Fenologia de cultivares de soja em diferentes densidades de plantio como ferramenta auxiliar no manejo da cultura

Abstract

Regionalized studies on the phenology of soybean as well as the duration of each phenological stage based on accumulated thermal sum and water availability is an efficient management tool. The objective of this work was to evaluate the productivity of soybean cultivars at different sowing densities, through the analysis of the development and their interactions with the environment (air temperature, solar radiation, photoperiod and rainfall). The study was developed based on the meteorological data of the National Institute of Meteorology (INMET) automatic station (A-917, OMM86626) and conducted in the crop grown 2017/2018, in the experimental area of the company Agropel Sementes located in the Mid-North region of the state of Mato Grosso, in the municipality of Sinop. The treatments were soybean cultivars with a density of less than 12 plants per linear meter, cultivars of 12.1 to 15 plants per linear meter, cultivars of 15.1 to 18 plants per linear meter and cultivars larger than 18.1 plants per linear meter. meter. A randomized blocks design with four replications was used. The accumulated total thermal sum of the culture was approximately 1200 GDA during the 110 days of cultivation, requiring about 465 GDA to reach the flowering period. Planting density less than 12 plants per linear meter promoted greater node formation in the main stem. The cultivars AS 3810 IPRO, BRS 7380 RR, TMG 1180 RR and DESAFIO RR presented higher yields.