Pests on store produce

Pests on stored products

CLASSIFICATION

Internal or primary feeders:

Require whole grain for its life cycle completion

External or secondary feeders:

Spend its life cycle outside the grain or on the finished / processed food

Beetles, weevils and moths are the common insect pests of stored grains/ seeds.

A.INTERNAL FEEDERS

Rice weevil

Lesser grain borer

Cigarette/ Tobacco beetle

Drug store beetle

Pulse beetle

Tamarind/ Groundnut Bruchid 

Coffee bean weevil

Angoumois grain moth

Sweet Potato weevil

Potato tuber moth

B. EXTERNAL FEEDERS

Khapra beetle

Red flour beetle, Confused flour beetle

Saw toothed grain beetle

Rice moth

Fig / Almond/ Warehouse moth

Indian meal moth

1. Rice weevil, Sitophilus  oryzae, S. zeamais, S. granaries : Curculionidae : Coleoptera.

Host range: Wheat, rice, maize, cholam, paddy .

Nature of damage: Both grub and adult cause the damage. Grains are hollowed out.

Adult: Small, reddish brown with four pale spots on the elytra .

2. Lesser grain borer: Rhyzopertha dominica, Bostrychidae, Coleoptera

Grub: White apodous with brown head. 

Adult: Dark brown beetle with head bent under the thorax and the posterior abdominal end blunt. 

Presence of round tunnel (1 mm) in grains and root crops.

3. Cigarette beetle: Lasioderma serricorne, Anobiidae, Coleoptera

Grub: Whitish hairy grub.

Adult: light brown round beetle with its thorax and head bent downward;
gives the insect a humped appearance. 

Circular, pin head sized bore holes on processed tobacco, wheat flour, cereal

bran, peanuts, cocoa beans, cotton seed, spices and even insecticides

containing pyrethrum, meat and fish meal, ginger, turmeric and chillies.

4. Drug store beetle: Stegobium paniceum:Anobiidae:Coleoptera.

Grub: Similar to cigarette beetle but not hairy.

Adult: Reddish brown small beetle with striated elytra and clubbed antenna. 

Circular pin-head sized bore hole on turmeric, coriander, ginger, dry vegetable and animal
matter.

5. Pulse beetle: Callosobruchus maculatus (chinensis), Bruchidae, Coleoptera.

6. Sweet potato weevil: Cylas formicarius: Apionidae: Coleoptera.

7. Angoumois grain moth: Sitotroga cerealella:Gelechiidae:Lepidoptera.

Adult: yellowish moth with pale forewings and uniformly grey; pointed hindwings with fringes of hairs.

Exit holes of 1 mm diameter with or without a trap door on the affected cereal

grains especially of paddy, sorghum, maize, wheat, barley before harvest and

also in store.

8. Khapra beetle: Trogoderma granarium :Dermestidae:Coleoptera.

Adult: reddish brown beetle.

Seed coat chewed up in an irregular manner on all cereals especially wheat,

wheat products, oil cakes and peanuts.

9. Potato tuber moth: Phthorimoea operculella, Gelechiidae, Lepidoptera.

10. Red flour beetle: Tribolium castaneum: Tenebrionidae: Coleoptera.

Adult: reddish brown, flat small beetle having eleven segmented antenna with a

feebly differentiated club of 5 segments.

11. Indian meal moth: Plodia interpunctella:Phycitidae:Lepidoptera.

Adult: Brown colored moth with a white band on forewings. 

Dense webbing on the surface of affected products like dried fruits and 

vegetables cereals especially maize, farinaceous products, nuts and sweets.

12. Fig moth: Ephestia (=cadra) cautella: Phycitidae:Lepidoptera.

13. Rice moth: Corcyra cephalonica :Galleriidae:Lepidoptera.

Adult: moth with pale-yellowish green forewings and grey white hind wings.

Dense webbing on peeled rice, maize, other cereals, milled products, cocoa

beans, peanuts, cotton seeds and raisins.

Rice Moth

14.  Saw-toothed grain beetle Oryzaephilus surinamensis : Silvanidae: Coleoptera.

Adult beetle is slender and brown much flattened beetle with row of saw like sharp teeth on either side of prothorax.

Saw-toothed grain beetles attack mainly the starchy food items in flour mill and grocery stores. It feeds on rice, grain products, dry fruits, nuts, seeds, yeast, sugar, candy, tobacco, snuff, dried meat, processed plant materials.