| Quercus mongolica Fisch. is one of the three hardwood timber species in north of china, it is also a multi-purpose and ecological timber species and plays an important role in maintaining regional ecological balance and ecosystem restoration.Thirty two populations of Q.mongolica were selected and investigated in the natural distribution of Quercus mongolica in China. This paper analyzed phenotypic variation among and within provenances, phenotypic differentiation coefficient, genetic parameters and carried out the phenotypic traits of the geographic variation, combined with geography and climate factors, at the same time, this paper also had cutting and tissue culture researches, which lay the foundation of excellent provenance propagation. The main results are described as following:1. Analysis of variance for all traits showed that there was significantly difference among and within provenances. The coefficient of variation is between 17.89%44.38%, With the increase in geographical longitude and latitude, the shape of leaf blade changed from long obovoid to broadly obovoid, and the shape of acorn changed from wide ovoid to long ovoid. There existed significant or highly significant correlations among phenotypic variation and geography and climate factors, such as longitude, annual mean temperature and annual precipitation. The mean phenotypic differentiation coefficient (Vst) showed that the variation among provenances (48.78%) was nearly the same with the variation within provenances (51.22%), thus, Q.mongolica had broad prospects for genetic improvement. Principal component analysis showed that Q.mongolica phenotypic characteristics can be simplified to the length factor, leaf shape factor and seed shape factor. Cluster analysis showed that the 14 provenances of Q. mongolica investigated could be divided into four groups, geographical isolation effect had great role on genetic differentiation of Q.mongolica.2. Five factors such as cutting medium, hormone kinds, hormone concn, treatment time and Agrobacterium rhizogenes were used to study on softwood cutting of Quercus mongolica so as to discuss the main factors affecting its rooting. The study had conducted more than 70 treatments, a total of more than 7000 strains of cutting scion on July and August 2008. The mixture of peat soil and vermiculite and pearlite as cutting medium was the best. The rooting effect of treating by 500 mg·L-1IBA and 2.0 mg·L-16-BA for 2 hours was better, with rooting rate of 16.67%. Low concentration of NAA was conducive to rooting softwood of Quercus mongolica, while high concentration of NAA inhibited root. It had little effect when use ABT1 alone or together with IBA. The treatment time of 2 hours was good, with rooting rate of 13.33%. Agrobacterium rhizogenes A4 didn't have obvious effect on softwood cutting of Quercus mongolica.3. Strong nodal segments of aquiculture were used as a source of initial explants to the effects of media and hormone on organogenesis and plantlet regeneration of Quercus mongolica in vitro. The medium containing 0.2 g·L-1PVP can effectively inhibit browning stem. The low salt media 1/2MS containing 0.2 mg·L-16-BA were more suitable for initial culture, new shoots started early, the average height of sprouts was 3.00 cm, the highest was 5.20 cm. 1/2MS medium supplemented with 0.15 mg·L-16-BA and 0.15 mg·L-1KT in subculture was the best, the average height of sprouts was 3.00 cm, the average multiplication coefficient was 3.33. High concentrations of 6-BA on shoot growth was harmful, the base of shoots was full of callus, and vitrification appears. High rooting percentages and excellent development root systems were obtained on MS medium with NAA0.02 mg·L-1and IBA0.05 mg·L-1, rooting rate was 62.5%.
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