Plant Pathology - Study Mode

[#211] Which of the following organic manures has the narrowest C/N ratio?
Correct Answer

(C) Groundnut cake

Explanation

Solution: Groundnut cake from the following organic manures has the narrowest C/N ratio.
A carbon-to-nitrogen ratio (C/N ratio or C : N ratio) is the ratio of the mass of carbon to the mass of nitrogen in organic residues. Groundnut cakes are suitable for all types of crops. Nutrient content percentage % ratio for this manure is, N : P : K = 7.3 : 3 : 2.2. This helps in improving the health of plants and thus enhances the crop yield. It is often used to boost the growth of fruit, flower and vegetable crops.

[#212] The effective concentration of HC toxin in μg/ml is
Correct Answer

(B) 0.2

Explanation

Solution: The effective concentration of HC toxin in μg/ml is 0.2. HC-toxin is a cyclic tetrapeptide of the structure cyclo (D-Pro-L-Ala-D-Ala-L-Aeo), where Aeo stands for 2-amino-9,10-epoxi-8-oxodecanoic acid. It is a determinant of specificity and virulence in the interaction between the producing fungus, Cochliobolus carbonum, and its host, maize.

[#213] Calcium, magnesium and sulphur are defined as
Correct Answer

(C) Secondary nutrients

Explanation

Solution: Calcium, magnesium and sulphur are defined as Secondary nutrients. Secondary nutrients are those that plants require in smaller quantities. Calcium regulates the transport of other nutrients into the plant and is also involved in the activation of certain plant enzymes. The outstanding role of magnesium in plant nutrition is as a constituent of the chlorophyll molecule. Sulphur is a structural component of some amino acids and vitamins, and is essential for chloroplast growth and function.

[#214] The spores which are produced typically by the binucleate mycelium and mainly function as repeating spores for the spread of rust disease in wheat is called
Correct Answer

(C) Urediospores

Explanation

Solution: The spores which are produced typically by the binucleate mycelium and mainly function as repeating spores for the spread of rust disease in wheat are called Uredospores. Urediniospores (or uredospores) are thin-walled spores produced by the uredium, a stage in the life cycle of rusts. Urediniospores usually have two dikaryotic nuclei within one cell. In mass, they are usually pale brown in contrast to teliospores which are generally dark brown.

[#215] The process of photophosphorylation was discovered by
Correct Answer

(B) Arnon

Explanation

Solution: The process of photophosphorylation was discovered by Arnon. Cyclic photophosphorylation occurs in both aerobic and anaerobic conditions, driven by the main primary source of energy available to living organisms, which is sunlight. In photophosphorylation, light energy is used to pump protons across a biological membrane, mediated by the flow of electrons through an electron transport chain. This stores energy in a proton gradient.