Plant Regeneration And In Vitro Culture From Peach Rootstock(Prunus Persica)

An efficient and stable regeneration system is a pre-requisite for plant genetic transformation. Peach is difficult to regenerate from in vitro-cultured explants, which has largely hindered the development of new varieties using the tools of modern biotechnology. In this study, the peach rootstock (Prunus persica) widely cultivated in Southern China was used as experiment material. Using the leaves of aseptic plantlets derived from stem segment as explants and plant tissue culture method, effects of different basic medium, plant growth regulator types and content, carbon source and dark period on adventitious shoot regeneration and callus induction, conversation and regeneration were investigated. This study preliminarily established an in vitro regeneration system from ’mao tao’, which laid the foundation for further genetic transformation attempts. The main results were as follows:1. In May to June2010, the induction of axillary buds was performed via in vitro shoot segment culture. The germination percentage was up to76.6%and the buds had a strong growth potential. The most appropriate medium for proliferation of’mao tao’was LP medium supplemented with0.75mg/L6-BA,0.3mg/L IBA,3.0mg/L Ad,30.0g/L sucrose and agar6.8g/L. The plants were subcultured every30d.2. The leaves explants of ’mao tao’ were excised from the plantlet, placed horizontally on the medium and cultured at25±2℃in the dark. After21d, the cultures were transferred to fresh medium and cultured under16h photoperiod. The optimal medium for both darkness and light treatment was SH medium supplemented with3.0mg/L TDZ,0.3mg/L NAA,30.0g/L sucrose and6.0g/L agar, on which the maximal regeneration rate reach11.67%.3. The optimal medium for rooting of ’mao tao’ in vitro consisted of1/2LP medium with1.0mg/L IBA,0.1mg/L NAA,20.0g/L sucrose and6.8g/L agar, pH5.8-6.0. The highest rooting percentage was up to73.34%. On average,3roots each approximately4.81cm in length were generated from each test-tube plantlet.4. The optimal medium for callus induction from ’mao tao’ was LP medium containing1.0mg/L6-BA,3.0mg/L2,4-D,0.5mg/L AgNO3,30.0g/L sucrose and6.0 g/L agar, pH5.8-6.0. The young stem (without axillary) and leaves with petioles explants were excised from30d in vitro culture shoots, placed horizontally on the medium, maintained in the dark for21d at25±2℃and then transferred to16h photoperiod.5. The optimal medium for callus conservation of ’mao tao’ was LP medium supplemented with1.5mg/L2,4-D,0.4g/L CH,3.0g/L CA or3.0g/L PVP,30.0g/L sucrose and5.8g/L agar, pH5.8-6.0. The calli were maintained in the dark at25±2℃and transferred to fresh medium every28d.