Agricultural Entomology - Study Mode
[#121] Nibbling of rice earhead and defoliation leaving midrib in rice is caused by
Correct Answer
(A) Hieroglyphus banian (rice grass hopper)
Explanation
Solution: Nibbling of rice earhead and defoliation leaving midrib in rice is caused by Hieroglyphus banian (rice grass hopper). Rice grasshopper is an important pest of rice. It causes heavy damage to nurseries and reduces yield. Adults are about the size of your little finger. The body is a shiny greenish yellow colour with three black lines on its upper side.
[#122] Silk gland is a modified part of labial gland and . . . . . . . . in origin.
Correct Answer
(A) Ectodermal
Explanation
Solution: Silk gland is a modified part of labial gland and Ectodermal in origin. In lepidopteron larvae, the silk thread of the cocoon is secreted by a pair of silk glands which are modified labial glands. Silk gland is ectodermal in origin and lies on the lateral side of the gut.
[#123] Sudden trapping is used for
Correct Answer
(B) Collembola
Explanation
Solution: Sudden trapping is used for Collembola. Insect traps are used to monitor or directly reduce populations of insects or other arthropods, by trapping individuals and killing them. Collembola form the largest of the three lineages of modern hexapods that are no longer considered insects. Collembolans are omnivorous, free-living organisms that prefer moist conditions. They do not directly engage in the decomposition of organic matter but contribute to it indirectly through the fragmentation of organic matter and the control of soil microbial communities.
[#124] Number of nymphal stages is Acarina is
Correct Answer
(D) 3
Explanation
Solution: Number of nymphal stages is Acarina is 3. The order Acarina, including mites and ticks, contains numerous economically and medically important species that are parasitic on humans, domesticated or hunted animals, and crops, food, etc. The Ixodidae may have only one nymphal stage, while the Argasidae may have as many as eight. Some Prostigmata develops directly from egg to larviform adults, while others have from one to three nymphal stages.
[#125] Ctenidia is found in the order
Correct Answer
(B) Siphonoptera
Explanation
Solution: Ctenidia is found in the order Siphonoptera. The order Siphonaptera, includes 2,500 species of small flightless insects that live as external parasites of mammals and birds. A ctenidium is shaped like a comb or a feather, with a central part from which many filaments or plate-like structures protrude, lined up in a row. It hangs into the mantle cavity and increases the area available for gas exchange.