Morphogenesis, Genetic Analysis And Molecular Tagging Of Genes For Fon(t) And Spp1 Mutants From Rice

Genetic and molecular mechanism underlying the regulation of floral development has become one of important subjects for plant development biology. The mutants of floral development were important for the studies on gene expression and function. In monocot plants, most of genes involved in floral development were isolated by screening the cDNA or DNA library with the probes homologous to sequences of dicot plants, and their functions were identified by the altered morphology of floral organs in transgenic plant. Understanding of the regulation on floral development was limited greatly, since some changed traits in transgenic plant were not consistent with the function of genes. Rice is not only the most important food crop in the world, but also a model plant for study of the molecular developmental biology in monocots. Studies on the rice reproductive organ mechanisms will be significant in theory and in practice.We obtained two rice flower organ mutants from the hybrid progeny of haploid X diploid and the breeding material respectively. In this study, we have completed the investigation of the morphogenesis progress in two flower organ mutants, genetic analysis of mutant traits and molecular mapping of related genes. Furethermore, the double mutants were construred to reveal the interactions of related genes. The main results are summarized as follows.â…  About the fon(t) (flower organ number) mutant1. The investigation of the flower morphogenesis: Compared with the wild type, the mature fon(t) flowers showed open-hull phenotypes. A single floret consisted six to nine stamens, one or two pistils. Stamen/pistil-like structures and bulged tissues near ovaries were also observed in some fon(t) florets. Homeotic transformation of lodicules into palea/lemma-like organs were observed in almost of all the open-hull florets.Flower organ development in earlier stages by SEM: The first difference between fon(t)...