Effects of seed size, maturation and drying on viability of velvet bean seeds - DOI: 10.4025/actasciagron.v29i1.73

Abstract

The aim of this work was to study the effects of seed size and drying way during seed maturation on physiological quality of velvet bean (Mucuna aterrima (Piper et Trace) Holland) seeds. Racemes were harvested weekly, starting 40 days after 50% blooming of the plants (40 DAB) and ending at dry pod stage (89 DAB). The pods of the racemes were divided in two halves considering the position in the axis; half of pods was shelled and the seeds were dried in natural environment conditions of laboratory without air temperature control and relative humidity; the other half was dried as intact pod in same environment conditions and shelled when dry. The dry seeds were sized by sieves with round holes and the percentages of the size-graded by width were calculated. The seeds held on sieves 26/64”, 24/64” and 22/64” (10.32, 9.52 and 8.73 mm, respectively), the predominant sizes, were submitted to germination test. The drying in intact pods resulted in seeds with best physiological quality, independent of maturation stage and seed size. The large seeds coming from dry pods presented less hard seeds percentage.