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961.
Ming-Xia Zhao Hai-Yan Sun Rui-Rui Ji Xiao-Hui Hu Jiong-Ming Sui Li-Xian Qiao Jing Chen Jing-Shan Wang 《Euphytica》2013,193(1):89-99
To expand the salt-tolerant gene resources of peanut, we conducted in vitro mutagenesis with pingyangmycin (PYM) as the mutagen and directed screening with medium containing NaCl. After embryonic leaflets from mature peanut seeds (variety Huayu 22) were cultured on somatic embryogenesis-induction medium containing 4 mg/L PYM for 4 weeks, the surviving somatic embryos were sequentially transferred to a germination medium containing 15 and then 20 g/L NaCl. The 30 NaCl-tolerant plantlets obtained were grafted and transplanted in the field in 2011, and the mature seeds of 26 regenerated plants were harvested. In 2012, all seeds from each plant were sown in the field. The offspring (M2 generation) of 23 of 26 NaCl-tolerant, regenerated plants differed from their mutagenic parent in vigor, growth habit, flowering habit, pod shape, and seed coat color, and they also exhibited trait segregation from the same NaCl-tolerant, regenerated plant. In a germination test with a 0.7 % NaCl solution and the M3-generation seeds from 18 of the NaCl-tolerant, regenerated plants, the germination rate was substantially higher for the seeds from 6 plants than for seeds from the mutagenic parent (Huayu 22). To determine whether the changes in plant traits might be associated with gene mutations, DNA polymorphisms between the mutagenic parent and 19 M3 generation individuals from different NaCl-tolerant, regenerated plants were analyzed with 39 pairs of SSR primers, and all mutants differed from the mutagenic parent in >2 loci. The results indicate that the use of PYM-based mutagenesis in combination with directed in vitro screening with NaCl is effective for creating and identifying salt-tolerant mutants of peanut. 相似文献
962.
常州市城市内河常见鱼类资源及保护的研究 总被引:1,自引:1,他引:0
为了更好的评价常州城市内河治理后的生态环境。于2012年8—12月连续3次对江苏省常州市新北区运北水系的三井河、柴支浜河、北塘河、通济河、澡港河进行了常见鱼类群落调查。调查共捕获鱼类331尾、3523.55 g,隶属3目3科11属12种。鲤形目中的鲫(餐)、贝氏(餐)为优势种(IRI≥1000),似鳊、麦穗、乌鳢等为常见种(IRI≥100),合鳃目中黄鳝等为稀有种(IRI≤100)。Margalef丰富度指数以4#易买得最高,达到1.924,而1#塘北桥,7#勤丰桥为较高,以11#通济河西为最低;Shannon-Wiener多样性指数以7#勤丰桥最高,达到1.431,而10#三井河桥,1#塘北桥为较高,以13#通济河东为最低;Pielou's Evenness Index均匀度指数以3#三井桥最高,达到0.978,而10#三井河桥,1#塘北桥为较高,以13#通济河东为最低;多样性指数和均匀度指数与高锰酸盐指数、BOD5、石油类、总氮、氨氮等环境因子呈显著负相关关系,多样性指数和发光细菌急性毒性及丰富度指数呈显著正相关关系。鱼类种类调查结果可为常州市运河鱼类资源保护和利用提供参考,同时也为生态环境的修复进展提供有力证明。 相似文献
963.
为了研究Tα1的免疫增强效果,以120只1日龄SPF鸡作为试验对象,联合应用表达Tα1的重组质粒pcDNA-Tα1和H5亚型禽流感灭活疫苗,观察不同剂量Tα1对免疫鸡只血清HI抗体水平、免疫器官指数以及抗病毒作用的影响。结果表明:Tα1各剂量处理组在鸡只免疫后7~21 d对HI抗体水平有轻微抑制,28 d与正常免疫组达同一水平;鸡只的法氏囊、胸腺和脾脏免疫器官指数均显著增加(P<0.05),尤以低剂量组(50μg/只)效果最佳;攻毒后,Tα1各剂量组对鸡只的保护率均为100%。可见,Tα1对禽流感H5N1疫苗有较强的免疫促进作用,且呈现一定的剂量关系,以低剂量(50μg/只)的免疫增强效果最为理想。 相似文献
964.
965.
2012年夏、秋季,对安徽省长江以南地区高速公路绿化景观发生的主要虫害进行了调查研究,主要有刺吸类、蛀干类和食叶类,其中包括安徽省首次发现的缨鞘宽腹叶蜂共计38种,隶属5目19科35属。这些绿化树种害虫严重威胁高速公路绿化的安全与观赏效果,发生严重时可致死植株。通过调查,总结出了主要害虫的发生规律和防治方法,以供高速公路绿化景观养护参考。 相似文献
966.
Liang Chen Ling-Ping Zhao Chun-Lei Ma Ya-Li Zhang Zhen Liu Xiao-Yan Qiao 《The Journal of Horticultural Science and Biotechnology》2013,88(5):476-482
SummaryThe expressed sequence tag (EST) technique provides a quick, efficient, and inexpensive route for gene cloning, gene expression profiling and regulation analysis, genome mapping, and functional annotation of genome sequences. Although an important cash crop, research on the molecular biology of tea (Camellia sinensis) started later and progressed more slowly than similar advances in major cereal crops and woody species. Most recently, progress has been made on the molecular biology of tea based on the strategies of EST sequencing and annotation. Advances have included the elucidation of gene expression profiling, the establishment and use of cDNA microarrays, data mining for EST-SSR (simple sequence repeat; microsatellite) and STR (short tandem repeat) loci, and cloning and expression analysis of genes involved in secondary metabolism, and stress defense.All these advances have contributed to a better understanding of the molecular mechanisms underlying growth, development, metabolism, and responses to the environment in tea plants, as well as to the promotion of molecular biology research in tea. New high-throughput sequencing technology will further accelerate genome sequencing of this species in the future. 相似文献
967.
J. Fang C. Song Y. Zheng Y. Qiao Z. Zhang Q. Dong 《The Journal of Horticultural Science and Biotechnology》2013,88(6):833-839
SummaryClementines are an important group of citrus cultivars. However, little is known about their genetic diversity. In this study, methylation-sensitive amplification polymorphism (MSAP), based on the application of isoschizomers (Hpa II and Msp I), was used to analyse cytosine methylation patterns in 18 Clementine cultivars. Conventional AFLP analysis showed only two polymorphic bands out of a total of 1,822 AFLP bands generated using 28 primer pairs. Three types of bands were generated by MSAP using 27 pairs of primers. Type I were present in both Eco RI + Hpa II and Eco RI + Msp I gels. Type II or Type III were present only in Eco RI + Hpa II, or Eco RI + Msp I gels, respectively. The total numbers of these three Types of bands were 1,377, 98, and 93, respectively. Among these three Types of bands, the number of polymorphic bands were 76 (5.5%), 30 (30.6%), and 15 (16.1%), respectively. Of these, non-reproducible polymorphic bands in duplicated samples were 27 (35.5%), 18 (60.0%), and 9 (60.0%). Each Clementine cultivar had specific and relatively fixed methylated CCGG sites, which could be revealed from their specific MSAP patterns. The reproducible polymorphic bands in duplicated samples were used to analyse the extent of variation in methylation. The diversity of the cultivars revealed by the resulting dendrogram suggests that DNA methylation may be one of the main factors accounting for the difference in agronomic traits between Clementine cultivars. 相似文献
968.
969.
970.
为分析铝合金结构拱形ETFE(乙烯-四氟乙烯热塑性聚合物)膜屋面的抗风性能,提高其设计的安全性,该文根据单轴拉伸试验数据,确定了ETFE薄膜材料的力学参数和应力应变关系;基于几何非线性有限元理论,推导了膜单元的基本方程;利用大型通用有限元软件ANSYS,采用支座提升法对骨架式拱形ETFE屋面进行了找形分析,建立了用于荷载分析的计算模型;对拱形ETFE屋面在风荷载工况下进行了算例分析,计算了膜面主应力分布和变形特征;分析了不同膜面预应力水平对承载性的影响。分析结果表明,风荷载主要影响ETFE膜屋面第一主应力的分布,适当增加膜面预应力可以显著提高其整体刚度和承载力。研究结论为铝合金温室拱形ETFE屋面的抗风计算分析和施工提供了参考。 相似文献