Quitosana na indução de tolerância ao déficit hídrico em híbridos de milho

Abstract

Among the limiting factors of plant production, the water deficit occupies a prominent position. This environmental stress interferes with the development of crops, causing physiological disturbances that impair the growth and agronomic yield of the vegetables. In this situation, it is necessary to know more about alternative ways that allow com plant to tolerance water deficit. Chitosan, considered a biostimulant, can stimulate physiological responses, acting as a antiperspirant in agricultural stress situations. Therefore, the present research sought to elucidate the feasibility of the use of this biopolymer in the induction of the tolerance to water deficit. The results obtained in greenhouse, regard to the most efficient chitosan dose (140 mg/L), were repeated under field conditions. For this, biochemical evaluations were performed by the quantification of antioxidant enzymes activity, SOD, CAT, APX and PAL, as well as ecophysiological characteristics, such as gas exchange, relative chlorophyll content, photosystem I and II and characteristics related to production. The results obtained in the present study provide evidences about the potential use of chitosan to increase the tolerance to water stress.