The protective role of Zinc in boron detoxification under the presence or absence of auxin as function of rooting response of mung bean (Vigna ratiata L. Wilczek)


Abstract The role of Zinc in alleviating B-toxicity in terms of adventitious root formation (ARF) in cuttings of mung bean was studied. The toxic level of B in addition, to the promotory conc. of Znsalt was determined. Two of Zn-salts were tested (sulphate, and chloride), auxin was supplied as inductive treatment to enhance rooting response. 1. The toxic level of boron was 150 (µg/ml), this reduced growth parameters in terms of rooting response to 50% compared to control. 2. Zinc sulfate at conc. 1 (ppm) and Zinc chloride at 5 (ppm) developed the highest rooting response in mung bean cuttings. 3. For Boron detoxification, Zn-(sulphate and chloride) were supplied as pre-treatment, posttreatment or simultaneously with toxic-B. The best treatment for boron detoxification occurred completely by supplying Zinc sulphate and chloride prior to toxic-B treatment (pre-treatment), but after supplying auxin inductive treatment. 4. The protective role of Zinc-sulphate and chloride significantly enhanced the average of root number/cutting to its highest level in control treatment.