Biofertilizer enhances the expression of the CaWRKY6 gene in water-stressed plants of Capsicum anuum L.

Colombia has agroecological conditions for bell pepper (Capsicum annuum L.) cultivation. However, traditional management practices have depended mainly on agrochemicals. Organic production could enhance the value of products and facilitate their entry into international markets. Research indicates that biofertilizers and biostimulants can activate the gene expression that helps plants tolerate both biotic and abiotic stress. This study assessed the activation of the CaWRKY6 gene in response to water stress tolerance in C. annuum, after applying a biofertilizer to greenhouse-grown young plants to mitigate the impacts of drought. Foliar samples were taken 48 h after the application of five treatments: biofertilizer at two concentrations (5 ml L-1 and 10 ml L-1), salicylic acid (5 mg L-1), and two controls (water), followed by RNA extraction and an RT-qPCR test to determine the relative expression of the gene CaWRKY6. To compare the adjuvant effect of biofertilizer and salicylic acid, treated young plants were exposed to water depletion for 21 d. The ANOVA indicated differences between treatments with 5 ml L-1 and 10 ml L-1 of biofertilizer, and they had the highest CaWRKY6 gene expression, as well as higher growth and less wilting against water stress.