Response of Dry Beans to Daily Deficit Sprinkler Irrigation1

Abstract

AbstractDry beans (Phaseolus vulgaris L.) are an important irrigated crop in the Pacific Northwest, but no information is available as to their water requirements under high‐frequency sprinkler irrigation. The present study was conducted to evaluate the response of dry beans to variable amounts of water applied daily by sprinkler, as affected by soil water‐holding capacity. Studies were conducted on a Warden loam (coarse‐silty, mixed, mesic Xerollic Camborthids) near Prosser, Wash., and on a Quincy sand to loamy sand (mixed, mesic Xeric Torripsamments) near Paterson, Wash. Beans were irrigated uniformly by solid‐set sprinklers until near the time of full canopy, when irrigation variables were initiated and continued until harvest. At harvest yields of vines, clean beans, and seed weight were determined. On the loam soil yields were not reduced when daily sprinkler irrigation was much less than estimated evapotranspiration (ET). It was concluded that no more than 10 to 15 cm of water need be applied from full cover until harvest. On the sandy soil, yields increased with water applied up to the equivalent of nearly 100% estimated ET. On the sandy soil, with limited water holding capacity, it is not possible to reduce irrigation to much below estimated ET without loss in yield.