Estimation of Genetic Parameters and Screening of Families for Casuarina junghuhniana

A progeny test trial with 31 families of Casuarina junghuhniana was established at Yangxi of Guangdong. After planting,tree heights were measured for 6 times and DBH was for 5 times. Based on 12 quantity or quality traits of the 31 families,analysis of variance,covariance,correlation,variance component were carried out to estimate genetic variation coefficient (Gcv),family heritability(hf2),early-late correlation of tree height(H) and DBH ,phenotypic and genetic correlation and genetic gain. Results showed that there are significant correlation in heights from the 5 months to 5 years and DBH from 1 year to 5 years after planting. There were significant differences in 12 trait values between families. Genetic variation coefficients of tree height, DBH,single tree volume(V),pole height(Hs) and crown width(Cm) were respectively 35.56%、33.44%、93.02%、30.91% and 22.53%,other trait values were 3.95%～16.02%. Analysed the phenotypic and genetic correlation of 13 trait values. Calculated the heritablities for 12 traits,except survival percentage heritability was 0.55,the other 11 traits of heritabilites were 0.80～0.94. When selection portorption was 20%,genetic gains of main growth traits in H,DBH and V were respectively 24.03%,22.38% and 60.90%,and genetic gains of main quality traits in stem straightness,permanent branch density,survival percentage,stem persistence and tree health level were 6.85%～15.17%. Finally,using breeding values and selection indexes,evaluating the 31 families of performance and found out some dominant families.