What is required for nitrogen fixation by Rhizobium
Potassium
Phosphorus
Nitrate
Sodium
The chemical present in Temik is
A natural insecticide obtained from plants is
As insecticides reach at higher trophic level in food chain their concentration
The first fungicide discovered for plant disease control was
Which one among the following is likely to have the highest levels of $DDT$ depositions in its body