Germinação e vigor de sementes e desenvolvimento pós-seminal de Crotalaria Spectabilis Roth

Abstract

Crotalaria spectabilis Roth is a species which has been standing out in the improvement of the quality of ground and control of nematodes in some states of northeast. The objective of this work was to get given biometrics data of seeds (length, width, thickness and weight of 1000 seeds), to study the sprouting behavior in terms of the substratum, temperature and light, being considered the botanical and technological criteria of germination, to follow and to register the after-seminal development, as well as comparing different tests of vigor. For physiological potential evaluation, the seeds had been divided in five lots, being submitted to the tests: germination, first counting, electric conductivity and traditional accelerated aging. After this stage, different concentrations of 2, 3, 5 triphenil tetrazolium chloride salt had been studied in order to establish colorimetric standards in seeds with different levels of vigor obtained by the test of accelerated aging. The seeds present length, width and thickness of 4,4 mm; 3,3 mm and 1,6 mm, respectively, with the total of 62.189 seeds in one kilogram. The temperatures of 25 and 300C, using the paper substratum, in the light presence, had provided the best values of percentage and germination speed of the seeds in relation to the botanical criterion, whereas for the technological criterion, the temperature of 250C was statistically superior for these two variables in the same described conditions. The germination of the seeds of Crotalaria spectabilis is epigaea and plantules is phanerocotyledonarious. The studied tests had not exposed differences of vigor in the five studied lots, with exception of the one carried through electric conductivity with 50 ml of water. The tetrazolium test revealed promising in the identification of seeds with different levels of vigor.