Introduction Grape is the second most widely grown commercially important fruit crops of the world after olive. It is grown in varied climatic conditions ranging from temperate to semi tropic and tropics. Insect pests represent a major threat to the commercial production of grapes. Insects feeding on grapevine leaves, roots, flowers / berries and shoots are the most destructive (like flea beetle, berry borers, leaf eating caterpillars and leaf rollers).

1. Grape berry borer Helicoverpa armigera Noctuidae, Lepidoptera Incidence of berry borer is sporadic and reported as minor pest status in grape cultivation. Caterpillars feed on grapevine leaves voraciously. Popularly, the insect is known as berry borer because it feeds on berries by boring during Oct- Dec.

Symptoms of damage Feed on berries Partly eaten fruits in the bunch of berries Rotting occur due to secondary infestation

Identification Eggs are spherical in shape and creamy white in colour, laid singly. Larva shows colour variation from greenish to brown. Green with dark brown grey lines laterally on the body with lateral white lines and also has dark and pale bands. Pupa brown in colour, occurs in soil, leaf, pod and crop debris. Adult - light pale brownish yellow stout moth. Forewing grey to pale brown with V shaped speck. Hind wings are pale smoky white with a broad blackish outer margin Courtesy: www.insectimages.org

2. Tobacco Caterpillar, Spodoptera litura Noctuidae, Lepidoptera This pest is of common occurrence in Maharashtra and Hyderabad. Symptoms of Damage: Young larvae feed on the lower epidermal layer of the underside of the leaf and make the leaf surface papery. The larvae of the pest also feed on the leaves and inflorescence. They cut down the rachis of the grape bunches. The adult moths are most active during August-September.

Identification The adult moth lays eggs in clusters of 200-300 on the lower side of the leaves and covered with brown scales. The larva is brownish in colour with three thin lines running along its sides. They feed in a group when they are young but spread out as they get older. They undergo pupation in the soil. The life cycle takes about 25 days. Courtesy: www.insectimages.org

Management of berry borer and Tobacco caterpillar Hand picking of well grown larvae and destroy them. Caterpillars can be effectively controlled by spraying of Chlorpyrifos (0.08%) or Carbaryl (0.125%) or Dichlorvos (0.1%). A mixture of Methomyl (0.05%) and Wettable Sulphur (0.2%) is effective to control the larvae in its young stage of growth. Use of pheromone traps is effective in catching the adult moths and also to know the population built up of the pest.

3. Grape Leaf Roller Sylepta lunalis Noctuidae, Lepidoptera This is a serious pest in South India, which is most active in the months of August-November. In case of severe infestation complete defoliation is observed

Leaf roller, Sylepta lunalis Symptoms of damage Yellowish-green caterpillars roll the leaves from the edges towards the midrib and feed within. Scrabbing the chlorophyll content inside the leaf roll. Skeletonization of  leaves. Rolling of leaves Courtesy: www.projectnoah.org Skeletonization Scrabbing of leaves

Identification Larva - Pale green with short hairs. Adult - Brownish moth with wavy line. Management: Simple method to control the pest population is to collect and burn the infested leaves. Spraying of Malathion (0.05%) or Endosulphan (0.05%) have been recommended for effective control of the pest.

It is the most destructive pest of grapevine all over India. 4. GRAPEVINE FLEA BEETLE Scelodonta strigicollis Chrysomelidae: Coleoptera It is the most destructive pest of grapevine all over India. In north India, the beetles start their activity mainly from May onwards, though they are seen scraping the sprouting buds in early March. In south and west India, the emergence of the beetle synchronises with the pruning season. The adults are very destructive during Sep - Nov particularly when the vines put forth new flush after pruning.

Complete fed sprouting buds. Symptoms of damage The beetles feed on the sprouting buds and eat them completely without allowing them to develop. They feed on mature leaves cutting elongated holes on the leaf lamina like shot holes. The damage results in Complete fed sprouting buds. Shot holes (rectangular cuttings) on mature leaves. The pest also attacks roots, tendrils, mature leaves. Shot holes  Courtesy: nrcgrapes.nic.in

Identification of the Pest Adult - Reddish brown, shiny with six spots on elytra. Grub – brown in colour and black colour head. The females lay eggs about one month after emergence and continue from middle of March to middle of October. Eggs are laid beneath the bark in groups of 20-40. Egg period is 4 days. On hatching small, dirty white grubs drop down to the water basin and burrow into the soil and feed on the cortical layer of roots not causing any appreciable damage. Larval period is 6 -7 weeks. Larva Adult Courtesy: TNAU agriportal

Management Remove the loose bark at the time of pruning and rub the stems with jute to remove the egg masses. Put bundles of dry shreds of banana on the pruned end of the vines in the evening. Beetles, which take shelter on these at night, can be shaken and collected in the morning and kill them. Shake vines to dislodge adult beetles. Collect into trays containing kerosenated water and destroy them. Spraying with Carbaryl 50 WP @ 2 ml/l or Imidacloprid 200 SL @ 0.3 ml/l are recommended to control this pest.

Let’s sum up Insect pests represent a major threat to the commercial production of grapes. Caterpillars of Helicoverpa feed on grapevine leaves voraciously. Spodoptera larva feed on the leaves and inflorescence and also, cut down the rachis of the grape bunches. The adults of flea bettles are very destructive particularly when the vines put forth new flush after pruning. Timely monitoring and proper management practices enable to protect the crop from heavy loss due to insect pests.