The plant ash is an indication of :
organic matter of plant
waste product
mineral salts absorbed by plants
none of these
The non- photosynthetic, non- symbiotic N2 fixing bacteria are
Rhodobacter
Spirillum
Azotobacter
All of these
Sulphur is an important nutrient for optimum growth and productivity in
pulse crops
cereals
fibre crops
fibre crops
Assertion: Nitrogen-fixing bacteria in legume root nodules survive in oxygen-depleted cells of nodules.
Reason: Legheamoglobin completely removes oxygen from the nodule cells.
If both Assertion and Reason are true and Reason is the correct explanation of Assertion
If both Assertion and Reason are true but Reason is not the correct explanation of Assertion
If Assertion is true but Reason is false
If both Assertion and Reason are false.
Hydroponics is
cultivation of plants in water
growth of plants towards water
growth of plants away from water
soil less cultivation of plants
Which of the following element plays an important role in nitrogen fixation
Zinc
Molybdenum
Manganese
Copper