Soil Science - Study Mode

[#651] The pF value of available water is
Correct Answer

(B) 2.54

Explanation

Solution: pF value characterizes the energy with which the soil water is held against gravity in the soil matrix. It is defined as the decadic logarithm of the amount of soil water tension in hectopascals. The higher the pF value, the drier the soil or the lower its water content. The pF value of available water is 2.54.

[#652] Mehlich's cunninghamella plague method is used to test . . . . . . . .
Correct Answer

(B) Phosphorus

Explanation

Solution: Mehlich’s cunninghamella Plaque method is used to test Phosphorous . In this method, the soil is mixed with the nutrient solution, a paste is made, spread uniformly in the well of a specially constructed clay dish, inoculated on the surface in the center of the paste, and allowed to incubate for a few days.

[#653] Stem nodulating Rhizobium species is
Correct Answer

(C) Azo-rhizobium

Explanation

Solution: Stem nodulating Rhizobium species is Azo-rhizobium. It belongs to the genus of Gram-negative soil bacteria. Like root nodulating bacteria they fix nitrogen in symbiosis with plants in the genus sesbania. Stem nodules occur at the site of adventitious root primordia located on the stems via crack entry.

[#654] Among the Metamorphic rocks which one having banded or laminar appearance?
Correct Answer

(B) Gnesis

Explanation

Solution: Gnesis is a metamorphic rock which is having banded or laminar appearance. It has a distinct banding, which is apparent in hand specimens or on a microscopic scale. It is formed by high-temperature and high pressure metamorphic processes acting on formations composed of igneous or sedimentary rocks.

[#655] Fe deficiency is mostly seen in crops growing on
Correct Answer

(A) Calcareous or alkaline soils

Explanation

Solution: Fe deficiency is mostly seen in crops growing on Calcareous or alkaline soils . The high soil pH is the most common cause of the iron deficiency. The deficiency of Iron is a major nutritional disorder that causes a decrease in vegetative growth and marked yield and quality losses.