Download Identification, Symptoms and nature of damage of Helicoverpa

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 AugustNovember.
• 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
Skeletonization
Scrabbing of leaves
Courtesy:
www.projectnoah.org
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.
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.
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.