Review of Irrigation Timing Stufies Conducted in 1995 and 1996

Abstract

Timing of the first, post plant irrigation is a critical management decision. With the more common reduced season type varieties being grown today water management becomes increasingly important and water stress must be avoided in order to obtain optimum yields In an effort to look at the effects of the timing of the first post plant irrigation two studies were established at both the Maricopa Ag. Center and the Marana Ag. Center in 1995 and 1996. Two treatments were established based upon evapotranspiration and soil water depletion with treatment one being the optimum irrigation timing and treatment two being delayed by approximately 7-10 days. Results showed decreased plant vigor and fruit retention as a result of the delayed irrigation treatment that continued the entire season. Yield reductions associated with the delayed irrigation were also observed in all four site years, two of which were significant.