International Institute of Tropical Agriculture, Nairobi, Kenya.
Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI 53706, U.S.A.
Plant Dis. 2022 Nov;106(11):2904-2910. doi: 10.1094/PDIS-09-21-1888-RE. Epub 2022 Oct 5.
Models were developed to quantify the impact of to the early season growth and yield of soybean in field and greenhouse environments and to estimate yield loss because of . in Wisconsin. There was a negative linear relationship between initial nematode population densities () and shoot and total plant weight at V2 and yield, pod number, seed number, and seed mass at harvest in the field. Relative yield loss, modeled for the second year of the field experiment, suggested a loss of 4.5% for yield and between 2.4 and 2.8% for yield components at the mean field value. Negative linear relationships were demonstrated for the relative loss in those variables as well as for harvest index and shoot, root, and total plant weight at harvest in the greenhouse. Stress imposed by . began within 2 weeks after planting and continued through harvest. Estimates of the percent loss attributed to each nematode value were 0.020% for yield, 0.015% for pod number, and 0.017% for seed number. spp. was the most widely prevalent pest nematode among samples submitted to a statewide nematode testing program. Molecular identification of a subset of 63 samples suggested 15% were infested with . at a mean value of 197 . per 100 cm soil. Yield loss because of . , estimated from prevalence data and our empirical greenhouse model, ranged from 0.23 to 2.76% among Wisconsin's agricultural districts. The cumulative impact for all spp. is likely much greater, given this loss estimate does not account for the monoecious species present in 79% of the samples.
模型被开发出来，以量化在田间和温室环境中对大豆早期生长和产量的影响，并估计由于线虫造成的产量损失。在威斯康星州，线虫初始种群密度（）与 V2 时的茎和总植物重量以及田间收获时的产量、荚数、种子数和种子质量呈负线性关系。田间试验第二年的相对产量损失模型表明，产量损失 4.5%，平均田间值的产量构成因子损失 2.4%至 2.8%。在温室中，这些变量的相对损失以及收获指数和茎、根和总植物重量也表现出负线性关系。线虫的胁迫在种植后 2 周内开始，并持续到收获。估计每个线虫值造成的损失百分比分别为：产量损失 0.020%，荚数损失 0.015%，种子数损失 0.017%。根结线虫是向全州线虫检测计划提交的样本中最普遍的害虫线虫。对 63 个样本子集的分子鉴定表明，15%的样本感染了线虫，平均每 100 厘米土壤中有 197 条线虫。由于线虫，估计从流行率数据和我们的经验温室模型得出的产量损失在威斯康星州的农业区范围从 0.23%到 2.76%。鉴于这个损失估计没有考虑到 79%的样本中存在的雌雄同体物种，所有根结线虫的累积影响可能更大。
