Arranjo espacial de plantas e adubação com NPK no desenvolvimento agronômico de soja

Abstract

The annual tillage of soybean (Glycine max (L.) Merrill) and maize (Zea mays L.) are among the most economic relevance of Brazilian agriculture, being produced in the harvest of 2013/2014, about 132 million tonnes of these grains. The objective of this study was to evaluate, for two harvests, the agronomic characteristics of indeterminate growth of soybean and corn hybrids in different row spacings (0.35, 0.40, 0.50, 0.60 and 0.70 m for soybean) and (0.45; 0.50; 0.60; 0.70; 0.90 m for corn) and four fertilizer levels (0, 200, 400 and 600 kg ha-1) with NPK 02-20-18 for soybean and NPK 16-16-16 for corn. We used the experimental randomized block design and the treatments were arranged in split plots being allocated in the splits NPK fertilizer levels and the subplots the row spacings with three replications. For the two cultures, the variables analyzed were more influenced by crop and by spacing than the fertilizer levels (NPK) or by the interaction between the factors studied. For soybean crop smaller spacing propitiated smaller final stand of culture, smaller plant height, the greater number of branches per plant, increased number of pods and seeds per pod, shorter time for closing canopy and increased productivity. Higher levels of NPK fertilizer showed higher number of seeds per pod and lower time for closing the lines. For corn, 0.45 m spacing showed lower final stand and time to closing the canopy and a larger number of rows per ear, the greater number of kernels per row, stem diameter, productivity. Is recommended in succession soybean-corn in Ponta Porã-MS, the use of row spacing of 0.35 m, associated with the dose of 600 kg ha-1 NPK (02-20-18) for the cultivation of the variety soybean (Glycine max (L.) Merrill) BMX Power RR and the row spacing of 0.45 m for the cultivation of maize (Zea mays L.), hybrid Pioneer 3431 HX.