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961.
随着现代杂交稻育种的发展,利用表型进行品种特异性鉴定、品种真实性鉴定以及种子纯度测试的方法表现出诸多局限性,已经不再适合现代育种的进程.本研究利用水稻基因组插入缺失(insertion-deletion,InDel)位点开发了9个InDel标记用于鉴定生产中常用的29份杂交稻骨干亲本.利用标记电泳图谱做了供试材料的聚类分析,在遗传相似系数0.55左右可将所有供试材料分为5个类群,另外根据不同的亲缘关系和来源地区,又可以将供试材料分为9个亚群.最后利用品种鉴别标记和生长测试两种方法对一份杂交稻种子'广两优476'纯度进行了检测,结果表明两者基本一致.因此,分子标记可以有效应用于现代育种的各个环节,从而加快新品种选育.本研究结果将为水稻育种、新品种审定、品种鉴定以及种子生产提供有益的帮助. 相似文献
962.
不同行数植物篱对红枫湖坡耕地养分的拦截效应 总被引:2,自引:0,他引:2
为选出控制红枫湖坡耕地水土流失效果较好的植物篱带宽,对比了由香根草和灰毛豆混合建设(1∶1行间混交,>2行为行间交互混交)的不同行数的植物篱(每个处理小区种植3带植物篱,分别设每带2行,每带4行,每带6行,自上而下每带分别2、4、6行4个植物篱处理及对照共5个处理)对地表径流量、泥沙量及地表径流中水溶解态全氮、全磷、全钾、铵态氮和泥沙中的固体态的全磷、全钾的影响。结果表明:各植物篱处理的各项指标都小于对照处理;方差分析结果及F测验证明,处理间存在显著差异(P<0.05)。多重比较结果表明:1)除每带2行植物篱外,其他植物篱处理都相对于对照对养分元素具有显著的拦截作用。2)每带4行处理和自上而下各带分别2、4、6行植物篱处理与每带2行处理无显著差异;每带6行处理显著小于每带2行植物篱处理。3)除泥沙所含的磷、钾元素外,每带6行与自上而下分别2、4、6行植物篱无显著差异,每带6行的各个指标都与每带4行无显著差异。综合试验结果和实际应用要求得出,每带4行是本试验所涉及的植物篱行数中的最佳行数,其次自上而下每带分别2、4、6行的种植方式也较好。 相似文献
963.
Shen HW Cao MJ Cai QF Ruan MM Mao HY Su WJ Liu GM 《Journal of agricultural and food chemistry》2012,60(9):2190-2199
Arginine kinase (AK) is an important enzyme participating in energy metabolism in invertebrates, but, to date, there have been no reports that AK from octopus is an allergen. In this study, octopus AK was purified, and its molecular biological, immunological, and physicochemical characterizations were analyzed. The results showed that octopus AK was purified and confirmed by mass spectrometry for the first time, and its molecular mass was 38 kDa. The full-length gene sequence of octopus AK encompassed 1209 bp and was predicted to encode a protein with 348 amino acid residues. The homology of octopus AK and crustacean AK was about 54%, but the similarity between their three-dimensional structures was high. Octopus AK could react with mouse anti-shrimp AK and rabbit anti-crab AK polyclonal antibody singly. Octopus AK could also react with specific IgE of the sera from octopus-allergic patients effectively, whereas crab AK could inhibit the reaction between them. Finally, the IgE-binding activity of octopus AK could be reduced in the processes of thermal or acid-alkali treatment. In summary, AK was identified as a novel allergen in octopus, which had a sensitizing ability similar to that of crustacean AK. This is significant in allergy diagnosis and the treatment of octopus-allergic disorders. 相似文献
964.
Cheng F Sheng J Cai T Jin J Liu W Lin Y Du Y Zhang M Shen L 《Journal of agricultural and food chemistry》2012,60(10):2546-2553
A metagenomic library of China Holstein cow rumen microbes was constructed and screened for novel gene cluster. A novel feruloyl esterase (FAE) gene was identified with a length of 789 bp and encoded a protein displaying 56% identity to known esterase sequences. The gene was functionally expressed in Escherichia coli BL21 (DE3), and the total molecular weight of the recombined protein was 32.4 kDa. The purified enzyme showed a broad specificity against the four methyl esters of hydroxycinnamic acids and high activity (259.5 U/mg) to methyl ferulate at optimum conditions (pH 8.0, 40 °C). High thermal and pH stability were also observed. Moreover, the enzyme showed broad resistance to proteases. FAE-SH1 can enhance the release of ferulic acid from wheat straw with cellulase, β-1,4-endoxylanase, β-1,3-glucanase, and pectase. These features suggest FAE-SH1 as a good candidate to enhance biomass degradation and improve the health effects of food and forage. 相似文献
965.
Ying Yan Dandan Lu Hao Zhou Haiping Hou Ting Zhang Laiming Wu Lankun Cai 《Water, air, and soil pollution》2012,223(3):1275-1280
A polyaniline-modified quartz crystal microbalance (QCM) sensor was obtained through immobilizing the polyaniline film on
the silver electrode surface of quartz crystal resonator by an electrochemical method. The sensor was studied for detecting
the formic acid gas of different concentrations, and the results showed that the resonant frequency of QCM decreased quickly
in the beginning and tended to be constant in the end when exposed to formic acid gas. The frequency shifts decreased faster
as the concentration of formic acid gas increased. And the frequency shifts of the QCM sensors were found to be linearly related
to the concentration of formic acid gas, which might be used to estimate the concentration level of the formic acid gas within
the range of experimental concentrations. The result of on-line monitoring test fully indicated that the QCM sensor responded
effectively to the increasing concentration of formic acid and had important practical significance and broad application
prospect in real-time detection of antique conservation environment in the museum. 相似文献
966.
Hongyan?Yu Weixin?DingEmail author Jiafa?Luo Ruilin?Geng Anwar?Ghani Zucong?Cai 《Biology and Fertility of Soils》2012,48(3):325-336
The study examined the influence of compost and mineral fertilizer application on the content and stability of soil organic
carbon (SOC). Soil samples collected from a long-term field experiment were separated into macroaggregate, microaggregate,
and silt + clay fractions by wet-sieving. The experiment involved seven treatments: compost, half-compost N plus half-fertilizer
N, fertilizer NPK, fertilizer NP, fertilizer NK, fertilizer PK, and control. The 18-year application of compost increased
SOC by 70.7–121.7%, and mineral fertilizer increased by 5.4–25.5%, with no significant difference between control soil and
initial soil. The C mineralization rate (rate per unit dry mass) in microaggregates was 1.52–2.87 mg C kg−1 day−1, significantly lower than in macroaggregate and silt + clay fractions (P < 0.05). Specific C mineralization rate (rate per unit SOC) in silt + clay fraction amounted to 0.48–0.87 mg C g−1 SOC day−1 and was higher than in macroaggregates and microaggregates. Our data indicate that SOC in microaggregates is more stable
than in macroaggregate and silt + clay fractions. Compost and mineral fertilizer application increased C mineralization rate
in all aggregates compared with control. However, compost application significantly decreased specific C mineralization rate
in microaggregate and silt + clay fractions by 2.6–28.2% and 21.9–25.0%, respectively (P < 0.05). By contrast, fertilizer NPK application did not affect specific C mineralization rate in microaggregates but significantly
increased that in silt + clay fractions. Carbon sequestration in compost-amended soil was therefore due to improving SOC stability
in microaggregate and silt + clay fractions. In contrast, fertilizer NPK application enhanced SOC with low stability in macroaggregate
and silt + clay fractions. 相似文献
967.
盐渍土时空变化信息的图谱可视化分析 总被引:5,自引:2,他引:3
针对盐渍土动态变化监测中,无法实现变化信息的定位可视化表达问题,该文应用地学信息图谱的分析理念,提出了表达盐渍土类型变化的时空复合单元,探讨了盐渍土时空变化信息的图谱可视化表达方法。以盐渍化比较严重的银川平原为研究区,利用2000、2004和2009年3a的卫星遥感图像,进行了土壤盐渍化遥感制图,在GIS技术支持下,获取了2000-2004年、2004-2009年2个时段的盐渍土时空变化信息图谱,实现了盐渍土时空变化信息的可视化表达。为定位分析盐渍土演化的驱动机制提供了一种新的方法。 相似文献
968.
胺基化磁性壳聚糖微球对苹果渣多酚的吸附条件优化 总被引:2,自引:0,他引:2
为分离苹果渣中的多酚物质,研究壳聚糖磁性材料对多酚物质提取的影响。采用化学共沉淀法制得Fe3O4磁核,反相悬浮交联法制得磁性壳聚糖微球,并进行胺基化改性;利用扫描电镜、激光粒度仪对微球进行表征。采用单因素试验和响应曲面法对磁性微球吸附分离苹果渣多酚的吸附条件进行了工艺优化。结果表明:胺基化磁性壳聚糖微球吸附苹果渣多酚工艺参数对多酚吸附率有显著影响,因素影响主次顺序为微球用量>摇床转速>吸附温度;胺基化磁性壳聚糖微球吸附苹果渣多酚的工艺参数为:微球用量0.25g/mL,吸附温度45℃,摇床转速127r/min,吸附率可达81.58%。壳聚糖与Fe3O4磁性物质相结合,对多酚物质具有良好的吸附性能,可以对多酚物质进行快速分离,解析后多酚得率可达78.73%。研究结果为磁性材料吸附分离多酚类物质提供了理论参考。 相似文献
969.
利用地下水模型模拟分析灌区适宜井渠灌水比例 总被引:7,自引:6,他引:1
为了获取泾惠渠灌区适宜井渠灌水比例,科学合理地确定农业节水方案,该文综合应用ArcGIS和PMWIN地下水模拟软件建立了灌区的地下水分布模拟模型,根据灌区历年农业用水实际情况设定了10种灌溉情景模拟灌区地下水位的变化趋势,通过地下水模型分析研究了灌区井渠灌水比例。利用VB程序语言改写EVT蒸发蒸腾子程序包,使其能模拟非线性蒸发,潜水蒸发量计算精度得到较大改进。研究表明:1)渠首有效灌溉引水量在3.7~4.1亿m3,井渠灌水比例控制在0.35~0.55,基本可以保持灌区地下水采补平衡;2)渠首有效灌溉引水量在1.5~2.0亿m3,井渠灌水比例控制在0.5~0.7,也能实现灌区地下水采补平衡;3)目前井渠灌水比例在0.9~1.2,已引起灌区地下水超采。建议井渠灌水比例控制在0.5~0.7,加大农业节水力度、增加水价财政补贴、进行地下水人工调蓄,实现灌区水资源高效持续利用。 相似文献
970.
面向机器人采摘的荔枝果梗力学特性 总被引:3,自引:3,他引:0
为了给荔枝采摘机器人夹持与切割器的设计和控制提供依据,对荔枝果梗分别进行了切割性能和夹持性能的影响因素试验以及弯曲试验。试验结果表明:峰值切割力和切割强度随着切割速度增加而减小,随着切割角度的减少而减少,凹刃和凸刃的峰值切割力和切割强度都比平刃小;除果梗直径因素外对峰值切割力和切割强度影响显著的因素均依次为切割角度、刃口形式和切割速度;切割角度每减少1,峰值切割力和切割强度分别减少4.45N和0.16MPa;相比平刃的峰值切割力和切割强度,凸刃分别减少166.90N和2.11MPa,而凹刃分别减少167.39N和4.21MPa。随着夹持力增加,荔枝果梗与夹持物间摩擦力增加,夹持物为橡胶时,摩擦力最大,夹持力对摩擦力的影响大于夹持材料;试验范围内,最大摩擦力为44.54N。荔枝果梗具有较强的抵抗变形的能力,平均弹性模量为867.15MPa;试验范围内,最大弯曲力的平均值为118.95N,抗弯强度的平均值为56.03MPa。该研究为荔枝采摘机器人的夹持与切割机构的优化设计和控制提供了理论依据。 相似文献