Superior Clones Selection And Breeding Of Paulownia For Deocration Plantation

Paulownia originated from China, is one of the famous fast-growing tree in our country.From the 70 s of last century, more than 30 Paulownia clones were bred to use in production in our country mainly for the traditional cultivation area in Huang Huai Hai Plain. in recent years,along with the Paulownia lumber prices continue to rise, not only in the traditional main planting area of steady development, and in the Yangtze River in the downstream area has formed the upsurge of development of Paulownia Timber Forest. However the breeding for Paulownia timber new varieties in this area has not been carried out in current. Therefore, In order to directed cultivation of color material, excellent material of Paulownia decorative material clones, the 5-year growth of 18 Paulownia clones as materials in this study it’s wood color traits(brightness, whiteness, red degree, yellow degree, color chromatism), growth traits(DBH, trunk height, 2.6m diameter, trunk volume, trunk taper) and properties(density,hardness, tangential cleavage resistance, radial cleavage resistance), sugars and phenol contents and N, K, P content of wood were studied, comprehensive evaluation was made on the 18 clones, and 3 superior clones were selected to be suitable for decorative materials. the main results are as follows:1. The brightness, whiteness, red degree, yellow degree, color chromatism are significantly different, at the same time, among the Paulownia clones of each trait variation coefficient larger, providing a greater choice of space. Sugars and phenol content reached significant level, sugars and phenolic content and brightness, color chromatism showed extremely significant correlation. Through clustering analysis the 18 Paulownia clones can be divided into three categories, the second class of 9501、30A、10B、P6、P5、3A、3B clones belongs to the good color of clones with large brightness and whiteness, small red degree,yellow degree, color chromatism.2. Analysis from the change trend of Paulownia clones in different height of wood color index, brightness and whiteness is the same, are "low-high-low" type, namely with the trunk height increase brightness and whiteness first increased and then decreased, and the yellow degree and color chromatism change trend is "high-low-high" type, with the increase of tree height decreased first and then increased. The change trend of the red degree is "straight line",that is with the increase of the height of the trunk, the red degree is almost constant. The results also showed that DBH is the wood color best position of paulownia clones.3. DBH, 2.6m diameter, trunk taper of Paulownia clones were statistically sigificant,while the trunk height and trunk volume were not significantly different. The contents of N, P were obviously different, and the contents of K is not obvious. There was a significant correlation between the total content of N and trunk height, trunk volume, between the total content of P and 2.6m diameter, diameter, trunk volume, between the total content of K and DBH and trunk height; Through clustering analysis the 18 Paulownia clones can be divided into three categories, the second class of 30A、4B、P2、5 号 clones belongs to the better kind of growth traits with the characteristics of the main trunk diameter, large trunk, high volume but the truk taper is large.4. The density, hardness, tangential cleavage resistance and radial cleavage resistance are significantly different, at the same time, among the Paulownia clones of each trait variation coefficient larger, providing a greater choice of space. Through clustering analysis the 18 Paulownia clones can be divided into three categories, the third class of 46 号、P2、52 号、4B clones belongs to the better kind of wood properties with the characteristics of the density,hardness, tangential cleavage resistance and radial cleavage resistance is large.5. Analysis from the change trend of Paulownia clones in different height of wood property index, density and hardness is the same, are "low-high" type, namely with the trunk height increase density and hardness increased, and the tangential cleavage resistance and radial cleavage resistance change trend is "high-low" type, with the increase of tree height the tangential cleavage resistance and radial cleavage resistance decreased.6. Comprehensive analysis wood color, growth and property index 18 Paulownia clones can be divided into 5 categories, The first category is 9501, 4B, No.52 clones; the second category is No.46 and P2 clones; the third category is 2B and P5 clones; the fourth category is10 B, No.5, 30 A, 3B, P3, 3A and No.16 clones; the fifth category is No.56, P6, No.13 and 16 A clones. The first category of clones belong to better clones with red degree, density, trunk taper,tangential cleavage resistance and radial cleavage resistance in five kinds of clones are ranked first, yellow degree, color chromatism and whiteness ranked second, brightness and hardness ranked third, DBH and trunk volume ranked fourth, high trunk and 2.6m diameter ranked fifth.Therefore, 9501, 4B, No.52 of the Paulownia clones as suitable for excellent decoration material properties.