Screening And Identifying The Stomatal Related Mutants Of Rice(Oryza.sativa)

Rice is a main cereal crop and staple food for over half of the world population. Rice has also become a model system of monocotyledon plants for genomic studies because of its relative small genome, mature transformation technique, the published various databases and the completion of the genomic sequencing projects of both indica and japonica subspecies.Stomata and epidermal cells were both model systems for studying the cell differentiation and plant development. In Arabidopsis, the great achievements of stomatal and epidermal development have been made. However, there was less correlative advancement in rice.In this experiment, we created the rice planting and mutant screening system, and screened four rice T-DNA insertion mutants, a smooth skin type (245em), a stomatal clusters type (340), a dwarf-type (245dm) and a higher type (367). After the initial phenotypic identification,340 and 245dm were chose to analyze in cellular and molecular level.The primary phenotype of 245em was that the lobes of leaf epidermis (similar to Arabidopsis lobes) disappeared and the epidermal cells became smooth. And the number and morphology of silica papillae were changed.The central phenotype of 245dm was that the plant was obvious dwarfing with smaller leaves before the 5th leaves stage. After the stage, the mutant phenotype of 245dm could recover to a certain extent. However, the same mutant phenotype of 245dm in the next generation would appear again. And leaf epidermal cells were compressed and part of guard mother cells (GMCs) did not divide to form guard cells. The T-DNA insertion site of 245dm has been found by hiTAIL-PCR, and 6580 was the presumption mutant gene by semi-quantitative RT-PCR and bioinformatics analysis.In 340, the leaf stomata clustered and the position, shape and function of various flower organs distorted. The differentiation of flower organs has degenerated and these mutant flowers could form new plants directly. The T-DNA inserted fragment in 340 was detected by southern blotting and PCR analysis, and found that the inserted fragment was not from the border of T-area of the DS-GUS plasmid. The left arm of inserted fragment extended to the V area of plasmid and the T area fractured within the right arm.