蜜薯的脱毒培养及脱毒苗的生理变化

Virus-free culture of sweet potato and physiological changes of virus-free seedlings

为探索脱毒对甘薯生理生化特性的影响,以云南高原蜜薯为试验材料,以0.1~0.2 mm微茎尖为外植体,研究外源激素对茎尖分生组织培养的影响,建立云南高原蜜薯脱毒繁育体系。同时对脱毒甘薯生长过程中的形态学指标、光合指标、营养成分、生物活性成分以及相关保护酶的活性等指标进行测定。结果表明:MS+0.1 mg·L^(-1)-6-BA+0.1 mg·L^(-1) NAA+30 g·L^(-1)蔗糖+7 g·L^(-1)琼脂是甘薯茎尖脱毒培养的最佳体系;脱毒苗的生长动态指标均优于对照,光合能力、营养指标及生物活性成分均高于对照;脱毒处理增加了甘薯叶片中POD、SOD等保护酶的活性,降低了MDA含量。说明脱毒能显著改善甘薯植株的生长状况,各项生理指标均优于普通植株。该研究结果为生产上培养甘薯脱毒种苗以及脱毒苗的推广应用提供重要的理论依据。

To explore the effect of detoxification on the physiological and biochemical characteristics of sweet potato,Yunnan plateau sweet potatoes were taken as the experimental materials,0.1-0.2 mm micro stem tips were used as explants,and the effect of exogenous hormones on shoot tip meristem culture were studied to establish a virus-free breeding system.The morphological indexes,photosynthetic indexes,nutrient content,functional component and related protective enzyme activities of the sweet potato were determined.The results showed that the medium with MS+0.1 mg·L^(-1) 6-BA+0.1 mg·L^(-1) NAA+30 g·L^(-1) sucrose+7 g·L^(-1) agar was the best system for virus-free culture of the sweet potato shoot tips;the growth dynamic indexes of virus-free seedlings were better than those of the control,and the photosynthetic capacity,nutritional indexes and bioactive components were higher than those in ordinary seedlings;the activities of POD,SOD and other protective enzymes were increased,while the content of MDA was decreased in the virus-free sweet potato leaves.The results indicated that the physiological and biochemical indexes of virus-free seedlings were better than those of normal seedlings.The results can provide an important theoretical basis for the cultivation of virus-free sweet potato seedlings in production and the popularization and application of virus-free seedlings.