Indian Agricultural Research Institute

As per the ICAR AIEEA PG 2020 prospectus, there is no course available for B.Sc. Botany. Hence you can not apply.

M.Sc. Chemistry or M.Sc. (Hons) Chemistry but sorry to say you cannot proceed for PG Course as the eligibility for PG Agri is you should have done B.Sc. In Agriculture (4 years)
I will advice yo to identify a right institute like LPU because of its exposure provided ti students and the types of placements arranged by the University. Stick to Chemistry only and pursue your M. /Sc as this programme prepares a student to become an effective teacher, chemist and a good researcher
You need to track the dates of admission and eligibility norms of the god institute as I know one institute I. e.