Abstract
We investigated the cytological characteristics and inheritance of the male sterility in Shindai 8, recently found in Niigata Prefecture, Japan. The process of microsporogenesis was normal. However, pollen mitotic defects were observed in the microspore and a defective pollen wall was produced. The nucleus of the microspore faded and finally the microspores agglomerated. Backcrossed seedlings obtained from Shindai 8 segregated into 50% fertile and 50% sterile seedlings. Moreover, seedlings obtained from crossings of Shindai 8 with other male sterile lines (Toyama MS, Shindai 1 , Shindai 3, Shindai 5, and Shindai 7) had only fertile male flowers. The male sterility trait in Shindai 8 is nuclear sterility controlled by a pair of recessive genes, and the male sterility in Shindai 8 is controlled by different genes than in other male-sterile C. japonica.
