The effect of vitamins B group and melatonin foliar application on soybean growth indices, leaf senescence and yield components

 Soybean is an important source of oil and protein human and animal protein. The main part of the growth period of this plant is in the summer, which is usually exposed to stresses such as heat, dryness and even salinity, and finally, there would negatively affect the growth and yield of these plants. It can be inferred that it may be possible to use external component to reduce the negative effects of stresses on plants and to increase yield and product quality.Considering the positive anti-tension properties of vitamins in group B and melatonin, it can be concluded that by applying these materials on soybean as a solution of positive effects, the growth and yield of physiological improvement, especially in summer conditions, can be obtained.Therefore, in this research, the effect of these materials on soybean on DPX cultivar, physiological and qualitative aspect was investigated at Shahroud University of Technology Research Field.

Treatments including melatonin foliar application (0, 0.1 and 0.2 mM) and vitamines B group (0, thiamine, riboflavin, niacin, pantothenic acid and pyridoxine 100 mg / L) were organized in factorial experiment on the basis of completely randomized block design in three replications.

The effect of melatonin and vitamin B on leaf area index, stem height, stem diameter, number of seeds per pod, 1000 seed weight, yield, oil yield, and protein content, leaf dry weight, stem dry weight, and reduction of leaf chlorophyll degradation was significant. The most effective on the traits were related to the combination of 0.2 mM Melatonin and Pantothenic Acid.The foliar application of these two substances reduced the chlorophyll degradation process and increased about 2 times the chlorophyll residue compared to the control.There were no significant differences in B vitamins in the two levels of 0 and 0.1 mM melatonin in terms of the effect on this trait and the effect of 0.2 mM melatonin was higher.There was a significant difference between the levels of B vitamins in terms of leaf area index. Pantothenic acid and pyridoxine were more effective than others.The lowest amount of seed oil yield was obtained in non-foliar application treatment with an average of 21 g / m2, which showed a significant difference with all the treatments. The use of B vitamins with a concentration of 0.2 mM of melatonin showed the highest levels of oil yield, the highest amount of which was related to the combination of Pantothenic acid and high concentrations of melatonin with an average of 106 g / m2. Conclusion In general, it can be concluded that the use of melatonin with vitamines B group can induce tolerance to the plant.Therefore, it is possible to use melatonin and vitamin B to increase the growth indices and soybean yield components.