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JRF Horticulture

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

 

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