| Increasing yield level per unit area is forever theme for rice breeding aim, and advancing photosynthesis efficiency is one of key factors for improving grain yield. The leave premature senescence will reduce chlorophyll content and shorten photosynthetic time, which further influence yield. In this study, PPF1 gene, which could delay leave senescence as donor, callus derived from indica rice cultivar shuhui881, shuhui527, 501R and japonica rice cultivar zhonghua9 as acceptor were transformed by Agrobacterium-mediated transformation and particle bombardment of Biolistic PDS-1000/He Delivery System(Bio-RAD). After selection, pre-regeneration, regeneration and rooting, 18 resistant plant lines were obtained in total by Agrobacterium-mediated transformation. In order to identify the integration and expression of the foreign gene, PCR, Dot blot and Southern blot were used, furthermore genetic analysis and molecular detection of shuhui881 TI progeny were carried out, the results showed that the PPF1 gene was integrated to transgenic rice plants. The main results as follow:1. The difference effect of rice callus induction and differentiation on different culture medium was researched. The results indicated that the highest efficiency of callus induction was obtained with NB medium and the best differentiation with MS.2. The differences were found in induction, subculture, physiological status and differentiation in different explants. In a word, only mature embryo induction was higher than immature embryo, in the other aspects immature embryo was better than mature embryo. So immature embryo was an ideal explants.3. In agrobacterium-mediated transformation, callus physiological status effected on the resistant callus frequency, callus subcultured one time grew better than both unsubcultured and subcultured for three times, and the percent of resistant callus subcultured for once was 38.96%, the others were 23.86% and 26.66% respectively. The efficiency of resistant-acquired callus was affected by agrobacterium in different kinds of medium. For example, it was the best efficiency for ZH9 to use 2/3NB+1/3YEB medium, 50.76% of resistant callus was acquired in this medium. Four varieties were all successfully transformed by Agrobacterium-mediated transformation and 18 resistant plant lines were gained, of which 5,3,2,and 8 plant lines were gained in shuhui527,shuhui881, 501R and zhonhhua9 respectively.4. It was proved that the PPFl gene has been integrated to the TO transgenic lines by DNA analysis. The PCR analysis of all TO regeneration plants indicated that 17 PCR positive plant lines were obtained by PCR marker (hpt) and 14 positive plant lines were obtained by PCR marker for the foreign target gene (PPF1) .The same result was showed by Dot blot and Southern blot analysis of 14 PPFl-PCR positive plant lines . Such further confirmed the PPFl gene had been integrated into the genome of transgenic rice plants.5. The chlorophyll content, senescence index and the leaf color were surveyed. The results showed that the chlorophyll content and the senescence index of SH881 which contained PPFl, shortened as SH881-PPF1, was higher than SH881. While the SH881-PPF1's leaf color was darker than the control plant. It showed that the PPF1 was expressed in transgenic lines.6. The T1 progenies of transgenic lines were analyzed. The results showed that Most of the TO self-crossing seed could grow normally and show hygromicine resistance ,The T1 progenies of transgenic lines were segregated in accordance with Mendel's single gene inheritance rule; PCR analysis for the resistance progenies of transgenic lines has been done .The result showed that resistance progenies were positive for all hpt marker for most of PPFl marker .Three T1 progenies of hygromicine resistance SH881 were randomly selected to further tested by Dot blot. The result showed that the foreign gene has been stably inherited to T1 progenies.
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