滇东南一次初夏透雨的中尺度特征分析

对2005年6月1~2日滇东南地区的强降水天气过程的天气尺度影响系统、动力条件、水汽条件、稳定度及代表站指数进行了分析。结果表明,该次强降水过程是在比较有利的天气背景条件下产生的,暴雨发生前,动力条件、水汽条件和不稳定能量及代表站指数均较为有利,造成强降水的2个云团在时空尺度上具有明显的中β尺度系统特征。     

几个主要玉米自交系的配合力及聚类分析

利用16个自交系按8×8不完全双列杂交法配成64个组合,研究其株高、穗位高、生育期、穗长、穗粒数、小区籽粒产量等14个农艺性状的一般配合力(GCA)、特殊配合力(SCA)和遗传参数.结果表明:14个农艺性状的GCA和SCA均达极显著水平;控制这14个性状的基因效应中主要以加性基因效应为主,非加性基因效应较少;本试验材料中561、B603-6-1、8954、4781tl41、268、549、478C4等7个自交系GCA综合性状较优,为组配强优势杂交组合的优良自交系.根据离差平方和法进行聚类分析表明16个自交系划分成6个类群:549、8954为一类;268、478C4、冬4011、N7931、478G为一类;4781tl41、苏11为一类;561、B603-6-1为一类;WJ01、石79、1058为一类;吉1037、200H为一类.     

麻疯树遗传多样性的相关序列扩增多态性（SRAP）分析

采用相关序列扩增多态性（SRAP）分子标记对中国6省（区）及印度尼西亚共8个麻疯树Jatropha curcas种源样本进行研究,旨在阐明麻疯树种源间的遗传关系和遗传多样性。结果表明：麻疯树相关序列扩增多态性?鄄聚合酶链式反应（SRAP-PCR）最佳反应体系为：10 × PCR buffer 2 μL,DNA模板20 ng,T_aq酶16.67 nkat,Mg²⁺ 2.50 mmol·L^－1,三磷酸脱氧核苷酸（dNTP）120.00 μmol·L^－1,引物0.15 μmol·L^－1,总体积为20 μL;并从274对引物中选出具有多态性的45对引物,共检测出500条清晰的条带,其中多态性条带141条,占总条带数的28.20 %。非加权成对算术平均法（UPGMA）聚类分析及主成分分析表明,各个种源间的亲缘关系均很近,其相似系数为0.791 ~ 0.940,8个种源被聚为3类,其中印度尼西亚种源单独聚为1类,来自不同地域的7个中国种源被混聚为另外2类。图6表3参16     

Genetic Diversity of Main Inbred Indica Rice Varieties Applied in Guangdong Province as Revealed by Molecular Marker

Genetic diversity of 299 inbred indica rice varieties, including 33 introduced varieties, applied in Guangdong Province of China were assessed using 20 ILP(intron length polymorphism) and 34 SSR(simple sequence repeat) markers. Totally, 154 loci were screened for the 299 varieties, with the average number of alleles(Na), rare alleles(Nr), and polymorphism information content(PIC) scored at 3.4, 0.7and 0.32, respectively. The Nei’s genetic distance(GD) was estimated ranging from 0 to 0.7529 with an average of 0.4797. There was no significant difference of Na, Nr, PIC or GDs between the introduced and local varieties. Neighbor-joining(NJ) analysis showed that the 299 varieties failed into three main distinct groups, and the 33 introduced varieties were distributed over all the groups or subgroups. Model-based cluster analysis demonstrated that only 73(24.4%) of the 299 varieties and 7(21.2%) of the 33 introduced varieties could be distinctly classified into the three groups. Analysis of molecular variance showed that within the groups divided by NJ analysis, the genetic variations revealed by ILP, SSR and these two combined were 7.7%, 5.6% and 6.6%, and within the groups divided by region(Guangdong local and the introduced varieties), the genetic variables were 2.1%, 4.6%, 5.4%, respectively. These results suggested that the genetic diversity of the 299 inbred rice varieties in Guangdong Province was low, simultaneously relationship among varieties was poor and close in all kind of groups. Hence, it is very necessary to extend the genetic diversity during the breeding and selection practical procedure.     

澳洲坚果不同种质果皮内含物含量的研究

对28份澳洲坚果种质果皮的粗蛋白、可溶性总糖、单宁以及8种矿质元素(P、K、Ca、Mg、Zn、Cu、Fe、Mn)等内含物的含量进行了测定与研究。结果表明:澳洲坚果果皮内含物含量在不同种质之间变化较大,变异系数在15.75%~48.33%之间,变异幅度以可溶性总糖含量最大、Ca含量最小;除Fe、Cu元素外,其它6种矿质元素之间存在显著的正相关或负相关关系;聚类分析将28份种质分成4个具不同内含物含量特点的类群。     

基于曲线拟合的6种豆的傅里叶变化红外光谱研究

为能够快速的鉴别不同品种的豆,为豆类蛋白、豆类蛋白酶的提取等问题的研究提供研究依据,利用傅里叶变换红外光谱技术结合聚类分析和曲线拟合测试研究6种豆（黄豆、黑豆、蚕豆、红豆、绿豆和红小豆）54个样品的光谱。结果显示,6种豆的红外图谱相似,但在1800~1000 cm^-1范围内红外光谱的峰位、峰形及吸收强度有明显的差异。选取1800~1000 cm^-1范围的光谱图进行二阶导数处理,利用SPSS软件进行聚类分析,聚类分析正确率为100%。利用Origin 8.5软件对1700~1600 cm^-1范围的原始光谱进行曲线拟合处理,6种豆在酰胺Ⅰ带的吸收峰都由9个子峰叠加而成;其中6种豆的蛋白质二级结构中α-螺旋含量、β-转角含量、无规则卷曲结构含量和β-折叠含量不同。结果表明6种豆的蛋白质的二级结构是不同的,傅里叶变换红外光谱(FTIR)结合曲线拟合可以快速简捷地区分不同品种豆类,并能提供豆类所含蛋白质的二级结构的信息。     

甜菜种质资源叶部性状多样性及聚类分析

为进一步挖掘甜菜种质资源潜力促进甜菜品种改良及种质资源的高效利用,利用软件SPSS 22.0采用聚类分析方法对从中国甜菜种质资源中期库中筛选出的121份国内外甜菜种质资源进行了遗传多样性研究和分类。结果表明：对9个叶部形态性状进行了调查分析,其中多样性指数最高的是叶片薄厚,然后依次为叶色、叶柄长、叶面形、叶柄色、叶缘形、叶柄宽、和叶柄厚,多样性指数最低的为叶形;基于各种质间叶部性状的遗传差异,在遗传距离为12.5时将来自不同国家的121份种质资源分为4大类。第Ⅰ类群甜菜种质资源主要来自中国、美国、意大利和比利时,第Ⅱ类群甜菜种质资源主要来自俄罗斯、美国和中国,第Ⅲ类群甜菜种质资源主要来中国、美国、俄罗斯和比利时,第Ⅳ类群甜菜种质资源主要来自中国、意大利、美国、比利时和俄罗斯。聚类结果表明,不同国家的种质资源多样性较丰富,充分了解了甜菜种质资源叶部性状遗传多样性地理分布特点和种质资源群间的遗传关系,对于鉴别特异种质,挖掘优异种质材料具有现实意义。     

玉米杂交种及其农艺性状的系统聚类分析

为了研究玉米杂交种间的遗传差异以及性状间的相互关系。以 11个玉米品种的 13个农艺性状为依据, 采用系统聚类分析法计算其品种间的遗传距离及性状间的相关系数。结果表明： 11个品种共划分为 4 个类群, Ⅰ类为 QIV9、 QIV10、 QIV5、 QIV6, Ⅱ类为 QIV1、 QIV2、 QIV4, Ⅲ类为 QIV3、 QIV11、QIV7, Ⅳ类为 QIV8; 13个性状进行变量聚类分析, 被划分为 4类, 穗重、 单穗粒重、 产量、 穗行数和秃尖长聚为一类, 穗位高、 行粒数、 含水量、 轴重和穗粗聚为第二类, 穗长和百粒重聚为第三类, 株高自为一类。明确了品种间的关系亲疏以及性状间的相互关系, 可为玉米杂交种的选育及开发利用提供科学依据。     

29个苦瓜品系不同部位皂苷含量比较分析

以29个不同来源苦瓜品系为材料,进行其果实、根、茎皂苷含量测定分析及比较研究,为高含皂苷含量的苦瓜品种选育和苦瓜果实、根、茎综合利用提供依据。结果表明:不同品系苦瓜根、茎、果实的皂苷含量存在较大差异,可从中筛选高皂苷种质资源;29个苦瓜品系平均根、茎皂苷含量接近或高于果实,有望作为皂苷提取的原料加以利用;在29个苦瓜品系中,小型苦瓜的根茎或果实具有较高的皂苷含量,其中‘小型苦瓜2’根茎皂苷含量最高,‘如玉45号’果实皂苷含量最高;果实的皂苷含量具有杂种优势,可采用皂苷含量较高的亲本进行高皂苷品种选育;根据果实皂苷含量动态变化及栽培、加工的实际情况,建议加工用苦瓜在授粉后13d左右采收。     

Effects of Halide Ions on the Carbamidocyclophane Biosynthesis in Nostoc sp. CAVN2

In this study, the influence of halide ions on [7.7]paracyclophane biosynthesis in the cyanobacterium Nostoc sp. CAVN2 was investigated. In contrast to KI and KF, supplementation of the culture medium with KCl or KBr resulted not only in an increase of growth but also in an up-regulation of carbamidocyclophane production. LC-MS analysis indicated the presence of chlorinated, brominated, but also non-halogenated derivatives. In addition to 22 known cylindrocyclophanes and carbamidocyclophanes, 27 putative congeners have been detected. Nine compounds, carbamidocyclophanes M−U, were isolated, and their structural elucidation by 1D and 2D NMR experiments in combination with HRMS and ECD analysis revealed that they are brominated analogues of chlorinated carbamidocyclophanes. Quantification of the carbamidocyclophanes showed that chloride is the preferably utilized halide, but incorporation is reduced in the presence of bromide. Evaluation of the antibacterial activity of 30 [7.7]paracyclophanes and related derivatives against selected pathogenic Gram-positive and Gram-negative bacteria exhibited remarkable effects especially against methicillin- and vancomycin-resistant staphylococci and Mycobacterium tuberculosis. For deeper insights into the mechanisms of biosynthesis, the carbamidocyclophane biosynthetic gene cluster in Nostoc sp. CAVN2 was studied. The gene putatively coding for the carbamoyltransferase has been identified. Based on bioinformatic analyses, a possible biosynthetic assembly is discussed.