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81.
[目的]探讨噻呋酰胺对花生白娟病的田间控制效果。[方法]以50%福美双可湿性粉剂和25%粉锈灵可湿性粉剂为对照药剂,采用小区试验研究240 g/L噻呋酰胺悬浮剂不同时期喷施对花生白娟病的防治效果及对花生的增产效果。[结果]在花生开花期、结荚初期2次分别用240 g/L噻呋酰胺悬浮剂450 ml/hm2对水喷雾,对花生白娟病的防治效果为49.90%~69.80%,初期效果与常规对照25%粉锈灵1 500 g/hm2相当,而中后期效果则好于常规对照,同时能够提高花生产量,增幅为25.41%,优于两常规对照。[结论]240g/L噻呋酰胺悬浮剂既能有效防治花生白娟病又能提高花生产量,可望用于实际生产。 相似文献
82.
Zhang Qian Lin Shanzhi Lin Yuanzhen Zhang Zhiyi Liu Haijun Zou Yening Wang Zeliang College of Biological Sciences Biotechnology Beijing Forestry University Beijing P. R. China College of Resources Environment Beijing Forestry University Beijing P. R. China 《中国林学(英文版)》2004,6(3)
The putative transgenic hybrid triploid poplars [(P. tomentosa P. bolleana) P. tomentosa] with CpTI gene have been outplanted in test field for 2 years. Although the authors previous studies have proved that they are highly resistant to 3 species of poplar-threatening insect pests and contain high content of CpTI protein in foliage, incorporation status of foreign CpTI gene in poplar genome is uncertain. In this present study, the incorporation of foreign CpTI gene in genome of 5 transgenic poplars was confirmed by PCR and Southern blotting analysis. DNA amplification showed that there were clear DNA bands of about 450bp specific to CpTI gene in transgenic lanes, while no corresponding band in non-transgenic lane was observed. Correspondingly, clear DNA hybridization signals and no signal were exhibited on film for DNA Southern blotting analysis in transgenic lanes and non-transgenic lane, respectively, which further confirmed the stable integration of foreign CpTI gene in genome of 2-year-old transgenic poplar. 相似文献
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85.
Pille F Martens A Schouls LM Peelman L Gasthuys F Schot CS De Baere C Desmet P Vandenberghe F 《Research in veterinary science》2004,77(3):189-195
Standard culturing techniques are often unrewarding in confirming diagnosis of synovial infection in the equine patient. Several human studies report the use of sensitive polymerase chain reaction (PCR) techniques for the detection of bacterial involvement in acute synovitis. However, successful extraction of bacterial DNA directly from clinical samples from horses without prior culture has not been reported yet. The goal of this study was to develop a sensitive and reliable method for molecular detection and identification of bacterial species in synovial fluid from horses with infectious synovitis. Synovial fluid samples from 6 horses with culture confirmed synovial infection were used for broad range 16S rRNA gene PCR. Synovial aspirates of 2 healthy horses were used as negative controls. Following extraction and purification of synovial fluid DNA, all samples were processed by touchdown PCR. Amplicons were detected by reverse line blot hybridisation and visualised with chemiluminescence. Pathogen-specific detection of 16S rRNA gene sequences was successful in all 6 synovial fluid samples. No bacterial DNA was detected in the aspirates from the negative control horses using touchdown PCR followed by 25 additional cycles of amplification. The identity of the pathogens was confirmed by DNA sequencing of the amplicons. It can be concluded that broad range 16S rRNA gene PCR followed by reverse line blot hybridisation is a promising technique for detection of bacterial DNA in synovial fluid samples. Further research should aim at the detection of bacterial DNA in synovial fluid samples suspected of infection but having negative culture results. When the 16S PCR proves to be reliable and more sensitive than standard culturing techniques, it may become a powerful tool in the diagnosis of synovial infection. 相似文献
86.
Relationships between Longevity and Linear Type Traits in Holstein Cattle Population of Southern Africa 总被引:1,自引:0,他引:1
Relationships between longevity and linear type traits were estimated using data on 34,201 cows with lifetime information and linear type scores. The longevity trait considered was the number of lactations initiated and the linear type traits were rump height, body depth, angularity, rear udder height, fore udder attachment, udder depth, fore teat placement and fore teat length. Fixed effects included in the models were herd year, season of calving and herd-date of classification-classifier and days in milk. Age at first calving and age at classification were included as linear and quadratic covariates. Heritability estimates were low for longevity and moderate for most type traits except rump height and fore teat length. All the phenotypic correlations between longevity and the linear type traits were slightly positive (0.01 to 0.09) except the relationships with rump height and fore teat length which were -0.01 and -0.02, respectively. Genetic correlations between longevity and udder traits as well as angularity were moderate to high and positive (0.22 to 0.48). The only notable negative genetic correlations were longevity with body depth and fore teat length (-0.15 and -0.07, respectively). The genetic correlations suggest that selection for udder traits and angularity should improve longevity in the Holstein cattle population. 相似文献
87.
以实验生态学和生态工程相结合的措施,按照人为设计理论和生态恢复的一般程序,在中国南方亚热带丘陵地区研究截叶胡枝子(Lespedeza cuneata)草地和宽叶雀稗(Paspalum wettsteinii)草地植被的重建,并探讨了这一生态恢复模式在恢复初期的生态学过程和规律.主要结果如下: 相似文献
88.
介绍一种测定离层纤维素酶活性的新方法—凝胶扩散-组织印迹法.给出了该测定方法的基本原理、流程、步骤及计算方法,并以此方法测定了龙眼果实脱落过程中果柄离层纤维素酶活性的变化.结果表明该方法需要材料少,灵敏度高,纤维素酶活性最低可检出2×10-6U. 相似文献
89.
通过对川南传统古镇罗城镇进行现场调研,对古镇现有资源与现状进行了综合评述。介绍了罗城古镇的基本情况和保护价值,分析了古镇的保护现状与存在问题,认为古镇风貌与环境破坏严重、古镇建筑毁坏严重、缺乏保护资金,并且关于古镇保护的宣传不到位。针对以上问题,就古镇的保护与发展提出了建设性意见,重点在于进行合理的保护与规划,调整古镇功能结构,重视保留古镇的完整性和整体性,加强和提高居民的保护意识。以期促进川南传统古镇的保护与可持续发展。 相似文献
90.
对陕南三市的区域定位状况、经济发展现状、政策机遇进行了分析,确定了该区域的战略定位;进一步讨论了利用当前中央到地方的各项利于贫困地区的政策,融入整个西部大发展的大局中,并提出了发展模式与建议。 相似文献