Rice weevil Assignment

Submitted To :- Submitted By :- Dr. O. P. Chaudhary Vaibhav Dept. of Entomology

Rice weevil

Common Name - Ghun, killa, Ghanera, Sund wali sursuri.

Systematic Position:- Scientific Name - Sitophilus oryzae Order - Coleoptera Family - Curculionidae

Status – most destructive pest of stored grains.

Rice weevil

Hosts :• Rice•Wheat• Maize

•Jowar• Barley• Other food grains and processed food.

Distribution : The pest is world wide and found particularly throughout India.

wheat Rice

Maize

Biology :-Eggs – • Laid singly• Translucent white in colour.• Arround 0.7mm long and 0.3mm broad. • It makes a cavity in the grain, lay eggs and plugs the hole with secreted material

from ovipositor.

Grubs –• Tiny legless• White body with yellowish brown head• Plumpy, fleshy creature• Full grown grub is 5mm in length.

Rice weevil

Pupa –• Pupate inside the grain.• At first, the pupa is dirty white, but later become dark brown.

Adult –• Small reddish brown beetle with a long snout.• 3mm in length having cylindrical body.• Meta thoracic wings are well developed. • Elytra bears four light reddish or yellowish spots.

Rice weevil

Life Cycle :-

• Female starts laying eggs after 4-5 days of emergence.

• Breeds from april to oct.• Hibernates as adult in winter inside

cracks and crevices.• Fecundity – 400 eggs/female• Adult lives for about 4-5 months.• Generally 5 generations in a year.

Rice weevil

Rice weevil family pic :

Rice weevil

Damage :-Nature –• Both grub and adult cause damage.• Break and hollow the grain.• Grubs are more destreuctive than adults.• Attacks in field too.

Rice weevil

Extent of damage –

• Affected grains become unfit for human consumption.• Damage is both quantitative and qualitative.• In north India, the greatest damage is caused from july to nov.• In India, the loss to stored grains by this pest alone is valued at many crores of rupees every year.• In case of severe infestation only fragments of pericarp with frass are left behind.

Rice weevil

Rice weevil severe damage -

Natural enemies :-

Egg parasite – Acarapsis doctamite

Grub parasite – • Larrophagous ditinguenduss• Aplastomorpha calanae• Pendiculeides ventricosis (mite)

Rice weevil

Thank you