Production of Corn with Water Stress at Different Stages of Development

Abstract

Corn is a crop of high potential for grain production and it is also highly sensitive to environmental deficiencies. Water availability is the main environmental limiting factor that Uruguay presents to corn development, due to low water storage capacity of the soil, high atmospheric demands and irregular rainfall. The work consisted in determining the yields of corn in situations of water wellness (T1), and quantify the decreases generated by the occurrence of water stress during: the critical period (CP) (T2), grain filling (T3), and vegetative stage and CP (T4); it was also evaluated a witness in rainfed (T5). Water stress was generated at various stages through drought simulators and water wellness by supplementary irrigation. The results showed that the yield without water deficiencies was between 13,5 and 15,3 t ha^-1 approximately. Water deficiencies during CP caused losses of approximately 50% of the potential yield. Water stress at grain filling caused generated yield reductions close to 30%, and the deficiencies accumulated in the vegetative stage and CP caused a decline of 56%.