Understanding variability associated with corn grain yield response to foliar fungicide application

Strobilurin;Corn

Marshall, John ; Below ; Frederick E.

关键词: Strobilurin;    Corn;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/49587/John_Marshall.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Quinone outside inhibitor (QoI) fungicide (e.g., pyraclostrobin, azoxystrobin, andtrifloxystrobin) fungicide application is becoming a common practice in corn productionsystems. The strobilurin class of fungicides inhibits mitochondrial respiration in fungal cells, andpreventing plant pathogen infection. In addition, these compounds have been shown to decreaseethylene biosynthesis and reduce oxidative stress in plants. Yield response to fungicideapplication tends to be highly variable as a result of varying disease pressure, but may also beaffected by environmental factors and management practices that influence corn yield potential.The focus of this research was to determine if there is a differential yield response to strobilurinfungicide application under standard and intensive management systems. The standardmanagement system in this study consisted of crop input levels that are consistent with currentuniversity recommendations (i.e., adequate soil fertility, 180 lb N, and a plant density of 32,000plants per acre). In contrast, the intensive management system consisted of extra P fertility, extraside-dress N, a plant density of 45,000 plants per acre, and application of a strobilurin fungicideduring the tassel stage. Treatments were designed to assess the yield difference associated withadding a fungicide treatment to the standard and intensive management system. A combinedanalysis of 30 site-years (2009 to 2013) indicated that adding a fungicide application to the basicsystem did not result in a significant yield increase (+3.5 bushels per acre; P = 0.17), while theaddition of fungicide in the intensive system led to a 8.8 bushel per acre increase in yield (P <0.01). Individual data sets contributing to the overall analysis were divided into three groupsbased on their mean yields (150 to 175, 175 to 200, and greater than 200 bushels per acre) toinvestigate the influence of yield potential on fungicide response. In general, response tofungicide increased as the yield potential of an environment increased, especially for theiiiintensive management system. The results of this research could provide corn producers a valuable guide to determine if strobilurin fungicide application is warranted based on the estimated yield potential of their crop and other contributing factors like management system.