Seed filling and fatty acid changes in developing seeds of castor bean (Ricinus communis L.)

摘要

A detailed knowledge of storage reserve accumulation in developing seeds can provide vital information to create strategies for improving the lipid content as well as the natural value of castor (Ricinus communis L.) crop. After hand pollination (female flowers-tagged), seed filling (lipid and protein accumulation) in castor bean is initiated as early as 7 days after pollination (DAP). Accumulation of proteins (0.129–0.152 mg/seed) and lipids (0.01–0.051 mg/seed) in developing castor bean seeds increased rapidly up to 35 DAP, followed by a decline in both the storage reserve accumulations at the maturation stage of 63 DAP. Nile red (10 g/ml dissolved in glycerol) fluorescence imaging technique was used to visualize the oil body synthesis (seed sections) from 7 to 63 DAP. Significant variations (P< 0.05) in fatty acid compositions were observed concurrent with the lipid accumulation pattern at different developmental stages. The unsaturated fatty acids (UFAs) content comprised 97.5% of the total fatty acids composition. Ricinoleic acid content was the predominant fatty acid component (over 85%) with other fatty acids such as palmitic, stearic, oleic, linoleic, and linolenic present in minimal amounts. Current findings entrust vital information on endogenous protein and lipid deposition in this potential oil crop in an innovative approach for physiological modifications in its oil seed.