PHYSIOLOGICAL AND ENZYMATIC CHANGES DURING SEED MATURATION AND GERMINATION OF Luehea divaricata

Resumo

Luehea divaricata Mart. is tree is of great ecological and economic importance. This study investigated the effect of fruit maturation on the germination and vigor of L. divaricata. Fruits were harvested at three maturity stages (unripe or green, brown and open) defined by digital colorimetry and seeds extracted from each stage divided into lots of earliest harvested and stored. Germination test was conducted with four replicates of 25 seeds from each fruit maturity stage in plastic boxes under temperature of 30 ± 2 °C. The study was conducted in a 2 x 3 (two lots and three maturity stages) factorial arrangement in a completely randomized design with four replications. Data was submitted to analysis of variance and the means were compared by Tukey at 5%. Germination, germination speed index, average root length and moisture content showed higher values for recently harvested seeds extracted from fruits of all maturity stages compared to stored seeds. LEA protein showed higher activity in seeds from fruits with brown epicarp color of both lots while α-amylase protein activity was higher in the stored seed lot. This shows that better seeds are those that are newly collected fruits and browns.