连续两年UV-B辐射增强对割手密叶绿素含量的影响

研究了大田栽培和自然光条件下,连续两年模拟紫外辐射(UV-B,280~315 nm)增加对92-11和93-25两个割手密无性系叶绿素含量的影响。结果表明,割手密92-11在UV-B辐射的影响下,叶绿素含量降低,而割手密93-25抗性很强,在增加了5 kJ/m2UV-B辐射下,其叶绿素含量增加。割手密叶绿素含量对UV-B辐射的响应具有种内差异。割手密92-11对紫外辐射的抗性在2004年比2003年强,而割手密93-25则相反。生育期中开花期受UV-B辐射影响最大,然后是分蘖期,伸长期抗性较强。     

Strong correlation of wild barley (Hordeum spontaneum) population structure with temperature and precipitation variation

In this study, we present the genetic analysis of a new collection of wild barley ( Hordeum spontaneum ) using 42 simple sequence repeat (SSR) markers that represent the seven chromosomes. The Barley1K (B1K) infrastructure consists of 1020 accessions collected in a hierarchical sampling mode (HSM) from 51 sites across Israel and represents the wide adaptive niche of the modern barley's ancestor. According to the genetic structure analysis, the sampled sites can be divided into seven groups, and sampled microsites located on opposing slopes or in different soil types did not show significant genetic differentiation. Although the genetic analysis indicates a simple isolation-by-distance model among the populations, examination of the genetic populations' structure with abiotic parameters in an ordination analysis revealed that the combination of elevation, mid-day temperature and rainfall explains a high proportion of the variance in the principal components analysis. Our findings demonstrate that the current populations have therefore been shaped and distinguished by non-selective forces such as migration; however, we suggest that aridity and temperature gradients played major roles as selective forces in the adaptation of wild barley in this part of the Fertile Crescent. This unique collection is a prelude for the investigation of the molecular basis underlying plant adaptation and responsiveness to harsh environments.     

云南割手密血缘F1代创新种质的因子和聚类分析

本试验对70份云南割手密血缘F1代创新种质材料8个工农艺性状进行了因子和聚类分析。因子分析中8个公因子保留前3个公因子,其累计贡献率达79.35%。第1公因子中载荷值较大的是单产、含糖量、公顷有效茎数、出苗率和分蘖率等性状;第2公因子中起主导作用的性状是茎径和株高两个产量因子;第3公因子只有11月理论蔗糖分起主导作用。以70份创新材料3个公因子的因子得分为指标,采用系统聚类中的最长距离法进行系统聚类分析。在遗传距离2.4处,参试材料被聚为十类,其中占参试材料总数的38.6%的第Ⅰ、Ⅳ、Ⅶ、Ⅷ、Ⅹ五类材料,表现高产;占参试材料82.8%的第Ⅰ、Ⅱ、Ⅳ、Ⅴ、Ⅵ、Ⅶ、Ⅸ七类材料,表现高糖,特别是其中占参试材料52.8%的Ⅰ、Ⅳ、Ⅴ、Ⅵ四类材料,11月理论蔗糖分均高于12%;占参试材料总数30%的第I、Ⅳ、Ⅶ三类材料,表现高产、高糖。这个分类结果为有针对性的利用这些创新种质材料培育高产、高糖创新亲本提供了科学依据。     

Genetic resources of wild barley in the Near East: structure, evolution and application in breeding

Genetic diversity and structure of populations of the wild progenitor of barley, Hordeum spontaneum, from three countries, Israel, Turkey and Iran, in the Near East Fertile Crescent, are compared and contrasted. The analysis is based on electrophoretically discernible allozymic variation in proteins encoded by 27 shared loci in 2125 individuals representing 52 populations of wild barley. The results indicate that: (a) H. spontaneum in the Near East Fertile Crescent is very variable genetically; (b) genetic differentiation of populations includes some clinal but primarily regional and local patterns often displaying sharp geographic differentiation over short distances; (c) the average relative genetic differentiation (G_st) was 54% within populations, 39% among populations, and 8% between the three countries; (d) allele distribution is characterized by a high proportion of unique alleles (51%), and a high proportion of common alleles that are distributed either locally or sporadically; (e) discriminant analysis by allele frequencies successfully clustered wild barley of each of the three countries (96% correct classification); (f) a substantial portion of the patterns of allozyme variation in the wild gene pool is significantly correlated with the environment and is predictable ecologically, chiefly by a combination of humidity and temperature variables; (g) natural populations of wild barley are, on the average, more variable than two composite crosses and land races of cultivated barley. The spatial patterns and environmental correlates and predictors of genetic variation of H, spontaneum in the Fertile Crescent indicate that genetic variation in wild barley populations is not only rich but at least partly adaptive and predictable by ecology and allozyme markers. Consequently, conservation and utilization programmes should optimize sampling strategies by following the ecological-genetic factors and allozyme markers as effectively predictive guidelines.     

云南割手密创新种质F_2的主成分聚类分析及其评价

云南割手密是甘蔗育种中比较宝贵的野生种质资源。对68份云南割手密F2创新种质材料的9个主要工农艺性状进行主成分分析,并以前3个主成分为基础,分别作聚类分析和二维排序图。结果表明:68份云南割手密F2创新种质的变异系数为10.57%～35.30%,11月份理论含糖量和单产的变异系数超过30%,说明11月份理论含糖量和单产性状的变异潜力较高。主成分分析结果表明,单茎重产量因子、锤度糖分因子和丛有效茎含糖量这3个主因子提供了原始性状80.8292%的信息;在欧氏距离为10.00处将68份材料分为4类,各个类群具有不同的特点,在甘蔗杂交育种上可以根据不同类群的特点加以利用;二维排序表明云割F211-50、云割F211-56、云割F211-40、云割F211-66、云割F211-77、云割F211-10、云割F211-19、云割F211-85、云割F211-45、云割F211-37、云割F211-25、云割F211-23、云割F211-18等13份材料的3个主成分构成因子协调性最好,可在育种中加以利用。     

割手密SnRK2基因家族全基因组鉴定及干旱胁迫表达分析

【目的】探究割手密SnRK2基因家族成员在干旱胁迫中的调控机制,为抗旱性甘蔗品种的选育提供侯选基因。【方法】以全基因组数据为基础从割手密中鉴定SnRK2基因,并对其进行生物信息学分析和干旱胁迫下的表达分析。【结果】在割手密基因组中共鉴定出11个SnRK2基因家族成员,命名为SsSnRK2.1-SsSnRK2.11,且这些基因不均匀地分布于8条染色体上。SnRK2蛋白的氨基酸残基数为227～580,分子质量为25 683.53～64 695.8 kD,等电点为4.62～8.94,且均为亲水性蛋白。系统发育树可将其分为3个亚组,且同亚组中的保守基序基本相似,外显子数量以7～9个为主。SsSnRK2基因家族成员的启动子中含有多种激素类和逆境胁迫响应类的作用元件。割手密SsSnRK2基因家族成员的表达具有组织特异性。所有的SsSnRK2基因均能不同程度地响应干旱胁迫。【结论】割手密SnRK2基因家族在响应干旱胁迫过程中发挥重要作用,可为割手密的抗逆性研究提供一定的理论依据。     

云南甘蔗细茎野生种82-114测交后代主要性状遗传分析

利用云南甘蔗细茎野生种82-114(简称:云割82-114)为父本,与甘蔗栽培原种、生产品种和含野生血缘F1等3类亲本进行测交.对后代锤度、茎径、株高、有效茎、蔗产量等5个主要数量性状进行方差、遗传力和配合力分析,结果表明:①组合后代锤度、茎径、株高、有效茎4个性状差异极显著;②组合后代锤度、茎径、株高、有效茎的遗传力表现较突出,均超89.0%;③3类组合中,栽培原种×云割82.114后代有效茎配合力表现明显的正效应,生产品种×云割82-114后代锤度、茎径、株高、蔗产量配合力有比较明显的正效应,舍野生血缘F1×云割82-114后代锤度、茎径、株高、有效茎、蔗产量等5个指标的配合力效应取向不明显.     

Increases in Both Acute and Chronic Temperature Potentiate Tocotrienol Concentrations in Wild Barley at ‘Evolution Canyon’

Biosynthesis of tocols (vitamin E isoforms) is linked to response to temperature in plants. ‘Evolution Canyon’, an ecogeographical microcosm extending over an average of 200 meters (range 100–400) wide area in the Carmel Mountains of northern Israel, has been suggested as a model for studying global warming. Both domestic (Hordeum vulgare) and wild (Hordeum spontaneum) barley compared with wheat, oat, corn, rice, and rye show high tocotrienol/tocopherol ratios. Therefore, we hypothesized that tocol distribution might change in response to global warming. α‐, β‐, γ‐, and δ‐tocopherol, and α‐, β‐, γ‐, and δ‐tocotrienol concentrations were measured in wild barley (H. spontaneum) seeds harvested from the xeric (African) and mesic (European) slopes of Evolution Canyon over a six‐year period from 2005–2011. Additionally, we examined seeds from areas contiguous to and distant from the part of the Canyon severely burned during the Carmel Fire of December 2010. Increased α‐tocotrienol (p<0.01) was correlated with 1) temperature increases, 2) to the hotter ‘African’ slope in contrast to the cooler ‘European’ slope, and 3) to propinquity to the fire. The study illustrates the role of α‐tocotrienol in both chronic and acute temperature adaptation in wild barley and suggests future research into thermoregulatory mechanisms in plants.     

11份割手密遗传多样性的SSR分析

利用10对多态性丰富的SSR引物,以国家甘蔗种质资源圃中保存的14份具有代表性的割手密为对照,对未收集过的云南地区11份割手密（Saccharum spontaneum L.）野生资源进行多样性分析。结果共扩增出233条DNA谱带,与对照相比,新采集材料的多态性条带为207条,其中14条为特有条带,多态性条带比率为0.89。遗传相似性系数和UPGMA聚类分析表明,新采集的材料并没有单独聚为一类,而是比较分散,在相似性系数为0.64处做切割线,参试材料可分为三个类群：第一类群主要由龙门割手密、河边村割手密和福建仙游1号组成;第二类群中包含19份材料,其中新采集的样品有上岗割手密、他拉割手密、安乐割手密、勐根割手密、芒美割手密、贺海割手密、回落割手密、里拉割手密和曼亨割手密,对照材料主要包含了云南、四川、越南、老挝、泰国地区的割手密,其共同特点是均分布在内陆地区;第三类群包括3个材料,分别是海南1号、海南92-2和广东化州割手密,其中不包含新采集的材料。而在相似性系数为0.654处作切割线又能将上述第二类群分为较细的三个亚群。由此可见,新采集的11份割手密资源具有丰富的遗传多样性,与已收集的资源相比,具有一定的差异性。说明依靠云南高山峡谷等立体气候特点,分布着遗传差异显著的割手密无性系。     

割手密2C型蛋白磷酸酶ScPP2C基因的克隆与表达分析

割手密由于具有抗病、抗虫、抗逆等潜在的有利基因,历来被用于甘蔗的抗性遗传改良。在割手密中克隆编码2C型蛋白磷酸酶(protein phosphatase 2C, PP2C)的基因,并分析其在干旱胁迫下的差异表达。本研究利用RT-PCR方法从割手密叶片中克隆得到PP2C基因的CDS全长序列,利用生物信息学在线软件对PP2C蛋白的理化性质、蛋白结构进行预测分析,并采用实时荧光定量的方法分析该基因在不同干旱处理下的差异表达。结果显示从割手密中克隆到一个全长951 bp编码316个氨基酸的2C型蛋白磷酸酶基因,命名为ScPP2C,GenBank登录号为MG322120。荧光定量分析表明,随着干旱胁迫时间的延长,其表达量呈先上调后下调的表达模式,说明该基因是干旱胁迫诱导型基因。本研究通过挖掘甘蔗野生种割手密中的抗旱新基因ScPP2C,为甘蔗野生种质资源开发利用、转基因抗旱甘蔗新品种的选育提供了参考依据。