Monfort W S, Kirkpatrick T L, Rothrock C S, Mauromoustakos A
Rice Research and Extension Center, University of Arkansas, 2900 Highway 130 East, Stuttgart, AR 72160 Southwest Research and Extension Center, University of Arkansas, 362 Highway 174 North, Hope, AR 71801 Department of Plant Pathology, University of Arkansas, Fayetteville, AR 72701 Agricultural Statistics Laboratory, University of Arkansas, Fayetteville, AR 72701.
J Nematol. 2007 Mar;39(1):1-8.
The effect of various edaphic factors on Meloidogyne incognita population densities and cotton yield were evaluated from 2001 to 2003 in a commercial cotton field in southeastern Arkansas. The 6.07-ha field was subdivided into 512 plots (30.5 m x 3.9 m), and each plot was sampled for M. incognita prior to fumigation (Ppre), at planting (Pi), at peak bloom (Pm) and at harvest (Pf) each year. Soil texture (percent sand fraction) and the pre-plant soil fertility levels each year were determined from each plot. To ensure that a range of nematode population densities was available for study, 1,3-dichloropropene was applied in strips (3.9-m wide) at rates of 14.1, 29.2 and 42.2 liter/ha (128 plots each) each year 2 wk prior to planting. Data were evaluated using both stepwise and multiple regression analyses to determine relationships among edaphic factors, nematode population densities and yield. Although Pi and the percent sand fraction of the soil were the most important factors in explaining the variation in cotton yield, regression models only accounted for <26% of the variation in yield. When the same data were evaluated on a more homogeneous large-scale platform based on similar geographic locations, soil types and nematicide treatments, regression models that included both Pi and sand content explained 65%, 86% and 83% of the variability in yield for 2001, 2002 and 2003, respectively. Prediction profiles of the combined effects also demonstrated that damage potential for M. incognita on cotton in this study varied by soil texture.
2001年至2003年期间，在阿肯色州东南部的一个商业棉田中评估了各种土壤因素对南方根结线虫种群密度和棉花产量的影响。这个6.07公顷的田地被细分为512个地块（30.5米×3.9米），每年在熏蒸前（Ppre）、种植时（Pi）、盛花期（Pm）和收获时（Pf）对每个地块进行南方根结线虫采样。每年从每个地块测定土壤质地（砂粒百分比）和种植前土壤肥力水平。为确保有一系列线虫种群密度可供研究，在每年种植前2周，以14.1、29.2和42.2升/公顷的用量（各128个地块）在条状区域（3.9米宽）施用1,3 - 二氯丙烯。使用逐步回归分析和多元回归分析对数据进行评估，以确定土壤因素、线虫种群密度和产量之间的关系。尽管Pi和土壤砂粒百分比是解释棉花产量变化的最重要因素，但回归模型仅解释了不到26%的产量变化。当基于相似地理位置、土壤类型和杀线虫剂处理在一个更均匀的大规模平台上评估相同数据时，包含Pi和砂含量的回归模型分别解释了2001年、2002年和2003年产量变异性的65%、86%和83%。综合效应的预测曲线还表明，本研究中南方根结线虫对棉花的潜在危害因土壤质地而异。
