Cultivo de morango em substrato sob concentrações de hidrogel

Abstract

Strawberry cultivation occurs in almost all regions of the world. However, despite the high agricultural potential, cultivation in Brazil presents obstacles, mainly in the Northeast region. The Northeast region of Brazil has high air temperatures that delay development and decrease strawberry production. As an alternative, the use of day-neutral cultivars becomes a viable strategy for cultivation in the region. Associated with the use of the photoperiodic cultivar, cultivation in a protected environment and the use of hydrogel in the substrate can contribute to reducing air and leaf temperature variations and increasing efficiency and water use. Given the above, the objective was to evaluate the morphophysiological responses, thermal index, agronomic performance and productivity of strawberry cultivars grown under hydrogel concentrations in the substrate. The experiment was carried out from June to October 2022 in a protected environment, belonging to the company Estufa Timbaúba, located in the municipality of Guaraciaba do Norte, Ceará, Brazil. The work was divided into 2 chapters corresponding to the stages of strawberry development. The design used was randomized blocks arranged in a 5 x 2 factorial scheme, referring to five concentrations of hydrogel (0.0; 1.0; 2.0; 3.0 and 4.0 g L-1 of substrate) and two strawberry cultivars (Albion and San Andreas), with four replications and each experimental unit was composed of 26 plants. In chapter 1, evaluations of the number of leaves, crown diameter and crown height at 30 and 60 days after transplanting (DAT) were carried out. Stomatal conductance, transpiration, CO2 assimilation rate, internal CO2 concentration, intrinsic water use efficiency, instantaneous carboxylation efficiency, instantaneous water use efficiency and the thermal index were evaluated at 60 DAT in the morning and afternoon. In chapter 2, gas exchanges and physiological indices at 90 DAT were evaluated in only one period; plus the number of fruits per plant, average diameter, average length, average fruit mass and yield. The hydrogel reduced the thermal index of strawberry cultivars grown in substrate, consequently, enabled an increase in plant growth and development 60 days after transplanting (DAT). Increasing hydrogel concentrations in the substrate caused deleterious effects on gas exchange at 90 DAT, regardless of cultivars. The agronomic performance and productivity of strawberry cultivars did not show significant differences for the evaluated period.