Fertility of the soil in rice fields can be improved by

Identify the correct statements regarding mycorrhiza:
$(1)$ Many members of the genus $Glomus$ form mycorrhiza.
$(2)$ It is responsible for all mineral absorption from the soil.
$(3)$ Such associations show benefits against drought and salinity in plants.
$(4)$ Mycorrhiza is a symbiotic association between fungi and roots of higher plants.

Farmers have reported over $50\%$ higher yields of rice by using which of the following biofertilizer?

The aquatic fern which is an excellent biofertilizer is ......

Which one of the following is not a biofertiliser?

Azolla is used as a biofertiliser because it