Effect of Indole-3-butyric acid (IBA) Concentration on Approach Grafting Macadamia (Macadamia integrifolia cv. MAUKA, HAES 741)

Abstract

     Effect of Indole-3-butyric acid (IBA) Concentration on approach grafting Macadamia tree was carried out at the Chiangmai Royal Agricultural Research Center (CMRARC), Maehea and Kunwang substation in 2015-2018. The study divided into 3 experiments 1) Study of IBA concentrations on approach grafting Macadamia in May. 2) Study of IBA concentrations on approach grafting Macadamia in July. 3) Study of IBA concentrations on approach grafting Macadamia in November. There are 5 treatments as water (control) and sprayed with IBA concentration of 2000, 4000, 6000 and 8000 ppm. There were 8 replication (20 plants/replication). The results showed that the highest root weight were found in May at Chiang Mai Royal Agricultural Research Center (Maehea) with the highest root weight of grafting using IBA at a concentration of 8,000 ppm was 15.68 g. As well as the highest percentage of survival of approach grafting branches using IBA at a concentration of 8,000 ppm of the Chiang Mai Royal Agricultural Research Center (Maehea) in November was 85.63%. However, there was non-statistically different with IBA at 6,000 ppm with survival of approach grafting branches of 79.38%. In conclusion there was non-statistically different between the concentration of 8,000 ppm IBA and 6,000 ppm IBA. Therefore, the concentration of 6,000 ppm IBA are most suitable for approach grafting Macadamia because it is effective in approach grafting Macadamia and the most breakeven.