牛尾山药病毒病危害情况调查与茎段脱毒方法

Investigation on virus disease in‘Niuwei’yam and removal of virus with stem culture

为探究云南特色品种牛尾山药携带的病毒及其危害情况,明确病毒抑制剂、热处理和低温处理对山药病毒的脱毒效果,以期得到较好的脱毒方法。研究调查了牛尾山药病毒病发病率、植株病症,采用分子生物学方法检测了病毒种类,研究了不同脱毒处理下山药斑驳病毒的脱毒效果。结果表明:牛尾山药携带山药斑驳病毒,叶片可见明显的褪绿斑,发病率为41.67%~43.33%。RT-PCR检测结果显示,60 mol·L^(-1)盐酸吗啉胍处理、60 mol·L^(-1)利巴韦林药剂处理能降低山药成活率和生长量,但能有效脱除山药斑驳病毒。采用高温处理(45℃12 h、40℃24 h、45℃24 h)结合顶芽培养能有效脱除山药斑驳病毒,40℃处理24 h的山药生长量显著降低,而45℃处理12 h、45℃处理24 h的山药生长量和成活率均显著降低。低温处理(0℃24 h、5℃24 h)结合顶芽培养能显著降低山药成活率和生长量,但能有效脱除山药斑驳病毒。综合考虑成活率、生长量和脱毒效果,建议采用60 mol·L^(-1)盐酸吗啉胍处理或40℃高温处理24 h。

To investigate the virus carried by Yunnan s special variety of‘Niuwei’yam and its harmful effects,clarify the effectiveness of viral inhibitors,heat treatment,and low temperature treatment on removing virus from yam,with a view to obtaining better methods for devirusing.The study investigated the incidence of yam virus disease and plant symptoms in‘Niuwei’yam,and detected the type of virus using molecular biological detection method,and examined the detoxification effect of different treatments on yam mosaic virus.The results showed that‘Niuwei’yam carried yam mosaic virus,and obvious yellowing spots could be seen on its leaves.The incidence rate was 41.67%-43.33%.RT-PCR results showed that treatments with 60 mol·L^(-1) moroxydine hydrochloride or 60 mol·L^(-1) ribavirin could reduce the survival rate and growth of the yam but effectively remove the yam mosaic virus.High-temperature treatments(12 h at 45℃,24 h at 40℃,24 h at 45℃)combined with apical bud culture effectively removed yam mosaic virus.The treatment for 24 h at 40℃significantly reduced the growth of yam,while treatments for 12 h at 45℃and 24 h at 45℃significantly reduced both the growth and survival rate of yam.Low-temperature treatment(24 h at 0℃and 24 h at 5℃)combined with apical bud culture significantly reduced the survival rate and growth of yam but were effective in removing the yam mosaic virus.Considering the survival rate,growth,and detoxification effect,60 mol·L^(-1) moroxydine hydrochloride treatment or 40℃high-temperature treatment for 24 h was recommended.