Soil Science - Study Mode
[#861] Which of the following is nitrogenous fertiliser for amide group?
Correct Answer
(B) Urea
Explanation
Solution: Among the given options, Urea is the nitrogenous fertilizer for the amide group. It contains nitrogen in amide form but this form of nitrogen is swiftly converted by soil microorganisms into ammonical form and then into nitrate form. Urea is a white crystalline solid containing 46% of nitrogen as an animal feed additive and fertilizer.
[#862] Ethanol soluble fraction of Humic acid is
Correct Answer
(D) Hymatomelanic acid
Explanation
Solution: Humic acids are the organic substances that coagulate when the strong base extract is acidified. Humic acids are organic molecules with complex structures and functions and variable properties. Fractionation of humus sample is done to determine its solubility and the fractionated materials are likely to be heterogeneous and a large amount of sample would be necessary for their analysis. The ethanol soluble fraction of Humic acid is Hymatomelanic acid .
[#863] Microbial Biomass generally constitute . . . . . . . . % of total soil mass.
Correct Answer
(B) 0.01 - 0.4%
Explanation
Solution: Soil microbial biomass is a measure of the mass of the living component of soil organic matter. The microbial biomass decomposes plant and animal residues and soil organic matter to release carbon dioxide and plant available nutrients. The microbial biomass of the soil was determined by killing and lysing the soil microbes by fumigation with chloroform, irradiation with gamma rays or irradiation with microwaves. Microbial biomass generally constitutes 0.01 - 0.4% of total soil mass.
[#864] Central soil salinity research institute is located at
Correct Answer
(B) Karnal
Explanation
Solution: Central soil salinity research institute is located at Karnal . It is a premier research institute dedicated to pursuing interdisciplinary research on salinity or alkalinity management and the use of poor-quality irrigation waters in different agro-ecological zones of the country. It works for the reclamation of rain-fed salt-affected soils, bio saline agro-forestry for fuel wood, bio-fuel, and energy plantation.
[#865] Hartig nets in soil produce by
Correct Answer
(B) Ectomycorrhiza
Explanation
Solution: A Hartig net is a complex of fungal hyphae found in the intercellular spaces between the cortical cells of a root. It may cover the plant cell to the extent that the cell has no contact with other root cells. Hartig net in the soil is produced by ectomycorrhiza. Ectomycorrihizas is a form of symbiotic relationship that occurs between a fungal symbiont and the roots of various species. The hyphae in the Hartig net penetrate and grow in a transverse direction to the axis of the root, and form a network between the outer cells of the root axis.