /ha with 10% cotton seed kernel extract, 10% crude sugar, 0.1% each of Tinopal and Teepol for effective control of Helicoverpa.

D.  Chemical control :

1.   During the early stages of square formation, apply endosulfan 35 EC @ 0.2 l/ha.

2.   During bolling and maturation stage, apply any one of the following insecticides per ha; phosalone 50 EC 2.5 L quinalphos 25 EC 2.0 L, carbaryl 50 WP 2.5 kg (1000 L of spray fluid/ha)

3.   Discourage the indiscriminate use of insecticides, particularly synthetic pyrethroids.

4.   Use of proper insecticides which are comparatively safer to natural enemies such as endosulfan, phosalone, etc., at the correct dosage and alternating different groups of insecticides for each round of spray.

5.   Avoiding combination of insecticides as tank mix.

6.   Adopting proper delivery system using spraying equipments like hand compression sprayer, knapsack sprayer and mist blower to ensure proper coverage with required quantity of spray fluid and avoiding ULV applications.

7.   Proper mixing and preparation of spray fluid for each filling of spray fluid tank.

3.   Cotton pink bollworm: Pectinophora gossypiella (Gelechiidae: Lepidoptera)

v  Distribution and status: India, Pakistan, Africa, Australia, Asia. Major pest

v  Host range: Cotton, bhendi, holly hock and other malvaceous plants

v  Life history:

Larva: Varies in general color; young larva white and late instar almost black, brown or green to pale or pink with several dark and light alternating bands running the entire length. Adult: Small moth, brown or dull yellow or olive grey with dark spots on the forewing.

v  Nature of damage:

The caterpillars feed on flower buds, flowers and bore into bolls. When they bore into flower buds, they feed on developing anther and style and occasionally on ovary. When they are found in flowers, the flowers do not open and give rosette appearance. The young bolls, when attacked, are shed after a few days, but the larger bolls remain on the plant. Locules are damaged and interlocular burrowing can be noticed. Seeds are destroyed and lint gets stained. The aperture through which they make their entry into the boll is closed and it becomes difficult to differentiate between a healthy and infested boll. Due to damge ginning % of seeds and spinning quality of kapas adversely affected.

v  Management:

1.   Use pheromone trap @ 12/ha to monitor the adult moth activity.

2.   Collect and destroy the shed fruiting parts at weekly intervals.

3.   Crush the pink bollworm larvae in the rosette flowers.

4.   Spray endosulfan 2.0 L /ha in the early stages of square formation.

5.   Durign bolling and maturation stage, spray fenpropathrin 30 EC 250-340 ml or fenpropathrin 10EC 750-1000 ml or triazophos 40 EC 1.5 - 2.0 L or cypermethrin 10 EC 500-700 ml or 25 EC 180-250 ml of water/ha.

4.   Leafhopper or Jassid: Amrasca devastans (Cicadellidae: Hemiptera):

v  Distribution and status: Major pest in all cotton-growing region of India.

v  Host range: Cotton, potato, brinjal, castor, bhendi, tomato, hollyhock and sunflower.

v  Life history:

Adult green and wedge shaped, lay eggs singly within leaf veins. Incubation

period 4-11 days. Nymph light green and translucent found between the veins of leaves on the under surface. Nymphal period 7-21 days. Nymphs moult five times. Life cycle is completed in 15-46 days. Eleven generations are known to occur in a year.

v  Nature of damage:

Both nymphs and adults suck the sap from the under surface of leaves, tender leaves turn yellow, leaf margins curl downwards and reddening sets in. In the case of severe infestation leaves get a bronze or brick red colour which is typical “hopper burn”. Crop growth retarded.

v  ETL: 50 nymphs / adults per 50 leaves or yellowing and curling from the middle to upper portion of the plants in 25 % of plants in the field

v  Management

1.   Early sowing and close spacing of cotton reduces pest infestation particularly if the rainfall is heavy.

2.   Setup light trap to monitor the broods of leaf hopper and to attract and kill.

3.   Release predators viz., Chrysopa carnea.

4.   Spray monocrotophos 36 WSC @ 1000 ml/ha and NSKE 5% @ 25 kg/ha or 750 ml endosulfan 35 EC in 1000 L of water per hectare.

5.   Use resistant varieties like MCU 3, MCU 5 and MCU 9.

5.   Red cotton bug: Dysdercus cingulatus (Pyrrhocoridae: Hemiptera)

v  Distribution and status:

Uttar Pradesh, Bihar, Bombay, Andhra Pradesh and Tropical Africa, Tropical Asia, Australia, U.S.A. Central and South America and India. Regular pest at crop maturity.

v  Host Plants: Cotton, bhendi, maize, pearl millet, hollyhock, clover, sorghum and silk cotton.

v  Life history:

The adult is a red and black bug with white stripes ventrally on the abdomen. The eggs are laid in loose masses in the soil. The fecundity of the bug is 100 – 130. Egg period 4-7 days. The nymph undergoes six instars to become adult. The nymphal period lasts for 26 - 89 days. The adult bug undergoes hibernation (resting period) during winter months.

v  Nature of damage:

The damage is caused by both nymphs and adults by sucking the sap of the plant as well as that of bolls and stain the lint. They are also, therefore, termed as cotton boll stainers. The bugs are gregarious in habit. Attacked seeds loose viability. The bacterium Nematospora gossypii enters the site of injury and stains the fibre.

v  Management:

1.   Biocontrol agent Harpactor costalis is predaceous on nymph and adult. Since the pest feeds gregariously, the infested leaves or bolls can be shaken in water and drowned.

2.   Plough the field to expose the eggs.

3.   Spray fluvalinate 25 EC 200-400 ml/ha orendosulfan 35 EC 750 ml/ha.

v  Integrated pest management of cotton pests

1.   Remove cotton crop and dispose off the crop residues as soon as harvest is over.

2.   Avoid staking of stalks in the field.

3.   Avoid ratoon and double cotton crop.

4.   Adopt proper crop rotation. Use optimum irrigation and fertilizers.

5.   Synchronize the sowing time in the villages and complete the sowing within 10 to 15 days.

6.   Grow one variety throughout the village as far as possible.

7.   Avoid other malvaceous crops in the vicinity of cotton crop.

8.   Timely earthing up and other agronomic practices should be done.

9.   Hand pick and burn periodically egg masses, visible larvae, affected and shed squares, flowers and bolls and squash pink bollworm in the rosettes.

10.  Use locally fabricated light traps (modified Robinson type) with 125 Watt mercury lamps to determine the prevalence of pests and their population fluctuation.

11.  The magnitude of the activity of the moths of the cotton pink bollworm, the cutworm (Spodoptera litura) and the American bollworm can be assessed by setting up the species-specific sex pheromone trap each at the rate of 12 per ha.

12.  Apply chemical insecticides only when it is absolutely necessary and when pest population damage crosses ETL.

13.  Intercropping with pulses viz., cowpea, greengram, blackgram and soybean reduce the population of sucking pests of cotton, viz., aphid and leaf hopper. Also, the bollworm incidence is low. Besides, the highest activity of natural enemies viz., spiders and predatory lady bird beetles are significant.

 

 

EXERCISE No. 7

PESTS OF SUGARCANE

1.   Early shoot borer: Chilo infuscatellus (Crambidae: Lepidoptera)

v  Distribution and status: India, Pakistan, Indonesia, Thiawan, Philippines, Korea, Afghanistan and Burma.

v  Host range: Pearl millet, oat, barley and maize

v  Life history: Larva is dirty white with five dark violet longitudinal stripes and dark brown head. Adult is pale greyish brown moth with black dots near the costal margin of the forewings and with white hind wings.

v  Carry over: Pest hibernates as larva in stubbles.

v  Seasonal occurrence: Adasali- July to September; Preseasonal: November to December; Suru: January to March

v  Nature of damage: Dead heart in 1-3 month old crop, which can be easily pulled out, rotten portion of the straw coloured dead-heart emits an offensive odour. Larva bore number of holes at the base of the shoot just above the ground level can be seen. It is major pest in the early stage of the crop.

v  ETL: 15 % deadheart

v  Management:

1.   Apply management practice if population excess ETL of 15% dead heart.

2.   Grow resistant varieties: CO 312, CO 421, CO 661, CO 917 and CO 853.

3.   Planting in December – January escapes the incidence

4.   Intercrop with Sesbania sp.(Daincha) for reduced shoot borer incidence

5.   Trash mulching : 10 – 15 cm thickness on 3rd day after planting

6.   Earthing up – 30th day

7.   Ensure adequate moisture

8.   Remove and destroy dead hearts

9.   Apply Granulosis virus (GV) @ 1.1 x 105 granules twice on 35 and 50 DAP.

10.  Release tachinid parasitoid: Sturmiopsis inferens @ 125 gravid females.

11.  Apply carbofuran 3G @ 33 kg or fipronil 0.3 G 25.0-33.0 kg / ha in the soil before the cane setts are covered.

12.  Apply cartap hydrochloride 4G or fipronil 0.3 G at 25 kg /ha by mixing in 50 kg soil and sprinkle along the rows at 45 days after planting followed by earthing up.

13.  Spray monocrotophos 36 SL 1000 ml or endosulfan 35 EC 1000 ml or chlorpyriphos 20 EC 1000 ml or chlorantraniprole 18.5 SC 375 ml or fipronil 5 SC 1.5-2.0 L or /ha.

2.   Internode borer: Chilo sacchariphagus indicus (Crambidae: Lepidoptera)

v  Distribution and status: India, Pakistan and Sri Lanka

v  Host range: Pearl millet, rice and sorghum

v  Life history: Eggs are laid between leaf sheath and stem in clusters. Larva: White with four violet longitudinal stripes and light brown head. Pupation inside the stem in larval tunnels.Adult: Pale brown with white hind wings.

v  Carry over: Pest hibernates as larva in cane or stubbles from November to February.

v  Seasonal occurrence: May to September

v  Nature of damage: Infestation of the pest is noticed in all the stages of the crop growth. Firstly it act as as an early shoot borer causing death hearts. The activity as an internal borere starts from 3-4 months after planting and continuos till harvest. Internodes constricted and shortened, with a number of bore holes and fresh excreta in the nodal region. Affected tissues become reddened. Larva have habit to bore internodes one after the another.

v  Management:

1.   Avoid use of excessive nitrogen fertilizers.

2.   Release egg parasitoid: Trichogramma chilonis @ 2.5 ml / ha – 6 releases – 4th month onwards at 15 days intervals

3.   Release larval parasitoids: Stenobracon deesae, Apanteles flavipes,

4.   Release pupal parasitoids: Tetrastichus ayyari, Trichospilus diatraeae.

5.   Apply carbofuran 3G granules to soil @ 30/kg per hectare, if damage is severe. If the damage is acute, apply carbofuran 3 G 30 kg /ha.

3.   Top borer: Scirpophaga excerptalis (Pyralidae: Lepidoptera)

v  Distribution and status: India, Pakistan, China, Formosa, Japan, Philippines, Thailand, Bangladesh, Indonesia, Laos, Cambodia, Vietnam, Burma and Taiwan

v  Host range: Millets and other grasses

v  Life history:

Larva: Smooth, white or cream coloured with a red coloured mid-dorsal line and yellow head. Adult: White coloured moth (with a buff coloured anal tuft in the abdominal tip of female).

v  Carry over: Pest hibernates as larva in cane top throughout winter.

v  Seasonal occurrence: October or November

v  Nature of damage:

Dead heart in grown up canes, which cannot be easily pulled; dead heart

reddish brown in colour; parallel row of shot holes in the emerging leaves and red tunnels in the midribs of leaves; bunchy top appearance due to the growth of side shoots. Larva bores into the midrib of unfolded leaves and mine their way to the base.

v  Management:

1.   Grow resistant varieties: Co 724, CoJ 67, Co 1158, Co 1111

2.   Collect and destroy the egg masses.

3.   Release bio control agents like ichneumonid parasitoid:Isotima javensis@ 100 pairs/ ha (prepupal parasitoid); egg parasitoids:Telenomus beneficiens, Tetrastichus schoenobi, Trichogramma chilonis; larval parasitoids: Goniozus indicus, Chelonus sp.,; pupal parasitoid: Tetrastichus ayyari.

4.   Leaf hopper/Sugarcane pyrilla: Pyrilla perpusilla (Fulgoridae: Hemiptera)

v  Distribution and status: India, Pakistan

v  Host range: Sugarcane, wheat, barley, oats, maize, sorghum, baru, guinea grass and sudan grass.

v  Life history:

The adults lay 300 - 536 eggs in clusters on the underside of leaves. Egg

period 8-28 days. Nymphs are soft and pale brown to pale orange with two characteristic tufts of waxy secretion at the end of abdomen. Pupal period 2 – 6 months. Adult is soft, straw coloured with the head pointing forward as snout. Wings fold over the abdomen like hood; densely veined and transparent. Adult live for about 2 - 5 months. 3- 4 generations are completed in a year.

v  Nature of damage:

Nymph and adult suck the cell sap from lower surface of the leaves as a result plant losses turgidity begin to wither a gets dried up. The sucrose % of juice is adversely affected. They also excrete honey due like substances that spread on the leaves on which black fungus (Capnodium spps.) develop with affect the photosynthesis alonghwith the yield.

v  Management:

1.   Collection and distruction of egg masses.

2.   Removal of 5-6 lower most leaves helps in reduction of pyrilla population as maximum egg laying takes place on such leaves.

3.   Avoid excessive use of nitrogenous fertilizers.

4.   Set up light trap.

5.   Detrash on 150 and 210 DAP.

6.   Release 4000-5000 cocoons or 4-6 lakhs egg of Epiricania melanoleuca (Lepidopteran predator) per ha

7.   Conserve predators viz., Brumus suturalis, Chilomenes sexmaculatus and Coccinella septumpunctata.

8.   Spray endosulfan 35 EC 2 L in 1000 L water/ ha.

5.   Sugarcane woolly aphid: Ceratovacuna lanigera (Aphididae: Hemiptera)

v  Distribution and status: India. It has been posing threat as a major pest in Maharashtra since a few years and is fast spreading to new areas.

v  Host: Bamboo, Cynadon dactylon, sugarcane

v  Life history: Female reproduce parthenogenetically reproducing 15 to 35 young ones in 24 hours. The nymphal stage is 6 to 22 days. Life cycle is completed in 30 days. Adult emerge after fourth moult.

v  Nature of damage:

It is a congregation of large number of white coloured nymphs and adults on the undersurface suck the cell sap; honeydew secretion with sooty mould on upper surface of the leaves. Canes with short internodes and narrow leaves with reduced girth.

v  Management:

1.   Monitor the fields especially areas under shade where the colony establishes first.

2.   Avoid transport of sugarcane for crushing from SWA infested area.

3.   If seed material is to be moved, treat setts in malathion 0.1% solution for 15 minutes, pack in gunny bags and transport without using green or dry leaves as packing or cushion material.

4.   Practice wide-row/paired-row planting and de-trashing that allow greater aeration and light.

5.   Avoid late application of nitrogenous fertilizer and excessive irrigation.

6.   Spray infested crop with acephate 75 SP 2.0 kg or monocrotophos 36 WSC 2.0L or dimethoate 30EC 2.0 L in 1000 L of water directing the spray fluid towards the under surface of leaves. Un-infested clumps in about 3 metre radius of the infested clumps may also be similarly treated with the insecticide.

7.   Collect leaves bearing predators from other parts of the field and release.

8.   Mass produce predators viz.,Dipha aphidivora , Micromus igorotus and Eupeode confrater in shade-net houses and release them in infested fields.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

EXERCISE No. 8

NON INSECT PESTS OF FIELD CROPS

There are different kinds of insect causing damage to variety of crops, animals and directly affecting mans interest known as non- insect pests. Few of the most

important non- insect pests on crops are as follows,

1.   Mites: Mites also known as Acarina belong to phylum Arachnida, to which spiders also belong. These are minute organisms that can rarely be seen with naked eyes. Mites cause heavy damage in crops especially in vegetables and ornamentals. Mites constitute a large group with its members inhabiting a variety of habitats like soil, water, plants, animals, processed food and animal waste. Both nymphs and adults suck sap from plant parts like leaves, terminal or axillary shoots, fruits etc with their needle like chelicerae and cause symptoms like;

1.   Formation of white blotches on leaves in vegetables.

2.   Characteristic red spots that enlarge and coalese making whole leaf reddish.

3.   Drying of leaves and stems in sugarcane.

4.   Formation of crowded buds, crumpled shoots in mango.

5.   Formation of pinkish blotches on fruits of citrus.

6.   Curling of leaves upwards in chillies.

7.   Formation of warts and longitudinal tissues on nuts of coconut.

8.   Act as vectors by transmitting viral diseases. e.g., Tetranychus neocaledonicue, Acerie cajani.

v  Management:

1.   Removal of alternate hosts in the field.

2.   Spraying of sulphur @ 3 gm/ Dimethoate 30 EC @ 2 ml/lt/ Methyldemeton 25 EC @ 2 ml /lt / kelthane (Dicofol) 5 ml /lit / Ethion @ 1 ml/lit.

3.   Fungal pathogen, Hirsutella thompsoni reported to be effective against coconut eriophid mite.

4.   Predaceous insects on mites e.g., Scolothrips indicus, Scymnus gracilis.

2.   Rats and mice (Rodents):

v  Family: Muridae; Order: Rodentia; Class: Mammalia

Rodents are of two type namely Commensel rodents and Field rodents

1.   Commensel rodents:

ü  House mouse - Mus musculus

ü  House rat or black rat – Rattus rattus

ü  Common Indian field mouse - Mus musculus booduga

ü  Brown rat - Rattus norvegicus

2.   Field rodents:

ü  Soft furred field rat or grass rat (Millardia meltada)

ü  Indian Mole Rat or Lesser Bandicoot Rat (Bandicota bengalensis)

They cause severe damage to crops and domestic commodities, thereby requiring to be controlled effectively. Several types of diseases are known to be transmitted by rats. Besides consuming considerable quantity of food, they contaminate much more by urine, faeces, and hairs and sebaceous secretions.

v  Management of rodents:

1.   Killing rats by sticks.

2.   Trapping the rats using traps.

3.   Snap neck trap kills the rat instantly.

4.   Live catch traps trap the rats alive Eg. Single rat trap, wonder trap.

5.   Burrows in the fields can be flooded with water, which kill the rats.

6.   Chemicals used for controlling rodents can be classified into two types;

A.   Acute poison: That are used in single dose

Zinc phosphide: To be used only in fields not in houses with a recommendation at 2.5% technical grade in pre-baiting is compulsory for effective results i.e., 95% flour + 1 to 2% Zinc phosphide + 2% groundnut oil + 1% sugar

B.   Anticoagulants: e.g.,Warfarin, Fumarin, Toumarin, Recumin

These poisons are lethal when consumed for several days. They prevent blood clotting and break cell wall of blood capillaries leading to haemorrhage. Rats normally die in aerated areas. House rat and house mouse die after 2-5 days of continuous feeding.

F Bromadiolone is only registered and recommended @ 0.005% ai in cereal baits to be used in pulsed baiting technique

F Fumigants: e.g., Aluminium phosphide (CP) solid/ Ethelen dibromide (EDB) /Ethelene dichloride carbontetrachloride (EDCT)

v  Natural enemies

Cats, dogs, owl, hawks and snakes. Also Salmonella sp. of virus can be used for rodent control but not recommended due to health threat to non target species.

3.   Hare and rabbit:

Hares and rabbits are one of the best known wild mammals and of considerable economic importance. They are nocturnal and graze mainly on grass, herbs, scrubs, bulbs, roots, bark etc. Instances of their becoming pests on agricultural crops are widely known throughout the country. They do considerable damage to crops like wheat, barleygram, maize, jowar, bajra, pea, mustard, bean, cabbage and others. They are browse on young fruit trees and forest plants.

4.   Birds: Many birds such as;

F Pigeons and seagulls eat human food and carry disease.

F Woodpeckers peck at rooftops and also nest in them. They cause structural damage to houses.

F Parrot: (Psittacula spp.): About eight species of parrots have been recorded in India. Out of these species, Large Indian parakeet (P. eupatria) is very common in Maharashtra. This species causes heavy damage to all sorts of near-ripe fruits such as guava, ber, mango, plums, peaches by eating fruits and also spoiling the fruits by cutting it with beak.

F Common myna was declared by IUCN Species Survival Commission as one of the world's most invasive species and one of only three birds in the top 100 species that pose an impact to biodiversity, agriculture and human interests.

F Cowbirds are brood parasites, which cause declines in local songbird populations.

F Crow Corvus spp. Damage wheat, cobs of maize, ripe fruits of fig, mulberry.

F House sparrow Passer domesticus damages the earheads of jowar, maize, bajra and soft and fleshy fruits such as mulberry and fig.

F Yellow throated sparrow causes havey damage to wheat and barley.

v  Management of Birds:

1.   Trapping the birds in nets or catching them with the help of sticky substance ‘Lassa’.

2.   A piece of Chapatti dipped in 0.04% parathion and placed on the top of roof is a good bait for crows.

3.   Parrots and sparrows are repelled by spraying 0.6% thiurun’ on wheat crops at milk stage.

4.   Scaring devices using mechanical, acoustic and visual means are normally employed, i.e,. beating of drums to produce sounds is still in vogue in many parts of the country particularly during harvesting.

5.   Fire crackers placed at regular intervals along a cotton rope. The rope burns from one end and ignites the crackers at regular interval which produce sounds and scare away the birds.

6.   Loud sounds due to the burning of acetylene gas produced at intervals are utilized to scare away birds and small animals.

7.   Birds may be scared by display of scare crows, dead birds and visually attractive flags etc.

 

 

 

 

 

 

 

 

 

 

 

EXERCISE No. 9

STORE GRAIN PESTS

In India, post-harvest losses caused by unscientific storage, insects, rodents, microorganisms etc., account for about 10 per cent of total food grains. The major economic loss caused by grain infesting insects is not always the actual material they consume, but also the amount contaminated by them and their excreta which make food unfit for human consumption. About 500 species of insects have been associated with stored grain products. Nearly 100 species of insect pests of stored products cause economic losses

v  Storage insect pests are categorized into two types viz.

F Primary storage pests: Insects that damages sound grains are primary storage pests i.e., Internal and External feeders

F Secondary storage pests: Insects that damage broken or already damaged grains secondary storage pests.

A.   Primary storage pests:-

1.   Rice weevil: Sitophilus oryzae (Curculionidae: Coleoptera)

v  Distribution and status:

World-wide and is found practically throughout India. It is the most

destructive pest of stored grain. The rice weevil may be found in the paddy fields as well.

v  Host range: Rice, sorghum, wheat, barley, maize

v  Life history: Full grown larva is 5 mm in length and plumpy, fleshy, legless creature. Reddish brown beetle adult is 3 mm in length, with a cylindrical body and a long, slender, curved rostrum. Its elytra bear four light reddish or yellowish spots. The rice weevil breeds from April to October and hibernates in winter as an adult inside cracks and crevices or under wheat bags in the godowns. During the active season, females lay about 400 eggs on the grain by making a depression and the hole is sealed with a gelatinous secretion. Eggs hatch in 6-7 days and the young larvae bore directly into grain, where they feed and grow to maturity. Then, they pupate inside the grain. The pupal stage lasts 6-14 days. On emergence, adult weevil cuts its way out of the grain and lives for about 4-5 months. At least generations are completed in a year.

v  Nature of damage: Both the adults and the grubs cause damage. The developing larva lives and feeds inside the grain causing irregular holes of 1.5 mm diameter on grains of rice, sorghum, wheat, barley, maize before harvest and in storage. The weevils destroy more than what they eat.

2.   Lesser grain borer: Rhyzopertha dominica (Bostrychidae: Coleoptera)

v  Distribution and status: India, Algeria, Greece, United States, New South Wales (Australia), Japan China.

v  Host range: Wheat, rice, maize, sorghum, barley, lentils, army biscuits, ship biscuits, stored, dried potatoes, corn flour, beans, pumpkin seeds, tamarind seeds and millets.

v  Life history: The larva is about 3mm long, dirty white, with light-brown head and a constricted elongated body. The adult is a small cylindrical beetle measuring about 3 mm in length and less than 1 mm in width. It is shining dark brown with a deflexed head, covered by a crenulated hood-shaped pronotum. No morphological difference separates the two sexes. The pest breeds from March to November and in December, it enters hibernation as an adult or as a larva. A single female can lay 300-400 eggs in 23-60 days at the rate of 4-23 eggs per day. The eggs are laid singly among the frass or are glued to the grain in batches. When freshly laid, the eggs are glistening white, but later on a pink opaque line appears on them. The incubation period is about 5-9 days. Larva cuts a circular hole in the pedicel end of the eggs and comes out of it. Larval period 23 - 50 days, pupal period 4 - 6 days and adult live for about 40 – 80 days. There are 5 -6 generations in a year.

v  Nature of damage:

Both the adults and the grubs cause damage in warm climate. The adults bore into the grains and completely hallow out the grain kernals and only barn coat is left. The adults are powerful fliers and migrate from one godown to another, causing fresh infestation. Adults produce a considerable amount of frass, spoiling more than what they eat. The grubs stage can feed inside the grain or on flour or on grain destroyed by adults.

3.   Angoumois grain moth: Sitotroga cerealella (Gelechiidae: Lepidoptera)

v  Distribution and status:

Worldwide in the Indian sub-continent, the pest is more abundant in the

mountainous areas or where the climate is rather mild.

v  Host range: Paddy, wheat, maize, sorghum, barley, oats etc.

v  Life history: A full grown larva is about 5 mm long, with a white body and yellow brown head. The adult is a buff, grey yellow, brown or straw coloured moth, measuring about 10-12 mm in wing expanse. The characteristic feature is the presence of the narrow-pointed wings fringed with long hair. Breeding takes place from April to October. The insect overwinters as a hibernating larva and as the season warms up, it pupates in early spring. Females start laying eggs singly or in batches on or near the grain. The eggs are small and white, when freshly laid, turning reddish later on. A single female lays, on an average, 150 eggs, usually within a week after mating. Egg period is 4-8 days. The larval stage may last about 3 weeks. Before pupation, the larva constructs a silken cocoon in a cavity. Pupal period is 9 -12 days and the adult live for about 4 - 10 days. During the active season, the life-cycle is completed in about 50 days. Several generations completed in a year.

v  Nature of damage: The damage is at its maximum during the monsoon. Only the larvae cause damage by feeding on the grain kernels before harvest and also in store. The larva bores into grain and feeds on its contents. Exit holes of 1 mm diameter with or without a trap door, are seen on the affected cereal grains. As it grows, it extends the hole which partly gets filled with pellets of excreta. It imparts unhealthy appearance and smell. In a heap of grain, the upper layers are most severely affected.

4.   Pulse beetle: Callosobruchus maculatus (chinensis) (Bruchidae: Coleoptera)

v  Distribution and status: USA, Mauritius, Formosa, Africa, China, the Philippines, Japan, Indonesia, Sri Lanka, Myanmar and India.

v  Host range: Gram, mung (Phaseolus aureus), moth (Phaseolus aconitifolius), peas, cow peas, lentil and arhar (Cajanus cajan), cotton seed, sorghum and maize.

v  Life history: Larva is whitish with a light-brown head. The mature larva is 6-7 mm long. The adult beetle measuring 3-4 mm in length, is oval, chocolate or reddish brown and has long serrated antennae, truncate elytra, not covering the pygidium. The pest breeds actively from March to the end of November. It hibernates in winter in the larval stage. A single female lays small, oval, scale like 34-113 eggs at the rate of 1- 37 per day. Egg period is 6 -16 days, larval period 10 -38 days. The hibernating larvae take 117- 168 days to complete their development. The pupal stage lasts 4-28 days. The adult escapes by cutting a circular hole in the seed coat and such grains can be spotted easily. The average life-span of an adult is 5-20 days. The insect passes through 7-8 overlapping generations in a year.

v  Nature of damage:

The adult and grub feed on the grain by making a small hole during monsoon season. Infested stored seed can be recognized by the white eggs on the seed surface and the round exit holes with the 'flap' of seed coat. Kabuli types are particularly susceptible. Though attack been seen in storage sometimes may be carried from the field where the eggs are been laid on the green pods.

5.   Khapra beetle: Trogoderma granarium (Dermestidae: Coleoptera)

v  Distribution and status: Worldwide

v  Host range: The Khapra beetle will attack any dried plant or animal matter. It prefers grain and cereal products, mainly wheat, barley, oats, rye, maize, rice, flour, malt, and noodles. It can also feed on animal products such as dead mice, dried blood, and dried insects.

v  Life history:

The insect breeds from April to October and hibernates in the larval stage

from November to March in cracks and crevices. Female begins to lay white

translucent eggs on the grains, singly or sometimes in clusters of 2 -5. The eggs are rather cylindrical, rounded at one end and narrow at the other. A female may lay 13 - 35 eggs in 1 - 7 days at the rate of 1 - 26 eggs per day. The egg period varies from 3 -10 days. Larval period is 20 - 40 days and pupal period is 4 - 6 days. Pupation takes place in the last larval skin among the grains. The adults are incapable of flying. There are 4-5 generations in a year. Fresh yellowish-white larva grows 4mm long and

turns brown. The adult is a small dark-brown beetle, 2-3 mm long, with a retractile head and clubbed antennae. The entire body is clothed in fine hairs.

v  Nature of damage:

The greatest damage is done in summer from July to October. The grubs eat the grain near the embryo or at any other weak point and from there proceed inwards. They usually confine themselves to the upper 50 cm layer of grains in a heap or to the periphery in a sack of grains. They can reduce the grain to a mere frass. Since the larvae are positively thigmotactic, they can be collected by merely placing gunny bags on a heap of grain.

B.   Secondary storage pest: -

1.   Saw toothed grain beetle: Oryzaephilus surinamensis (Cucujidae: Coleoptera)

v  Life history:

It is slender, dark, narrow, flattened beetle having a row of saw like sharp

teeth on each side of the prothorax. The antenna is clubbed and elytra cover abdomen completely. It lays 300 whitish eggs loosely in cracks of storage receptacles of godown. The eggs period is 3 -17 days. The larva is slender, pale cream in colour with to slightly darken patches on each segment. The larval period is 14- 20 days. It pupates in a protective cocoon like covering with sticky secretion. The pupal period is 7-21 days.

v  Nature of damage:

It feed on grains, dried fruits etc by scarving of grain surface or burrowing holes in them. It attacks rice, wheat, maize, cereal products, oil seeds and dry fruits.

2.   Long headed flour beetle: Latheticus oryzae (Tenebrionidae: Coloeptera)

v  Life history:

The beetle is light brown in colour with longated body, measuring 2 -3 mm in length and resembles Tribolium castaneum. It lays 400 white eggs singly on grain and seams of the bags. The incubation period is 7 – 12 days. The grub is small, white active which feeds voraciously. The larval period is 15-80 days. It pupates for 5-10 days. Life cycle is completed in 25 days at 35 0 and 70% relative humidity. Resembles Tribolium. Head is longer in proportion to the body than that of Tribolium, paler and brighter than Tribolium.

v  Nature of damage:

Both grubs and adult beetles feed on the milled products. It occurs as secondary infestation in stored grain. It attacks cereal flour, packaged food, rice and rice products. Occurs as secondary infestation in stored sorghum, wheat, etc.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

EXERCISE No. 10

STORAGE STRUCTURE AND METHODS OF GRAIN STORAGE

v  STORAGE STRUCTURE AND METHODS OF GRAIN STORAGE

The most common food ofIndian people is wheat and rice which are stored in different ways. The farmer retains a little part oftheir production for selling it at better prices, for home consumption, seeds and other purposes. Similarly, Food Corporation of India stores wheat for distributing it to defence and also to State Government at cheaper rate. It also checks higher prices in the market. Therefore, storage ofwheat and rice is important for our country. This chapter deals with the method ofstorage in practice at various levels viz. Govemment/Semi Government and at fanner level. It is thus classified in two categories

A.   Scientific Storage Method

B.   Traditional Storage Method

A.   Scientific Storage Method:

Holding and preservation ofstocks stored to maintain the quality synchronous to time lag and to keep it at a particular level during various operation such as loading/unloading ofstock and unkeep the stocks stored hygienically sound for a length of time till its liquidation is known as scientific method of storage which may either be in bags or in bulk. This method ofstorage is generally practised by Govemment/Semi- Govemment, warehouses, which have enough infrastructural facility available and various coordinating factors viz. trained personnels and adequate scientific know-hand, regular input availability and a network of godowns. This method ofstorage can either be in bags or in bulk.

1.   Bag Method:- In this method ofstorage, wheat is filled injute bags keeping in view the fact that wheat is a living organism requiring respiration which is not possible in polythene bags. After filling wheat in bags the mouth ofbag is stitched and stencilled to mark the marketing year. Then bags are stored in godowns in a block pitched to a scientific height so that easy counting of bags could be possible. These godowns are built on a raised plateform of 3 to 4’ in height to ensure non-proliferation of rodents and adequate length and width to economise cost with the bags stored to a certain height provide it with a kind ofroofing and ventilators so as to ensure it free from moisture, insects and adequate aeration. Moreover, the block formation is typical and of a certain prescription in which the bags are pitched from block to block to make a stake which has a certain number of bags again and is uniform in nature. The stacks are fonned in such a manner as to keep specifically ways to the entire length of a particular unit and galleries before doors for easy preservation and other related operations. These galleries also help in periodic inspection/treatment of stocks stored in godown.

2.   Bulk Method:- This is one ofthe fonn ofstoring surplus grain in an improved structures of storage designed with latest technological know-how by using steel reinforced concrete of different size. The bins traditionally used are built and reformed in certain capacity in different shape and size and also fitted with mechanized grain lifting devices which fonn the elevator silos. There are three types of improved bulk storage methods in use:

A.   Hexagonal Bins: In the recent years standard famous concrete hexagonal bins with main hole at top and spout at the bottom are constructed in different sizes.

B.   Circular Bins: Using the same material and principle used in hexagonal bins, the circular over ground bins are built which can be put in pair and row with grain discharged from opposite side.

C.   Elevator Silos: On the bais of shape and principle used in bins the big structure of circular square, hexagonal, opatagonal, flopper bottom, flat bottom, deep and shallow ‘BUNJURE’ are constructed ofvarious capacities provided with mechanical grain filling, storing devices. This has revolutionized the system of scientific storage throughout the world to keep the grain hygienically safe for a period of time with proven immunity from various loss causing agents.

The advance form of bulk storage in silos keep the grain free from insect, moisture even caused by atmospheric humidity during monsoon period, rodent damages, low-cost treatment if deterioration from any particular loss is perceptible and do economise in cost of gunny bags due to reuse of gunny bags dunnage material. The biggest loss causing agent in this form of storage is moisture penetrated in the structure either due to cracks. From the walls of the structures or grain stored at the time of filling beyond tolerance limit may cause serious damage to store grain. Therefore, if a qualitative safe guard can be observed in construction of silos and permissible limit of grain filling up to a particular level of moisture can be ensured, this can prove best scientific method with all advantageous effect of a proven technology.

B.   Traditional Storage Method: Since time of the yore man has invented methods to save grain from deteriorating factors which are called Traditional Method of Storage. There are different types of traditional method of storage such as cellars, granaries, bukhari, Kuthila, open under roof, theka, adda, under straw heap etc. which had been practiced in the past and some of them continue to be practised even now. These methods were advantageous to fanners of different ages due to lack of resources which involved lesser per quintal investment and easy accessibility of the farmers. These methods were most susceptible to loss which was caused by moisture because of scant and muddy structure which were little resistant to rain and also weather humidity resulted in infestation or got infected due to growth or micro-organisms. With the growth of agrarian communities, the improved fonn of structure came into existence such as jute bags, steel bins etc. which proved to be more effective in controlling damages in all aspect and was favorable over the traditional methods. The most common methods used by the farmers to store wheat in India is as follow:

1.   Bulk Method: In this method ofstorage, a convenient room of the house is selected for storing wheat (or any other grain). Loose wheat is stored in that room. This method is mostly used by the large fanners who expect to have quantity of wheat and cannot buy gunny bags or other kind of costly structures.

v  Merits: This method has following merits:

1.   Wheat can be stored in huge quantity.

2.   A convenient room can be selected easily with easy efforts.

3.   It can be easily constructed and can have multipurpose advantages. It can be utilised easily as living room after liquidation of stored grain.

4.   Storing of grain as well as liquidation is easy involving low cost.

v  Demerits: This method has following demerits:

1.   In this method, the losses are more as compared to other methods of storage.

2.   This method is not a modem method of store and is very much susceptible to humidity.

2.   Bag Method: Most of the fanners retain their commodities in bags and mostly this type of method is used for storing wheat. After filling the grains in gunny bags, it is packed by proper stitching and they are kept either in room or in a verandah where a thin layer of straw is spread to prevent it from damp. Later the bags are stacked one upon other so that they occupy less space.

v  Merits: This method has following merits:

1.   The grain can be stored safely for a longer period of time.

2.   It is easy to handle and direct loading is also possible. It is more convenient method of storage as the bags can be carried from one place to another place. It provides perfect mobility.

3.   The inspection of stocks is frequently possible and curative treatment can also be taken easily.

4.   Losses are less as compared to other methods.

v  Demerits: This method has following demerits

1.   The gunny bags being a costly input with a short life span proved expensive on cost factor.

2.   The structure employed in this method is neither moisture proof or insect proof nor rodent protected as such frequent inspection and treatment is required which is a costly affair.

3.   Kuthila Method: Kuthila are sort of homemade silos and are made up of mud, chaff and animal dung. They are constructed in parts and their construction process is rather slow. After one part is constructed and dried the other part is superimposed upon it. The silo is conical in shape with the base about a meter in diameter and about one and half meter in height. Its capacity is about one and half tonnes of grain. This method is mostly used by the small fanners. This method is very much susceptible to moisture.

v  Merits: This method has following merits;

1.   It is relatively less expensive and can be constructed by family members in leisure time.

2.   It covers very little space.

3.   Small sized Kuthila can be moved freely from one place to another at farmers own convenience.

v  Demerits: This method has following demerits;

1.   Heavy losses occur due to moisture in this method.

2.   This method is not suitable for storing huge quantities ofgrain for longer period.

3.   Quality of commodity deteriorates gradually.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

EXERCISE No. 11

PREVENTIVE AND CURATIVE METHODS OF STORED GRAIN

PESTS

v  Integrated Management Of Stored Produce Pests

The control methods of stored produce pests can be categorized into preventive and curative measures.

A.   Preventive measures

1.   Sun Drying: of grains to reduce the moisture content of grain below 8% will reduce the multiplication of pests, which can be done by spreading thin layer of grain in sun. Dryers can also be used.

2.   Mixing of inert dust: such as clay, ash etc cause injuries and laceration on cuticle resulting dessication and death of insect.

3.   Bagging: is done after proper drying and stored in new gunny bags or free from pest infestation to insect. Old gunny bags should be fumigated by 0.1% malathion or DDVP to avoid cross infestation.

4.   Godown hygine: Seal all the godown cracks and crevices with cement. All rat burrows sealed with cement. Before storing grains, godown infested by sparying malathion 01.%.

5.   Care while storing: Proper dunnage to protect grains from moisture. Wooden crate dunnage with layer of malting is necessary helping to circulate the air and prevent losses due to moisture accumulation.

6.   Proper stocking of bags to facilitate the inspection and treatment of grains.

B.   Curative measures:

1.   Ecological methods:

ü  Manipulate the ecological factors like temperature, moisture content and oxygen through design and construction of storage structures/ godown and storage to create ecological conditions unfavourable for attack by insects.

ü  Temperature above 420 C and below 150 C retards reproduction and development of insect while prolonged temperature above 450 C and below 100C may kill the insects.

ü  Dry the produce to have moisture content below 10% to prevent the buildup of pests.

ü  Kill the pests bio stages harbored in the storage bags, bins etc., by drying in the sun light.

ü  Store the grains at around 10 % moisture content to escape from the insect’s attack.

ü  Manipulate and reduce oxygen level by 1% to increase the CO2 level automatically, which will be lethal to all the stages of insects.

2.   Physical methods:

ü  Provide a super heating system by infrared heaters in the floor mills and food processing plants to obtain effective control of pests since mostly the stored produce insects die at 55 –600C in 10 – 20 minutes.

ü  Modify the storage atmosphere to generate low oxygen (2.4% and to develop high carbon di oxide (9.0 – 9.5) by adding CO2 to control the insects.

ü  Seed purpose: Mix 1 kg of activated kaolin (or) lindane 1.3 D (or) malathion 5 D for every 100 kg of seed and store/pack in gunny or polythene lined bags.

ü  Grain purpose: Mix 1 kg activated kaolin for every 100 kg of grain and store. To protect the pulse grains, mix activated kaolin at the above dosage or any one of the edible oils at 1 kg for every 100 kg of grain or mix 1 kg of neem seed kernel for every 100 kg of cereal / pulse and store.

ü  Do not mix synthetic insecticides with grains meant for consumption.

3.   Cultural methods

ü  Split and store pulses to escape from the attack by pulse beetle since it prefers to attack whole pulses and not split ones.

ü  Store the food grains in air tight sealed structures to prevent the infestation by insects.

4.   Mechanical methods

ü  Sieve and remove all broken grains to eliminate the condition which favour storage pests.

ü  Stitch all torn out bags before filling the grains.

5.   Chemical methods

ü  Treat the walls, dunnage materials and ceilings of empty godown with malathion 50 EC 10 ml/L (or) DDVP 76 WSC 7 ml/L spray solution/10 sq.m.

ü  Treat the alleyways and gangways with malathion 50 EC 10 ml/L or DDVP 76 WSC 7 ml/ L (1 L of spray fluid/270 m3).

ü  Spray malathion 50 EC 10 ml/ L with @ 3 L of spray fluid / 100 m2 over the bags.

ü  Do not spray the insecticides directly on food grains.

ü  Use knock down chemicals like lindane smoke generator or fumigant strips pyrethrum spray to kill the flying insects and insects on surfaces, cracks and crevices.

ü  Use seed protectants like pyrethrum dust, carbaryl dust to mix with grains meant for seed purposes only.

ü  Decide the need for shed fumigation based on the intensity of infestation.

ü  Check the black polythene sheets or rubberized aluminium covers for holes and get them ready for fumigation.

ü  Use EDB ampoules (available in different sizes 3 ml, 6 ml, 10 ml, 15 ml and 30 ml) at 3 ml/quintal for wheat and pulses and 5 ml/ quintal for rice and paddy (Do not recommend EDB for fumigation of flour oil seeds and moist grains)

ü  Use EDCT (available in tin containers of 500 ml, 1 liter and 5 litres) at 30– 40 litres/ 100 cubic meter in large scale storage and 55 ml/quintal in small scale storage.

v  FUMIGATION

Use fumigants like ethylene dibromide (EDB), ethylene dichloride carbon tetra chloride (EDCT), aluminium phosphide (ALP) to control stored produce pests effectively. Apply aluminum phosphide (available in 0.6 g and 3 gram tablets) @ 3 tablets (3 gram each) per tonne of food grains lot with help of an applicator. Choose the fumigant and work out the requirement based on the following guidelines.

F 3 tablets of aluminum phosphide 3 g each per tonne of grain.

F 21 tablets of aluminium phosphide 3 g each for 28 cubic meters

F Period of fumigation is 5 days

Mix clay or red earth with water and make it into a paste form and keep it

ready for plastering all-round the fumigation cover or keep ready sand snakes. Place the required number of aluminium phosphide tablets in between the bags in different layer. Cover the bags immediately with fumigation cover. Plaster the edges of cover all round with wet red earth or clay plaster or weigh down with sand snakes to make leaf proof. Keep the bags for a period of 5-7 days under fumigation based on fumigant chosen. Remove the mud plaster after specified fumigation periods and lift cover in the corner to allow the residual gas to escape. Lift the cover after few hours to allow aeration.