EFFECT OF SOAKING SORGHUM SEEDS WITH BARASSINOLID FIELD EMERGENCE AND VEGETATIVE GROWTH CHARACTERS

The field experiment was conducted in the field belonging to the College of Agriculture in the Al-Buaitha region in the city of Ramadi during the fall season of 2021. The aim was to stimulate seeds with the growth regulator Brassinolide and investigate its role in the vitality and activity of seedlings and the field establishment of varieties of sorghum to determine the best stimulation treatment for the best variety. The randomized complete block design (RCBD) was used in the field experiment with three replications for two factors. The first factor was seed soaking treatment for 12 hours in a distilled water solution with the growth regulator Brassinolide at concentrations of 200, 400, and 600 mg L-1, in addition to the control treatment (soaking with distilled water only). The second factor was three varieties of maize: White (Save, Rabeh, and Lilo). The results of the field experiment showed that the treatment of seed stimulation with the growth regulator Brassinolide at a concentration of 600 mg L-1 significantly increased most of the studied traits. It recorded the highest averages for emergence speed (75.44%), percentage of emergence (90.00%), plant height (165.14 cm), chlorophyll content (62.09 spad), and leaf area (610.49 cm2). For the characteristic of the number of days from planting to 75% flowering, the same concentration resulted in the lowest number of days, amounting to 61.11 days, compared to the control treatment (soaking with distilled water only). The cultivars differed significantly among themselves. The White cultivar was distinguished in some traits, giving the highest average for field emergence speed (69.58%), percentage of emergence (86.58%), plant height (161.96 cm), and chlorophyll content (57.80 spad). The same cultivar was also notable for the number of days from cultivation to 75% flowering, recording the least number of days (63.00 days). For the leaf area characteristic, the Lilo cultivar was distinguished, giving the highest average of 600.85 cm2. The results showed a significant effect of the interaction between the two study factors on most of the studied traits. In conclusion, the results of this study indicate that stimulating the seeds with the growth regulator Brassinolide generally led to an increase and improvement in all studied traits. This will positively reflect on the grain yield by enhancing its components.