Four field experiments were carried out in Lavras (south region of Minas Gerais State) during three seeding seasons whit the purpose of studying the agronomical performance of common beans cultivars from different commercial groups by using both the conventional and no-tillage systems on different soil coats. The treatments were arranged in a split block schema. A randomized block design was used with four replications. In the first three experiments, six cultivars (Ouro Negro, Talismã, Carioca, Pérola, Roxão and Jalo ESAL) and four planting systems (conventional and no-tillage on oat, wheat and bare soil straw) were used in the treatments. The same statistical design and the same cultivars were used in the fourth experiment. However, only three planting systems (conventional and no-tillage on oat and bare soil straws) were used. The amount of straw used in no-tillage system, as well as the beans plants and the grain yield, was estimated. The beans cultivars agronomical performances were modified by the planting system, especially by the seeding seasons. In general, the black-grain Ouro Negro cultivar has performed better than the carioca-grain ones (Talismã, Carioca, and Pérola). The cultivars with the biggest grains were those that have had the worst performance. The highest grain yields were achieved in the winter-spring irrigated season, followed by the rain season, and finally the dry season. At more favorable environmental conditions the no-tillage system was found to surpass the conventional one. The no-tillage on bare soil straw promotes better grain yield at less favorable environmental conditions.
Phaseolus vulgaris; oat; wheat; no-tillage; bare soil straw
