Cyto-histological Studies on Callus Formation and Its Regeneration in Anther Culture of Oryza satiz}a L.

[摘要] Histological characteristics of globular shaped pollen callus (globules) developed from multicellular pollen grains were examined in rice anther culture (Oryza sativa L.). The ultrastructure of pollen grains, anther wall tissues and the globules in vitro were also claritied. It was speculated that the microbodies observed in the viable pollen grains and anther wall tissues were associated with the lipid metabolism during the formation of the multicellular pollen grains. Before de-differentiating cells emerged from the pollen wall (exine), mucilage was secreted on the outer-surface of the exine. The presence of multivesicular bodies in the multicellular pollen grains was analyzed in relation to their function in mucilage secretion. Lipid droplets and starch grains were formed in the globules after the emergence. Thereafter, a shoot-root axis appeared in the globules in the anther culture medium. When the meristem of the future root apex appeared at the root pole of the globules, the starch grains and lipid droplets decreased in the meristem. These results suggest that the formation of the globules in the anther culture and plant regeneration in vitro were accompanied with dynamic changes in the carbohydrate and lipid metabolism.

[学科分类] 农业科学（综合）

[关键词] Anther culture;イネ;Callus;カルス;Oryza sativa;植物体再分化;Plant regeneration;微細構造;Rice;葯培養;Ultrastructure