Physiological and proteomic insights related to the loss of seed viability in Cariniana legalis (Lecythidaceae)

摘要

In seed conservation, proper storage conditions are crucial to prolonging viability, especially for seeds of endangered woody species, such as Cariniana legalis. We evaluated the influence of the storage temperature and time on the viability of C. legalis seeds and performed physiological and proteomic analyses. Seeds were stored at 6 and 25 degrees C for 24 months. At 4-month intervals, the germination (%), seedling growth, moisture content and electrical conductivity were evaluated. The proteomic profile was evaluated in seeds before and after 8 months of storage. The viability of the seeds was maintained for a longer time at 6 degrees C than at 25 degrees C. At 25 degrees C, seeds showed no germination at 8 months, which apparently was related to a higher seed moisture content and changes in accumulation of the proteins alcohol dehydrogenase, proteasome subunit alpha type and triosephosphate isomerase. Moreover, the absence of the aconitate hydratase 3 protein in seeds at 8 months of storage at both temperatures was related to the reduction of seed viability when stored at 6 degrees C and lack of germination of seeds stored at 25 degrees C, which can be associated with reduced mobilization of seed-stored reserves. In addition, the time spent in seed storage at both temperatures induced a reduction in the abundance of phosphoglycerate kinase and heat shock proteins, both which might be required for better seed longevity. Our results show that germination is negatively affected by the temperature and time of storage, which both affect the protein profile of C. legalis, an endangered species from the Brazilian Atlantic rainforest.