Crescimento inicial de mudas de pau ferro (Caesalpinia ferreaMart. ex Tul. var. leiostachya Benth.) sob diferentes regimes hídricos

Abstract

The objective of this study was to evaluate the initial growth of Caesapinia ferrea Mart ex. Tul var. leiostachva Benth (Fabaceae-Caesalpinioideae) under four hidric regimes (overflow, 70, 40 and 12.5% of field capacity). The seedlings were submitted to the treatments after 60 days of age. The experimental delineation was completely randomized with four repetitions of eight seedlings for treatment. After 7 days of permanence under treatment, the evaluations had been initiated. The diameter (6,5 mm), relative water content (52.45%), specific foliar area (174.58 g cm2), rate of relative growth (0.0160 g g-1), liquid assimilated rate (0.0004 g dm-2 days-1) and specific weight of leaf (0.0062 g cm2) did not vary statistically between the treatments. The seeds under 70% CC had presented greater height (84.6 cm), size of the root (28.9 cm), dry mass of the root (6.24 g), foliar area (376.0 cm2), dry mass of the leaf (1.98 g), dry mass of the aerial part (8.27 g) and content chlorofile (31.67 ìg cm2).The ratio of specific weight (0.2368 g g-1) and the nitrogen content (0.37 g kg-1) was higher under 12.5% CC. The ratio of foliar area (35.09 g g-1) was lower under 12.5% CC. Therefore, the best condition for the production of the seedlings is at 70% of the field capacity.