Abstract

                                A field experiment was conducted at Horticultural College and Research Institute, Periyakulam during 2006-2007 and 2007-2008 to study the effect of paclobutrazol (Cultar) on tree growth and canopy spread in five year old trees of acid lime. The trees were treated with paclobutrazol at different concentrations viz., 1.25, 2.50, 3.75 and 5.00 g a.i per tree following randomized block design. The results were recorded during on and off seasons of the year. Application of paclobutrazol (PP333 ) had significant effect on tree height in both the seasons. Soil application of paclobutrazol 2.50 g had the highest tree height in the main (3.33 and 3.18 m) and off season (3.86 and 3.48 m) during the year 2007-08 and 2006-07 respectively. The lowest tree height (3.05 and 3.21 m) was registered under paclobutrazol 3.75g during the main and off seasons of the year 2006-07 and 2007-08. Tree spread between east to west was found to be wide (4.40 and 4. 58 m) in soil application of paclobutrazol at 3.75 g during main and off seasons of the year 2006-07 and 2007-08. Similarly, tree spread between north to south, soil application of paclobutrazol at 3.75 g recorded wide tree spread (4.62 and 4.88 m) in the main and off season of the year 2006-07 and 2007-08.

Key words : Acid lime, tree growth, canopy spread, paclobutrazol and season