腐烂茎线虫在马铃薯不同组织中的数量动态

腐烂茎线虫病是近年来我国马铃薯生产中的一种新病害, 了解腐烂茎线虫的侵染规律对该病害的预防和控制及对马铃薯产量和品质提高具有重要意义。本研究采用盆栽法, 在苗期接种腐烂茎线虫, 研究该线虫在马铃薯不同组织中的数量动态及危害程度。结果显示, 在发芽-幼苗期(播种0 ~ 75 d), 母薯先受到腐烂茎线虫侵染; 在发棵期(播种75 ~ 90 d), 母薯和匍匐茎均检测到腐烂茎线虫; 在结薯期到成熟期(播种90 ~ 105 d), 线虫开始危害新生块茎, 随着块茎膨大危害逐渐加重。在马铃薯成熟期, 症状表现最明显, 新生块茎中线虫数量最多, 可达767.67条/g。不同时期的接种试验表明, 在匍匐茎形成期(播种后70 d)接种, 马铃薯受害最为严重, 发病率达100%, 块茎中线虫密度最高, 达到99.32条/g, 且块茎鲜重最低, 为14.02 g/个。本研究结果可为马铃薯腐烂茎线虫的适时有效防治提供参考。

Quantity dynamics of Ditylenchus destructor in different tissues of the potato plant

Stem rot nematode disease is a new disease in potato production in China in recent years. Understanding the infection rules of this disease is of great significance for effective prevention and control, and can improve potato quality and yield. In this study, Ditylenchus destructor was inoculated at the seedling stage in pots to investigate the quantity dynamics and damage degrees. The results showed that the mother tuber was infected firstly by nematodes at the seedling stage (0 to 75 days after sowing). At the tillering stage (75 to 90 days after sowing), both the mother tubers and stolons were infected. From the tuber forming stage to the maturity stage (90 to 105 days after sowing), nematodes began to harm the young tubers, and the damage gradually increased with the growth of the tubers. The symptoms on tubers were the most severe at the maturity stage with the largest numbers of nematodes in new tubers, up to 767.67 nematodes per gram. The inoculation results at different periods showed that when inoculated at the seedling stage (70 days after sowing), the potato suffered the most serious damage. The incidence rate reached 100%, the fresh weight of tubers was the lowest with 14.02 g per tuber, and the density of nematodes in the tuber was the highest, with 99.32 nematodes per gram. This above results can provide reference for timely and effective control of stem rot nematodes on potato.