Crescimento inicial de cultivares de soja submetidas a diferentes níveis de estresse hídrico

Abstract

Water deficit is one of the main abiotic factors that limit plant growth and initial development, especially in regions with irregular water availability. In soybean cultivation, water stress in the early stages can compromise seedling establishment, affecting morphological characteristics essential to crop development. Given this context, the present study aimed to evaluate the water stress tolerance of three soybean cultivars by analyzing the initial growth of seedlings subjected to different induced water regimes. The experiment was conducted at the Agricultural Laboratory of the Federal Institute of Piauí (IFPI) – Uruçuí Campus, using a completely randomized experimental design, in a 3 × 4 factorial scheme, with five replications. The cultivars DOMÍNIO BMX 84186 RSF, ADAPTA LTT 8402 IPRO, and OLIMPO BMX 80182 RSF were evaluated under four water regime levels (100, 75, 50, and 25% of the container capacity), according to the methodology proposed by Souza et al. (2000). After 20 days of cultivation in a germinator at 25 °C, with a 12-hour photoperiod, the shoot fresh mass (MFPA), root fresh mass (MFR), shoot dry mass (MSPA), root dry mass (MSR), number of leaves (NF), and seedling height (AP) were evaluated. The data obtained were subjected to statistical analysis using Tukey's test at a 5% probability level, using the R program, version 4.5.2. The results demonstrated that the cultivars showed distinct responses to the applied water regimes, evidencing variations in the initial growth of the seedlings. The cultivars OLIMPO BMX 80182 RSF and ADAPTA LTT 8402 IPRO stood out for presenting better vegetative performance under a full water regime