Production and biochemical responses of cowpea under thermal and water stress

Abstract

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.

Cowpea Yield Under Water Stress Scenarios

“…This indicator, as explained by Sinclair (1998), is the most Water use efficiency (WUE) and grain yield were directly affected by the cropping season, which was already expected, since the rainy season had more precipitation than the dry season, in addition to lower values of temperature and solar radiation. Barros et al (2021) explain that the availability of water promotes greater water use efficiency, consequently higher yield of cowpea, but this efficiency is limited by water deficit and high temperature.…”

Salicylic acid improves cowpea productivity under water restriction in the field by modulating metabolism

“…Water deficits can promote a series of physiological and morphological changes in cowpea plants, depending on the intensity, phenological stage, and cultivar resistance ( Melo et al., 2022 ). During the reproductive phase, a water deficit can result in flower and pod loss, decreasing the number of pods per plant ( Barros et al., 2021 ); this effect was observed in the BRS Novaera and BRS Pajeú cultivars ( Figure 10A ). For the BRS Pujante cultivar, the water deficit reduced NPP and impacted the production of photoassimilates necessary for grain production ( Figure 10B ), this result is corroborated by Martins et al.…”