He worked on embryological aspects and popularised the use of embryological chracters in taxonomy. He established the Department of Botany, University of Delhi as an important centre of research in embryology and tissue culture. He also emphasised the need for initiation of work on artificial culture of immature embryos. These days, tissue culture has become a landmark in science. His work on test tube fertilisation and intra-ovarian pollination won worldwide acclaim. He was honoured with fellowship of Royal Society of London, Indian National Science Academy.