Water-Yield Relations of Several Spring-Planted Dryland Crops following Winter Wheat

Abstract

A winter wheat (Triticum aestivum L.)-fallow cropping system has developed in the central Great Plains as a means to stabilize crop production in a highly variable climate. As an alternative, a flexibIe cropping system partially based on soil water at planting may allow producers to minimize risk while allowing some additional crop production during wetter climate cycles. Water-yield relations are critical in the development of flexible cropping systems. The experiment was conducted near Sidney, NE, on a Keith silt loam (fine silty, mixed mesic Aridic Argiustoll) to determine the response of five spring-planted crops (corn (Zea mays L.), grain sorghum [Sorghum bicolor (L.) Moench], pinto bean (Phaseolus vulgaris L.), proso millet (Panicum miliaceum L.), and sunflower (Helianthus annuus L.)) to three different soil water levels the year following winter wheat harvest. Water use of all crops increased with increasing soil water at planting. The grain yield of pinto bean and proso millet responded positively to soil water at planting. Soil water at planting accounted for less than half of the total variability in grain yield for corn, grain sorghum, and sunflower. Soil water at planting appears to be useful in determining the success of planting the two short duration crops (pinto bean and proso millet) the year after winter wheat harvest. For the long duration crops (corn, grain sorghum, and sunflower) other factors, such as precipitation near the time of flowering, may be more important in determining success