基于发根培养体系的甘薯品种抗线虫特性鉴定研究

利用发根农杆菌诱导的甘薯发根体系,鉴定甘薯品种抗线虫的特性。试验在甘薯品种徐薯18、栗子香和鲁78066诱导的发根体系上,接种马铃薯腐烂线虫,六周后调查发根繁殖线虫情况及线虫侵染发根情况,然后评价它们的抗线虫特性。结果表明:培养六周后,线虫在徐薯18、栗子香和鲁78066发根上繁殖倍数分别为8.82,0.76和0.70;在徐薯18发根上观察到多处线虫侵入位点,在栗子香和鲁78066发根上只观察到一处线虫侵入位点;基于以上结果,鉴定徐薯18为易感线虫病品种,栗子香和鲁78066为抗线虫病品种,徐薯18和鲁78066的鉴定结果和发病地自然诱发鉴定结果相一致,栗子香不同于发病地自然诱发鉴定结果。鉴定结果表明:用不同品种的甘薯发根作鉴定其抗线虫特性,具有体系简单、直观方便、重复性好以及不受自然环境影响等优点,进一步完善可以作为植物对线虫病抗性鉴定新的体系。

An Evaluation on the Resistance of Sweet Potato Cultivars to Nematode (Ditylenchus destructor)under the System of Hairy-roots Culture

A.rhizogenes was used to induce transgenic hairy roots on sweet potato,and to evaluate an in vitro sweet potato hairy root system for investigations of resistance to Ditylenchus destructor.Nematodes were inoculated on hairy roots of Xushu18,Lizixiang and Lu78066 cultivars,the evaluation on resistance of sweet potato cultivars to nematode by nematode reproduction on hairy-roots and nematode was observed inside the root tissue after 6 weeks.The results showed: the production rate of D.destructor was 8.82,0.76 and 0.70 after 6 weeks on sweetpotato hairy roots Xushu18,Lizixiang and Lu78066,nematodes were observed into Xushu18 root tissue at many sites,but lizixiang and Lu78066 root tissue at only one site.Xushu18 was susceptible cultivar to nematode,Lizixiang and Lu78066 were resistance cultivars to nematode.Evaluation on resistance to nematode of Xushu18 and Lu78066 cultivars accorded with natural infection in field,Lizixiang was out of accord with evalution by natural infection in field.The results of evaluation showed hairy roots induced by A.rhizogenes was a versatile,easy and reproducible system for testing nematode resistance,it will be a new system to evaluate the resistance of sweet potato cultivars to nematode to perfect it.