Germination and vigor of Crataeva tapia L. seeds in different temperatures and light regimes

Abstract

The germination behavior of seeds of different species varies on function of the temperature and luminosity, which can provide information of biological and ecological interest, and technology of seeds, because very little is known with respect to the requirements of seeds of tropical species as the various factors involved in germination. Therefore, the work was carried out with the objective of evaluating the effect of different temperatures and light conditions on germination and vigor of Crataeva tapia L. seed. In the Laboratory of Seed Analysis, in the Centro de Ciências Agrárias, Universidade Federal da Paraíba, located in Areia city - PB, were evaluated the influence of temperatures of 25 °C; 30 °C and 35 °C constant and 20-30 °C alternated under white light (without cellophane paper), green (with green cellophane paper), red (with red cellophane paper), far-red (with two sheets red cellophane paper interspersed for two sheets blue) and darkness (with black plastic), adopting a design entirely randomized with treatments distributed on factorial 4 x 5 (temperatures and light regimes), in four replications of 25 seeds each. Characteristics analyzed: germination percentage, germination first count and germination speed index, as well as the length and dry mass of seedlings. The seeds germinated in all light regimes, being recommended that on temperature of 20-30 °C alternate, and on temperature of 30°C. Seeds of species studied are not sensitive to different light regimes applied under different temperatures.