Polyploid Induction of Physalis pubescens L.by Seed Soaking

Taking the germinated seeds of Physalis pubescens L.as materials.A seed soak experment was conducted to evaluate the effects of concentrations and treat time of colchicine on phenotypic variation and death rate of Physalis pubescens L.,in order to optimize the polyploidy induction system of Physalis pubescens L..The results showed that the hypocotyl enlargment rate increased followed the increase of concentration and treat time of colchicine, but decreased at long treatment time （36 hours）.The size of stomatal cell of induced plants was increased but the density was decreased,the chromosome number of induced plants was 2 n=4 x=48,while that of diploids was 2 n=2 x=24.The sensitivity of Physalis pubescens L.varieties to colchicine were different,‘Tiebaqing’was more sensitive to colchicine,the optimal treatment conditions were germinated seeds soaked in 100 mg·L-1 colchicine for 12 hours,the phenotypic variation rate at 30 days were 8.67%;‘Dahuang’and‘Lilitian’were less sensitive to colchicine,the optimal treatment conditions were germinated seeds soaked in200 mg·L-1 colchicine for 12 hours,the phenotypic variation rate at 30 days were 6.33% and6.67%.Many mutant strains were identied to be mixed ploidy by flow cytometry,flow cytometry could accurately identify the ploidy of mutant strains in the early stage,and reduce the impact of mixed ploidy in breeding.