Corn and Soybeans Response to Different Water Availability at Various Stages of Crop Development
Corn and soybean crops differ in both their physiological processes and their environmental requirements. However, water availability during the development cycle is the main environmental factor that determines yields and their variability in rainfed crops. The work was carried out in the irrigation field of the «Dr. Mario A. Cassinoni» Experimental Station of the School of Agronomy located in Paysandú, Uruguay, during 2011 and 2012 seasons. The main objective was to quantify the impact of water deficiencies on corn and soybean yields at different stages of development. In order to do this, water deficiencies and water-comfort conditions were induced at different stages of the crops through interception of precipitation (PP) and supplemen-tary irrigation so as to control the available water (AW). Results showed that the largest decreases in yields occurred when water deficiencies accumulated in the vegetative stages and in the critical period (CP) varying from 40 % in corn and 30 % in soybeans, in comparison to the control treatments which presented yields of 14,6 t ha-1 and 6,2 t ha-1, respectively.