Eliciação em plantas de feijoeiro buscando mitigar os efeitos da deficiência hídrica

Abstract

The common bean plant is one of the main cultivated species in Brazil, with morphological traits that enable its adaptation to different environmental conditions. Therefore, a study aiming to minimize the impacts of water deficiency (WD) on common bean yields was required. The study aimed to evaluate the elicitors: acibenzolar-s-methyl (ASM) and the product derived from seaweed (PDS) utilization as resistance inducers in two common bean cultivars (Phaseolus vulgaris L.), IAC-Imperador and IAC - Milênio, under water deficit conditions. Elicitors were applied after the emergence of the first fully expanded leaves (compound leaf) - V3 stage. The second application occurred at the R6 stage. The experiment was carried out from January to June of 2020 in a greenhouse of UTFPR, Pato Branco campus. The yield components were evaluated with and without elicitors application and with and without water deficit. It is known that water absence causes yield losses, changing the plant metabolism. Therefore, activities from the enzymes Superoxide dismutase (SOD), Peroxidase (POX), Catalase (CAT), and proline amino acid (POD) were measured. Results evidenced that application of the elicitors ASM and PDS in V3 intensified the activity of antioxidant enzymes of the plants, which are related to the plant defense mechanism - CAT and POX in the cultivar IAC Imperador; CAT and SOD in the cultivar IAC Milênio - suggesting a response to the application of elicitors, which mitigated oxidative damages provided from ROS. Under water deficit conditions, the application of elicitors in R6 increased proline concentration and POX activity in the IAC Milênio. In the IAC Imperador, proline concentration and SOD activity increased under water deficit conditions. ASM treatment resulted in a lower yield. The water deficit and the use of elicitors did not influence the water potential. However, the ASM and PDS elicitors showed promise in water deficit tolerance in the common bean crop. More studies should be carried out, including under field conditions.