Impact of Water Stress on Maize Grown Off‐Season in a Subtropical Environment

Abstract

During the last decade, the production of off-season maize has increased in several regions of Brazil. Growing maize during this season, with sowing from January through April, imposes several climatic risks that can impact crop yield. This is mainly caused by the high variability of precipitation and the probability of frost during the reproduction phases. High production risks are also partially due to the use of cultivars that are not adapted to the local environmental conditions. The goal of this study was to evaluate crop growth and development and associated yield, yield components and water use efficiency (WUE) for maize hybrids with different maturity ratings grown offseason in a subtropical environment under both rainfed and irrigated conditions. Three experiments were conducted in 2001 and 2002 in Piracicaba, state of Sa˜o Paulo, Brazil with four hybrids of different maturity duration, AG9010 (very short season), DAS CO32 and Exceler (short season) and DKB 333B (normal season). Leaf area index (LAI), plant height and dry matter were measured approximately every 18 days. Under rainfed conditions, the soil water content in the deeper layers was reduced, suggesting that the extension of the roots into these layers was a response to soil water limitations. On average, WUE varied from 1.45 kg m )3 under rainfed conditions to 1.69 kg m )3 under irrigated conditions during 2001. The average yield varied from 4209 kg ha )1 for the hybrids grown under rainfed conditions to 5594 kg ha )1 under irrigated conditions during 2001. Yield reductions under rainfed conditions were affected by the genotype. For the hybrid DKB 333B with a normal maturity, yield was reduced by 25.6 % while the short maturity hybrid Exceler was the least impacted by soil water limitations with a yield reduction of only 8.4 %. To decrease the risk of yield loss, the application of supplemental irrigation should be considered by local farmers, provided that this practice is not restricted by either economic considerations or the availability of sufficient water resources.

Productivity and nitrogen use of maize as affected by in situ and ex situ green manuring in major and minor seasons of tropical Asia

“…Most rainfed crops are adversely affected in this season, and hence vegetative growth is retarded, while the plants produce flowers earlier, as seen in days to 50% anthesis. This could be attributed to the early maturing of maize under higher temperature and lower moisture conditions (Soler et al, 2007).…”

Differential responses of maize yield to drought at vegetative and reproductive stages

“…Drought is known to affect morphology, photosynthesis, and dry matter (DM) accumulation as well as grain yield and the nutritional composition of maize (Çakir 2004, Soler et al 2007, Hao et al 2016, Gheysari et al 2017. It is widely recognized that maize is sensitive to drought throughout the growing season, especially during its reproductive stages (Denmead and Shaw 1960, Grant et al 1989, Çakir 2004, Saseendran et al 2014).…”

The effects of different water and nitrogen levels on yield, water and nitrogen utilization efficiencies of spinach (Spinacia oleraceaL.)

“…Many researchers found water deficit reduced leaf area (Pandey et al 2000), plant height (Soler et al 2007), shoot growth (Stone et al 2001), and plant yield (Payero et al 2006). However, over-irrigation can increase agricultural salinization and cause the destruction of agriculture lands (Skaggs et al 2006).…”