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KERALA AGRICULTURAL UNIVERSITY
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Table 13. Common natural enemies of insect pests found in rice ecosystem
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Description of biocontrol agents |
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| Name | Characters | Pest attacked |
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A. Predators |
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Spiders 1. Wolf spider 2. Lynx spider 3. Jumping spider 4. Long jawed spider 5. Dwarf spider 6. Orb spider |
Female lays 200-800 eggs in life-time of 3-4 months. Both nymphs and adults are voracious feeders. It consumes 5-15 insect pests in a day depending up on the size. | Leaf and plant hoppers, leaf feeding caterpillars and adult stem borers. |
| Damsel and dragon flies | Multi-coloured with transparent narrow wings. Nymphs are aquatic and can climb up rice stems to search food. Adults fly normally below the rice canopy in search of flying insects. | Stem borers, hoppers and other flying insects. |
| Mirid bugs | Adults are green and black at the shoulder. Nymphs are greenish. They can consume 7-10 eggs or 1-5 hoppers a day. | Leaf hoppers and plant hoppers. |
| Water bugs | Broad shouldered adults can be either winged or wingless. Each female lays 20-30 eggs in rice stumps above the water level. Life span 1-2 months. Winged adults disburse when rice plants dry up. | Plant hopper and other small soft-bodied insects. |
| Water treaders | They are solitary feeders | Stem borer larvae and hoppers that fall on water surface. |
| Water striders | Each strider takes 5-10 prey daily. They live for 1-1.5 months, lay 10-30 eggs. | Rice hoppers, moth and larvae that drop on the water surface. |
| Ground beetle | Hard bodied insects. Larvae are shiny black and adults are reddish brown-Active predators, which pupate in the soil. Consume 3-5 larvae/day. | Plant hoppers |
| Rove beetle | 7 mm long with short elytra and blue tip of abdomen. Found on rice plant, water, ground surface and active during night. | Leaf hoppers, plant hoppers and larvae of leaf folder and hairy caterpillar. |
| Lady bird beetles | Active during daytime. Found in the upper half of rice canopy. Feed on small and slow moving prey as well as on exposed eggs. Grubs are more voracious than adults and consume 5-10 prey. Produce 150-200 offsprings in 6-10 weeks. | Plant hoppers |
| Crickets, Sword tailed crickets | Egg predators | Eggs of stripped borer, leaf folder, army worm and nymph of plant hoppers and leaf hoppers. |
| Grasshoppers, Meadow grass hoppers | Distinguished from true grasshoppers by its long antennae, which are more than twice as long as its body length. Active at night and abundant in older fields. Can consume 3-4 yellow stem borer egg masses per day. | Eggs of rice bug and stem borer, nymphs of plant hoppers and leaf hoppers. |
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B. Parasites |
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| 1 Egg parasites | ||
| Trichogramma sp. Telenomus sp. Tetrastychus sp. | Dark coloured tiny insects. Female wasp lays 20-40 eggs in the host egg. Development from egg to adult stage takes 10-40 days. | Stem borers and leaf folders |
| Gonatocerus sp. Anagris sp. | Brown to dark yellowish brown tiny wasp. Females can reproduce without mating. Adults live 6-7 days and parasitise on an average 8 eggs/day. | Plant hoppers and leaf hoppers |
| 2. Larval parasites | ||
| Cotesia sp. Stenobracon sp. Macrocentrus sp. Xanthopimpla sp. Charops sp. | Dark coloured wasp. Lives for 4-7 days | Larvae feeding on stem, leaf and other parts of rice plant |
Citation:
Kerala Agricultural University. 2002.
Package of Practices Recommendations: Crops. 12th Edition
(eds. A. I. Jose et al.). Kerala Agricultural University, Trichur. 278p.