Intensity and duration of water deficit on the pathosystem sugarcane x Meloidogyne incognita

Abstract

ABSTRACT This study aimed to evaluate the interaction between intensity and duration of water deficit (90, 56 and 22% of pot capacity [PC] for 30, 60 and 90 days under continuous stress) associated to the parasitism of the nematode Meloidogyne incognita on the growth of the sugarcane variety RB92579 and the activity of the enzymes catalase and ascorbate peroxidase. The experiment was conducted in completely randomized design in a 7 x 2 factorial scheme (seven water deficit treatments: control [90% PC], 56% PC for 30, 60 and 90 days, 20% PC for 30, 60 and 90 days; and two densities of M. incognita: 0 and 20000 eggs plant-1), with four replicates. The water stress corresponding to 56% PC for 30 or 60 days did not affect RB92579 development. The evaluated water treatments increased ascorbate peroxidase activity, but it did not affect catalase activity. Nematode inoculation did not affect RB92579 responses to drought stress conditions. The higher severity of water deficit (22% PC for 90 days) reduced M. incognita reproduction.