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1.
大豆花叶病毒(SMV) 在大豆( Glycine max L.) 上引起严重病害。利用RT_PCR 扩增并克隆了SMV_ZK( 一个中国SMV 分离株) 基因组中全部蛋白质编码区的cDNA。通过对HC_PRO、NIb 和CP编码区进行序列测定与分析,发现SMV_ZK 与SMV_G2 高度同源,从而在分子水平上证明在我国大豆作物中存在SMV_G2 类似株系。将SMV_ZKcDNA克隆于细菌表达载体,获得并提纯了6 种cDNA 的表达产物。这项工作将为进一步研究SMV 基因组的功能奠定基础。  相似文献   

2.
复合氨基酸电渗析脱盐中试研究   总被引:2,自引:0,他引:2  
在复合氨基酸电渗析脱盐小试研究的基础上又进行了其中试研究,电渗析工艺条件的优化实验采用了先进的陡升法。中试实验过程着重研究了阳极室浓度(C_+)、阴极室浓度(C_-)、料液室浓度(C_d)、浓缩室浓度(C_c)、浓缩室与料液室体积比(V_c/V_d)以及电流密度(Ⅰ)脱盐率(NaCl)、电流效率、能耗(P)与生产能力(W)的综合影响,最后确定了中试脱盐工艺的最佳操作条件,同时,给出了最佳操作条件下的氨基酸变化情况。  相似文献   

3.
空气污染对植物病虫害的影响吴亚,金翠霞(江苏省农科院植物保护研究所,南京210014)EffectsofAtmospbericPollutiononPlantDiseasesandPests¥WuYa;JinCuixia(InstituteofPlantPro-tection,JiangsuAcademyofAgriculturalSciences,Nanjing210014).ChineseJournalofEcology,1993,12(6):49-53.Thispapersummarizestheeffectsofmainatmosphericpollutants,suchasO_3,SO_2,fluorides,acidrainetc.onplantpathogenicmicroorganisms;theeffectsofairpollutionontheoccuranceandinfestationofphytophagusinsects,andtheinfluencesofgreenhouseeffectofCO_2ontheoutbreakofpests。Keywords:atmospheri  相似文献   

4.
中国热带森林水文生态功能   总被引:17,自引:2,他引:15  
中国热带森林水文生态功能周光益(中国林科院热带林业研究所,广州510520)Eco_hydrologicalFunctionsofTropicalForest,China.ZhouGuangyi(TheResearchInstituteofTropi...  相似文献   

5.
利用APAGE、荧光原位杂交技术和RFLP标记,对导入黑麦(SecalecerealeL.)多小穗等性状创制的小麦新种质10_A进行了分子标记检测。APAGE分析发现,10_A与其他1RS/1BL易位系一样,含有1RS的醇溶蛋白标记位点Gld1B3。以黑麦基因组总DNA作探针,用中国春(Triticumaestivumcv.ChineseSpring)基因组DNA作封阻,与10_A根尖细胞有丝分裂染色体进行荧光原位杂交。结果表明,黑麦的1RS易位到10_A中。用25个RFLP探针进行Southern分析,进一步发现10_A的1BS特异限制性片段发生丢失,代之以黑麦1RS的特异限制性片段,而位于其他染色体上的特异限制性片段未发生缺失。据此认为,多小穗小麦新种质10_A属于1RS/1BL易位系。同时还讨论了10_A在小麦遗传改良中的利用情况。  相似文献   

6.
三峡工程与江汉平原农业持续发展   总被引:2,自引:0,他引:2  
三峡工程与江汉平原农业持续发展朱俊林(湖北大学生态学研究所,武汉430062)InfluencesoftheThree_GorgeProjectontheAgricultureinJianghanPlainAreaandtheA┐gricultura...  相似文献   

7.
用小麦( Triticum aestivum L.) 第二部分同源群的36 个探针,对携带抗白粉病( Erysiphe graminisf.sp tritici) 基因Pm6 的普通小麦提莫菲维小麦( T.timopheevi Zhuk .) 渐渗系进行检测,通过这些渐渗系与受体亲本“Prins”之间杂交谱带多态性的比较,发现所测出多态性标记位点均位于这5 个渐渗系的2B 染色体上,但其渗入片段的位置与大小有明显区别。IGV1_456 和IGV1_458 被鉴定为2B 染色体从短臂标记Xcdo405 到长臂标记Xbcd135 之间的区域已被提莫菲维2G 染色体区段所代替;而IGV1_463 则在2B 染色体长臂Xbcd307 到Xcdo678 标记之间的区域被提莫菲维渗入成分所代替;IGV1_464 、IGV1_465 2BL染色体上的渗入片段更小,即IGV1_464 在2BL染色体上标记Xpsr934 与Xbcd135 之间的区域有提莫菲维2G 染色质成分渗入,IGV1_465 仅在Xbcd135 附近有更小的外源成分渗入。根据5个渐渗系渗入成分重叠区段比较可把Pm6 定位于2BL染色体上Xbcd135 2BL标记的邻近区域内  相似文献   

8.
法国产夏枯草中的两个新的乌索烷型三萜皂甙   总被引:7,自引:0,他引:7  
从法国产夏枯草(PrunellavulgarisL.)的甲醇提取物中分离得到两个新的乌索烷型三萜皂甙:夏枯草甙(pruvuloside)A和B;同时还分离到5个已知化合物:niga-ichigosideF_2,sericoside,槲皮素(quercetin),槲皮素-3-O-葡荡糖甙(quercetin3-O-glucoside),山奈酚-3-O-葡荡糖甙(kaempferol-3-O-glucoside),及arjunglucosideⅠ和niga-ichigosideF_1的混合物。它们的结构是通过波谱的方法证明的。  相似文献   

9.
在离体Wistar大鼠海马脑片上,用微电极记录刺激顶树突层Schaffer侧支引起的CA_1区锥体细胞外群峰电位(PS)。观察用半浸式浴槽或多管微电极气压微量注射给予N受体激动剂烟碱(Nic)和M受体激动剂槟榔碱(Are)对PS的影响,探讨M和N受体功能。结果表明:Nic对PS幅度无明显影响,浓度1.0mmol/L时约1/4脑片诱发出第二个群峰电位(PS_2),浓度增加,PS_2发生率增加,PS_2幅度较PS低。美加明能部分对抗烟碱诱发的PS_2,表明PS_2出现与N受休关系密切。Are降低PS幅度,当浓度达到0.001mmol/L即能使PS幅度降低为正常的74%,PS幅度降低存在有效量关系,低浓度阿托品能选择性地对抗之,表明Are所致PS幅度下降是通过兴奋M受体的结果。  相似文献   

10.
Bt叶绿体转基因植株的抗虫性及后代表型分析   总被引:9,自引:0,他引:9  
将Bt CryIA(c) 基因与水稻( Oryza sativa L.) 叶绿体psbA 基因的启动子和终止子构建成表达盒,连同烟草( Nicotianatabacum L.) 叶绿体基因组同源片段rpl2_trnH_psbA和trnK_ORF509A 以及选择标记基因aadA一起构建成烟草叶绿体转化载体pTRS8。基因枪法转化烟草叶片,经壮观霉素筛选获得转化再生植株。有些转基因植株对3龄棉铃虫( Helicoverpa zea) 具有较强的毒杀作用,并能显著抑制昆虫蜕皮和生长发育。对高抗虫性植株的子一代(T1) 和子二代(T2) 进行的遗传学和分子生物学分析表明,Bt 基因已稳定地遗传给子代叶绿体,且抗生素抗性遗传遵循非孟德尔的母系遗传规律  相似文献   

11.
白颈长尾雉栖息地的季节变化   总被引:25,自引:7,他引:18  
1992年10月至1993年5月,在浙江省乌岩岭自然保护区,利用无线电追踪技术和野外直接观察等采样方法对白颈长尾雉各季节栖息地及其食性进行了研究。  相似文献   

12.
为了解浙江省古田山国家级自然保护区内白颈长尾雉(Syrmaticus ellioti)的分布格局和季节变化, 2014年5月至2016年4月, 我们对其进行了为期2年的网格化监测。共有44个公里网格拍摄到白颈长尾雉, 独立探测数量为211次, 雌雄性比为1 : 1.64。白颈长尾雉主要分布在实验区和缓冲区, 其探测率在常绿落叶阔叶混交林、杉木(Cunninghamia lanceolata)林、针阔叶混交林、人工油茶(Camellia oleifera)林和常绿阔叶林中依次递减, 主要分布在海拔600-800 m。冬、春两季, 白颈长尾雉活动强度和区域相对较小, 而夏、秋两季活动强度和区域相对增加, 其分布在海拔段(F4,12 = 3.76, P < 0.05)和季节间(F3,12 = 3.34, P < 0.05)都存在显著差异。对海拔和气候因子进行回归分析发现, 日平均气温和海拔对白颈长尾雉是否出现均有极显著影响(P < 0.01); 白颈长尾雉月探测率和探测到白颈长尾雉位点的海拔均与月平均气温呈极显著正相关(P < 0.001), 而与月平均降水量无显著线性关系(P > 0.05)。这表明白颈长尾雉的活动在很大程度上受海拔和气温影响, 随月平均气温的升高有向高海拔迁移的趋势。模型选择和多模型推断显示, 最优模型仅保留“100 m内水源”这一个变量, 次优模型是“100 m内水源 × 海拔”, 最优和次优模型的权重分别为0.18和0.14, “100 m内水源”和“海拔”是影响白颈长尾雉在保护区内分布的重要因子, 重要值分别为0.82和0.51。因此, 白颈长尾雉的分布并非仅由某一个或几个环境变量决定, 而是由多个环境变量共同决定。气温的变化和对不同海拔段的选择是导致白颈长尾雉形成不同季节分布格局的原因。  相似文献   

13.
观察了2001~2004年冬季分布于历山保护区的勺鸡的集群行为行。野外共观察120次,见到勺鸡1034只,其中95.3%的个体营集群生活,环境的异质性和天敌的捕食压力可能是导致勺鸡等雉类冬季集群的重要因素。  相似文献   

14.
官山保护区白颈长尾雉栖息地适宜性评价   总被引:2,自引:0,他引:2  
2009年4月-2009年5月和2009年12月-2010年1月,在江西官山国家级自然保护区对白颈长尾雉(Syrmaticus ellioti) 繁殖期和越冬期的栖息地进行调查。通过实地调查,结合已有研究结果,确定了官山自然保护区白颈长尾雉栖息地适宜性评价因子,即植被类型、海拔、坡度和坡向等4个栖息地因子。基于"被利用生境-可获得生境比较法",以对各评价因子不同梯度的资源选择指数为依据,确定了白颈长尾雉适宜性评价准则。应用ArcGIS 9.3空间分析功能和栖息地片断化指数,对官山保护区白颈长尾雉栖息地进行了适宜性评价。结果表明:在官山自然保护区适宜白颈长尾雉繁殖的栖息地斑块有502个,总面积为3307 hm2,占保护区总面积的28.6%,分离度指数和片断化程度指数分别为0.365和0.912;适宜白颈长尾雉越冬的栖息地斑块有514个,总面积2755 hm2,占保护区总面积的23.8%,分离度指数和片断化程度指数分别为0.443和0.939。官山保护区白颈长尾雉栖息地片断化较严重,片断化现象在白颈长尾雉越冬期加剧。因此,迫切需要采取措施白颈长尾雉现存栖息地进行保护,特别是要高度重视其越冬栖息地的保护。  相似文献   

15.
Sexual segregation, spring dispersal and late winter to spring habitat selection were studied in the pheasant Phasianus colchicus L. on two areas for which the proportions of different habitats were similar. On one of the sites (Damerham) hand-reared pheasants were released for shooting. On the other (Fulwell) no releasing or shooting took place.
The sex ratio of birds feeding in fields in autumn favoured males because females fed in groups within woods. Groups of birds were significantly segregated by sex during early to late winter periods, but by late March they were not. Male groups and solitary males in winter were more evenly dispersed than female groups.
At Fulwell, female winter groups consisted of regular group members (mainly adults) and transitory individuals called 'drifters' (mainly immatures).
Females in their first breeding attempt dispersed further from their winter range to their breeding range than did adult females and females dispersed further than males. Males gaining a territory for the first time moved significantly further than old territory owners. Territorial males moved less than non-territorial males between successive spring ranges.
During March June, habitat use by 33 radio-tagged females changed markedly from mixed and deciduous woodland to fields sown with winter and spring corn. The implications for management are outlined.  相似文献   

16.
The Hainan peacock pheasant is an endangered taxon found only on Hainan Island of China. Due to lack of detailed taxonomic studies, whether it is a subspecies of the grey peacock pheasant (Polyplectron bicalcaratum katsumatae) or a full species (Polyplectron katsumatae) remained unclear. We used molecular markers, including the complete mitochondrial cytochrome b gene and intron G of the nuclear ovomucoid gene, to reevaluate the taxonomy of the Hainan peacock pheasant. The results showed phylogeographic monophyly and large genetic distance between the Hainan peacock pheasant and the grey peacock pheasant. Sequence differences corroborated the species-level distinction between these two peacock pheasants, which were inferred to have diverged about 1.4+/-0.3 million years ago, near the time Hainan Island became separated from mainland China. Because the population density of the Hainan peacock pheasant is very low in its tropical forest on the island and the wild population is declining, it is now becoming severely endangered and should be ranked as the rarest species in the Order Galliformes in China. Our results increase the urgency of getting more morphological data to support the classification of the Hainan peacock pheasant as a distinct species and taking more conservation action immediately to protect this endangered island species.  相似文献   

17.
2005年7月至2006年12月,采用无线电遥测的方法在江西官山国家级自然保护区内对5只白颈长尾雉(Syrmaticus ellioti)的活动区域进行了跟踪监测,结合GIS技术和样方法分析其活动区域的海拔高度随季节变化的影响因素。结果表明:海拔400-600m为白颈长尾雉全年最适活动带,其主要活动区域的海拔高度呈现明显的季节变化:夏秋季最高,春季次之,冬季最低。水源是其冬季喜欢在低海拔区域活动的最主要原因;而距林缘距离、灌木数量、灌木种数、灌木盖度等与增加食物丰富度和隐蔽度相关的因子是促使它们在春季和夏秋季倾向于在高海拔区域活动的主要因素。  相似文献   

18.
Li H Q  Lian Z M  Chen C G  Wu S B 《农业工程》2009,29(5):302-306
A study on the seasonal changes in the ranging area of Brown-eared pheasant and its affecting factors was conducted in the Huanglongshan Nature Reserve, Huanglong County, Shaanxi Province, China, from March 2006 to January 2007. Forty used sites and forty random plots were selected along 8–9 transects crossing the study area. Fifteen factors related to the changes of altitude were measured in each site. The results showed that the altitude of home range of Brown-eared pheasant varied with seasons: the highest home range was found in summer, and the lowest one was found in winter, while the home range in autumn was higher than that in spring. According to the frequency of occurrences of Brown-eared pheasant in different seasons, we found that its home range occurred mainly at an altitude below 1400 m in spring, above 1500 m in summer, between 1200 m and 1500 m in autumn and below 1300 m in winter. The possible reason that Brown-eared pheasants preferred to live at lower altitude in spring was to have access to water sources and the abundance of food, correlated to the slope locations, number of trees and number of shrubs; in summer, they tended to appear at highest altitude, and the average height of shrubs, average height of grasses, sheltering class and distance to edge of woods, and human disturbance were affecting factors; in autumn, they appeared at higher altitude which was correlated with the covers of trees, shrubs and grasses, and ultimately related to the abundance of food; in winter, they lived at lowest altitude, which was correlated to the distance from the edge of woods, cover of trees and sheltering class, and ultimately related to the abundance of food and shelter.  相似文献   

19.
高黎贡山冬季白尾梢虹雉运动方式和生境偏好的初步观察   总被引:2,自引:0,他引:2  
2002及2003年1月,两次对高黎贡山大脑子白尾梢虹雉(Lophophorus sclateri)的运动方式和活动痕迹做了直接观察或样带/样方取样。该鸟滑翔是下行的主要运动方式,上行全为行走;所发现的3个夜宿地均位于坡度大、郁闭度高的近沟谷地带;冬季向低海拔迁移,与降雪有关,使得近沟谷带成为密集利用带。这样的运动和生境利用方式,显然是能耗最小化和觅食效率最大化的行为适应。  相似文献   

20.
秦岭北坡雉类种群密度和群落结构的初步研究   总被引:4,自引:0,他引:4  
本研究将秦岭北坡周至自然保护区划分为4个生态地理类型带,在以Gates截线法调查雉类种群密度的基础上,对不同生态地理类型雉类群落结构进行了研究。结果表明,秦岭北坡雉类的物种多样性与植被和海拔有一定关系,环境的稳定性对雉类物种多样性有着一定影响。调查中还发现红腹锦鸡已分布到海拔2700 m的山坡上。  相似文献   

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