Polímero hidroretentor na mitigação do déficit hídrico em mudas de goiabeira.

Abstract

The guava tree has significant socioeconomic importance in the Northeastern semi-arid region of Brazil; however, its production is still limited due to the low water availability in this region. Therefore, irrigation management strategies combined with the use of hydroretentor polymers can ensure better crop production, as this technology helps retain moisture in the soil for a longer period. In this context, the objective was to evaluate the effect of the hydroretentor polymer on the morphophysiological aspects of guava trees subjected to irrigation management with different irrigation intervals. The experiment was conducted in a greenhouse at the Center for Agrofood Science and Technology of the Federal University of Campina Grande, Pombal, PB. The experimental design used was randomized blocks in a 5 × 4 factorial scheme, involving five irrigation intervals (1, 2, 3, 4, and 5 days after each irrigation event) and four doses of hydroretentor polymers (0, 2, 4, and 6 g dm-3) with three replicates and two plants per plot, totaling 120 experimental units. Irrigation management with a 5-day interval proved to be effective when combined with a hydrogel dose of 2 g dm-3 due to the increased chlorophyll b content. There was a greater accumulation of chlorophyll a content in the Paluma guava tree when the estimated dose of 6 g dm-3 of hydrogel was used, regardless of the irrigation interval. The dose of 6 g dm-3 of hydrogel intensified the negative effects of water deficit caused by the 5-day irrigation interval on the growth and phytomass of the cv. Paluma guava.