Dept. of Plant Sciences, University of California, Riverside, Cal., U.S.A.
*Present address: Cetus Madison Corporation., 2208 Parview Road, Middleton, Wsconsin, 53562, U S.A.
Three genetically diverse single-plants elections exhibited male-sterility and poor female-fertility at the fields in Riverside. California, but had good male and female-fertility in the greenhouse. The male-sterility in the field was due to shortened filaments of the anthers so that anthers did not reach the stigma, lack of viable pollen and the failure of the anthers to dehisee at maturity. The male sterility, in each case, was determined by a single recessive gene pair, the expression of which was controlled by the cold night temperatures in the field.
