禾谷孢囊线虫与不同小麦根系的互作表型特征

摘要

为了明确高抗品种‘华麦1号’的抗禾谷孢囊线虫机制，以 Pluronic F-127胶体为介质，比较了禾谷孢囊线虫2龄幼虫（J2）侵入根系前对抗病品种‘华麦1号’与感病品种‘豫麦34’和‘矮抗58’的根尖趋性差异，并采用室内人工接种法观察了线虫侵入3个品种后的发育进程。结果表明，J2对3个品种的根尖均表现明显的趋性，对‘矮抗58’的趋性最强，而对‘华麦1号’的最弱，接种4 h 和6 h 时‘华麦1号’与‘矮抗58’根尖吸引的线虫总量差异显著（P＜0．05）；组织染色观察到 J2对3个品种的根系均有一定数量的侵入，但高抗品种‘华麦1号’根系侵入的幼虫量和后期形成的白雌虫量均显著低于感病品种‘豫麦34’和‘矮抗58’。结果证实，‘华麦1号’的抗性机制主要表现为减少线虫的有效侵入量、抑制侵入后的线虫生长发育。%In order to understand the resistance mechanism of the wheat cultivar ‘Huamai No.1’to Heterodera avenae ,the difference between the resistant cultivar ‘Huamai No.1’,susceptible cultivar ‘Yumai No.34’and‘Aikang No.58’in root tips attracting second-stage juveniles (J2 s)of H .avenae were compared using Pluronic F-127 gel as a medium.The infection and development of J2 s in roots of the three cultivars were also observed through greenhouse inoculation test.The results showed that J2 s of H .avenae were able to be attracted by the root tips of the three cultivars.The attraction ability of ‘Huamai No.1’was stronger than that of ‘Aikang No.58’, with significant difference in the total number of J2 s attracted at 4 h and 6 h after inoculation (P <0.05).Tissue staining revealed that J2 s were capable to penetrate into the root system regardless of the cultivar resistance.How-ever,the amounts of J2 s that penetrated the root system and the white females produced in the root system of‘Huamai No.1’were significantly lower than those in ‘Yumai No.34’and ‘Aikang No.58’.The study suggested that the resistance mechanism of ‘Huamai No.1’might be decreasing the penetration of J2 s and suppressing the nematode development in the root system.