Agriculture Microbiology MCQ tribhuvan University 3

21. Widely used inexpensive technique to measure nitrogen fixation depends on
a. capability of nitrogen fixing enzyme (nitrogenase) to act upon acetylene.
b. Ninhydrin test
c. comparison of growth of plants in nitrogen supplemented and non supplemented fields.
d. direct measurement of fixed nitrogen from the soil
22. bacteria of the both physiological groups, ammonia oxidizers and nitrite oxidizers are
a. Gram Negative Chemolithotrophs b. both gram positive and gram negative Chemolithotrophs c. Gram Negative Chemoorganotrophs d. both gram negative and gram positive Chemoorganotrophs.
23. Degradation of Lignin in forest soil constitutes the example of
a. Neutralism b. Mutalism c. commensalisms d. competition
24. Ratio of the Microorganisms in the rhizoshphere compared to the microorganisms in the bulk soil i. e R:S ration typically ranges from
a. 2-5 b. 5-10 c. 10-50 d.4-8
25. Agricultural crops commonly contain ……………percentage of phosphorus in their tissue.
A. 0.05-0.5% B. 2.5-4% C. 2-3% D. 1-1.5%
26. Fungal mycelium and Bacterial biomass contain…………….. percentage of Phosphorus respectively.
a. 0.5-1% and 1-3% B.0.05-0.5% and 0.5-1% C. 2% and 3% D. 2.5-4% and 1.5-2.5%
27. ………….. is called as Father of Soil Microbiology.
A. Hiltner B Ruinen C Winogradsky D. Beijernickia
28. Nitrogen (N2) becomes a nitrate through the process of
A. Nitrification B. Nitrogen fixation C. Ammonification D. Denitrification
29. Chemoautotrophy is discovered by,
A. Hiltner B Ruinen C Winogradsky D. Beijernickia
30. Nitrogen Fixing stage of rhizobium is called
a. Rhizoid b. Bacteroid c. Viroid d. Bacteria