Abstract
ABSTRACT Global climate change tends to intensify water unavailability, especially in semi-arid regions, directly impacting agricultural production. Cowpea is one of the crops with great socio-economic importance in the Brazilian semi-arid region, cultivated mainly under rainfed farming and considered moderately tolerant to water restriction. This species has physiological and biochemical mechanisms of adaptation to these stress factors, but there is still no clear vision of how these responses can not only allow survival, but also ensure yield advances in the field. Besides acclimation mechanisms, the exogenous application of abiotic (salicylic acid, silicon, proline, methionine, and potassium nitrate) and biotic (rhizobacteria) elicitors is promising in mitigating the effects of water restriction. The present literature review discusses the acclimation mechanisms of cowpea and some cultivation techniques, especially the application of elicitors, which can contribute to maintaining crop yield under different water scenarios. The application of elicitors is an alternative way to increase the sustainability of production in rainfed farming in semi-arid regions. However, the use of eliciting substances in cowpea still needs to be carefully explored, given the difficulties caused by genotypic and edaphoclimatic variability under field conditions.
Highlights
Semi-arid region has a high variation in the pattern and total annual rainfall, as well as high levels of solar radiation and air temperature
The stress tolerance mechanisms and use of elicitors to mitigate the effects of water deficit on cowpea are discussed, focusing on physiological and biochemical processes, especially those related to osmotic adjustment and antioxidant metabolism
In cowpea under water restriction, proline synthesis induction can increase the osmolyte concentration by more than 100% (Silva et al, 2019; Andrade et al, 2021), which confirms its importance in maintaining the cell water status of this species
Summary
Semi-arid region has a high variation in the pattern and total annual rainfall, as well as high levels of solar radiation and air temperature. The joint action of biotic and abiotic elicitors under stress conditions, such as the inoculation of Bradyrhizobium plus the foliar application of salicylic acid (SA), is an efficient strategy to maintain leaf water status and plant growth, mediated by increasing the concentration of osmoregulators and antioxidant enzymes activity (Andrade et al, 2021) This interaction is positive and suggests a good joint action of these two factors mitigating the effects of water deficit and increasing cowpea drought tolerance. To surpass the effects of water restriction, in addition to cowpea’s endogenous apparatus, it has been demonstrated that the exogenous application of biotic and/ or abiotic elicitors agents can increase secondary metabolism and induce a wide range of defense mechanisms in plants to improve drought tolerance Under such circumstances, it is relevant to develop procedures that increase the yield of the crop at a low cost so that it can, at the same time, be profitable to the farmer and accessible to the entire population
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call