Effect of Variety and Growth Regulator Concentration on Success of Air Layering in Plum

Abstract
The experiment was conducted at the Regional Spices Research Center, BARI, Gazipur during June 2016 to October 2017 to evaluate the effect of genotype and growth regulator (IBA) on the success and performance of plum air layering. Air layering was done on two plum varieties (BARI Alubokhara-1 and PD Gaz 004) using seven levels of IBA concentration (viz. 0, 1000, 2000, 3000, 4000, 5000 and 6000 ppm) under a complete randomized (factorial) design (CRD). Significant variation was observed on rooting, establishment and death of layers due to variety and IBA concentrations except rooting and separation time. The un-fruiting line PD Gaz 004 showed outstanding performance in rooting and survivability of layers over BARI Alubokhara-1. Poor rooting and lower establishment caused very high mortality of layers in BARI Alubokhara-1. Rooting and survivability, number of roots, length of roots and leaf production increased with the increasing levels of IBA concentration up to 5000 ppm. The maximum (10 out of 10) rooting success of layer with 65.83% and 59.17% establishment from PD Gaz004 was obtained when 3000 and 4000 ppm IBA was used, respectively. In BARI Alubokhara-1, the highest rooting success (3.08), establishment rate (29.42%), number of root (4.28/layer) and root length (5.08 cm) were recorded with 4000 ppm IBA concentration.