A decision to use an insecticide should be made only when an insect population has reached or exceeded an economic threshold—that level of a pest population at which control is needed to prevent economic loss (that is, the projected cost of damage is greater than the cost of control).The utmost principles of an insect management program are scouting fields and basing control decisions on economic thresholds. Growers should incorporate scouting and the use of economic thresholds into their crop management plans. Economic thresholds of insect pests of General Crops, Vegetables & Orchards are given as under:
Cotton
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Jassid
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1 Adult or Nymph per leaf
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Whitefly
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5 Adult or Nymph or both per leaf
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Thrips
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8-10 Adult or Nymph per leaf
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Cotton Mealy Bug
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On Appearance
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Mites
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On Appearance
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Spotted Bollworm
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3 Larvae/ 25 plants
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Pink Bollworm
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5 Larvae/ 100 Bolls
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American Bollworm
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5 Brown eggs or 3 small larvae or Both 5 / 25 plants
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Armyworm
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On Appearance
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Aphid
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Visible Damage on top terminals
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Dusky Cotton Bug
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10 per leaf/bud
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Diseases
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On Appearance
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Rice
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Nursery
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Borers
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0.5% attack on rice nursery while 4-5 moths/trap/night
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Toka
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3 per net on rice nursery
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Crop
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Borers
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8-10 Moths/Trap/Night
Dead Hearts 5 %
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Chrotogonous (Toka)
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5 Adults/Net
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Leaf Folder
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2 rolled leaves per plant (July-Aug)
3 rolled leaves per plant (Sep-Oct)
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White Backed plant Hopper/Brown Plant Hopper
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15 nymphs or adults per plant/7-10 nymphs or adults per net (July-Aug)
20 nymphs or adults per plant/7-10 nymphs or adults per net (Sep-Oct)
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Hispa
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1 per plant
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Diseases
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On Appearance
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Wheat
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Diseases
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On Appearance
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Armyworm
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On Appearance
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Aphid
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25/ tiller
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Pink Graminous borer
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5% damage
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Narrow Leaf Weeds
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Phalaris minor (Dumbi Sitti)
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4/sq.m
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Avena fatuae (Jungli jae)
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4/sq.m
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Broad Leaf Weeds
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25/Sq.m.
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Sugarcane
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Top Borer
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10% Attacked Plants
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Stem Borer
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-do-
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Root Borer
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-do-
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Gurdaspur Borer
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-do-
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Pyrilla
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2/Leaf
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Black bug
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10/ sheath
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Whitefly
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10/ Leaf
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Mites
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10/ Leaf
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Toka
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3/ Sweep of Net
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Mealy Bug
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On Appearance
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Termites
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10% Damage
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Diseases
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Only Presence
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Maize
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Shoot fly
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5% damage
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Stem borer
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5% damage
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Helicoverpa
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5 % damaged Cobs
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Armyworm
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On Appearance
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Termite
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10% damage
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Aphid
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5/leaf
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Jassid
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5/leaf
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Diseases
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On appearance
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Potato
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Aphid
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3/leaf
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Jassid
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3/Leaf
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Whitefly
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10/leaf
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Helicoverpa armigera
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5% infestation
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Armyworm
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On Appearance
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Diseases
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On Appearance
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Sesame
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Leaf Webber
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8-10% damage on plants
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Whitefly
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5 nymphs or adults/leaf
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Jassid
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1 nymph or adult/leaf
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Mirid Bug
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6 per plant
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Mealy bug
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On Appearance
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Thrips
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5 nymphs or adults/leaf
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Termite
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5% Damage
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Diseases
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On Appearance
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Vegetables
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Armyworm
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On Appearance
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Diamond Back Moth
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3/ Leaf (Cabbage)
1 larva per plant (Cauliflower)
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Whitefly
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5 nymphs or adults/Leaf (Cucurbits, Crucifers)
2 nymphs or adults /Leaf (Chillies, Legumes)
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Red Pumpkin Beetle
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1/ Plant (at seedling stage)
2/ Plant (at crop stage)
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Fruit Borer
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10% on Brinjal 5% on Tomato
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Hudda Beetle
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4/ leaf
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Helicoverpa
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5% Fruit Infestation
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Fruit Fly
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3 % Fruit Infestation
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Jassid
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1/Leaf on Cucurbits,
2/ Leaf on Brinjal,
3/ Leaf on Melons
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Aphid
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5/Leaf
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Semilooper
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3 per 25 plants
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Cabbage butterfly
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2 per 10 leaves
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Thrips
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10 per leaf
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Mites
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10 per leaf
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Mealy Bug
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On appearance
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Spotted Bollworm
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3 larvae per 25 plants
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Cutworm
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4% damage
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Leaf miner
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10% affected leaves
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Termite
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10% damage
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Stem borer
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5% damage
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Diseases
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On appearance
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Fodder (Sorghum, Millet, Lucern, Berseem)
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Borer
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5% damage
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Helicoverpa
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5% spikes/ affected beans
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Spotted Bollworm
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On Appearance
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Termite
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10% damage
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Mites
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10/leaf
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Aphid
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5 per leaf
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Semilooper
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5 larvae per sq.meter
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Diseases
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On Appearance
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Pulses
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Spotted Bollworm
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On Appearance
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Armyworm
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On Appearance
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Helicoverpa
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3 Larvae/25 plants
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Termite
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10% damage
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Cutworm
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10% damage
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Toka
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3-5 per net
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Pod Borer
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5 larvae/Sq. M
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Disease
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On Appearance
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Mango
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Hopper
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5/ Leaf (In Summer) or 10 inflorescence or Twig
1/ Leaf (In Winter) or 10 inflorescence or Twig
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Scales
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50 Scales / Leaf
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Fruit Fly
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10% Damage
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Termite
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10% Damage
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Borer
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5% Damage
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Mealy Bug
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On Appearance
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Gall Farming Insect
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10 Galls / Leaf
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Disease
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On Appearance
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Citrus
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Citrus Psylla
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6/ Leaf
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Whitefly
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10/leaf
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Scales
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50/leaf
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Aphid
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5/leaf
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Leaf miner
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10% affected leaves
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Lemon Butterfly
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2 larvae (5 eggs/plant)
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Fruitfly
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10% affected fruits
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Diseases
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On Appearance
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Tobacco
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Cutworm
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3% Attacked Plants
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Aphid
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50/leaf
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Jassid
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3/leaf
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Budworm
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3 larvae/25 plants
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Armyworm
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On Appearance
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Diseases
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On Appearance
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Guava
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Fruit Fly
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10% Attacked Fruits
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Mealy Bug
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On Appearance
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