Desenvolvimento de cultivares de soja em função do grupo de maturação e tipo de crescimento em terras altas e terras baixas

Abstract

The objective of this study was to characterize the development of soybean cultivars with different maturity group, and growth types grown in highlands and in lowlands in Rio Grande do Sul. Field experiments were conducted in Santa Maria (highland) and Capão do Leão (lowland) during the 2010/2011, 2011/2012 and 2012/2013 growing seasons, with 11 treatments (soybean cultivars). Nine sowing dates were conducted in Santa Maria and one in Capão do Leão. The experimental design in all experiments was a randomized block design with split plots. The duration of the development cycle, vegetative and reproductive phases, and the period between the date that was the final number of nodes and early flowering was measured in °C day, for all sites and sowing dates. There was reduction in the duration of the reproductive phase, total development cycle (except some cultivars sown in september), with delay on sowing date regardless of the maturity group and type of growth with delayed sowing. Sowings of September, January and February promote a reduction in vegetative stage in most cultivars when compared with the recommended period (November and December). Cultivars Indeterminate have a longer period of overlap between the vegetative and reproductive phases than certain cultivars in all sites and sowing dates. The soybean development is similar when grown in highlands and lowlands.