Major Pests and Diseases of Rice (Oryza sativa)
Major Insect Pests of Rice
Pest Name | Scientific Name | Damage Symptoms | Season/Condition |
Rice Stem Borer | Scirpophaga incertulas | Dead heart in vegetative stage; White ear head in reproductive stage | Kharif & Rabi; high humidity |
Brown Plant Hopper (BPH) | Nilaparvata lugens | Hopper burn (dry patches), stunted growth | High humidity; excessive nitrogen |
Green Leaf Hopper (GLH) | Nephotettix virescens | Transmits Tungro virus; yellowing of leaves | Rainy season |
Rice Hispa | Dicladispa armigera | Scraping of leaves; reduced photosynthesis | Post-monsoon |
Major Diseases of Rice
Disease Name | Causal Organism | Symptoms | Favorable Condition |
Blast (Leaf/Neck) | Magnaporthe oryzae | Spindle-shaped lesions; neck rot | High humidity; low temperature |
Bacterial Leaf Blight | Xanthomonas oryzae pv. oryzae | Yellowing, wilting, water-soaked streaks | Warm, humid condition |
Sheath Blight | Rhizoctonia solani | Irregular lesions on leaf sheath | Dense canopy; high N-use |
Sheath Rot | Sarocladium oryzae | Rotting of sheath with dirty patches | High humidity |
Tungro Virus Disease | Rice tungro bacilliform virus | Yellow-orange leaf color; stunted growth | Transmitted by GLH |
False Smut | Ustilaginoidea virens | Greenish balls (smut balls) on panicle | Humid condition post-anthesis |
Brown Spot | Bipolaris oryzae | Brown circular spots with yellow halo | Poor nutrition, seed-borne |
Major Pests and Diseases of Wheat (Triticum aestivum)
Major Insect Pests of Wheat
Pest Name | Scientific Name | Damage Symptoms | Season/Condition |
Termites | Odontotermes spp., Microtermes spp. | Wilting, hollow roots and stems | Moist warm soil |
Shoot Fly | Atherigona naqvii | Dead heart in seedlings | Early sown wheat |
Pink Stem Borer | Sesamia inferens | Dead heart, bored stems | Common in warm areas |
Aphids | Rhopalosiphum maidis, Sitobion avenae | Sap-sucking; reduced vigour; sooty mold | Cool and humid season |
Major Diseases of Wheat
Disease Name | Causal Organism | Symptoms | Favorable Condition |
Rusts (Three types) | |||
– Yellow Rust (Stripe) | Puccinia striiformis | Yellow stripes on leaves | Cool and moist |
– Brown Rust (Leaf) | Puccinia triticina | Brown pustules on leaves | Moderate temperature |
– Black Rust (Stem) | Puccinia graminis tritici | Elongated black pustules on stems and leaves | Warm temperature |
Powdery Mildew | Erysiphe graminis f.sp. tritici | White powdery patches on leaves and stems | Cool, humid conditions |
Karnal Bunt | Neovossia indica | Partial blackening of grains; fishy odor | Cool & humid during anthesis |
Loose Smut | Ustilago tritici | Black, powdery spores in place of grains | Systemic; seed-borne |
Alternaria Leaf Blight | Alternaria triticina | Brown concentric spots on leaves | Late season; moist condition |
Flag Smut | Urocystis agropyri | Twisting of flag leaf; black streaks | Low temperature |
Fusarium Head Blight | Fusarium graminearum | Bleaching of spikelets; pink mold on grains | Wet and warm flowering period |
