Production and biochemical responses of cowpea under thermal and water stress.

Water deficit and high temperature limit agricultural productivity, affecting plant growth, development, and metabolism. Thus, the objective of this study was to evaluate the impact of the interaction between water deficit and temperature increase on cowpea production. The experiment was carried out with the cultivar BRS Rouxinol, in growth chambers, in a 4 × 2 factorial arrangement, being four soil water availability (25; 50; 75 and 100% of field capacity) and two daily temperature regimes (T°1: 20-26-33 °C and T°2: 24.8-30.8-37.8 °C). The increase in water availability favored an increase in shoot and root dry mass. The vegetative stage was prolonged in plants maintained at a temperature regime of 24.8-30.8-37.8 °C. The cowpea yield increased with higher water availability. The water availability of 90% was the one that provided the highest water use efficiency. The 4.8°C increase in air temperature promotes an increase in oxidative stress with lack of synchrony in the antioxidative defense system. The cultivar Rouxinol is sensitive to the increase in air temperature and water deficit. However, even with 100% water availability, there was no seed production with an increase in air temperature.