Longevidade de sementes de mutamba (Guazuma ulmifolia Lam. – Sterculiaceae) no solo em condições naturais

Abstract

The objective of this research was to evaluate the seed viability of mutamba (G. ulmifolia) at different times of burying and depth in the soil in an induced soil seed bank. A randomized block design was used in a 3 x 3 factorial scheme with four plots. The treatments used were three soils depths (0, 2 and 4cm) and three times (3, 4 and 5 months after burying). Each plot had 500 seeds in a bag (10x10cm) buried in nursery soil. The evaluations were seed viability with intact seed, using germination tests, obtaining the number of root emergences, normal seedlings and hard seeds. Further, the number of losses in the soil seed bank were evaluated. The results obtained showed that the mutamba seeds (G. ulmifolia) could stay viable in the soil seed bank after 5 months (25% of total seed buriying showing 72% viability). Seeds on the soil surface and 2cm deep had better average of root emergence and normal seedling percentage than that 4cm deep. The percentage of losses in soil seed bank is 61%, regardless of depth or time.