Evaluation of Selected Nonfumigant Nematicides on Increasing Inoculation Densities of Meloidogyne incognita on Cucumber
Evaluation of Selected Nonfumigant Nematicides on Increasing Inoculation Densities of Meloidogyne incognita on Cucumber
复制标题
DOI：
10.1094/pdis-04-19-0836-re
复制
发表时间：
2019-12-01
期刊：
影响因子：
4.5
通讯作者：
Timper, Patricia
中科院分区：
文献类型：
--
作者：
Hajihassani, Abolfazl;Davis, Richard F.;Timper, Patricia
南方根结线虫是一种南方根结线虫，由于其对南方根结线虫的感病能力较强，对南方根结线虫的防治尤为困难。种植者通常依赖杀线虫剂来控制RKN。通过两个微区试验，研究了4种非熏蒸杀线虫剂恶霉灵、氟虫胺、氟苯磺隆和氟虫净在不同接种密度(1,000、5,000、10,000和20,000条/微区)下接种黄瓜，对降低黄瓜根癌严重程度和采后土壤线虫数量的效果，并提高了黄瓜的生长和产量。除氟磺隆在黄瓜移栽前7天施药外，其余3种药剂均在黄瓜移栽前1天施药。在收获时，根癌指数在不同接种密度和杀线剂之间差异显著(P<；0.0001)。在所有接种密度下，与未处理对照相比，四种杀线虫剂均能有效降低根癌指数。在最低接种密度下，不同杀线虫剂的虫胆指数和最终种群密度没有显著差异，但随着线虫接种密度的增加，虫胆指数增加。虫害指数与接种密度的相关性表明，氟磺隆、氟菌灵或氟虫草胺处理的土壤在降低虫害严重程度方面比恶草胺处理更有效。回归分析也表明，线虫接种密度对这些杀线虫剂处理的黄瓜产量没有显著影响。本研究结果将为提高不同RKN接种密度土壤中的杀线虫效果提供指导。
The southern root-knot nematode (RKN), Meloidogyne incognita, is particularly difficult to manage because of high susceptibility of all commercial cucumber (Cucumis sativus) cultivars to this nematode. Growers have conventionally relied on nematicide applications to control RKN. Two microplot experiments were conducted in which four nonfumigant nematicides, oxamyl, fluopyram, fluensulfone, and fluazaindolizine, were examined for their efficacy in reducing gall severity and postharvest soil nematode numbers in microplots inoculated with increasing inoculation densities (1,000, 5,000, 10,000, and 20,000 nematodes/microplot), and improving growth and yield of cucumber. Nematicides were applied 1 day prior to transplanting cucumber seedlings, except fluensulfone, which was applied 7 days before transplanting. At harvest, root gall indices differed significantly (P < 0.0001) among nematode inoculation densities and nematicides. All four nematicides were effective in reducing the root gall index when compared with the untreated control on a consistent basis at all M. incognita inoculation densities. At the lowest inoculation density, no significant difference in gall index or final population density was observed among nematicides; however, gall index increased with increasing nematode inoculation densities in nematicide-treated microplots. Correlations between gall index and inoculation density clearly showed that soil treatment with fluensulfone, fluazaindolizine, or fluopyram was more effective in reducing gall severity than treatment with oxamyl. Regression analysis also indicated no significant effect of nematode inoculation densities on yield of cucumber treated with these nematicides. Results of this study will provide guidance for improving nematicide efficiencies in soil with varying inoculation densities of RKN.