AMHERST, Mass. (AP) _ Harold H. Plough, professor emeritus of biology at Amherst College, has died at the age of 93.

Plough, who specialized in the study of genetics, died Tuesday at his home here. He had taught at Amherst for 42 years prior to his retirement in 1959.

From 1951 to 1953 he served on the Atomic Energy Commission as assistant chief of the biology branch and was in charge of genetic investigations at atomic bomb tests in Nevada in 1953. He later lectured in Japan on the effects of radiation.

A trustee of the Woods Hole Marine Biological Laboratory, he continued his research on sea life into his 80s and published a book ''Sea Squirts of the Atlantic Continental Shelf'' in 1976.

Plough was born in New York City, graduated from Amherst College in 1913 and received his doctoral degree from Columbia University in 1917.

He is survived by his wife, Frances, and two sons.

A funeral was scheduled for Friday in Amherst.