Influence of Low Concentration of Paclobutrazol and Its Application Close to the Main Trunk on Fruiting of Mango in Ultra High Density Plantations

Abstract

Control of flowering and fruiting in mango is achieved by the application of Paclobutrazol (PBZ) in many commercial orchards. However, growers tend to use very high concentrations of the chemical, resulting in high costs of operation and long-term effects. This study examines the impact of low concentrations and varying application methods of PBZ on mango fruit yield in ultra-high-density plantations. Here 3 methods of application and 4 levels of PBZ concentrations (PBZ 23% SC) were tried in a 3 year study. Application of PBZ at N1 (close to the trunk, also termed as collar drench), N2 (20 cm away from the trunk) and N3, (1 m away from the trunk), all resulted in similar number of fruits and fruit weights. Using very low concentrations of PBZ, 4 (0.37 g a.i. /m canopy diameter (cd), 5 (0.46 g a.i. /m cd) and 6 (0.55 g a.i. /m cd) ml/2 liter water, it was found that the lowest 0.37 g a.i. /m cd is enough to get statistically higher fruit yield. These findings: a very low dose of PBZ can result in high productivity and a requirement of least volume of the solution when applied as a collar drench would make the use of PBZ more sustainable and encourage more growers to adopt the hormonal use for mango production.