Agricultural Entomology - Study Mode

[#286] How much resin is found in lac insect?
Correct Answer

(B) 68%

Explanation

Solution: Resin found in lac insects is 68%. Lac is the resinous secretion of several species of lac insects. Lac is harvested by cutting the tree branches that hold sticklac. If dye is being produced, the insects are kept in the sticklac because the dye colour comes from the insects rather than their resin. Thousands of lac insects colonize the branches of the host trees and secrete the resinous pigment. The coated branches of the host trees are cut and harvested as sticklac.

[#287] Which one of the following formulations of a pesticide would be most suitable for spraying in a standing crop of rice?
Correct Answer

(A) Endosulfan EC

Explanation

Solution: Endosulfan EC formulations of a pesticide would be most suitable for spraying in a standing crop of rice. Endosulfan is an off-patent organochlorine insecticide and acaricide that is being phased out. It became a highly controversial agrichemical due to its acute toxicity, potential for bioaccumulation, and role as an endocrine disruptor. Endosulfan has been used in agriculture around the world to control insect pests including whiteflies, aphids, leafhoppers, Colorado potato beetles and cabbage worms.

[#288] Highly evolved insect order is
Correct Answer

(A) Hymenoptera

Explanation

Solution: The highly evolved insect order is Hymenoptera. Hymenoptera is a large order of insects, comprising the sawflies, wasps, bees, and ants. The name Hymenoptera refers to the wings of the insects, but the original derivation is ambiguous. In the more ancestral hymenopterans, the ovipositor is blade-like and has evolved for slicing plant tissues. In some species, the ovipositor has become modified as a stinger, and the eggs are laid from the base of the structure, rather than from the tip, which is used only to inject venom.

[#289] Scientific name of banana aphid is
Correct Answer

(B) Pentalonia nigronervosa

Explanation

Solution: Scientific name of banana aphid is Pentalonia nigronervosa. Pentalonia nigronervosa (banana aphid) is an aphid in the superfamily Aphidoidea in the order Hemiptera. It is a true bug and sucks sap mainly from Musa species. Banana bunchy top disease is one of the most serious diseases of bananas. The disease is caused by Banana bunchy top virus (BBTV), which is transmitted by banana aphids (Pentalonia nigronervosa Coquerel).

[#290] Which is a pro-insecticide?
Correct Answer

(D) All of these

Explanation

Solution: Pro-insecticide is Padan, Cartap and Thiocyclam. A compound that, on administration, must undergo chemical conversion by metabolic processes before becoming the pharmacologically active insecticide is a proinsecticide. Padan is a systemic insecticide highly effective against chewing, sucking and boring insects. It is registered for use in rice, crucifiers, cucurbits, onion, potato and mango. Cartap [S,S ′-(2-dimethylaminotrimethylene)- bis(thiocarbamate)] is a pesticide that was first introduced in Japan in 1967 and has been commonly used to control weeds and caterpillars.
Thiocyclam hydrogen oxalate (Evisect) is a broad-spectrum synthetic insecticide used to control the sucking and chewing pets on a variety of crops.