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

Igor Eneas Cavalcante; Alberto Soares de Melo; Rener Luciano de Souza Ferraz; Rayanne Silva de Alencar; Guilherme Felix Dias; Priscylla Marques de Oliveira Viana; Maurisrael Moura Rocha; Ashwell Rungano Ndhlala; Francisco Vanies da Silva Sá; Claudivan Feitosa de Lacerda; Pedro Roberto Almeida Viégas

doi:10.3389/fpls.2024.1415682

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

Front Plant Sci. 2024 Jul 2:15:1415682. doi: 10.3389/fpls.2024.1415682. eCollection 2024.

Affiliations

¹ Posgraduate Program in Agricultural Sciences, State University of Paraiba, Campina Grande, Paraíba, Brazil.
² Empresa Brasileira de Pesquisa Agropecuária, Pesquisa Agropecuária do Meio-Norte, Teresina, Piauí, Brazil.
³ Department of Plant Production, University of Limpopo, Sovenga, South Africa.
⁴ Posgraduate Program in Agricultural Engineering, Universidade Federal do Ceará, Fortaleza, Ceará, Brazil.
⁵ Department of Agronomy, Federal University of Sergipe, São Cristóvão, Sergipe, Brazil.

Abstract

Introduction: Salicylic acid has shown promise in alleviating water stress in cultivated plants. However, there is a lack of studies confirming its effectiveness in cowpea plants grown in field conditions. Therefore, this research aimed to evaluate the use of salicylic acid as a water stress mitigator in cowpea cultivars under different irrigation depths in field conditions.

Methods: Four cowpea cultivars (BRS Novaera, BRS Tapaihum, BRS Pujante, and BRS Pajeú) were subjected to different treatments: control (W100: 100% replacement of crop evapotranspiration - ETc), W50 (50% of ETc), W50+SA2 (50% of ETc + 276 mg L^-1 of SA), and W50+SA4 (50% of ETc + 552 mg L^-1 of SA). The treatments were combined in a 4×4 factorial scheme with three replications, arranged in a randomized block design.

Results: Water restriction had a negative impact on the water status, growth, gas exchange, and production of the cultivars while also leading to changes in the antioxidant metabolism and osmolyte concentration. The application of SA enhanced antioxidant activity and the synthesis of osmotic adjusters under stress conditions. The most effective concentration was 276 mg L^-1 in stage R2 and 552 mg L^-1 in stage V7, respectively. The BRS Pujante cultivar showed increased productivity under water restriction with SA application, while the BRS Tapaihum was the most tolerant among the cultivars studied.

Discussion: In summary, our findings underscore the importance of using SA to mitigate the effects of water restriction on cowpea cultivation. These discoveries are crucial for the sustainability of cowpea production in regions susceptible to drought, which can contribute to food security. We further add that the adoption of new agricultural practices can enhance the resilience and productivity of cowpea as an essential and sustainable food source for vulnerable populations in various parts of the world.

Keywords: Vigna unguiculata (L.) Walp.; antioxidant mechanism; osmoprotection; photosynthesis; production.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. The Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Brazil, finance code 001. To the Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq, for granting financial aid (Proc. 408952/2021-0 and 307559/2022-0) and the Fundação de Apoio à Pesquisa do Estado da Paraíba (Edital Fapesq-PB/CNPq no. 77/2022 and Edital no. 004/2018 – SEIRHMACT/Fapesq-PB).