Preliminary Study On Physalis In Vitro Flowering And Polyploid Induction

Physalis alkekengi is a kind of wild plant with high edible,medicinal and ornamental value.It can enhance the edible and medicinal value of the polyploid of P.alkekengi,and it is also conducive to the breeding of new varieties,the conservation of germplasm resources and the rapid production of seedlings.It has a broad application prospect.In this study,using colchicine as the mutagen,the methods of tissue culture and seed soaking were optimized to induce the polyploid of P.alkekengi,and the system of in vitro regeneration of P.alkekengi was established.The main conclusions are as follows:1.The P.physalis regeneration system with aseptic seedling cotyledons as explants was optimized.The optimal ratio of hormones for P.physalis callus formation were 6-BA3.0 mg / L + IAA0.5 mg / L and 6-BA2.0 mg / L + NAA0.1 mg / L,with the recovery rate of 85.56% and 93.33% respectively;the optimal ratio of hormones for bud differentiation were 6-BA3.0 mg / L + IAA0.1 mg / L,with the differentiation rate of 43.33%.The best rooting medium were MS + NAA0.1mg/l,MS +IAA0.05mg/l and MS + IBA0.1mg/l.which the rooting rate can reach to 100%.2.The method of in vitro tissue culture for inducing P.alkekengi tetraploid were optimized,The callus was induced from the cotyledon of aseptic seedlings.The chromosome doubling effect was the best with the doubling rate of 60.67% when the callus was treated with 0.2% colchicine for 15 days.3.The method of colchicine soaking were optimized.The germinated seeds at the dew-white stage were soaked in 0.15% colchicine for 1day,then washed with sterilized water and placed on the filter paper.When the roots were about 0.2 cm long,they were transferred to MS basic medium for further culture.The double effect was the best,and the double rate can be 29.76%.4.The culture medium and method of the in vitro flowering of P.alkekengi were optimized.Compared with 1 / 2 MS medium,MS medium is more suitable for P.alkekengi in vitro flowering,and sucrose is better than glucose and white granulated sugar The best concentration of 6-BA and NAA was 0.05mg/l and 0.15mg/l,respectively,and the flowering rate was 35.56% and 23.33%.The best photoperiod of inducing the flowering was light / dark: 12 h / 12 h,which the flowering rate can reach to 53.33%.