Alves Tavvs M, Macrae Ian V, Koch Robert L
Department of Entomology, University of Minnesota, 1980 Folwell Ave., Saint Paul, MN 55108.
Department of Entomology, University of Minnesota, Northwest Research and Outreach Center, 2900 University Ave., Crookston, MN 56716.
J Econ Entomol. 2015 Dec;108(6):2655-64. doi: 10.1093/jee/tov250. Epub 2015 Aug 19.
Soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is the most economically important insect pest of soybean in the north central United States. Scouting-based integrated pest management (IPM) programs could become more efficient and more widely adopted by using plant spectral reflectance to estimate soybean aphid injury. Our objective was to determine whether plant spectral reflectance is affected by soybean aphid feeding. Field trials were conducted in 2013 and 2014 using caged plots. Early-, late-, and noninfested treatments were established to create a gradient of soybean aphid pressure. Whole-plant soybean aphid densities were recorded weekly. Measurements of plant spectral reflectance occurred on two sample dates per year. Simple linear regression models were used to test the effect of cumulative aphid-days (CAD) on plant spectral reflectance at 680 nm (RED) and 800 nm (NIR), normalized difference vegetation index (NDVI), and relative chlorophyll content. Data indicated that CAD had no effect on canopy-level RED reflectance, but CAD decreased canopy-level NIR reflectance and NDVI. Canopy- and leaf-level measurements typically indicated similar plant spectral response to increasing CAD. CAD generally had no effect on relative chlorophyll content. The present study provides the first documentation that remote sensing holds potential for detecting changes in plant spectral reflectance induced by soybean aphid. The use of plant spectral reflectance in soybean aphid management may assist future IPM programs to reduce sampling costs and prevent prophylactic insecticide sprays.
大豆蚜，即豆蚜（半翅目：蚜科），是美国中北部大豆最具经济重要性的害虫。基于田间巡查的综合虫害管理（IPM）计划若利用植物光谱反射率来估算大豆蚜危害，可能会变得更高效且更广泛地被采用。我们的目标是确定植物光谱反射率是否受大豆蚜取食影响。2013年和2014年使用笼罩小区进行了田间试验。设置了早期、晚期和未受侵染处理，以形成大豆蚜压力梯度。每周记录全株大豆蚜密度。每年在两个采样日期进行植物光谱反射率测量。使用简单线性回归模型来测试累积蚜日（CAD）对680纳米（红光）和800纳米（近红外）处的植物光谱反射率、归一化植被指数（NDVI）以及相对叶绿素含量的影响。数据表明，CAD对冠层水平的红光反射率没有影响，但CAD降低了冠层水平的近红外反射率和NDVI。冠层和叶片水平的测量通常表明植物光谱对CAD增加的响应相似。CAD一般对相对叶绿素含量没有影响。本研究首次证明遥感技术在检测大豆蚜引起的植物光谱反射率变化方面具有潜力。在大豆蚜管理中使用植物光谱反射率可能有助于未来的IPM计划降低采样成本并避免预防性杀虫剂喷洒。
