$A$ : Barley, Sorghum and millet are smoother crops.
$R$ : They favour the growth of some common weeds.
Assertion and Reason both are correct and also correct explanation.
Assertion and Reason both are correct but not explanation of assertion.
Assertion is correct, but Reason is incorrect.
Both Assertion and Reason are incorrect.
Which one of the following proved effective for biological control of nematodal diseases in plants ?
They are proteinous infectious agents.
Nitrogen fixation in root nodules of Alnus is brought about by
Concept of sustainable agriculture lies in