Índices fisiológicos de soja hortaliça em duas épocas de semeadura no Recôncavo Sul Baiano

Abstract

The objective of the present work was to evaluate the performance of four vegetable soybean genotypes and one vegetable soybean cultivar in two sowing periods (April / 2009 and August / 2009) under South Reconcavo Baiano Region environmental conditions. The experiments were installed in the field at the Federal University in the county of Cruz das Almas – BA. The experimental design was in random blocks, with five treatments (genotypes: JLM 17, JLM 18, JLM 19, BR 94 and the BRS 155 cultivar) and five replicates. The experimental plots were made up by eight rows of 5.0 m in length: spacing of 50 cm between rows and 12 seeds per meter, with three side borders, three for yield data and two for growth analysis. Samplings of five plants per plot taken at random were carried out every fifteen days from 21 days after emergence (DAE) until physiological plant maturity in order to quantify dry matter mass (g plant -1 ) and plant leaf area (dm²). These characteristics were used to determine the following physiological indices: crop growth rate (CGR), relative growth rate (RGR), net assimilatory rate (NAR) and leaf area ratio (LAR). NAR and LAR were the most efficient physiological indices to indicate the performance and growth of the materials evaluated. However, vegetative and yield performance of the plant should be measured by the combined response of the physiological indices since they are interconnected, leading to compensation effects between them.