热处理结合茎尖培养去除甘薯丛枝病植原体

Obtaining sweet-potato phytoplasma-free plantlets by heat treatment and apical culture

以甘薯丛枝病试管苗病株为材料，用热处理结合茎尖培养法对甘薯丛枝病病株进行了去除植原体 的研究。结果表明，０． ５ ｍｍ以下茎尖培养可以去除植原体，茎尖越小，去除植原体的效果越好，但成苗率降低； ０．８ ｍｍ以上茎尖培养不能去除植原体，但是成苗率较高。（３９±１）℃高温连续处理２～３周后，剥取茎尖培养可以 提高去除植原体的效率，对成苗率影响不大，热处理时间越长，去除植原体效果越好，但被处理的试管苗易死亡。甘 薯丛枝病试管苗在（３９±１）℃高温下，以处理３周为宜。

Taking the sweet potato witche's-broom plantlets (tissue culture) as the material,the study of obtaining sweet potato witche's broom-free plantlets by the method of heat treatment and apical culture was carried out. The results showed that apical culture can eliminate the phytoplasma when the size of apical was less than 0. 5 mm,however,when the size of apical is more than 0. 8 mm,it can't eliminate the phytoplasma thoroughly. The rate of plantlet formation had close relation with the size of the excised apical. The bigger the apical was,the higher was the rate of plantlets formation. But the rate of phytoplasmafree plantlets had negative relation with the size of the excised apical. The infected sweet potato test-tube plantlets were treated with (39±1 )℃ for 2- 3 weeks,then the apicals were excised for culturing in vitro. It was efficient to increase the rate of phytoplasma-free plantlets (it reached 70% ) pretreated with heat. At the same time,plantlet formation had no relation with the treatment time,it was only related to the size of excised apical. To sum up,heat treatment and apical culture method is worth while in production of Phytoplasma-free sweet potato plantlets.