叶原基形态对甘薯茎尖脱毒培养的影响

Effect of the Morphology of Leaf Primordium on Shoot Tip Virus-Free Culture in Sweet Potato(Ipomoea batatas L.)

以带有甘薯羽状斑驳病毒（SPFMV）的渝薯2号，从其块根萌芽上剥取2叶原基形态分别处于突起态、半闭合态和闭合态0．22～0．35mm大小的茎尖为外植体，培养于附加BAP与IAA，BAP与NAA不同激素体积质量分数组合的MS培养基上进行成苗培养，对应再生株系用硝酸纤维素膜酶联免疫吸附检测法（NCMELISA）进行病毒检测．结果表明：茎尖培养最佳的激素体积质量分数组合为0．8～1．4mg／L BAP＋0．01mg／LNAA，有利于茎尖基部发生少量的愈伤组织，芽粗壮且成苗快．成苗率因外植体而不同，闭合态和半闭合态较高，分别达92．9％和88．9％，而突起态成苗率仅为46．7％．脱毒效果也与外植体相关，最佳效果是叶原基突起态，其次是半闭合态和闭合态，分别获得100％，83．9％和71．9％的脱毒植株．

In this experiment, shoot tips 0.22--0.35 mm in size derived from the tuberous root buds of sweet potato cv. Yushu-2 infected by SPFMV with two protuberant, semi closed or closed leaf primordia were used as explants and cultured on MS media supplemented with BAP and IAA or BAP and NAA at different concentrations to obtain virus-free plantlets. Then nitrocellulose membrane-ELISA （NCM ELISA） was used for virus detection. The results indicated that the optimum combination of hormones for shoot tip culture was 0.8--1.4 mg/L BAP if- 0.01 mg/L NAA, and the regenerated sprouts were stronger and grew rapidly. The percentage of plantlet regeneration varied with explants, being 92.9 %, 88.9 ~//00 and 46.7~ form explants with closed, semi-closed and protuberant leaf primordial, respectively. At the same time, the percentage of virus-free plantlets also varied with explants, being 100%, 83.9% and 71.9% for protuberant, semi-closed and closed leaf primordial, respectively.