22 Apr Insect and pests of stored grains and their management
संग्रहित अनाज के कीट-पतंग तथा उनका प्रबंधन Global loss in stored products, caused by insects, have been estimated to be between five and ten percent. In the tropics it may reach upto 30%. Insects not only cause direct loss through consumption of kernels but also indirect losses which includes accumulation of frass, exuviae, webbing and insect cadavers. High levels of this insect detritus may result in grain that is unfit for human consumption. Storage insect pests are categorized into two types viz., 1. Primary storage pests Primary storage pests are those capable of penetrating and infesting intact kernels of grain, and have immature stages that can readily develop within a kernel of grain. Insect Family : order Damaging stage Damage symptom Images Rice weevil Sitophilus oryzae Curculionidae: Coloeoptera Grubs and adults Grubs feed inside, grains are hollowed out and in some cases the kernels are reduced to powder. Adults make irregular holes on the grains. Adult weevil Khapra beetle Trogoderma granarium Dermestidae: Coleoptera Grubs Grubs mainly attacks the grains of wheat, maize, sorghum, pulses and oil seeds. Grubs remain on the top few layers of the bulk grains Grub Pulse beetles Callosobruchus chinensis C. maculatus C. analis Bruchidae: Coleoptera Grubs Individual eggs are laid on pulses by adult beetle and the emerging grubs feed on the inner contents and pupates inside the grain Egg and Adult Cigarette beetle Lasioderma serricorne Anobiidae: Coleoptera Grubs and adults Grubs and adults feed on stored tobacco, turmeric, chillies and...