Chestnut Tissue Culture And Browning

Castanea mollissima species shao shiba was the main research material in this experiment, other ten species were assistance research material. I researched the optimum medium of the different species and explant for inducing callus, subculture and regenerate on Castanea mollissima through tissue culture technique. The results showed that different species of Castanea mollissima need different medium, and WPM + 6-BA0.5+NAA0.2 was shao shiba's optimum inducing medium, and the inducement rate of embryo (79.5%) was higher than other explants. The subculture medium of shao shiba was WPM+6-BA0.5-1.0+NAA0.2.Because of containing much tannin, the explant of Castanea mollissima brown seriously, which interfered with normal propagation of Castanea mollissima tissue culture. Take shao shiba as research material, I studied the mechanism of explant browning of Castanea mollissima and factors influencing the explant browning in subculture. Then 1 find out the efficiency measures of alleviating browning.I researched the effect on browning of different concentration added materials , different concentration of AgNO3, light condition, temperature and pH. The result suggested that the conditions of 6g. L-1 PVP, 10mg.L-1 AgNO3, prophase dark treatment, 19℃ and pH 5.8 - 6.0 avail to lighten brownimg. Electrophoretic character of POD isozyme of the different species' different materials were studied, 1 found out the relation of different species and the differentiation degree of different materials.According to the browning phenomenon of Castanea mollissima in plant tissue culture and the activity of the peroxidase and polyphenolic oxidase, the results of my study indicated that the activity of PPO has relativity with the browning of the callus, that is the higher activity of enzyme,the more severity of browning.But POD was not as PPO.At the same time, analyzing correlation reveals that the correlation relationship of different harm degree and total phenol content is significant, 1 conclude that harm produce more phenolic, so total phenolic content deteriorate the degree of browning.