甜瓜果肉颜色相关的分子标记开发和应用

橘色果肉是当前甜瓜育种中的重要性状之一。该研究根据橘肉甜瓜材料与非橘肉甜瓜材料,在甜瓜橘色果肉控制基因(CmOr)缺失位点(Insert/Deletion)开发出了InDel-Or1标记。利用InDel-Or1标记对28份甜瓜材料进行基因型检测。结果显示:橘肉甜瓜表现为非缺失带型或杂合带型,非橘肉材料表现为缺失带型,标记多态性与果肉颜色共分离。进一步利用InDel-Or1对2个由白色果肉与橘色果肉杂交得到的F2分离群体进行果肉颜色的鉴定,检测准确率分别为97.4%和95.3%。研究表明,InDel-Or1标记在甜瓜果肉颜色的实际鉴定中具有较高的准确性,能够大大提高育种选择的效率,缩短育种周期。     

Dissection of gene function at clonal level using mosaic analysis with double markers

MADM （Mosaic Analysis with Double Markers） technology offers a genetic approach in mice to visualize and concomitantly manipulate genetically defined cells at clonal level and single cell resolution. MADM employs Cre recombinase/loxP-dependent interchromosomal mitotic recombination to reconstitute two split marker genes--green GFP and red tdTomato -- and can label sparse clones of homozygous mutant cells in one color and wild-type cells in the other color in an otherwise unlabeled background. At present, major MADM applications include lineage tracing, single cell labeling, conditional knockouts in small populations of cells and induction of uniparental chromosome disomy to assess effects of genomic imprinting. MADM can be applied universally in the mouse with the sole limitation being the specificity of the promoter controlling Cre recombinase expression. Here I review recent developments and extensions of the MADM technique and give an overview of the major discoveries and progresses enabled by the implementation of the novel genetic MADM tools.     

More than mimicry？ Evaluating scope for flicker-fusion as a defensive strategy in coral snake mimics

Coral snakes and their mimics often have brightly colored banded patterns, generally associated with warning colora- tion or mimicry. However, such color patterns have also been hypothesized to aid snakes in escaping predators through a ＂flicker-fusion＂ effect. According to this hypothesis, banded color patterns confuse potential predators when a snake transitions from resting to moving because its bands blur together to form a different color. To produce this motion blur, a moving snake＇s bands must transition faster than the critical flicker-fusion rate at which a predator＇s photoreceptors can refresh. It is unknown if coral snakes or their mimics meet this requirement. We tested this hypothesis by measuring the movement speed and color pat- terns of two coral snake mimics, Lampropeltis triangulum campbelli and L. elapsoides, and comparing the frequency of color transitions to the photoreceptor activity of the avian eye. We found that snakes often produced a motion blur, but moving snakes created a blurring effect more often in darker conditions, such as sunrise, sunset, and nighttime when these snakes are often active. Thus, at least two species of coral snake mimics are capable of achieving flicker-fusion, indicating that their color patterns may confer an additional defense aside from mimicry     

Comparison of the potential rate of population increase of brown and green color morphs of Sitobion avenae （Homoptera： Aphididae） on barley infected and uninfected with Barley yellow dwarf virus

Life tables of brown and green color morphs of the English grain aphid, Sitobion avenae （Fabricius） reared on barley under laboratory conditions at 20 ＋ 1℃,65% ± 5% relative humidity and a photoperiod of 16 ： 8 h （L ： D） were compared. The plants were either： （i） infected with the Barley yellow dwarf virus （BYDV）; （ii） not infectedwith virus but previously infested with aphids; or （iii） healthy barley plants, which were not previously infested with aphids. Generally, both color morphs of S. avenae performedsignificantly better when fed on BYDV-infected plants than on plants that were virus free but had either not been or had been previously infested with aphids. Furthermore,when fed on BYDV-infected plants, green S. avenae developed significantly faster and had a significantly shorter reproductive period than the brown color morph. There wereno significant differences in this respect between the two color morphs ofS. avenae when they were reared on virus-free plants that either had been or not been previously infestedwith aphids. These results indicate that barley infected with BYDV is a more favorable host plant than uninfected barley for both the color morphs ofS. avenae tested, particularly the green color morph.     

千层塔植物茎叶中黄酮类物质的研究

本实验利用分光光度法对千层塔植物茎叶内的黄酮类物质进行了初步测定 ,确定了总黄酮含量提取的适宜溶剂浓度和提取的适宜时间。结果表明 ,用 6 0 %的甲醇溶剂提取 6h总黄酮含量最高。此外 ,本试验还对千层塔黄酮提取液进行了各种定性颜色反应 ,初步确定其中的黄酮类物质主要为黄酮类和黄酮醇类。     

高山植物花形态特征对花温度积累的影响

高山生态系统的低温环境不利于植物繁殖器官的发育和传粉过程,因此能改善花内或花序温度的结构对植物繁殖具有积极意义。该研究利用红外测温仪测量了高寒草甸中64种植物的花温度和叶温度以计算花温度积累,并检测了系统发育、花大小、花对称方式和花大小对花温度积累的影响。结果表明:所测量的64种植物种类,花部温度均高于叶部温度。花温度积累的系统发育信号较弱,表明物种间花温度积累的差异可能主要与不同物种对温度的需求有关。花温度积累与花大小存在显著的正相关关系,且两侧对称花的温度积累比辐射对称花更为迅速,但花对称方式和花颜色对花温度积累并没有显著的影响。该研究结果表明花温度积累在不同植物间存在很大的差异,但这些差异对植物繁殖的实际贡献和意义仍需要进一步验证。     

肺炎支原体培养镜下观察与其CCU相关性分析

建立肺炎支原体镜下观察分级标准,并与测定的CCU和实时荧光定量PCR测定结果进行关联,估算CCU。通过镜下观察肺炎支原体培养浓度和分布范围,确定其分级;采用CCU目测法和实时荧光定量PCR法测定肺炎支原体培养结果,使用等级相关分析方法 Kendall法及Spearman法进行相关性分析。结果显示,肺炎支原体镜下观察标准分为四级,与CCU及实时荧光定量PCR测定值进行关联,呈正相关。镜下观察肺炎支原体的分级越高,则测定的CCU与实时荧光定量PCR值就越高。同时发现菌液稀释104倍数时,各组实时荧光定量PCR测定值均较理想,可作为肺炎支原体培养的最佳培养稀释倍数。结果表明,在肺炎支原体培养过程中,可通过镜下观察估算其CCU,较为简便实用。     

60份国内外藜麦材料子粒的品质性状分析

研究藜麦子粒的品质性状,可以为藜麦育种、加工及消费提供参考。本研究对4份国内和56份国外藜麦材料子粒的品质性状进行了分析,结果表明60份藜麦材料子粒的千粒重、灰分、蛋白质、淀粉、脂肪、粗纤维、总黄酮和总多酚平均含量分别为4.23 g、2.28%、14.03%、57.71%、6.53%、2.46%、1.83 mg/g和1.49 mg/g。国内藜麦材料的灰分、蛋白质和总多酚平均含量较高,分别为3.47%、14.92%和1.78 mg/g;秘鲁藜麦材料的脂肪、粗纤维和总黄酮平均含量较高,分别为6.69%、2.66%和2.03 mg/g;美国藜麦材料的淀粉平均含量较高,为59.91%;玻利维亚藜麦材料的千粒重较高,为4.32 g;不同子粒颜色藜麦材料之间的品质存在差异,黑色藜麦材料的蛋白质含量较高,白色和红色藜麦材料的淀粉含量较高,红色和黑色藜麦材料的粗纤维、总黄酮和总多酚含量较高。     

鸭蛋蛋壳颜色的遗传分析

木文应用交配实验的遗传学方法,分析了蛋用鸭各种交配方式（正、反交,自交,测交）子代壳色的变异状况。试验表明,鸭蛋壳色是受一对等位基因所控制,白色蛋壳对绿色蛋壳而言,白色为隐性,绿色为显性。     

慢性应激通过减少毛囊黑色素细胞和酪氨酸酶活性导致雌性C57小鼠毛发颜色变浅

越来越多的证据表明压力可能会导致头发颜色发生变化,但其潜在机制尚不完全清楚。本研究采用雌性C57BL/6小鼠脚底电刺激结合束缚来建立慢性应激小鼠模型,并用比色法检测小鼠皮肤和B16F10黑色素瘤细胞中黑色素含量和酪氨酸酶活性;通过酶联免疫吸附实验(ELISA)测定小鼠皮肤中肿瘤坏死因子α(tumor necrosis factorα, TNF-α)、白细胞介素1β(interleukin-1β, IL-1β)和白细胞介素6 (interleukin-6, IL-6)含量;通过免疫荧光染色评估小鼠皮肤中核因子κB (nuclear factorκB, NFκB)/p65亚基的含量。结果显示:C57BL/6小鼠在慢性应激下由于皮肤中的毛囊黑色素细胞和酪氨酸酶活性降低,其毛皮颜色从暗色变为棕色。同时,慢性应激小鼠皮肤炎症反应增加,表现为皮肤中NFκB活性和TNF-α表达增加。在体外,TNF-α以剂量依赖性方式降低B16F10黑色素瘤细胞中黑色素生成和酪氨酸酶活性。以上结果表明,慢性应激通过降低雌性C57BL/6小鼠的毛囊黑色素细胞和酪氨酸酶活性来诱导皮毛颜色改变,而TNF-α可能在应激诱导的毛色改变中起重要作用。