Study On The Genetic Variations Of Hybridized Progeny And Superior Hybridized Combinations Selection In Cunninghamia Lanceolata (Lamb.) Hook.

The grafted plants which were good at ablooming in the old Cunninghamia lanceolata (Lamb. ) Hook. gene bank and the superior clones which were selected by progeny test were used as parental to carry out hybridizing between old C. lanceolata and superior clones,superior clones and superior clones, and four blocks of progeny tests were planted successively by NC H design in 1990s. The growth traits of the progeny tests were investigated in the following years,and the genetic variations and correlations of growth traits among Hybridized combinations were studied based on the data. The results showed that there were significant differences or very significant differences on tree height, diameter at breast height and timber volume among Hybridized combinations in three blocks of progeny tests, the variations were mainly controlled by genetic factors. But there were no significant differences in growth traits among Hybridized combinations in the 4^th block of progeny test , and it is hard to select superior hybridized combinations in the 4^th block of progeny test. So, it is necessary to carry out progeny test and select superior hybridization combination in heredity. Based on the correlative analysis, the correlations of growth traits between different years were very plus close,and the correlation coefficient ascended along with thre growth of the progeny tests. Therefore, it is possible to select superior hybridized combinations in early age, and different selective intension should be established in different periods. According to the Interspecific heterosis analysis,there were plus Interspecific heterosis in the hybridized combinations, and it was existed in early age. The results also showed that hybrids whose male parent is old C. lanceolata possessed of conspicuous heterosis than whose female parent is Old C. lanceolata . Based on the variance analysis of combining and results of the inheritable parameters estimation, growth traits were mainly controlled by general combining ability , but not special combining ability,thus superior hybridized combinations or parental should be selected according to general combining ability,and it was specially important in hybridization among different clones .The combining ability estimation results showed that different general combining ability of parental were significant different in growth traits such as tree height,diameter at breast height,timber volume, it was also significant different in different tree age of parental.So, it is possible to select high general combining ability parental among trial parental.The high general combining ability parental not always procreate high special combining ability hybridization combination, which indicated that gene can be recombined by hybridization,but the hybrids not always presented heterosis, and they must be selected. It also indicated that the genetic variations law of C. lanceolata are complicated, and different breeding plans should be established according to genetic variations law of different traits.All the genetic analysis results showed that more perfect efficiency would be get if the old C. lanceolata is the male parent in hybridization, it is significative for using genetic resource of old C. lanceolata. Based on the efficiency of general combining ability, Youxi, Maodi, San7, Jian36, San52 and San54 were selected as superior female parents,Jian38, Mini, Wanghun, Jin9 were selected as superior male parents;37superior individuals were selected which were more superior than colony average and contrast, the average plus of timber volume was 64．687%, thereinto, the max was 100．843%. We can see that the individual selection efficiency was significant;Index equations were founded based on tree height, diameter at breast height, timber volume. Planned index selection result, combining ability analysis result, genetic plus,superior of hybrid, timber density as a whole,5 superior hybridized combinations were selected:San7×Minl, San54×Minl, San54×Maodi, Jian36×Jin9, Jian38×Jin9．Their separate genetic plus of tree height were 2．481%,2．052%,4．873%,3．430%,2．377%, separate genetic plus of diameter at breast height were 4．900%,5．872%,0．981%,4．584%,3．327%, separate genetic plus of stem volume were 16．650%,23．290%,10．793%,11．662%,8．936%, the timber density of every selected cross grouping was superior than colony and contrast.Selected parents hold strong general combining ability, they were in possession of strong genetic ability about growth traits. For getting higher superority of hybrid, it is necessary to develop hybridization trials with these parents;Selected superior individuals could improve productivity of plantation of C. lanceolata by agamogenesis;Selected superior hybridized combinations could be used as grafts of advanced generation orchard, and supplied to advanced generation genetic improvement breeding colony of C. lanceolata.