Interactive Effects of Indole Acetic Acid, Kinetin and Propagation Timing on Growth, Vigour and Survival of Mango (Mangifera indica L.) Grafts

Abstract

Mango (Mangifera indica L.) is one of the most important fruit crops, but its large-scale cultivation is constrained by the limited availability of quality planting material. Successful grafting, which depends on proper graft union formation through callus development and vascular connection, can be enhanced by the application of plant growth regulators such as IAA and kinetin. The present investigation was conducted to evaluate the interactive effects of IAA, kinetin and propagation timing on growth, vigour and survival of mango grafts. The experiment was carried out at the Fruit Research Station, Imaliya, Department of Horticulture, College of Agriculture, Jawaharlal Nehru Krishi Vishwa Vidyalaya, Jabalpur during January and February (off-season) of 2022. Scions were treated with different concentrations of IAA and kinetin prior to grafting. The results revealed that minimum time to sprout initiation (11.50 days), maximum sprouting percentage (82.34%), success percentage (77.37% at 60 days after grafting) and survival percentage (72.72% at 120 days after grafting) were recorded with 100 ppm IAA-treated scion shoots. Among propagation timings, February grafting was found significantly superior to January grafting in terms of sprouting, success and survival. The interaction effect indicated that scions treated with 100 ppm IAA and grafted in February recorded minimum days to sprout initiation (10 days), maximum sprouting (90.00%), success (84.53% at 60 DAG) and survival (78.39% at 120 DAG). This treatment also produced the highest number of leaves and maximum shoot length (37.72 cm) at 120 days after grafting, followed by kinetin 100 ppm + IAA 50 ppm and kinetin 100 ppm treatments.