Invinsa Application to Reduce Water Stress Effects on Corn Growth and Yield at Maricopa, AZ, 2012

Abstract

Invinsa blocks ethylene perception by plants and can reduce the negative effects of water stress on crop growth. The objective of this study is to measure the effect on corn growth and yield of Invinsa application at incipient water stress. A study was conducted at the University of Arizona Maricopa Agricultural Center where Invinsa was applied on 15 May in blocks with adequate or deficit irrigation. The deficit irrigation block received no irrigation water for 7 days past incipient stress beginning on 15 May, but otherwise received adequate water during the other parts of the season. Invinsa had little or no effect on crop growth measured at five different dates during the growing season. Invinsa had no effect on grain yield, grain moisture content, harvest index, ear number, kernels per ear, kernel weight, and silking date. We were not able to measure an effect of Invinsa on photosynthetic rate, conductance to water, intercellular CO2 concentration, vapor pressure deficit, or leaf temperature. However, Invinsa increased daily water use at various time periods, particularly in the adequate irrigation regime. The lack of a response this year to Invinsa, other than water use, is similar to the results from last year where no consistent response was measured. Invinsa has increased corn yield in other regions, and heat and/or water stress at the Maricopa may mask the effects of Invinsa or render it ineffective.