Hexaconazole foliar application alleviates water deficit effects in common bean

Abstract

Currently, the world is facing many problems of crop production. Among them, water deficit is the most dangerous one. This study aimed at evaluating the possibility of enhancing the water deficit tolerance of common bean plants, during two growth stages, by the exogenous application of hexaconazole. The experimental design was completely randomized, in a factorial arrangement, with three replicates. Hexaconazole (0 mg L^-l, 10 mg L^-l and 20 mg L^-l) was sprayed at flowering (R3), at 60 days after sowing, and at the grain-filling stage (R8), at 90 days after sowing. After the application, the plants were subjected to water deficit by withholding irrigation for seven days. Although all hexaconazole concentrations improved the water deficit tolerance in bean plants, in terms of plant growth and yield, the application of 20 mg L^-l provided a better protection, when compared to the other concentrations (p < 0.01). The exogenous application of hexaconazole improved the water deficit tolerance, if compared to non-treated plants, affecting the morphological characteristics, yield components, total chlorophyll, proline, relative water content and enzymatic antioxidants (p < 0.01). The results showed that the hexaconazole-induced tolerance to water deficit in common bean is related to changes in the growth variables and antioxidants. In conclusion, the hexaconazole application could improve the bean growth and yield under water deficit conditions.