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101.
林木外生菌根作用及其机理综述 总被引:3,自引:0,他引:3
对林木外生菌根促进植物生长和固氮,增强植物抗病性、抗旱性和对不利环境的适应性等作用及其机理进行了综述. 相似文献
102.
从内蒙古沙漠土地的现状,发展趋势的分析,探讨了沙漠化土地形成的人为因素及其关系,提出了防治沙漠化土地扩展的思路和对策。 相似文献
103.
104.
WUGang WANGHong-chang FUHai-wei ZHAOJing-zhu YANGYe-qin 《林业研究》2004,15(3):197-202
Guizhou golden monkey (Phinopithecus roxellanae brelichi) is a peculiar, rare and endangered species. It is distributed most narrowly and requires a rigorous habitat. In this study the habitats of Guizhou Golden Monkey were divided into three habitats: most suitable habitats, suitable habitats and marginally suitable habitats. The characteristics of the vegetation community, environmental factors and extreme environmental factors in the three habitats were systematically analyzed. The seasonal activity rule, activity area and the food characteristic of Guizhou golden monkey were also study at the same time. The results indicate that the evergreen and deciduous broadleaf mixed forest is the optimal living vegetation community for Guizhoug olden Monkey, and the suitable annual temperature is 8-15℃, the extremely lowest temperature is -2.5℃, the extremely highest temperature is 25℃, and the optimal living altitude is 1500-1700 m. In the same area, the higher the vegetation diversitythe more suitable it is for the life of Guizhou golden monkey. Temperature and food are the main habitat factors in determining the activity scope of the guizhou golden monkey community. The Altitude, temperature and the characteristics of the vegetation community are the main limitina factors for habitat selection. 相似文献
105.
106.
Seiichi Kanetani Mitsuteru Akiba Katsunori Nakamura Koichiro Gyokusen Akira Saito 《Journal of Forest Research》2001,6(4):307-310
The process of decline of an endangered tree species,Pinus armandii var.amamiana, was monitored on the southern slope of Mt. Hasa-dake in Yaku-shima Island from 1994 to 1998. There are 163 trees ofP. armandii var.amamiana over 1.3 m in height. They are distributed on steep ridges and rocks with a thin soil layer mostly consisting of friable
granite. During the monitoring period, 21 trees ofP. armandii var.amamiana died and the mortality rate was 12.9%. Dead trees were categorized into three types: standing, uprooted and landslide. The
uprooted- and landslide-typed dead trees were found only after a severe typhoon struck Yaku-shima Island. This suggests that
the combination of fragile site conditions and severe typhoons play an important role in the process of decline ofP. armandii var.amamiana. The standing-typed dead trees were presumed to have been killed by pine wilt disease, accounting for 71.4% of the dead trees.
However,Bursaphelenchus xylophilus, the cause of pine wilt disease, was not detected from any of the wood chips or branch samples from the standing-typed dead
trees ofP. armandii var.amamiana. This might indicate that some factor(s) other than pine wilt disease could be responsible for the standing-typed death ofP. armandii var.amamiana in natural habitats.
A part of this paper was presented at the 109th Meeting of the Japanese Forestry Society. 相似文献
107.
银杏产量与气象因子相关性研究 总被引:3,自引:0,他引:3
以湖南省13年的气象资料,按银杏果生长发育周期,分5个阶段统计了水、光、热诸方面的8个气象因子,采用多元逐步回归方法,筛选出传粉受精期平均最大风速、种实第二增长高峰期的最低气温和5月1日~6月30日的总雨量3个对产量有重要影响的气象因子。相应时期较大的风速,较低的气温、充沛的雨量,可提高银杏产量。 相似文献
108.
辣椒全基因组WRKY转录因子的分析 总被引:2,自引:0,他引:2
基于已公布的辣椒全基因组数据,利用生物信息学方法对辣椒WRKY转录因子家族进行全面鉴定和系统命名,并在此基础上对基因分类、染色体定位、系统进化关系和结构域序列保守性进行了研究。结果表明:辣椒CaWRKY家族包含71个基因,根据WRKY结构域的数量及锌指结构的特征可将其分为GroupⅠ、GroupⅡ和GroupⅢ等3大类,GroupⅡ又可分为Ⅱ(a)、Ⅱ(b)、Ⅱ(c)、Ⅱ(d)和Ⅱ(e)等5个亚类。辣椒12条染色体上均有WRKY转录因子分布,其中第1号染色体上分布最多,共有10个,第4号染色体上分布最少,仅有2个。辣椒每类/亚类WRKY几乎含有相同的保守基序。辣椒WRKY编码的蛋白在132~869个氨基酸范围内,平均氨基酸数量为373个。 相似文献
109.
LIANG Meng-ya TANG Zhi-xian CHEN Guang-xian RONG Jian DAI Gang WU Zhong-kai 《园艺学报》2015,31(5):823-827
AIM: To observe the expression of hypoxia-inducible factor 1 (HIF-1) and neuroglobin (NGB) in piglet cortex during deep hypothermic circulatory arrest. METHODS: Wuzhishan piglets were randomly assigned to cardiopulmonary bypass group (CPB group), 40 min of circulatory arrest (CA) at 18 ℃ without cerebral perfusion (DHCA group) or with selective antegrade cerebral perfusion (SACP group). After 180 min of reperfusion, cortical tissue was harvested for determining HIF-1α and NGB expression by HE staining, Western blot and real-time PCR. RESULTS: Severer cerebral injury was observed in DHCA group than that in SACP group. After 180 min of reperfusion, HIF-1α protein and mRNA levels were significantly higher in DHCA group than those in CPB group (P<0.05). Accordingly, SACP animal had higher levels of HIF-1α protein and mRNA than those in DHCA group (P<0.05). Simultaneously, higher NGB protein and mRNA levels were found in DHCA group than those in CPB group after 180 min of reperfusion (P<0.05). The SACP animal had higher levels of NGB protein and mRNA than those in DHCA group (P<0.05). CONCLUSION: Up-regulation of HIF-1 and NGB are involved in the mechanism against cerebral injury resulting from DHCA in the cortex and possibly a part of cerebral protective effect of SACP. 相似文献
110.
AIM: To study the protective effect of brain-derived neurotrophic factor (BDNF) on vascular endothelial cells with H2O2-induced oxidative injury. METHODS: Human umbilical vein endothelial cells (HUVECs) were cultured in vitro, and the oxidation injury model of HUVECs was established by treatment with H2O2. The oxidatively injured HUVECs were cultured with different concentrations (1, 10 and 100 μg/L) of BDNF. At the same time, the control group (no injury), PBS treatment after H2O2 injury group and TrkB inhibitor group (with 100 μg/L BDNF and 1: 1 000 TrkB inhibitor) were also set up. The viability of the HUVECs was detected by MTT assay. The levels of LDH, MDA, SOD and GSH were measured. The releases of NO, ET-1 and ICAM-1 were analyzed by ELISA. The changes of ROS production and cell apoptosis were evaluated by flow cytometry. The protein levels of TrkB, p-TrkB, cleaved caspase-3, Bcl-2 and Bax were determined by Western blot. RESULTS: Compared with uninjured control group, in H2O2 oxidative injury plus PBS treatment group, the viability of the cells was decreased significantly, the LDH and MDA levels were increased significantly and the activities of SOD and GSH were decreased significantly. The NO secretion was decreased, and the ET-1 and ICAM-1 concentrations were increased significantly. The ROS content and apoptotic rate were increased significantly. The protein levels of cleaved caspase-3 and Bax were increased but Bcl-2 protein expression was decreased significantly. Compared with PBS treatment group, in H2O2-injured HUVECs treated with different concentrations of BDNF, the cell viability was gradually increased, the LDH and MDA levels were decreased and the activities of SOD and GSH were increased gradually. The secretion of NO was increased but ET-1 and ICAM-1 were decreased gradually. The ROS content and apoptotic rate were decreased significantly. The TrkB and p-TrkB levels were significantly increased significantly, the protein expression of cleaved-caspase 3 and Bax was decreased gradually and the Bcl-2 protein expression increased gradually. The role of BDNF was inhibited by TrkB inhibitor. CONCLUSION: BDNF protects HUVECs from oxidative injury by binding with TrkB to activate the BDNF-TrkB signaling pathways. 相似文献