A Study on Selection of Second Generation Progeny Testing of Eucalyp tus urophylla

The results of a second generation progeny trial of E.urophylla involved 44open-pollinated families at the age of 5-years in West ern Guang dong Province showed that there were highly signif icant differences among families at the growth and the quality charac-ters. The growth and quality of E.urophy lla were moder rately or strongly her editary. Stemheight below the forestlimb, stem straightness and ramif ication had highly signif icant positive genet iccor relations with the growth characters, wood density had also a positive genet icco rrelation with the index of typho on resist ance, and a negat ivegenet iccorr elat ions with other characters. Index selection in consider ation of the herit abilit is and economic value of multi-chrarcters enable genetic improvem ent to get good expected genet icgains of mult icharacters, the genet icgains int he treeheight、DBH、volume、wood density、index of typho on resis-tance of 25 good families selected by moret hant he mean of selective indexvalue are respectively 2.84%, 5.17%, 12.67%, 3.2% and 2.62%. The stemheight belowt he forestlimb、stemst raight ness and ramif icatio nwill be reached 12.24%, 7.95% and 4.43%.