Agricultural Entomology - Study Mode
[#271] Type of linkage found in trehalose is
Correct Answer
(C) α-1, 1
Explanation
Solution: Type of linkage found in trehalose is α-1, 1. Trehalose is a nonreducing disaccharide in which the two glucose units are linked in an α,α-1,1-glycosidic linkage. This sugar is present in a wide variety of organisms, including bacteria, yeast, fungi, insects, invertebrates, and lower and higher plants, where it may serve as a source of energy and carbon. It has been shown in several experiments that α,α-trehalose, a disaccharide consisting of two α-glucopyranose rings connected via a (1→1) glycosidic linkage, is particularly effective at preventing membrane damage upon drying in comparison to other sugar molecules.
[#272] Minning and skeletanization of cabbage leaves are the characteristic damage symptoms of
Correct Answer
(A) Diamond back moth (Plutella xylostella)
Explanation
Solution: Minning and skeletanization of cabbage leaves are the characteristic damage symptoms of Diamond back moth (Plutella xylostella). Diamondback moth larvae feed on cole crop leaves between the large veins and midribs. They prefer to feed on the lower leaf surface, leaving the upper epidermis intact thereby creating a “window-paning” effect. Severe feeding damage will stunt cabbage and cauliflower heads. Skeletonizing resembles chewing of plant leaves between ribs and veins, and sometimes holes in forming cabbage heads.
[#273] I P M relies heavily on
Correct Answer
(A) Economic threshold level
Explanation
Solution: I P M relies heavily on Economic threshold level. Integrated pest management (is a way to control insects without relying solely on pesticides. It uses long-term prevention of pests or their damage through a combination of techniques such as biological control, habitat manipulation, change of cultural practices, and uses resistant plant varieties. Economic Threshold Level (ETL) is the index for making pest management decisions. It is defined as the pest population density at which control measures should be initiated against an increasing pest population to prevent economic damage.
[#274] Extremely toxic class of pesticides have colour of lower triangle
Correct Answer
(A) Bright red
Explanation
Solution: Extremely toxic class of pesticides have the Bright red colour of lower triangle. Toxicity labels like red label, yellow label, blue label and green label are mandatory labels employed on pesticide containers in India identifying the level of toxicity (that is, the toxicity class) of the contained pesticide. The schemes follow the Insecticides Act of 1968 and the Insecticides Rules of 1971 and contain information such as brand name, name of manufacturer, name of the antidote in case of accidental consumption etc. Red label is extremely toxic having maximum percentage of lethal dose.
[#275] The scientific name of paddy leaf hopper is
Correct Answer
(D) Nephoettix sp.
Explanation
Solution: The scientific name of paddy leaf hopper is Nephoettix sp. Nephotettix is a genus of planthoppers in the subfamily Deltocephalinae and tribe Chiasmini. Species are mostly found in Asia, although two are from Africa. It is known as 'green leafhoppers' of paddy/rice, Nephotettix cincticeps and N. virescens appear to be the most important Asian pest species in this genus: as vectors of viruses, such as tungro disease in rice.