Soybean morphological and productive characteristics influenced by meteorological parameters and sowing dates

Abstract

The aim of this study was to evaluate the influence of meteorological elements on soybean morphological and productive characteristics in five sowing dates. The randomized block design was used in a 5x5 factorial, with the following five sowing dates during the year 2013: the first (10-15), second (10-30), third (11-15), fourth (30-11) and fifth (12-15, 2013), and the following five soybean cultivars: BMX Alvo RR, BMX Veloz RR, CCGL Tec 5721 IPRO, BMX Tornado RR and CCGL Tec 7849 IPRO, with three repetitions. Total dry biomass, leaf area index, plant height, number of pods per plant, number of grains per plant, 1000-grain weight and yield were assessed. According to analysis of variance, significant difference was found for all variables in the cultivar x sowing date interaction. Soybean cultivars morphological and productive characteristics were influenced by meteorological elements and sowing dates. Leaf area index and total dry biomass had the highest means in 11-15 and 11-30, coinciding with the highest grain yield means, obtained for Veloz and Tornado cultivars, respectively. These results were obtained because these sowing dates had the best conditions, with air temperatures between 13.4 and 34.2 °C, accumulated solar radiation of 3074.009 MJ m^-2, accumulated thermal time of 1959.15 °C days and total rainfall of 732.8 mm.

Additional keywords: Glycine max L.; leaf area index; solar radiation; thermal time; yield.