Pests of Cruciferous Crops, their Damage Symptoms and Management Practices.pptx

Pests of Horticultural Crops
Pests of Cruciferous Crops like Diamond back moth, Aphids, Painted bug, Cabbage butterfly, Leaf eating caterpillar, Flea beetle, Head borer, Mustard saw fly

1. Pests of Cruciferous Crops Presented By Prof. Shid D. C.

2. 1. Diamond back moth S.N. - Plutella xylostella Family - Plutellidae Order - Lepidoptera Marks of identification - Adults : Moth small, brownish grey in color having three pale whitish triangular spots on their hind margins of forewings which forms a diamond pattern when the insect is at rest with wings folded along the body so that called as diamond back moth. Caterpillar: Small, greenish smooth tapering at both ends. Host plants: Serious past of Cabbage and cauliflower, but also feeds on other crucifers and solanaceous plants.

3. Life history: Eggs : On the underside of leaves Pupa : Pupation on the leaves in silken cocoons No. of generations: 5-7/year Nature of damage – Young larva feed on epidermis of leaves while full grown larva bore inside the head. Round transparent patches appear on leaves due to feeding. In case of severe infestation the plants may be completely skelotonized.

4. Management practices – Grow mustard as trap crop Remove and destroy all debris and stubbles after harvest of crop Install pheromone trap to monitor DBM adults @ 5 /ha and 25/ha for mass trapping Apply Bacillus thuringiensis formulation @1 g/L or NSKE 4% spray Conserve larval parasitoids viz., Cotesia plutellae Bt@ 1kg/ha Depending upon the pest intensity, spray any of the following insecticide with 500 -1000 L water/ha- Chlorantraniprole 18.5 SC 50 ml, Fipronil 5 SC 800-1000 ml, Quinalphos 25 EC 1000 ml, Novaluron 10 EC 750 ml

5. 2 . Aphids S.N. - Brevicoryne brassicae Family - Aphididae Order - Hemiptera Host plants : Cruciferous crops, brinjal , potato, tomato sweet potato etc. Life history : They reproduce parthenogenetically .

6. Nature of damage - They are found in large number on undersurface of leaves and on tender shoots. The nymphs and adults suck the cell sap as a result affected leaves turn yellow and subsequently dries. The aphids also excrete honeydew on which a fungus develops and rapidly covers the plant with sooty mould that interferes with photosynthetic activities of plants. The growth of the plant is stunted and yield is adversely affected.

7. Management practices – Set up yellow sticky trap @ 10 / ha. Spray any one of the following: Dimethoate 30 EC 1000 ml/ha Methyl demeton 25 EC 1000 ml/ha Neem oil 2.0 L/ha Azadirachtin 0.03% 2.5-5.0 L/ha Dimethoate 30EC 6.0 ml/10 lit.

8. 3 . Cabbage butterfly S.N. - Pieris brassicae Family - Pieridae Order – Lepidoptera Host plants : cabbage, cauliflower, knol-khol and it may also attack turnip, radish, sarson , toria ( Brassica campestris ) and other cruciferous plants Marks of identification: Adult: White butterfly Larva: Velvetty bluish green in colour with black dots, Yellow dorsal and lateral stripes covered with white hairs.

9. Life history : Eggs - On the upper or the lower side of leaf Pupa - Pupate at some distance from the food plants, often in barns or on trees . Nature of damage – The caterpillars alone feed on leaves, young shoots. When young, they feed gregariously but the grown-up caterpillars migrate from one field to another. The first instar caterpillars just scrape the leaf surface , whereas the subsequent instars eat up leaves from the margins inwards, leaving intact the main veins. Often, entire plants are eaten up.

10. Management practices When in the gregarious stage, the caterpillars can be easily controlled by picking and destroying the infested leaves. The grown-up caterpillars should be controlled with 500 ml of dichlorvos 76 SC in 600-900 L, quinalphos 25 EC @1000 ml of water per ha. Conserve larval parasitoid Apanteles glomeratus (Braconidae) in the natural populations.

11. 4 . Painted bug S.N. - Bagrada hilaris Family - Pentatomidae Order - Hemiptera Marks of identification: Nymphs: Reddish in colour . Adult: Bug is black in colour with red and yellow lines Life history : Eggs - On the undersides of cotyledons, leaves, stems, and in the soil near the base of plants

12. Nature of damage - Both nymphs and adults suck the cell sap from the leaves. Infested plants finally dry up.

13. Management practices – Deep ploughing so that the eggs of painted bugs are destroyed Early sowing is needed to avoid pest attack Irrigate the crop during four week after sowing to reduce pest attack Quick threshing of the harvested crop should be done The bugs usually congregate on the leaves and stem, which can be jerked to dislodge them and killed in kerosinised water Spray the crop with dimethoate 30 EC 2 ml/lit. of water.

14. 5 . Flea beetle S.N. - Phyllotreta cruciferae Family - Chrysomelidae Order - Coleoptera Host plants- Mustard, radish, turnip, cabbage, cauliflower, knoll- khol , sweet peas etc. Life history : Eggs: In the soil around the host plants. Pupa : Pupation in soil 7-8 generations in a year.

15. Nature of damage : Adult beetle feeds on the leaves by making round holes giving shot whole appearance. The stem, flower and even pods may also be attacked. Decaying odour is emitted by the cabbage plants. Management practices – Collect and destroy the damaged plants. Spray 2.5 kg of carbaryl 50 WP in 750 litres of water per ha.

16. 6 . Leaf eating caterpillar S.N. - Spodoptera litura Family - Noctuidae Order - Lepidoptera Host plants- Polyphagous Marks of identification - Larva- Young caterpillars are light green with black head or black spots. Well grown caterpillars are grey or dark brown Adult- Adult moths are brownish colour . Forewings are brown colour with wavy white marking, Hindwings are white colour with brown patchs along the margin

17. Life history : Eggs - On leaves Pupa - In soil Nature of damage - After hatching from the eggs caterpillar feed voraciously on leaves. In case of severe infestation complete defoliation is noticed.

18. Management practices Plough the soil to expose and kill the pupae Grow castor along border and irrigation channel as trap crop Flood the field to drive out the hibernating larvae Set up light trap @1/ha Pheromone traps (Spodolure) @ 15/ha to attract male moths Hand pick grown up larvae and kill them Spray SlNPV @ 250 LE/ha Spray chlorpyriphos 20 EC 2lit/ha or dichlorovos 76 WSC 1 lit/ha

19. 7 . Head borer S.N. - Hellula undalis Family - Crambidae Order – Lepidoptera Marks of identification - Larva- Full grown larva are greyish-yellow with seven purplish brown longitudinal stripes. Adult- Pale greyish brown moth with wavy grey markings.

20. Life history : Site of oviposition : On leaves Site of pupation : In the larval burrow itself or in the soil. Nature of damage : Caterpillars web the leaves and bore into stem, stalk or leaf veins. They bore into the cabbage head also making it unfit for consumption. The damage results in Webbed leaves. Holes in cabbage head with fecal matter. Management practices - Collection and careful destruction of the larvae at gregarious stage with leaves twice a week. For control of grown up larvae apply carbaryl 50 WP@ 375 g in 150 litre of water/ha

21. 8 . Mustard saw fly S.N. - Athalia lugens Family - Tenthredinidae Order – Hymenoptera Marks of identification - Larva- Dark green or Greenish black larvae have 8 pairs of abdominal prolegs . There are five black stripes on the back, and the body has a wrinkled appearance Adult- Small orange yellow insects with black markings on the body and have smoky wings with black veins

22. Life history : Site of oviposition : Along the underside of the leaf margins Site of pupation : In the soil. 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.

23. Management practices - Summer ploughing to destroy the pupa. Early sowing should be done. Maintain clean cultivation. Apply irrigation in seedling stage is very crucial for sawfly management because most of the larvae die due to drowning effect. Severe cold reduces pest load. Collection and destruction of grubs of saw fly in morning and evening Conserve Perilissus cingulator (parasitoids of the grubs), and the bacterium Serratia marcescens which infect the larvae of sawfly. Spray the crop with quinolphos 25 EC @ 625ml/ha in 600 to 700 litres of water per ha.

24. THANK YOU