EFFECT OF 3-INDOLE ACETIC ACID AND GIBBERELLIC ACID ON GROWTH AND YIELD OF ALFALFA BC3 HYBRID

. Alfalfa ( Medicago sativa L.) is a globally important leguminous fodder crop because of its high production and nutritional value. The investigation was conducted to determine an effect of 3-Indole Acetic Acid (IAA) and Gibberellic acid (GA3) on the alfalfa BC 3 hybrid at the breeding room of the institute of grassland science, Yangzhou University, Jiangsu Province, China. Plant height, stem diameter, leaves number per plant, leaf length, leaf width, leaf area, fresh shoot weight, and dry shoot weight were measured. The study used four different IAA and GA3 concentrations (0, 50, 75, and 100 mg L -1 ) with three replications in a completely randomized design. The results revealed that the use of IAA and GA3 was significantly effective in the growth of the alfalfa BC 3 hybrid at the two cutting times. The use of 25 mg L -1 IAA concentration was significantly improved the plant height, leaf width, and leaf area. Exogenous GA3 application significantly enhanced stem diameter, leaf length, leaf area, fresh shoot weight, and dry shoot weight, except for leaf width, which showed a non-significant difference but was higher than that in the control group. Thus, the application of GA3 (i.e., GA3 at 75 mg L -1 ) can be suggested for a higher yield of the alfalfa BC 3 hybrid.