Search

The objective of this paper is to assess the impact of complementary irrigation on maize dry matter yield. A randomized complete design with 5 treatments and 4 replications was used. In order to schedule irrigations, the crop cycle was divided in three stages (pre-critical, critical and post-critical). Irrigation scheduling was based on a water balance calculated from weather data furnished by the meteorological station at the experimental field site. Irrigation was performed using lateral move pressurized systems. Maize matured in 138 days with all treatments and took 1660,6 degree days to attain physiological maturity. Dry matter yield showed significant differences (α = 0.05) among plots irrigated with the different treatments and between irrigated and control plots. Maximum production values ranged between 34,628 kg.ha-1 with T1 and 20,414 kg. ha-1 in the rain fed plots. The amount of water applied ranged between 360 and 300 mm; total crop water use, according to the water balance, was 575 mm ± 15 mm in the case of irrigated treatments, and 308 mm with the control treatments. Dry matter water use efficiency showed significant differences (α = 0.05) between irrigated treatments (5.7 kg.m-3) and rain fed (control) plots (6.6 kg.m-3). The harvest index was 0.49. [ABSTRACT FROM AUTHOR]

Maize (Zea mays L.) is one of the major crops grown in Humid Pampas of Argentina. The objective of this paper was to assess the impact of complementary irrigation on maize grain yield and its components. This research work was carried out during the 2001-2002 agricultural cycle at the experimental field site of the National University of Río Cuarto. A randomized complete design with 5 treatments and 4 replications was used. In order to schedule irrigations, the crop cycle was divided in three stages: pre-critical, critical and post-critical. Irrigation scheduling was based on a water balance. Grain yield showed no significant differences in the four irrigated treatments; however, there were significant differences ( α = 0.05) between irrigated and rain fed treatments. On average, grain yield with the irrigated treatments was 72 % higher than with the rain fed treatment. Yield components were greatly affected ( α = 0.05) by lack of irrigation. The amount of water applied ranged between 360 and 300 mm; total crop water use was 575 mm in the case of irrigated treatments, and 308 mm with the control. Grain water use efficiency, average, was 2.75 kg.m-3. [ABSTRACT FROM AUTHOR]