Poster: Late & Moved Abstracts

Abs # 1014: Study of inducible genic male-sterility in rice: Complete pollen abortion induced by thermo-variation.

Presenter:	Chung, Yong-Yoon , ychung@korea.ac.kr
Authors	Chung, Yong-Yoon  (A)   Lee, Sang Hee  (A)   Kang, Mira  (A)   Kim, Shinje  (B)   Suh, Hak Soo  (C)
Affiliations:	(A): Dept. of Biology, Korea University (B): Center for Plant Molecular Genetics and Breeding Research, Seoul National University (C): School of Biological Resources, College of Natural Resources, Yeungnam University
Web Site:	http://biology.korea.ac.kr/~pmdblab

We have studied thermo-sensitive genic male-sterility (TGMS) in rice. Several TGMS rice lines were tested for fertility at different thermo-conditions. Two of them were found that they undergo complete pollen abortion during the anther development at 32”ĘC while they produce normal pollen grains at 26”ĘC. Others also showed the pollen abortion phenotype, but they are partially affected by photoperiod and produce pollen grains at different daylength condition. This suggest that the male-sterility of those lines are possibly controlled by more than one gene. In order to find structural differences between the anthers developed at the two different thermo-condition, sterile and fertile condition, the anthers were dissected and examined under a light microscope and also a transmission electron microscope. The male sterile rice anther contained completely empty locules without pollen grains whereas other tissues of the anther were developed normally. At pollen-mother cell stage, however, the male sterile rice anther did not show any structural difference from wild-type and/or male-fertile rice anther, suggesting that the pollen abortion occurred after the pollen meiosis. Molecular identification of the gene responsible for the inducible male-sterility is discussed.