BP Singh

IISymptoms of Insect Damage in CropsShashi BhallaIntroductionThe struggle between wan and insects began long before thedawn of civilization. I.nse_S~s are most numerous m~mbers ofanimal kingdom, which is attributed to their s;naU size, widea£laptab.ility and s!lperior body structure. About lQI.QQO of the640,000 species of insects are injurious to plants and of these about-?Q9pm be considered as 1!);ajor pests in India. Annual losses dueto insect pests have been estimated to about p per cent. No otherclass of animals is so intimately involved in the intric~cies andcomplexities of the biological world as are insec;ts.Extent of insect injuryInsects have been found associated with all the plant partsi.e. leaves, flowers, fruits, buds, seeds, bark, wood and roots. Infact,~;o pla;},t part is free from their damage. Nearly all the injurydone by insects results directly or indirectly from their attempt tosecure food. ¥any insE;!cts are physically observed on the _Rlantsbut q_the!s are I10ctumal in their :v.£lbit and they .J:rlde under ~oilclods, fallen leaves or bark crevices during the day time. Thoughthey may not be visible during the day time, they causeconsiderable damage to the crops.An insect or a group of insects produces specific symptomsof damage by ~egtng or o_vipositing activities. Therefore, it isessential for a pJa.p...! l:>r~~der or ,plant explorer to be acquainted with