Produtividade da soja após aplicação superficial de doses de calcário na borda sul da Amazônia

Abstract

The base saturation method has presented some limitations in the limestone recommendations for no-tillage system. Some authors attribute this to the reduced contact surface between limestone particles and soil in this system, so it is necessary to recalibrate or create a factor that improves the method, so that it presents greater accuracy. The objective of this work was to test high doses of different types of limestone (calcitic and dolomitic) and to evaluate soybean yield variables. The experiment was conducted in the field, Sinop - MT, in a sandy loam soil in the 0-20cm layer, with T: 5.9 cmolc.dm-3, V%: 54.4%, pH in CaCl2: 5, 3 and MO: 1.9 dag.kg-1. The plots were 10x8m using a randomized block design, 4 blocks and 11 treatments, ranging from 0 (control) to 7.39 t / ha of limestone. It was used to cultivate Bmx Bonus. The following yield variables were evaluated: plant height, grain per pod, pod per plant, one thousand seed weight, and yield. There was no difference between treatments in the analyzed variables. This can be attributed to the fact that the soil used already has built fertility and the short period between the application of limestone and the stage of greatest nutrient need of the cultivar, of undetermined growth, in which the reaction of limestone cannot be completed.