Plant Pathology - Study Mode

[#356] The C : N ratio of saw dust is
Correct Answer

(B) 225 : 1

Explanation

Solution: The C : N ratio of sawdust is 225 : 1. Organic matter that is deposited in marine sediments contains a key indicator as to its source and the processes it underwent before reaching the floor as well as after deposition, its carbon to nitrogen 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. It is other things that, be used in analyzing sediments and soil including soil organic matter and soil amendments such as compost.

[#357] The nutrient with a key role in biological N-fixation is
Correct Answer

(D) Mo

Explanation

Solution: The nutrient with a key role in biological N-fixation is Molybdenum. Nitrogen fixation is a chemical process by which molecular nitrogen (N 2 ), with a strong triple covalent bond, in the air is converted into ammonia (NH 3 ) or related nitrogenous compounds. The conversion of N 2 into ammonia occurs at a metal cluster called FeMoco, an abbreviation for the iron-molybdenum cofactor. Molybdenum-dependent nitrogenase is the most commonly present nitrogenase.

[#358] Which of the following elements is not major nutrient element?
Correct Answer

(D) Zn

Explanation

Solution: Zn element is not the major nutrient element. Zinc is a micronutrient for plants, require in less quantity for growth and development. Zinc participates in chlorophyll formation, and also activates many enzymes. Symptoms of zinc deficiency include chlorosis and stunted growth.

[#359] Which photosynthetic bacteria possess both PS I and PS II?
Correct Answer

(B) Cyanobacteria

Explanation

Solution: Cyanobacteria photosynthetic bacteria possess both PS I and PS II. Cyanobacteria are photosynthetic microorganisms that are abundant in nature. There are two types of photosystems in cyanobacteria, algae, and higher plants, called photosystem I (PSI, plastocyanin-ferredoxin oxidoreductase) and photosystem II (PSII, water-plastoquinone oxidoreductase), both of which are multisubunit membrane complexes.

[#360] The most striking symptom of false smut of rice (Claviceps oryzae-sativae) is/are
Correct Answer

(D) All of these

Explanation

Solution: The most striking symptom of false smut of rice (Claviceps oryzae-sativae) is the Transformation of individual kernels into large, velvety, green balls, Sometimes the size of the kernel is more than twice the diameter of the normal grain, and also the colour of the kernels finally changes to greenish black. False smut causes chalkiness of grains which leads to a reduction in grain weight. It also reduces seed germination. Plants infected with false smut have individual rice grains transformed into a mass of spore balls. These spore balls are initially orange and then turn greenish black when these mature.