Agricultural Entomology - Study Mode

[#331] Leaf gall forming thrips, Liothrips karnyi is a pest of
Correct Answer

(B) Black pepper

Explanation

Solution: Leaf gall-forming thrips, Liothrips karnyi is a pest of Black pepper. Marginal gall thrips are scientifically known as Liothrips karnyi. Both nymphs and adults feed on leaves and cause the formation of marginal folded galls on them. The presence of white or creamy white nymphs and adults inside the marginal galls is the typical symptom of attack. In severe cases of attack, whole plant becomes stunted and affecting the formation of spikes.

[#332] Pyrilla belong to the family
Correct Answer

(B) Fulgoridae

Explanation

Solution: Pyrilla belongs to the family Fulgoridae. Pyrilla perpusilla, commonly known as the sugarcane planthopper, is a planthopper in the family Lophopidae. It is native to Asia where it feeds on grasses and other plants and is a major pest of sugarcane and sorghum. The planthopper feeds on its host by inserting its stylet into a leaf and sucking out the phloem sap. Excess fluid is excreted as honeydew and sooty mould grow on it. The plant's vigour is reduced through the loss of sap and the reduction in photosynthesis resulting from the sooty mould.

[#333] White parallel streaks along leaf axis in rice is a characteristic symptoms of
Correct Answer

(B) Dicladispa armigera

Explanation

Solution: White parallel streaks along leaf axis in rice are a characteristic symptom of Dicladispa armigera. The characteristic symptoms of its damage are presence of parallel white streaks on the surface of infested leaves towards the tips. Adult beetles feed externally on the upper epidermis, causing a characteristic pattern of white, parallel streaks along the main axis of the leaf. In case of severe infestation, even the veins can be affected, leading to the appearance of large, white blotches.

[#334] In plants and mosquito larvae DDT is converted to
Correct Answer

(A) DDD

Explanation

Solution: In plants and mosquito larvae DDT is converted to DDD. Dichlorodiphenyltrichloroethane, commonly known as DDT, is a colorless, tasteless, and almost odorless crystalline chemical compound, an organochloride. DDE and DDD form when DDT breaks down. These chemicals can evaporate into the air from water and moist soil and may then be carried to locations very far from the source. They can be removed from the air by rain and snow or be broken down by sunlight.

[#335] GEP of the pest coincides with ETL, then the pest belongs which category?
Correct Answer

(B) Major pest

Explanation

Solution: GEP of the pest coincides with ETL, then the pest belongs major pest category. The economic threshold Level (ETL) is the population density at which control measures should be determined to prevent an increasing pest population from reaching the Economic injury level. EIL is the lowest pest population which will cause economic damage. These are pests with the population crosses EIL quite frequently and require repeated control measures to avoid economic damage, The Damage is >10%. GEP lies very close to EIL or coincides with EIL e.g. Cotton jassid, Rice stem borer.