Secagem de feijão (Phaseolus vulgaris L.) em camadas finas, a baixas temperaturas e seus efeitos na germinação das sementes.

Abstract

The work was effected at the Physical and Mechanical Properties of wood Laboratory, of the Foresty Engineering Depar tament at the Storage Laboratory of the Agricultural Engineering Departament, and the Seeds Laboratory of the Plant Science Depar tament, of the Center of Agronomic Sciences of the Federal UnZ versitu of Viçosa, Viçosa, Minas Gerais, whit the objective of establishing the curves for bean drying, in thin layers, with the drying air at temperatures of 30°C, 35°C, 40°C, 45°C and 50° C, and 40% and 50% of relative humidity, with constant speed in order to verify the effects of these conditions in the germinati on of bean. For drying, an experimental drier was used, specially designed for the purpose, and to observe the drying offects on the germination, the standard germination test was applied to the beans, after drying. The results relative to drying were submited to regres sion analysis to test the adjustment to Page and Thompson's Mo dels to the drying conditions utilized in this experiment. In the standard test of germination, in order to deter mine the germination percentual, a totelly casualized design was used for the average comparison and the t test in the comparison of the highest average of the germination percentual of seeds submitted to the drying process, with the average percentual of seed germination, at its initial condition. This experiment indicated that the humidity of seed be_ ans decreases eoqponentially with time under the conditions emplo^ yed for the drying air, arid that an exponential function similar to Page's Model is adequate to describe the bean drying under the same conditions. It was further verified that the drying process affects the beand seeds germination; germination diminishe when higher temperatures of the drying air are used, within the temperatures used in this experiment.