Rapeseed population arrangement defined by adaptability and stability parameters

The objective of this study was to identify the plant arrangement that allows greater grain yield with adaptability and stability of rapeseed hybrids. The experiments were conducted in randomized block design with four replicates and the 12 treatments consisted of combination of inter-row spacings (0.20, 0.40, and 0.60 m) and plant densities (20, 40, 60 and 80 plants m-2). The hybrids Hyola 432 (early cycle) and Hyola 61 (medium cycle) were cultivated in three growing seasons (2008, 2009 and 2010). Grain yield was evaluated based on the parameters adaptability and stability according to the models of Wricke and Eberhart & Russell. The plant arrangement for obtaining higher grain yield depends on the cultivated genotype. Higher grain yield was obtained in the arrangements of 0.20 m x 60 and 0.40 m x 60 plants m-2 for Hyola 432, and in 0.20 m x 60 plants m-2 for Hyola 61, in the three years of evaluation. In the inter-row spacing of 0.40 m and densities of 40 and 60 plants m-2, Hyola 432 shows high yield, adaptability to wide environments and stability. For Hyola 61, high productivity with overall adaptability was obtained in the inter-row spacing of 0.40 m, with 60 plants m-2.