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PEST OF RICE, MAIZE, WHEAT, GREEN GRAM

AND COTTON

Presented

by :

Deepanshu

Uid :

Bsc

Agriculture

th

year

Pest of Rice

Green leafhopper. Nephotettix virescens, N. Nigropictus and N. Cincticeps (Cicadellidae: Hemiptera) Egg-female inserts200-300 eggs in batches of 8-16 in midrib of leaf blade. Egg period 6-7 days, Nymph-Nymph passes through 5 instars, becomes adult in about 18 days and it takes about 24 days to complete the life cycle. Adult- N.nigropictus is about 5 mm long and possesses two black spots in the maleswhich extend up to the black distal portion of the forewings N. Virescens can be easily distinguished by the black spots in the male notex tending up to black distal portion of forewings and the absence of black tinge on the pronotum and black band on the

Damage symptoms

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 disease

Rice earhead bug: Leptocorisa acuta (Alydidae: Hemiptera) Eggs are laid in single or double rows close to midrib on the upper surface of leaves @ 10-20 per cluster. Each female lays about 100 eggs. Dark reddish brown egg is boat shaped. Egg hatches in about 7 days. Nymphs are pale yellowish green possessing odoriferous glands on the fifth abdominal segment. Nymph passes through 5 instars in about 15- 21 days. The total life cycle takes about a month. After the harvest of rice, the bug over- winters in millets and wild grasses. The adult is active, diurnal, e ventrally green measuring

Damage symtoms Both nymphs and adults suck juice from grains in milky stage, also from peduncle, leaves and stem causing the following symptoms ■ Affected grains become shrivelled and chaffy ■ Brown spot is observed at the feeding site where sooty mould develops ■ Lower grain quality and broken grains when infested at soft dough stage adult ETL: 5 bugs/100 panicles or 1 bug/hill – flowering stage; 16 bugs/ panicles or 3 bug/hill- milky stage.

Management

1. Remove alternate host, Echinocloa from bunds and field.
2. Ensure synchronous planting on community basis in an area.
3. Use neem seed kernel extract 5% or notchi leaf powder extract 5% or Ipomoea leaf powder extract 5% or Prosopis leaf powder extract 5%
4. Dust quinalphos 1.5 D or carbaryl 10 D

spot and the anal end having tuft of yellowish hair. The male is pale yellow and the pots on the forewings are not conspicuous. Male is smaller than female

Damage symptoms 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 “whit ear”. Damage ranges from 30- 80

oviposition by the stem borer.

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

• Acephate 75 SP 666-1000 g Imidacloprid 17.8 SL 100-125 ml
• Endosulfan 35 EC 1000 ml. Quinalphos 25 EC 1000 ml
• Buprofezin 25 SC 800 ml Phosphamidon 40 SL 875 ml
• Ethofenoprox 10EC 500-750 ml
• Thiamethoxam 25 WG 100 g
• Fipronil 5 SC 1-1.5 kg or 0.
• Lambda-Cyhalothrin 2.5 EC500 ml or 5 EC 250 ml
• Fenobucarb (BPMC) 50 EC500-1500 ml

Damage symptoms 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. ET L: 8-10 Nos./hill or 20 Nos./hill when spider is present at 1 No./hill Management- 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. Crop Pests and Stored Grain Pests and Their Management
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.
7. Drain the water before the use of insecticides and direct the spray towards the base of the plants.
8. 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.

• Acephate 75 SP 665-1000 g. Fenobucarb (BPMC) 50 EC 500-1500 ml
• Methyl demeton 25 EC 1000ml
• Dichlorvos 76 WSC 350 ml
• Chlorpyriphos 25 EC 1250 ml. Ethofenoprox 10 EC 500-750 ml
• Benfuracarb 3 GR 3.3 kg Clothianidin 50 WDG 20-24 g
• Imidacloprid 70 WG 30-35 g or 30.5 m/m SC 60-75 ml or 7.8 SL 100-125 ml

Symptoms of gall midge in rice include: Galls: A prominent symptom is a silvery white, hollow tube that forms at the base of tillers. This tube is about 1 cm wide and 10–30 cm long. It’s also known as an “onion leaf” or “silvershoot”. Leaf elongation: The leaf sheaths elongate, replacing the central leaf. Stunting: The plant’s growth is stunted. Seed-head: The seed-head doesn’t develop. Withering: When adult insects emerge, the gall withers away and the shoot dies.

Leaf folder (or) leaf roller: Cnaphalocrocis medinalis (Pyralidae: Lepidoptera) Egg-The female moth lays eggs in batches of 10-12, which arearranged in linear row in the lower surface of leaves. The eggs are flat, oval in shape and yellowish white in colour. The egg period is 4-7 days Larvae – Larva is 15-20 mm long, pale green, transparent, actively moving caterpillar. The larval period is 15-20 days Pupa – It pupates inside the leaf fold. The pupa is greenish brown. The pupal period is 6-8 days Adult- The adult moth is often seen in the field during daytime. The moth is brownish with many dark wavy lines in centre and dark band on margin of wings