Variation in Specific Gravity of Wood in Segregating F2 and F3 Populations of E. Citriodora Hook. X E. Torelliana F.V. Muell. Hybrids

The present paper reports the variations observed in specific gravity of wood in segregating populations of F₂ and F₃ hybrids of E. citriodora and E. torelliana. Perhaps this is the first report of its kind so far as the F₂ and F₃ hybrids of Eucalyptus are concerned. These studies were carried out on lO-year-old plants growing in a field trial laid out in 1987 at New Forest Campus, Dehradun. (Alt. 640m. Lat. 30° 30° 40° N.R.F. 216 cm.). A comparison in specific gravity of wood has been made with parent species involved in hybridization. A subtle range in variation in specific gravity of wood was observed due to segregation. The range in specific gravity of wood observed was 0.8144 - 0.8931 in E. citriodora, 0.6279 - 0.6590 in E. torelliana and 0.5170 - 0.6677 for F₂ and F₄ recombinants. Since a wide spectrum of variation has been observed in individual tree specific gravity of wood belonging to F₂ and F₃ generation hybrids this has offered ample scope for selection of desired recombinants for different end uses.