BP Singh

Symptoms of Insect Damage in Crops 177Flower and bud feedersAdult blister be.e.tles (Meloidae) chew the petals of manyplants. Adult flower h.eg.t~~s (Scarabaeidae) m~~.§_m.ajL~21~~ inthe .£.~.~ls. l:hriz;?s, both ad.!!lts and nymp}1s, scarify the bases of~ls. Tiny black beetles make feeding scars at the base of thepetals. Flower deformation is caused by ~DlQggQ.ts as gall midgelarvae. Caterpillars of some Tortricidae bore into the large buds.Large caterpillars as semi-loopers feed on the flowers by makinglarge holes. Maruca testulalis, webs together the flowers and budsand feeds on the opening buds thus causing reduction in seedproduction. Gall mites of family Eriophyidae infest buds of someplants and cause a disorder called 'big bud'.Fruits feedersThe fruit flies, fruit worms and wepvils cause considerabledamage to different fruits. The fruit flies of family Tephritidaeattack almost all larger types of fruits. They puncture the fruitsurface for oviposition. The larvae develop internally as the fruitripens by feeding on the pulp resulting in fruit rot with visiblebrown patches on the exterior. The infested fruits fall prematurely.The color of rotting patch is brownish in citrus, mango, apple,peach, apricot and black in penr and banana. The green fruit wormcauses large, irregular cavities in immature apples which at the. time of feeding look deformed, with brown disks on healed overcavities. The grubs of walnut weevil Alcidodes porrectirostris, boreinside the fruit and feed on the kernel turning it to a black mass.The pomegranate fruit borer, Virachola isocrates, caterpillars boreinto the fruit and feed on its internal contents. Characteristicallythe anal segment of the caterpillar is often seen plugging the borehole. Some heteropteran bugs of families Miridae, Coreidae andPentatomidae have toxic saliva which causes necrosis at thefeeding site on fruits. This usually becomes infected with fungiand bacteria resulting in rotting, death and premature fruit fall.Bark feedersA considerable number of insect species damage the bark ofthe host and make different forms of galleries on the trunk andtwigs. The branch or whole tree may die by feeding of larvae insidE"and girdling of the bark. Termites also cause damage to the barksof plantation crops and forest trees. Q!u~s of Xyloborus perforans