Analysis of genetic variation of growth traits of Eucalyptus grandis in a progeny trial at Erabadda, Sri Lanka

Eucalyptus grandis is important timber species in both forest plantations and home gardens in Sri Lanka’s tropical uplands. At present seeds used for E. grandis are mainly collected off trees of the local land races, which have been of unverified genetic provenance. In 1995, an E. grandis provenance- family trail/ seedling seed orchard was established in intermediate zone, IU3e agro ecological region of Sri Lanka. It comprises 88 families representing 19 Australian provenances. According to the previous studies, at the 27 months ago there were considerable differences among provenanaces and among families within provenanaces in the E. grandis provenance- family trail for height, diameter at Brest height (DBH) and tree volume. The natural stand povenanaces from Windsor Tableland (CSIRO No. 18138) and from Atherton (CSIRO No. 16583), both from higher altitude areas in northern Queensland, showed best growth. However, the variation between the families within povenanaces exceeded most of the differences between povenanaces with a family from one of the poorest povenanaces. Kin Kin in Queensland (16892), proving to be second biggest family overall volume. Heritability estimates obtained for height (0.22) Diameter at Brest Height (DBH) (0.12) and volume (0.11) were intermediate to low but still indicate that reasonable genetic gain will be achieved through an open pollinated breeding strategy in Sri Lanka. In the eucalyptus species trail, E. grandis showed the best growth at age 27 months of the five species tested. Present study was carried out in Erabadda research plot (2.8 Ha) of Badulla district, Sri Lanka. The study area contains seven different seed sources of E. grandis, which were belong in to seventy-two provenances.  In this study, several parameters, such as DBH, Height of the tree and volume of the trees were determined. Collected data were analyzed by the Dataplus and GeneStat software’s to determine the genetic variance was determine among all varieties of E. grandis in the study area. These findings will be useful for the future improvements of E. grandis in Sri Lanka.