Effect of Seed Stimulation with the Amino Acid Tryptophan and Yeast on Seed Emergence, Growth, and Sorghum crop

The experiment study of field was conducted in an agricultural field in Anbar Governorate, Ramadi District, throughout the spring period of 2024, for investigation effect of seed stimulation with amino acid (tryptophan) and dried yeast suspension on the distinctness of field and several characteristic of growth and yield of sorghum. Applied the experiment of 2-factor by Randomized Complete Block Design (RCBD) through split-plot system and 3 duplicate, the seed stimulation treatment with the amino acid tryptophan at concentrations of 100 and 200 mg L- considered the major factor Furthermore the control treatment no spraying. The secondary factor was spraying yeast at three concentrations 1500, 2500 and 3500 mg L-1, furthermore the control treatment no spraying. The best results according to the statistical analysis were for tryptophan at a concentration of 200 mg L-1, which showed the fewest days for the flowering period, which amounted to 66.00 days, the highest plant length, the largest leaf size, the chlorophyll index, the number of grains per head, weight for 500 heads, and the individual plant productivity, which amounted to 197.25 cm2, 4615 cm2, 53.33 SPAD, 2018.5 grains per head, 14.66 g, and 58.94 g respectively. Regarding the results of spraying by dry yeast , the concentration of 3500 mg was superior, giving the highest average field emergence percentage (74.11%) and field emergence speed (66.56%). The lowest number of days to reach 75% flowering (67.22 days) was recorded, as were the highest averages for plant height, leaf size, the grains number of per head, the weight of 500-grain , and individual the crop of plant (191.78 cm², 4306 cm², 53 SPAD, 1984.4 grains per head, 14.22 g, and 56.69 g), respectively. This study concludes that stimulating seeds with dry yeast suspension or the amino acid tryptophan, especially at high concentrations, improved in field indicators, growth and sorghum crop , and that this would provide effective treatment for seeds suffering from weak germination.