| Variation of growth traits,tree form traits and wood properties, genetic control and genetic correlation between traits were studied systematically on 141 progenies from open-pollinated families of masson's pine(Pinus massoniana)plus trees. Thirty superior families on growth traits,tree form traits and wood properties were selected by index selection. The main results were as follows:1.There were significant or badly significant differences among families in growth traits,tree form traits and wood properties such as height,DBH(diameter at breastheight),stem volume ,straightness,crown width,ratio of height and DBH,ratio of crown width and DBH, and also wood properties such as tracheid length,tracheid width,the ratio of length to width,microfibril angle,but no significant difference were found in wood basic density among families。2.The order of family heritabilty,individual heritability and family's heritability was DBH>stem volume>ratio of height and DBH>height>crown width>straightness>ratio of crown width and DBH;Heritability varied from 0.38 to 0.43 in wood basic density and from 0.22 to 0.23 in microfibril angle. Heritability varied from 0.69 to 1.25,0.61to 0.97,0.53 to 0.73 in tracheid length,tracheid width,the ratio of length to width tracheid, respectively. The results showed that growth traits,tree form traits and wood properties of masson's pine families were above middle to strong genetic control in most conditions。3.According to selection intensity at 10% of selection ratio,the estimation of genetic gains of height,DBH,volume,straightness,crown width,ratio of height and DBH and ratio of crown width and DBH were 15.26%,20.21%,40.02%,7.74%,13.83%,14.46% and 10.46%, respectively;basic density was 5.03%;microfibril angle was 1.02%;tracheid length,tracheid width,the ratio of length to width for tracheid were 8.51%, 6.37% and 8.75, respectively。4.Correlation between growth and wood properties was showed as follows:The positive genetic relationship of height, DBH and volume with wood basic density, tracheid length, tracheid width, the ratio of length to width were significant. The negative genetic relationship of DBH and volume with microfibril were not significant. Positive genetic relationship between height and microfibril angle were not significant. Correlation of inter-wood properties was showed as follows:The negative genetic relationship of wood basic density with tracheid length was significant,and with tracheid width and the ratio of length to width were not significant. The positive gentic ralationship of tracheid length and tracheid width with microfibril angle,and the negative gentic ralationship of the ratio of length to width with microfibril angle were not significant. The negative genetic relationship of microfibril angle with wood basic density was significant。5.Synthetic selection index is a good measure for union selection on growth traits,tree form traits and wood properties. Synthetic index equation which based on using DBH,height,straightness, crown width,wood basic density,tracheid length,tracheid width and the ratio of length to width and microfibril angle 9 characteristics was:I=0.965X1-0.0282X2+1.0133X3+0.8065X4-18.5517X5+ 2.5014X6+104.755X7+0.1178X8- 3.3175X9;Restricted synthetic index equation which based on using height,DBH , wood basic density , tracheid length and tracheid width 5 characteristics was :I=0.3647X1+0.0227X2-6.4765X5+3.7846X6+0.0522X8, and restricted synthetic index equation emphasized on growth traits and wood properties was:I=5.4909X1-1.561X2+9.1551X3+6.761X4-93.83X5+ 45.038X6+0.4703X8+42.11X9.These synthetic index equation were most closely related to the yield and strength of masson's pine timber forest. By way of synthetical analysis to the characteristics of selection,30 better half-sib families were selected。6 .From 3rd year,tracheid length,microfibril angle and from 6th year,wood basic density were significant to highly significant in year-year correlation(besides 11th year)。... |
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