Abstract
Morphological and histochemical comparisons of pollen were made among the following rice strains (a) Fujisaka No. 5, an improved Japanese variety; (b) a strain of Chinese wild rice, O. sativa f. spontanea ; (c) a male-sterile, Fujisaka No. 5-type strain with spontanea cytoplasm ; (d) a normal spontaneatype strain with Fujisaka No. 5 cytoplasm. The last two of these were made by Katsuo and Mizushima (1958) through nuclear substitution. In microcytes at the tetrad stage polysaccharide content was observed to be less in (c) than in (d), (a), and (b). Localization of starch grains to the polar site of germpore of pollen was recognized in (d), (a), and (b), but not in (c). Translocation of starch grains to the site was confirmed to take place at the time of anther dehiscence in the former three. The pollen of (d), (a), and (b) germinated on artificial culture media, whereas those of (c) did not and puffed out cytoplasm. Majority of the pollen of (d), (a), and (b) puffed out cytoplasm soon after being soaked in distilled water. Occurrence of this plasmoptyse was not so remarkable in the case of (c) . Pollen of all the strains showed similar amylase activity as well as equal maltose and glucose content.
