Establishment Of Rice Suspension Cell Line And Study On Programmed Cell Death Induced By Heat Shock And Chloroplast Fractions

Programmed Cell Death (PCD), a physiological cell death process, is associated with the differentiation of vessel and sieve tube, the propagation, senescence, the hypersensitive reaction of plants, and so on. PCD can be induced by modest abiotic stress treatments. PCD in plants, with little ratio and short process, is not advantageous to detection and further researches, whereas, culture in vitro possesses high synchronization and quantity of induction. Rice is one of the most important crops, whose study on PCD deserves a lot of further researches. Based on establishment of suspending cell line and regeneration systems of rice (Oryza sativa L.) 'Zhonghua 11', we established PCD system of suspending cells by heat shock. PCD of the suspension cells, which could be induced by chloroplast was tentatively confirmed.Using seeds of rice 'Zhonghua 11' as explant, from which callus was induced on MS medium with different concentrations of 2,4-D and the suspension cell line was established in the AA medium. The combination of nitrogen, inosite and 2,4-D concentrations was set up to study their effects on the biomass production of rice 'Zhonghua 11' suspension cell in AA medium. The results showed that the highest biomass was obtained on the optimized medium with 5 mg·L^-1 2,4-D, 100 mg·L^-1 inosite and 150% AAN. After culture of the suspension cells on MS medium with 3 mg·L^-1 2,4-D and the callus on regeneration medium subsequently, we found that the optimum regeneration medium is MS basic medium with 0.2 mg·L^-1 NAA, 1.5 mg·L^-1 CuSO₄·5H₂O, 2 mg·L^-1 6-BA and 16 g·L^-1 agar.