T
he study aimed to determine the efficacy of harvest dates and storage periods under various plant biostimulants. A way to reach the best storage periods for “Shandawil 3" for expanding sesame cultivation in newly reclaimed lands. Results revealed that Spirulina with chlorella achieved a significant increase in most of the studied traits such as the plant height, number of branches/plant, number of leaves/plant, first capsule height, number of capsules/plant, biological yield, seed yield, standard germination, seedling length, electrical conductivity, thousand seed weight, protein content, seed oil of sesame seeds, peroxidase value and acidity number followed by chlorella alone, spirulina and vinasse alone. For the harvest date, the optimum date (120 days) achieved significant values for most of the studied traits compared to harvesting before the optimum date. Storage periods of 0, 6, and 18 months, respectively recorded the highest values for germination and seed quality. In comparison to other periods, 18 months of storage produced the lowest values for germination percentage, seedling length, seedling dry weight, and vigour index. Respecting the interaction effects between biostimulants, and harvest dates, spirulina+ chlorella achieved the highest plant, highest No. branches/p, while, chlorella 2% alone recorded the highest number of leaves/plant. Spirulina 2% recorded the highest values of highest of first capsules. Using Spirulina with chlorella at the optimum harvesting date gave the highest values of a number of capsules/p, seed yield, and biological yield compared with other treats. Seedling parameters are no appreciable variations among stimulants, harvesting dates, and storage periods.