| Schima superba is the most important biological fire-resistance and good fast-growing timber wood species in southern China. The field trails with 96-141 open-pollinated families from plus-tree of Schima superba, located at Jian'ou of Fujian, Longquan and Chun'an of Zhejiang, were conducted to investigate the family inheritance and genetic variation for seedling growth and leaf shape traits. Provenance trails at age five located at Jian'ou of Fujian, Chun'an and Qinyuan of Zhejiang was conducted to study provenance differences, geographic variation pattern and genetic correlation for growth and form traits. In addition, provenance differences in leaf stable carbon isotope discrimination (Δ) and its geographic vatiation pattern, as well as the effect of trial site and provenances growth rate, were also studied. Comebined with the pot experiment under different water control and phosphorus treatments, the reaction of Schima superba seedlings of different provenances to drought and low phosphorus stress was studied, differences in provenance growth and phosphorus efficiency under the effect of interaction of water and phosphorus was disscused. The results as following:The result of variance analysis showed there existed significant differences among families tested on seedling height, base diameter, number of leaves, leaf length and leaf width. It was found that seedling height and leaf length were respectively under moderate and strong family and additive genetic control, while base diameter, number of leaves and leaf width were under weak or moderate family and additive genetic control. Compared with the families from the higher latitude and higher altitude regions, the families from the lower latitude and lower altitude regions had larger growth increment, longer, wider and denser leaves, which indicated significant effect of seed source besides the family effect for seedling growth and leaf shape. Not only significant location effect but also significant interaction of family by location existed for seedling height and base diameter of Schima superba. Based on the family trial result at seedling stage, recommended for seedling height, 20 superior familes were selected respectively for the central distribution area with better water and heat conditions (Jian'ou of Fujian), the general distribution area (Longquan of Zhejiang) and the northern distribution area with worse water and heat conditions (Chun'an of Zhejiang).The result showed significant differences between provenances for height, DBH, stem straightness, total number of primary branches, length and diameter of primary branches, and these traits were under moderate or even stronger provenance genetic control, of which the provenance broad-sense heritability varied in the range 0.34-0.61. Significant differences for bifurcations of stem and angle of maximum branch were not found. Correlation analysis showed that geographic variation pattern for growth and form traits varied with different locations. At Jian'ou of Fujian (the central distribution area), a classical latitude clinal variation pattern was found for the main growth and form traits which were negatively and significantly related to the latitudes of seed sources and their correlation coefficients reached -0.313 to -0.534, which means that the southern provenances had faster growth rate, straighter stem, more and thicker branches. At Chun'an of Zhejiang (the northern area), the total number of primary branches were negatively and significantly related to the latitude of seed sources respectively, whereas other traits were not related to the longitude and latitude of seed sources. Significant positive relationship was found for the main growth and form traits in both two locations and their genetic correlation coefficients reached 0.320-1.164, while the stem straightness was independent to the length of primary branches. Based on two advisable selection indexes with equal economic weight and growth emphasis economic weight respectively, 10 superior provenances were selected for Jian'ou of Fujian and Chun'an of Zhejiang respectively. Most of the superior provenances in Jian'ou of Fujian were from southern distribution areas, while most superior provenances in Chun'an of Zhejiang were from central distribution areas.Significant differences in leafΔwere found among provenaces, and the differences in leafΔvalue between the highest and lowest provenances reached 6.9%, 3.0% and 3.7% in 3 experimental sites respectively. A classic latitude clinal variation pattern was found as there were significant correlations between the leafΔvalue and the latitude of seed sources in all the 3 locations, while significant correlations between the leafΔvalue and the longitude of the seed sources was not found. The southern provenances showed higher leafΔvalue than the northern provenances, indicating the water use efficiency (WUE) was lower in southern provenances. The leafΔvalue of different provenances was demonstrated to be greatly influenced by the environment of trial site. The leafΔvalue significantly increased with the improvement of site environment and with the increase of annual rainfall. Significant positive correlations between the leafΔvalue and growth traits including tree height, DBH, total number of lateral branches and length of the strongest lateral branch was found, which indicated that the provenances with higher growth rate and denser crown had larger leafΔvalue. Two and four superior provenances with high growth rate and low leafΔvalue (or high WUE) were selected for Jian'ou of Fujian and Chun'an of Zhejiang, respectively.The result showed significant differences between provenances for seedling growth, root parameters and phosphorus absorption efficiency. In comparison with provenances of Youxi in Fujian and Ji'an in Jiangxi, which come from higher altitude and was negatively selected respectively, the provenances of Jian'ou in Fujian and Longquan in Zhejiang exhibited larger growth increment, more developed root and higher phosphorus absorption efficiency. As the control, Schima wallichii from Guangxi Province remained its original characteristics, which were fast growing, drought and infertility resistant, but sensitive to freezing injury. Water control and phosphorus treatments had significant effect on the growth and development of Schima superba provenances seedlings. Dought and low phosphorus stress, especially the latter, significantly restrained the growth and development of Schima superba provenances seedlings. However, Schima superba provenances tended to allocate more photosynthetic product to root system, and exhibited higher phosphorus utilization efficiency, which might be an important physiological mechanism of the adaptation of Schima superba provenances to the dought and low phosphorus stress. The main effects of provenance, water level and phosphorus level were significant, whereas the interaction of the three factors were not significant.
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