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61.
在分析广东粤西湛江、雷州半岛区城CBERS-02遥感影像数据特征的基础上,利用遥感与地理信息系统软件处理遥感影像的方法,对图像数据进行几何校正和融合处理,采用遥感图像多源信息复合、人机交互解译与GIS技术相结合的解译方法,实现湿地信息的提取,提取的总精度高达83.5%,比单纯的采用监督分类精度提高20%,获得了理想的结果,为广东湿地环境可持续发展提供决策支持。  相似文献   
62.
草地畜牧业作为藏北地区的重要经济产业,一直以来政府和科研人员致力于通过试验示范区探索和推广天然草场围封改良、补播改良、优质混播人工草地建植等措施来提高草场利用率和维持草地生态系统的可持续发展。基于GPS实地测量人工、天然草场以及自由放牧、暖季休牧和禁牧不同放牧制度的草场试验样地范围,以2006年7月及2008年年内时间序列的CBERS-02星数据作为遥感数据源,分别监测人工与天然的休牧草场、天然的自由放牧-暖季休牧-禁牧草场的植被长势。利用归一化植被指数(NDVI)和差值植被指数(DVI)的均值、标准差、极值及优势度反映不同草场植被长势、覆盖均匀度等情况。结果表明:人工补播的草场植被普遍长势、最佳长势及最劣长势均优于天然草场,但人工草场的覆盖均匀度不及天然草场;天然禁牧、天然暖季休牧、天然自由放牧草场长势依次递减;休牧在九月中旬放牧之前与禁牧草场的植被覆盖均匀度基本保持一致,两者的NDVI标准差远低于自由放牧草场,但休牧草场在放牧之后,植被均匀度遭到破坏,NDVI标准差介于禁牧与自由放牧草场之间。此外,该研究采用3S技术,从另一角度有效地实现了对草场覆被长势的动态、宏观监测。  相似文献   
63.
对两个甘蔗新品系桂糖02—901和02—467的组培苗生根培养基配方及培养方式进行研究。研究结果表明,桂糖02—901组培苗生根培养的最佳NAA浓度为10mg/L.最佳蔗糖浓度为70g/L;而桂糖02—467的组培苗在NAA浓度为5mg/L,蔗糖浓度为30g/L时,其生根率均比其它处理的高。在培养基中添加活性炭会降低组培苗出根率。接种后放置在室外自然光照下的环境培养,会延迟出根时间,但组培苗总的出根率比在室内的高。  相似文献   
64.
Turnip mosaic virus (TuMV) is responsible for a serious disease that affects the production of Chinese cabbage. Previous studies have cloned a series of TuMV resistance genes and developed molecular markers. In this study, a derived cleaved amplified polymorphism sequence (dCAPS) marker and a Kompetitive Allele Specific PCR (KASP) marker were developed based on a single recessive gene, retr02, which confers broad‐spectrum TuMV resistance in Chinese cabbage by means of an additional G at the junction of exon 1 and intron 1. The two markers were able to detect the retr02 allele in Chinese cabbage accessions used in breeding programmes. Compared with the dCAPS marker, the KASP marker was flexible, cost‐effective and quick to process, which is likely to be beneficial in establishing high‐throughput assays for marker‐assisted selection.  相似文献   
65.
AIM: To investigate the role of reactive oxygen species(ROS)-mediated mitochondrial oxidative injury in isonicotinyl hydrazide(INH)-induced DNA damage and the protective effect of quercetin on L-02 cells. METHODS: The injury model of hepatocyte L-02cells in vitro induced by INH was established. The cells were divided into control group, INH group, low-dose quercetin group and high-dose quercetin group. The DNA damage of L-02 cells was evaluated by the comet test. The mitochondrion was prepared, and the level of mitochondrial ROS and the value of mitochondrial membrane potential(ΔΨm) were detected by fluorescent probes DCFH-DA and rhodamine 123. The content of MDA was measured by TBA method. The activity of SOD was assessed with the xanthine oxidase method. The protein expression of Bcl-2 and Bax was determined by Western blotting, and the value of Bax/Bcl-2 was calculated. RESULTS: INH induced obvious DNA damage, increased the level of mitochondrial ROS, the content of MDA and the value of Bax/Bcl-2, and markedly reduced the value of ΔΨm and the activity of SOD in the L-02 cells. Quercetin attenuated DNA damage, reduced the level of mitochondrial ROS, elevated the value of ΔΨm, declined the content of MDA, increased the activity of SOD and decreased the value of Bax/Bcl-2 in the L-02 cells. CONCLUSION: INH induces DNA damage in L-02 cells by generation of mitochondrial oxidative stress. Quercetin has a protective effect on L-02 cells to attenuate the INH-induced DNA damage by inhibiting ROS-mediated mitochondrial oxidative damage.  相似文献   
66.
采用“施丰乐”1 g/666.7 m2,配成40 mg/kg水溶液,在大麦新品种闽麦02上喷施,能有效提早大麦成熟期、增加籽粒产量。其中在分蘖期1次性喷施,主要是通过增加单位面积上的有效穗而获得增产;而在孕穗期1次性喷施、或在分蘖期、孕穗期分2次喷施,则主要通过增加穗粒数和千粒重而获得增产。且后两者均比前者喷施的效果更好、增产更显著,而后两者间的增产幅度相近,差异不显著。  相似文献   
67.
山东省玉米辐射诱变育成杂交种的系谱分析   总被引:8,自引:1,他引:8  
山东省辐射诱变育成的鲁原单号玉米杂交种,其亲本主要是来源于原武02、原齐系和华风系。以原武02及原齐系为亲本,育成的杂交种都具有早熟或中早熟特性。这些品种在黄淮海夏玉米区种植推广,获得极显著的增产效益。  相似文献   
68.
AIM: To observe the effects of NOD8 on H2O2-induced apoptosis in human L02 hepatocytes. METHODS: pEGFP-C2 and pEGFP-NOD8 plasmids were transfected into L02 cells by JetPRIME, respectively. The apoptosis of these transfected cells was induced by H2O2. The cells were divided into pEGFP-C2 group, pEGFP-C2+H2O2 group and pEGFP-NOD8+H2O2 group. MTT assay was used to detect the cell viability. NOD8 protein expression was determined by Western blotting. The cell apoptosis was observed by Hoechst 33342 staining and apoptotic rate was evaluated by flow cytometry. The caspase-3 activity was analyzed by a colorimetric method. RESULTS: L02 cells were stimulated by H2O2 at concentrations of 0.2~2 mmol/L for 6 h, and H2O2 at concentration of 1 mmol/L was chosen to induce apoptosis determined by MTT assay. The protein expression of NOD8 significantly increased in the cells transfected with pEGFP-NOD8 plasmid. More cellular nucleus with strong blue fluorescence by Hoechst 33342 staining in pEGFP-C2+ H2O2 group were observed, indicating that apoptosis was increased, while the apoptosis in pEGFP-NOD8+H2O2 group significantly reduced. The apoptotic rate in pEGFP-C2+H2O2 group was obviously increased, whereas that in pEGFP-NOD8+H2O2 group was significantly decreased. The caspase-3 activity in pEGFP-C2+H2O2 group was remarkably increased. By contrast, the activity of caspase-3 was significantly reduced in pEGFP-NOD8+H2O2 group.CONCLUSION: NOD8 inhibits H2O2-induced apoptosis in L02 cells and the mechanism may be related to inhibition of caspase-3 activity.  相似文献   
69.
FR 02全长基因的克隆表达载体的构建及转化苹果   总被引:3,自引:1,他引:3  
从铁胁迫诱导的拟南芥植株根中克隆了全长的FR02(Fe^3+-螯合物还原酶)基因,并将FR02基因构建到了植物高效表达载体pCB302中。通过农杆菌介导的转化和PCR及Southern blot检测证明FR02基因正向的插入了苹果基因组中。以破坏生长点的茎尖为外植体的苹果基因转化方法转化率高达10.8%。FR02全长基因的成功克隆、构建和转化为高铁、抗黄化苹果和其他高铁作物新品种的培育开辟了一条新路。  相似文献   
70.
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