Availability of phosphorus is maximum at pH:

Autumn sown crop of sugarcane requires fertilizer than that of winter sown?

A. Equal

B. More

C. Less

D. Half

Azolla is a:

A. Water fern

B. Water algae

C. Water bacteria

D. Water protozoa

Azotobacter spp fix nitrogen:

A. As symbiouts on sugarcane

B. As symbiouts on rice

C. As symbiouts on legume

D. In free soil

Bacteria responsible for nitrification are:

A. Nitrosomonas

B. Nitrobacter

C. Above both

D. VAM

Balanced fertilizer is used:

A. To increase production

B. To improve quality of seed

C. To maintain soil productivity

D. All of these