Vol. 20 >B. Research Notes>III. Genetics of morphological traits |
10. | Morphological classification of twelve rice mutants that cease embryogenesis at early globular stages |
E. TAKABE1,*, N. SENTOKU2, Y. NAGATO3,
M. MATSUOKA4 and H. KITANO4 1) Graduate School of Bioagricultural Science, Nagoya University, Nagoya, 464-8601, Japan 2) National Institute of Agrobiological Sciences, Tsukuba, 305-8602, Japan 3) Graduate School of Agricultural and Life Science, University of Tokyo, 113-8657, Japan 4) BioScience and Biotechnology Center, Nagoya University, Nagoya, 464-8601, Japan *) Present address: National Institute for Basic Biology/ Center for Integrated Bioscience, Okazaki National Institutes, Okazaki, 444-8585, Japan |
Many genes are involved in embryogenesis in plants. We have isolated
12 recessive mutants, derived from four independent loci; gle1
at GLE1 (GROBULAR EMBRYO 1), two alleles (gle2-1,
gle2-2) at GLE2, gle3 at GLE3 and two alleles
(gle4-1, gle4-2) at GLE4 (Hong et al. 1995),
and seven mutants of Organ Differentiation Mutant (odm) category, that
cease embryogenesis at early globular stages, from M2 population of cv.
Taicung65 mutagenized with MNU. In this report, we classified these mutants
into three classes from histological analysis.
embryo of wild type until the globular stage, and the outermost
layer of embryos of these mutants seem to differentiated into epithelium.
Differentiation of epithelium was confirmed on one of type2 mutants, gle4-1
by in situ hybridization analysis with probe for Ramy1A
gene that has been used as a marker of epithelium (Sugimoto et al.
1997). This category includes gle4-1 and gle4-2. In
Type3, the size of mutant embryo at full-mature stage is clearly smaller
than other types. The activity of cell division in the embryogenesis of
Type3 mutants was low and a number of cells of mutant embryo were very
few. The features that senescence begins from early developmental stage
and the cells arrangement in the outer layer of matured embryo is irregular
also characterized Type3 mutants. This category included odm63, odm78,
odm142 and odm157. |
Vol. 20 >B. Research Notes>III. Genetics of morphological traits |