DNA extracted directly from the living nodules of Casuarina cunninghamiana, C.collina, C.glauca, Alnus cremastogyne, A.trabeculosa and Myrica rubra and also from 21 Frankia strains isolated from the root nodules of th...DNA extracted directly from the living nodules of Casuarina cunninghamiana, C.collina, C.glauca, Alnus cremastogyne, A.trabeculosa and Myrica rubra and also from 21 Frankia strains isolated from the root nodules of the actinorhizal plants in Fujian, including C. cunninghamiana, C.equisetifolia, C.glauca, A.cremastogyne and M.rubra. PCR amplification was conducted with the primers targeting the 3’ end of the 16S rDNA, the IGS, and the 5’ part of the 23S rDNA (i.e.,rrn region). PCR products were then analyzed by using a set of restriction endonucleases. Two distinct genetic groups were recognized on the basis of these restriction patterns. All Frankia strains associated with the host species of Casuarina were assigned to the same group. Frankia living in the nodules of Myrica and Alnus belonged to the other group. In Myrica-Alnus group, there was two sub-group which one included A.cremastogyme and the other contained A.trabeculosa and M.rubra. The results of RFLP analysis showed that the genetic diversity of Frankia associated with Casuarina could be lower, but Frankia existed in the soils of Fujian Province would have more richness in genetic diversity. The results also reflected that host plant has an ability to choose the strains to form a symbiont.展开更多
To provide potential implications of species selection for carbon plantation, differences in carbon sequestration pattern and net ecosystem production (NEP) were determined between two 36-year-old plantations of broad...To provide potential implications of species selection for carbon plantation, differences in carbon sequestration pattern and net ecosystem production (NEP) were determined between two 36-year-old plantations of broadleaved species, Castanopsis kawakamii and Cunninghamia lanceolata, in Sanming, Fujian. Annual net carbon sequestration was 13.639 and 6.599 t C·hm -2 a -1 , respectively, in the C. kawakamii and the C. lanceolata, among which the annual biomass C increment and the litterfall production was evenly distributed. To the annual net carbon sequestration, the contribution of stem (wood plus bark) increment was much lower, and that of branch increment was much higher in the C. kawakamii than in the C. lanceolata (26.6% versus 40.3%, and 11.5% versus 0.3%). In both plantation, the above and belowground litterfall accounted 60% and 40% respectively for the annual litterfall production, which was estimated 7.183 t C·hm -2 a -1 in the C. kawakamii and 3.554 t C·hm -2 a -1 in the C. lanceolata. Annual soil heterotrophic respiration was responsible for a C loss of 5.983 and 2.984 t·hm -2 a -1 from soil to atmosphere in the C. kawakamii and the C. lanceolata, respectively. Carbon balance analysis showed there were a positive net ecosystem production (C sink), 7.656 and 3.615 t C·hm -2 a -1 , for the C. kawakamii and the C. lanceolata, respectively. For the purpose of carbon management, C. kawakamii might be a more suitable species than C. lanceolata in local region.展开更多
建立了一种高效、快速可直接测定茶叶中21种游离氨基酸的超高效液相色谱-串联质谱(UPLC-MS/MS)检测方法。茶叶样品经粉碎、超声提取、离心净化、定容后,采用Capcell Pak C18柱(5μm,2.1×150mm)进行梯度洗脱分离,流动相为0.3%甲酸...建立了一种高效、快速可直接测定茶叶中21种游离氨基酸的超高效液相色谱-串联质谱(UPLC-MS/MS)检测方法。茶叶样品经粉碎、超声提取、离心净化、定容后,采用Capcell Pak C18柱(5μm,2.1×150mm)进行梯度洗脱分离,流动相为0.3%甲酸水溶液-乙腈,流速0.4mL·min^(-1)。茶叶中21种游离氨基酸在7.2~335.5 ng·mL^(-1)范围内的线性关系良好(R 2≧0.996),检出限0.1~3.8 mg·kg^(-1),定量限0.4~12.5 mg·kg^(-1),加标回收率72.1%~104.2%,相对标准偏差RSD≦5.3%(n=6)。该方法分析速度快、灵敏度高、选择性好,适用于茶叶中21种游离氨基酸的快速检测和定量分析。展开更多
文摘DNA extracted directly from the living nodules of Casuarina cunninghamiana, C.collina, C.glauca, Alnus cremastogyne, A.trabeculosa and Myrica rubra and also from 21 Frankia strains isolated from the root nodules of the actinorhizal plants in Fujian, including C. cunninghamiana, C.equisetifolia, C.glauca, A.cremastogyne and M.rubra. PCR amplification was conducted with the primers targeting the 3’ end of the 16S rDNA, the IGS, and the 5’ part of the 23S rDNA (i.e.,rrn region). PCR products were then analyzed by using a set of restriction endonucleases. Two distinct genetic groups were recognized on the basis of these restriction patterns. All Frankia strains associated with the host species of Casuarina were assigned to the same group. Frankia living in the nodules of Myrica and Alnus belonged to the other group. In Myrica-Alnus group, there was two sub-group which one included A.cremastogyme and the other contained A.trabeculosa and M.rubra. The results of RFLP analysis showed that the genetic diversity of Frankia associated with Casuarina could be lower, but Frankia existed in the soils of Fujian Province would have more richness in genetic diversity. The results also reflected that host plant has an ability to choose the strains to form a symbiont.
文摘To provide potential implications of species selection for carbon plantation, differences in carbon sequestration pattern and net ecosystem production (NEP) were determined between two 36-year-old plantations of broadleaved species, Castanopsis kawakamii and Cunninghamia lanceolata, in Sanming, Fujian. Annual net carbon sequestration was 13.639 and 6.599 t C·hm -2 a -1 , respectively, in the C. kawakamii and the C. lanceolata, among which the annual biomass C increment and the litterfall production was evenly distributed. To the annual net carbon sequestration, the contribution of stem (wood plus bark) increment was much lower, and that of branch increment was much higher in the C. kawakamii than in the C. lanceolata (26.6% versus 40.3%, and 11.5% versus 0.3%). In both plantation, the above and belowground litterfall accounted 60% and 40% respectively for the annual litterfall production, which was estimated 7.183 t C·hm -2 a -1 in the C. kawakamii and 3.554 t C·hm -2 a -1 in the C. lanceolata. Annual soil heterotrophic respiration was responsible for a C loss of 5.983 and 2.984 t·hm -2 a -1 from soil to atmosphere in the C. kawakamii and the C. lanceolata, respectively. Carbon balance analysis showed there were a positive net ecosystem production (C sink), 7.656 and 3.615 t C·hm -2 a -1 , for the C. kawakamii and the C. lanceolata, respectively. For the purpose of carbon management, C. kawakamii might be a more suitable species than C. lanceolata in local region.
