Path coefficient analysis of correlation between oleoresin yield and other characters of high resin yielders and check trees in Pinus roxburghii Sargent

Abstract

Data on twenty six high resin yielders and ten check trees of Pinus roxburghii were recorded for thirteen characters namely oleoresin yield, height, diameter, grain angle, specific gravity of wood, bark percentage of wood, tracheid length, needle length, needle thickness, diameter of resin ducts, number of resin ducts, lignin percentage of wood and holocellulose percentage of wood. The simple correlation coefficient between different pairs of characters was also computed. Path analysis of simple correlation revealed that number of resin ducts, diameter of resin ducts, needle length, bark percentage of wood, height and diameter contributed directly to the oleoresin yield, thereby indicating their direct involvement and relative importance for increase in the ultimate oleoresin yield.