Maternal light environment during seed development can affect seed quality of Euterpe edulis

Abstract

The primary concern of this research was to investigate how the contrasting light environments of a native forest (NF) and banana intercrop (BI) affect seed quality of Euterpe edulis. The results from our study also led us to investigate a possible light-induced component of seed dormancy in this species. Mature fruit bunches were collected from both environments and evaluated for seed germination and viability of non-germinated seeds, seed mass, water content and vigor tests (germination rate index and seedling mass). Total phenolics in seed coats and the effects of seed coat extracts on germination of lettuce seeds were also evaluated to investigate a possible cause for the lack of germination of many viable seeds from BI. Results showed that seed vigor did not differ between the environments, but germination of seeds from BI was lower, despite viability of most of the non-germinated ones. Seed coats formed in BI had a greater concentration of phenolics than those that developed in NF. In contrast to seed coat extracts from NF, extracts prepared from BI seeds had a negative, non-osmotic effect on the germination of lettuce seeds. Our results indicate that the more open environment provided by BI does not affect seed vigor, but may add a light-induced component to seed dormancy of the species, which can make seeds produced in more open environments less suitable to generate new plants. Such finding might be particularly useful for the species management in agroforestry systems and for its conservation in the rainforest.