%A GUO Jing-Yu, CHEN Zhi-Xiong, YANG Bing-Yao, CHEN Xin-Fen, LIU Xiang-Dong, LEI Yong-Gen %T Differentiation of Multiple Shoot Apical Meristems in Mutant Rice with One Embryo Causing Multiple Plumuples %0 Journal Article %D 2011 %J Acta Agronomica Sinica %R 10.3724/SP.J.1006.2011.02251 %P 2251-2260 %V 37 %N 12 %U {https://zwxb.chinacrops.org/CN/abstract/article_4965.shtml} %8 2011-12-12 %X The proper formation and development of shoot apical meristem during plant embryonic development is prerequisite to generate leaves, buds and stems. Rice (Oryza sativa L.) mutant line 4001 produces multiple plumules in one seed and is considered as an important mutant with abnormal differentiation of shoot apical meristem. While the embryonic basis of the mutant with multiple plumules is yet unknown. To elucidate the cytological basis, mature embryo sac structure and process of double fertilization were observed with whole-mount eosin B-staining confocal laser scanning microscopy (WE-CLSM), semi-thin plastic sections and scanning electron microscopy (SEM). The observation by WE-CLSM showed that both embryo sac structure and double fertilization process were normal in the mutant line, suggesting that the abnormal traits were related to the later embryonic development. By semi-thin plastic sections and SEM, the retardation of embryonic development and the formation of multiple shoot apical meristems (SAM) under abnormal orientation were observed in one embryo of the mutant line, compared with those of wild-type rice. At three days after pollination, the process of embryonic development was slower in the mutant line than in the wild type rice. The abnormality included the diverse number of SAMs under irregular orientation and the changes of dorsal-ventral axis. Two separate plumules, two plumules in one coleoptile and two connected plumules with one separate plumule were also observed in the mutant line 4001. It was concluded that differentiation of multiple SAMs and the the changes of dorsal-ventral axis in one embryo contribute to the multiple plumuples in the mutant line. It was inferred that mutant trait-related genes might play important roles in the regulations of the timing of shoot apical meristem differentiation, the number of undifferentiated cells and the establishment of dorsal-ventral axis.