Influence of temperature and photoperiod on the germination of Senegalia bahiensis seeds

Abstract

Senegalia bahiensis (Fabaceae family, Mimosoideae subfamily) is typical of an anthropic environment, and thus tolerates high levels of disturbance, which supports its use in restoration planting. However, widespread use and marketing of S. bahiensis seeds requires seed quality control, for which there is a dearth of protocols. The aim of the present study was to evaluate the influence of temperature and photoperiod on the germination of Senegalia bahiensis seeds from different matrix trees. Seeds were collected from fruits of 15 matrix trees in the municipality of Castro Alves, Bahia, Brazil. Two assays were performed, one for each parameter tested. The experimental design of both assays was completely randomized in a factorial design, and included three replicates of 25 seeds. The design of the first assay was 15 (matrix trees) × 3 (conditions - 25°C, 30°C and alternating temperatures between 25 and 30°C) and the design of the second assay was 14 (matrix trees) × 3 (conditions - 8 or 12 hours of light, or continuous light). The percentage of germination of normal seedlings, germination speed index, mean root length based on total seed number, shoot length, root length and total length were determined. The Tukey's test was used to compare mean values. The S. bahiensis matrix trees used in this study have different requirements in terms of temperature and photoperiod for seed germination. According to our findings, combining a temperature of 30°C and an 8 h period of light conveys the most suitable conditions to conduct germination tests for most matrix trees.