Níveis de água, matéria orgânica e cobertura morta na produção de mudas de cumaru (Amburana cearensis).

Abstract

The cumaru, Amburana cearensis (Allem.) B.C. Smith, is a native plant of multiple uses, with excellent economic potential, since besides producing wood with exceptional quality, it can be used by the food, perfume and drink industries, being also able to produce active principles for medicines. Considering the lack of management information about this culture an experiment was carried out, on March-August of 2008, in nursery aiming to study the effects of irrigation, organic manuring and mulching on the cumaru seedlings growing. The seedlings growth on 5,95 L pots on which were established 5 different quantities of water, calculated in function of the evapotranspiration rate (0,25 ET, 0,50 ET, 0,75 ET, 1,00 ET and 1,25 ET); 3 levels of organic manuring, as fraction of the total volume of the ground (0,25; 0,50; 0,75); and on presence and absence of mulching. The experimental design adopted was in blocks completely at random, with 4 repetitions. The irrigations were done to each two days. The transplant of the seedlings was carried out to 56 days after the sowing and the irrigation treatments 30 days later. Hundred forty seven days after the seedling it was observed that the plant height was not affected by the levels of water, being influenced positively by the manuring and mulching, still being affected by the interaction water x manure. The steam diameter and the number of leaves were not affected by the treatments however the stem diameter was affected by the interaction of water x manure. The absolute and relative growth rate of the plant height and stem diameter were not by the treatments, only the interaction water, manure and mulching affected the absolute growth rate of the plant height. The irrigation water consumption and the evapotranspiration decreased with the manure doses and in the presence of mulching. The values of the Coefficient of Culture varied with the treatments a with time period. A mean coefficient of 0.39 was obtained for all the treatments and studied periods. Considering that the cumaru is a plant highly adapted to water stress, surviving and growing with very small quantities of water, it must be better studied and utilized on the semi-arid agro-forests.