Preliminary Study On Anther Culture And Plant Regeneration Of Sweet Potato

Sweet potato [Ipomoea batatas(L.)Lam.] is an important and high-efficiency food crop widely cultivated in China.Due to its high genetic heterozygosity and self-incompatibility,traditional breeding methods are inefficient.Anther culture can obtain pure lines by inducing embryoid,thereby improving the breeding efficiency.In this study,three sweet potato varieties,‘Jifen 2’,‘Guangshu 15-156’ and ‘Violet’ were used as test materials,and the anther culture regeneration system of sweet potato was established by studying the influencing factors of anther callus induction and plant regeneration.The results of the study were as follows:1.The microspore development period has a certain corresponding relationship with the flower organ morphology.The characteristics of the microspores in the mononucleate stage of the three sweet potato varieties were as follows: the top of the calyx was dehided,the longitudinal diameter of the flower bud was 9.30-9.41 mm,the transverse diameter of the flower bud was 2.52-2.53 mm,and the length of the anther was 1.29-1.46 mm,and the color was white-green.2.When the microspores were in the mononuclear stage,the three varieties had the highest callus induction rate;The best pretreatment method for anther callus induction of the three varieties was pretreatment at low temperature at 4℃ for 2 days,followed by heat shock treatment at 35℃ for 7 days after inoculation;Three varieties use MS as the best basic medium;The optimum sucrose concentration for the induction culture of anther callus of the three varieties was 3%-6%;The best callus induction medium for‘Jifen 2’,‘Guangshu 15-156’ and ‘Violet’ were MS+2 mg/L2,4-D+3 mg/L6-BA,MS+3mg/L2,4-D+1 mg/L6-BA and MS+3 mg/L2,4-D+3 mg/L6-BA,the callus induction rates were 48.90%,65.22% and 33.33%,respectively.3.The best callus differentiation medium for ‘Jifen 2’ was MS+1 mg/L6-BA+0.2mg/LNAA,the differentiation rate was 11.11%,and adventitious shoots did not take root.The best callus differentiation medium for ‘Guangshu 15-156’ and ‘Violet’ was MS+1 mg/LKT+0.2 mg/LNAA,and the differentiation rates were 19.23% and 38.10%,respectively.The most suitable rooting medium for adventitious buds was MS+0.1mg/LNAA,the rooting rates were 83.33% and 90.90%,respectively.4.The calli of ‘Jifen 2’ were mainly hexaploid,accounting for 97.92%,chimera accounted for 2.08%,and no regenerated plants;the calli of ‘Guangshu 15-156’ were mainly hexaploid,accounting for 87.50%,and chimera accounted for 8.33%,aneuploid accounted for 4.17%,and the regenerated plants were hexaploid;the calli of ‘Violet’were mainly hexaploid,accounting for 95.83%,chimera accounted for 2.08%,aneuploid accounted for 2.08%,and the regenerated plants were hexaploid.