Dormancy on pigeon pea seeds (Cajanus cajan (L.) Millsp)

An experiment was conducted to study seed dormancy (hardseedness) in seventeen genetic lines and three commercial cultivars of pigeon pea. The seeds were hand-harvested, hand-shelled, and stored in paperbags in a chamber with 10 degrees C and 25 % air relative humidity. Four replications of fifty-seed samples were put to germinate in moist paper rolls at 30 degrees C, after one, two, three, four, five, nine, twelve and fifteen months of storage. No hard seeds were observed among eight lines and the three commercial cultivars. Among these lines, g58-95 had low storage potential, quickly losing germination percentage. Line g184-97 presented low percentage of hard seeds, lines g3-94, g6-95 and a 124-95 kept the initial percentage, g101-97, g127-97, g154-95 and g167-97 had the percentage of hard seeds increased from one to nine months of storage, and percentage of hard seeds of line g27-94, constantly decreased. It was concluded that pigeon pea genotypes vary amply among themselves in terms of hard seed production potential and that satisfactory germination of its seed lots may require artificial chemical or mechanical scarification.