The dormancy of bulbs, roots and tubers can be prolonged by________?

A type of resistance in which a series of different cultivars of the same crop are infested with a series of different insect biotypes of same species show a differentia interaction is known as________?

Nitrification is the microbial conversion of________?

Heat, cold and frost resistance ideotype have been developed in________?

Gassypium arborium is________?

The reason why mutations which are harmful do not eliminated from gene pool is that________?