An element playing important role in nitrogen fixation is
Which one of the following is not a micronutrient?
The free-living, anaerobic nitrogen-fixer is
The common nitrogen-fixer in paddy fields is
Which of the folowing is a symbiotic nitrogen fixer?
About 98 percent of the mass of every living organism is composed of just six elements including carbon, hydrogen, nitrogen, oxygen and:
(a) phosphorus and sulphur
(b) sulphur and magnesium
(c) magnesium and sodium
(d) calcium and phosphorus
Which one of the following elements is not an essential micronutrient for plant growth?
A plant requires magnesium for
(a) holding cells together
(b) protein synthesis
(c) chlorophyll synthesis
(d) cell wall development
Farmers in a particular region were concerned that pre-mature yellowing of leaves of a pulse crop might cause decrease in the yield. Which treatment could be most beneficial to obtain maximum seed yield?
(a) Frequent irrigation of the crop
(b) Treatment of the palnts with cytokinins alongwith a small dose of nitrogenous fertilizer
(c) Removal of all yellow leaves and spraying the remaining green leaves with 2, 4, 5 trichlorophenoxy acetic acid
(d) Application of iron and magnesium to promote synthesis of chlorophyll
Sulphur is an important nutrient for optimum growth and productivity in:
(a) pulse crops
(c) fibre crops
(d) oilseed crops