Resposta da soja e do eucalipto ao aumento da densidade do solo e a doses de fósforo

Abstract

Agriculture and soil management in the Cerrado can cause soil compaction, resulting in decreased porosity and water and nutrient availability, with a negative impact on plant growth and development. The objective of this study was to evaluate the effect of soil density and phosphorus doses (P) on soybean and eucalyptus grown in two Cerrado oxisols with different texture: one (LV) with 610 g kg-1 clay and the other (LVA), with 190 g kg-1 clay. Three soil densities (0. 90, 1. 10 and 1. 30 Mg m-3) and five P doses (0, 100, 200, 400, and 800 mg dm-3) were used for LV; for LVA, soil densities were 1. 30, 1. 50 and 1. 70 kg dm-3 and P doses 0, 75, 150, 300, and 600 mg dm-3. Soybean plants were harvested 40 and eucalyptus plants 80 days after sowing. The dry matter and P content were evaluated in shoots and roots of both species. Plant height of eucalyptus was also evaluated. The results showed that: (a) increasing soil density decreased the growth of both species, particularly in LV; (b) plant response to P decreased with increasing soil density; (c) eucalyptus was more affected by increased soil density but absorbed the applied P more efficiently than soybean. In general, the negative effect of increased soil density on plant dry matter, for both species, at the lowest P doses, was compensated when the highest P doses were applied.