Compactação do solo e manejo da água. I: efeitos sobre a absorção de N, P, K, massa seca de raízes e parte aérea de plantas de arroz

Abstract

The present work had as objective to evaluate the effects six compaction levels, associated with different water managements upon uptake of nitrogen (N), phosphorus (P) and potassium (K), the development of root and shoot of rice plants. The experiment was conducted during the period of September 2002 to January 2003 in a greenhouse at UFLA university, in Lavras- MG. Six compaction levels were tested: 0%, 16%, 32%, 48%, 64% and 80% in a range of variation of soil density (0.25 kg dm-3), combined with three soil water contents: saturated soil, irrigated when were consumed from 25% to 30% and from 50% to 60% of available water, respectively. The management with the greatest soil water availability favored the average of P and K contents in the shoot of the plants, root dry matter yield, number of tillers per pot and dry matter of the shoot of rice plant, regardless of soil compaction levels. On the other hand, soil compaction decreased the averages of all the characteristics evaluated, regardless water management. Nevertheless, water management had the most limiting effect on the uptake of nutrients and shoot dry matter of the plants than soil compaction.