Plant Pathology - Study Mode

[#126] Hydroponics is
Correct Answer

(D) Soil-less cultivation of plants

Explanation

Solution: Hydroponics is Soil-less cultivation of the plant. Hydroponics is a type of horticulture and a subset of hydroculture that involves growing plants, usually crops or medicinal plants, without soil, by using water-based mineral nutrient solutions in aqueous solvents. The nutrients used in hydroponic systems are different organic or inorganic sources, including fish excrement, duck manure, purchased chemical fertilizers, or artificial nutrient solutions.

[#127] The change of NH + 4 to NO - 3 is called as
Correct Answer

(A) Nitrification

Explanation

Solution: The change of NH + 4 to NO - 3 is called Nitrification. Nitrification is the biological oxidation of ammonia to nitrite followed by the oxidation of the nitrite to nitrate occurring through separate organisms or direct ammonia oxidation to nitrate in comammox bacteria. The transformation of ammonia to nitrite is usually the rate-limiting step of nitrification. Nitrification is an important step in the nitrogen cycle in soil. Nitrification is an aerobic process performed by small groups of autotrophic bacteria and archaea.

[#128] Which pair is wrong?
Correct Answer

(A) C 3 - Maize

Explanation

Solution: A. C 3 plants include some of the most important sources of calories all over the world: cowpea, cassava, soybean and rice. Grasses, such as maize, sorghum and sugarcane, are widely cultivated in modern agriculture are C 4 plants. B. Calvin cycle ⟶ PGA. Phosphoglyceric acid, PGA is the conjugate acid of 3-phosphoglycerate or glycerate 3-phosphate. This glycerate is a biochemically significant metabolic intermediate in both glycolysis and the Calvin-Benson cycle. C. Hatch and Slack cycle ⟶ OAA. The Hatch and Slack pathways are also known as the C 4 pathway because the first stable product of this pathway is 4-C carbon compound OAA (Oxaloacetate ). D. C 4 - Kranz anatomy. The C 4 biochemical pathway relies on a specific suite of leaf functional properties, often referred to as Kranz anatomy.

[#129] For the effective control of wilt, pigeonpea should be intercropped with
Correct Answer

(C) Sorghum

Explanation

Solution: For the effective control of wilt, Pigeon pea should be intercropped with Sorghum. Fusarium wilt of pigeon pea is both a soil-borne and seed-borne disease in which the infection level of untreated seeds may range from 13% to 19%. The infected seeds thus serve as a primary vehicle for the spread of this disease over long distances or to newer areas. Sorghum as an intercrop has been found to reduce wilt (Fusarium udum) incidence in pigeon pea by about 30 percent.

[#130] The maximum fixation of K occurs
Correct Answer

(D) In 2 : 1 type clay minerals

Explanation

Solution: The maximum fixation of K occurs in 2 : 1 type clay minerals. The major minerals responsible for K fixation are illite, vermiculite and smectite. It has been demonstrated that vermiculite and smectite minerals have more ability to fix K compared to other 2 : 1 minerals due to the higher specific surface area and negative layered charge.