Abstract
•Seedless okra production: Flower bud, flower ovary and shoot xylem injection method were used. Still nobody used this innovative techniques in the world in okra seedless.•Microsyrnge injection: This technology was applied on the flower bud, ovary and shoot xylem which was an innovative technique rather than spray as common and traditional method.•Flower bud and Ovary injection: Innovative techniques were applied.
The study was conducted to evaluate the effect of different concentrations of indole 3-acetic acid (IAA) on the okra growth and seedless production. The micro syringe injection technology applied on the flower bud, ovary and shoot xylem was an innovative technique of growth regulator application (IAA) and used in this experiment rather than spray as common and traditional method. Flower bud injection technique was applied on the flower before flowering (Expt. 1), flower ovary injection technique was applied on the flower after anthesis of flower (Expt. 2) and shoot xylem injection technique was applied on the main shoot (stem) before flowering (vegetative stage) using IAA at 0, 25, 50, 100 and 200 mg/L concentrations (Expt. 3). The concentrations of 25, 50 and 100 mg/L IAA greatly exhibited higher pod setting percent compared with the 0 and 200 mg/L in the case of flower bud, ovary and shoot xylem injection. The higher pod length, diameter, weight, size, total soluble solids and vitamin C, chlorophyll and Photosynthetic yield (Fv/Fm) was found in 50 and 100 mg/L compared with 0, 25 and 200 mg/L concentrations in the case of all experiments. The highest (100 %) seedless was observed at 100 and 200 mg/L concentration in ovary and flower bud injection. The relationship between IAA concentrations (mg/L) and seedless percentage per pod was R√ = 0.905. It was found that concentrations of IAA 50 and 100 mg/L) increased potassium (K), calcium (Ca), magnesium (Mg), sodium (Na) and iron (Fe) content compared to the control (0) and 200 mg/L concentration in the case of all experiments. The result seemed that IAA 100 and 200 mg/L concentrations were the effective for seedless okra production in flower bud and ovary injection technique which was an innovation for okra.