Arranjos espaciais na cultura da soja submetida a doses de fósforo e potássio

Abstract

The soybeans have been broadly cultivated in Brazil and the world due to it`s food and economic importance, that boost many agroindustrial complexes. The objective of this study was evaluate the effect of spatial arrangements, simple and twin rows, associated with different fertilizing levels on the development and yield at Anta 82 RR soybean cultivar. The experiment was carried in Universidade Federal de Goiás, Regional Jataí, with 10 treatments established in a split plot randomized block design, with four replications. Each plot corresponded to one fertilizing level with P and K (0, 50, 100, 200 and 400% of recommended dose) and the sub plots were two spatial arrangements: simple (0,45 m) and twin rows ( 0,25 x 0,65 m). The recommended rate of P and K was 80 kg ha-1 of P2O5 and 80 kg ha-1 of K2O. During the development period of the culture were determined the initial population, Falker chlorophyll index, dry mass, leaf area index, cover factor and nutritional content of the index leaves. When the soybean plants was in growth stage R8 were done the following evaluations: final plant population, plant and first pod insertion height, number of pods and grains per plant, number of grains per pod, mass of thousand grains and yield. The soybean cultivar Anta 82 RR demonstrated small answer for morphological components, with the use alternative spatial arrangements. The increase of fertilizing level, even with rates 2 and 4 times higher than the recommended, allowed soybean response in grain yield for the two studied arrangements. The simple arrangement provides higher grain yield, independently of fertilizing level.