BP Singh

174 Shashi BlzallaJassids : Commonly called ~~~LhgpE~X~' They suck the juices fromveins and veinlets mainly from th,e undersurfaces "Of leaves whichbecome brown, tum upwards and dry out in cases of severeinfestatio;t:-thls feeding causes c;hlQro.ti~.lines parallel to the veinsand plants become ~u.JJ.ted..Scales : ~(}YE:!r the tender k_a;yes and shoots and $ck th~ _sap. Sootymould development is commonly noticed, e.g., G:re,en scale Coccus1!iridis on coffee.Pest darnage is probably most conveniently consideredaccording to the part of the plant body attacked as damaged leaves,f1OW~,rs and..buds, {nuts, stems, r.Qots, tubers and s.eed~.Foliage feedersThe insects feed on the plant tissues from outside. This groupincludes grasshoppers, beetles, weevils, their' grubs and manycaterpillars, e.g., armyworms, hairy caterpillars, cutworms etc.The leaves ~ay be eaten to different extents thus causing reductionin the assimilative area of the leaf.The leaves could be eaten from edges (i) with regular notches(Curculionidae), (ii) with semicircular pieces of lamina missing(adults of leaf cutting ants) and (iii) with irregularly eaten out areas(grasshoppers, locust). The leaf lamina is damaged to differentextents ranging from windowed lamina (Diamond back moth),holed lamina (adult flea beetles, Chrysomellidae) to skeletonizedlamina (Epilachna, citrus flea beetles etc.). The rice hispa,DichZadispa armigera scrapes the upper surface of leaf blade andleaves intact the lower epidermis. Leaf curled under or generallydistorted, sometimes completely distorted into a bunchy lump oftissue is the characteristic damage by the sucking pests. Adults andnymphs of some thrips make tiny epidermal feeding lesions whichgive the lamina a silvery, bronzed or scarified appearance. Leavesare also damaged by the galls either on upper or lower surface,sometimes arranged randomly, distributed peripherally or alongthe side veins. These are made by the feeding larvae of gall midges,gall wasps and some psyllids.Leaf webbersMany ~Sl ~tles and ~es form webs on 1~.They roll up the leaves by binding the edges with strands of silk