Genetic variability in wood and oleoresin characteristics of high resin yielders in Chir pine (Pinus roxburghii Sargent)

Genetic variability in wood and oleoresins traits of twenty six high resin yielders (HRYs) and ten check trees of Pinus roxburghii was studied. These traits were quantitatively measured for bark percentage of wood, specific gravity of wood, tracheid length, cold and hot water soluble extractives, alcohol-benzene extractives, lignin and holocellulose percentage of wood, number of resin ducts, diameter of resin ducts, needle length, needle thickness, turpentine percentage, specific gravity of turpentine, relative flow rate of turpentine, rosin percentage, specific gravity of rosin and ash percentage of rosin. The highest heritability was observed for hot water soluble extractives, lignin percentage of wood and rosin percentage followed by bark percentage of wood, cold water soluble extractives and turpentine percentage. The maximum genetic advance was recorded in rosin percentage followed by lignin percentage of wood. The highest genetic gain was obtained in bark percentage of wood preceded by number of resin ducts whereas, phenotypic and genotypic coefficient of variation was highest in number of resin ducts followed by bark percentage of wood. Hence, bark percentage of wood, tracheid length, cold and hot water soluble extractives, lignin percentage of wood, number of resin ducts, diameter of resin ducts, needle length, turpentine and rosin percentage should be considered as effective parameter for the selection of high resin yielders (HRYs) in Pinus roxburghii Sargent.