基于线粒体Cytb序列的3个宽体金线蛭群体遗传多样性分析

对江苏省扬州高邮、苏州张家港、泰州海陵3个地区宽体金线蛭自然群体的线粒体Cytb基因全序列进行了测定和分析。结果显示:宽体金线蛭Cytb基因全长1 146 bp,样本的A、G、T、C平均含量分别为27.57%、15.77%、43.49%、13.17%,A+T含量(71.06%)明显高于G+C含量(28.94%)。在77个宽体金线蛭样本中,共检测到96个多态位点,其中有58个简约信息位点,获得47个单倍型,共享单倍型数目1个。3个宽体金线蛭群体的平均单倍型多样性、核苷酸多样性、平均核苷酸差异数分别为0.9781、0.0133、15.20,其中泰州海陵群体的单倍型多样度(0.987 7)和核苷酸多样度(0.013 1)最高。3个群体间的遗传分化指数F_(st)为0.065 1～0.175 6,且差异显著(P0.05),不同群体间存在一定的遗传分化。分子方差分析(AMOVA)表明,11.13%的变异来自群体间,88.87%的变异来自群体内。用邻接法构建的单倍型系统发育进化树显示,不同地理群体的个体呈交错分布,没有形成明显的地理谱系。中性检验和核酸不配对分布结果表明,3个宽体金线蛭野生群体总体大小保持相对稳定,没有发生明显的种群扩张。     

青海栽培黄管秦艽的叶绿体DNA psbA-trnH核苷酸变异和遗传分析

[目的]研究青海栽培黄管秦艽（Gentiana officinalis H.Smith）的遗传多样性,对黄管秦艽遗传分化进行分析,为其品种选育提供建议。[方法]应用叶绿体DNApsbA-trnH序列对青海地区栽培黄管秦艽6个居群进行遗传多样性分析。[结果]共发现10种不同的单倍型,通过单倍型序列间比对,发现了7个变异位点,黄管秦艽具有较高的遗传多样性（h=0.771）,单倍型多态性水平（h）为0.563~0.857,核苷酸多态性水平（π）为0.002 43~0.006 31。居群遗传分化系数Gst为0.196 0,基因流Nm值为2.05,80.40%遗传变异主要存在于居群内。[结论]青海栽培黄管秦艽的种质遗传多样性较高,有利于培育高品质的药材。     

基于Rag1基因序列的黄河高原鳅群体遗传结构分析

【目的】明确不同水域黄河高原鳅群体免疫基因多样性水平和遗传组成,为黄河高原鳅自然种质资源现状的评估、保护及合理开发提供理论依据。【方法】采集黄河中上游不同河段的黄河高原鳅自然群体［青海循化（XH）群体、青海大通（DT）群体及甘肃景泰（JT）群体］样品,基于重组激活基因（Rag1）序列对不同黄河高原鳅群体的遗传多样性水平和遗传组成差异进行研究。【结果】在不同黄河高原鳅群体的Rag1基因序列中共检测到8个单倍型（H1~H8）,其中有5个单倍型（H1、H2、H3、H4和H6）在2个以上的群体间相互共享,尤其是单倍型H1、H4和H6在所有群体中均有分布。黄河高原鳅总群体的单倍型多态性为0.742,核苷酸多态性为0.003,在3个黄河高原鳅群体中共检测到28个多态位点。不同黄河高原鳅种群间的单倍型多态性范围在0.575~0.872,核苷酸多态性范围在0.002~0.003。XH群体与JT群体间的遗传分化系数（F_st）为0.037,XH群体与DT群体间的F_st为-0.041,JT群体与DT群体的F_st为-0.022;不同黄河高原鳅群体的分子遗传变异主要发生在群体内（占99.56%）。单倍型网络结构图及NJ聚类树和ML聚类树均显示,不同黄河高原鳅自然种群个体相互混合在一起,未按照采样河段地理位置形成明显的聚类结构,即黄河高原鳅不同单倍型间呈现混合的分布格局。【结论】黄河高原鳅群体遗传多样性水平中等,不同自然群体间的遗传多样性水平存在一定差异,但并未检测到显著的遗传差异,建议在野外进行管理和保护时仍可视为一个整体。     

Population genetic structure of Sitobion miscanthi in China

The wheat aphid, Sitobion miscanthi, is one of the most destructive pests of wheat plants in the temperate regions of China. Little is known about the genetic structure evolution of the different geographic populations of S. miscanthi with its migration. In this study, we investigated the population genetic structure and demographic history of S. miscanthi by analysing 18 geographical populations across China using one mitochondrial gene, COI; one nuclear gene, EF-1α; and two endosymbiont Buchnera genes, gnd and trpA. Analysis of data from the various groups showed high haplotype diversity and low nucleotide variation. SAMOVA analysis did not find a correlation between genetic distance and geographic distance. However, areas with high population diversity exhibited high haplotype diversity. Therefore, we speculate that there are two main natural migration pathways of S. miscanthi in China. One is from Yunnan to the Sichuan Basin, and the other is from Wuhan, Xinyang and Jiaodong Peninsula areas to the northwest. Based on this hypothesis, we inferred that these aphid populations appear first in the southwestern and southern regions and spread to the north with the help of the southeastern and southwestern monsoons, which occur in spring and summer. In autumn, the aphids spread southward with the northeastern and northwestern monsoons.     

青海五裂茶藨子叶绿体DNA psbA-trnH序列的遗传变异研究

采集青海不同地理居群五裂茶藨子植物样品,采用改良CTAB法提取五裂茶藨子总DNA。运用分子生物学技术分析青海不同地理居群五裂茶藨子的遗传多样性。结果表明:青海不同地理居群五裂茶藨子psbA-trnH序列可分为11种单倍型,存在38个变异位点,具有较高的遗传多样性（h=0.684 1）,单倍型多态性水平（h）为0.464 3～0.892 9,核苷酸多态性水平（p）为0.005 90～0.023 33。居群遗传分化系数G_st为0.042,基因流值N_m为0.014 98。     

安徽淮河水系黄鳝群体遗传多样性及其遗传结构

利用线粒体Cyt b基因全序列(1138 bp)对安徽淮河水系黄鳝6个地理群体(阜南Fn、颍上Ys、平圩Pw、怀远Hy、凤阳Fy、明光Mg)165个样品进行遗传多样性和遗传结构分析。共检测到变异位点74个、单倍型25个,平均A+T含量(54.8%)显著大于G+C(45.2%)含量。平均单倍型多样性和平均核苷酸多样性分别为0.787、0.01882。各群体的遗传分化指数FST为0.01933~0.81352、基因流Nm为0.11461~26.36650,分子方差分析(AMOVA)显示44.1%的变异来自群体间,表明淮河水系黄鳝地理群体间存在较高程度的遗传分化。单倍型系统进化树和进化网络图揭示安徽淮河黄鳝6个群体的个体组成2个遗传差异明显的谱系。错配分布和中性检验结果表明安徽淮河黄鳝群体历史上较为稳定,无明显群体扩张。     

灰葡萄孢蚕豆分离物的遗传多样性

【目的】灰葡萄孢是引起蚕豆赤斑病、花腐病和荚腐病的重要病原菌,其为包含两个称作类群I和类群II的复合种,具有高度的遗传变异。然而,危害蚕豆的灰葡萄孢复合种地位及遗传特征尚未被研究。论文旨在对中国6个不同地理来源蚕豆灰葡萄孢复合种的地位进行鉴定,研究其遗传多样性及群体间的遗传分化,为探明病害流行规律及制定防治策略提供依据。【方法】在PDA培养基上观察分离物形态特征。用Flipper和Boty特异性引物检测分离物的转座子基因型。葡萄孢复合种所属类群通过Bc-hch基因的PCR扩增酶切多态性鉴定,SSR标记分析解析其遗传多样性和遗传分化。【结果】100个灰葡萄孢分离物均为灰葡萄孢类群II,共产生菌核型、菌丝型和分生孢子型3种类型菌落形态,其中76个分离物为菌核型。92个分离物为转座子基因型,分别含有Boty、Flipper和Boty+Flipper,其中仅含Boty分离物最多,占检测分离物的61.0%。江苏分离物只含有单一Flipper,重庆、四川、甘肃和河北分离物只含有单一Boty。基于SSR分析,100个分离物被鉴定为92个多位点基因型,6个群体的平均基因多样性指数和平均基因型多样性指数分别为0.5140和0.9982;分子方差分析（AMOVA）发现群体内遗传变异占总变异的86.70%。标准关联指数rD值范围为0.0312-0.1261,平均0.0491;遗传固定指数（FST）在0.0085-0.2650,平均为0.1330。UPGMA聚类将100个分离物划分为10个遗传组,大部分遗传组包含不同地理来源的分离物。贝叶斯（Bayesian）推理分析将92个多位点基因型分为两个遗传类群,其中重庆和四川群体聚为一类,青海群体单独聚为一类,而江苏、河北和甘肃群体由两个不同遗传类群组成。【结论】源于蚕豆的灰葡萄孢群体由灰葡萄孢类群II组成,分离物的菌落形态以菌核型为主,绝大多数分离物为转座子基因型,但转座子基因型分布明显存在地域差异。调查的6个群体都具有高水平的遗传多样性,遗传变异主要来源于群体内,生殖方式以有性繁殖为主,大部分群体间存在中等到大的遗传分化。     

基于线粒体CO Ⅰ 基因序列的红螯螯虾养殖群体遗传结构分析

红螯螯虾原产于澳大利亚,是一种具有优良养殖前景的淡水虾类。基于线粒体COⅠ基因序列,对中国5个养殖群体的遗传多样性和结构进行评估,旨在为红螯螯虾的科学引种、良种选育和种质资源保护提供基础数据。结果显示,红螯螯虾线粒体COⅠ区全序列长1 534 bp,包含24个变异位点,占分析位点的1.6%,变异位点中含有22个简约信息位点,平均转换与颠换的比值为6.14,序列中(A+T)的含量(58.7%)明显高于(G+C)的含量(41.3%),在143个个体中定义了35种单倍型,来自浙江、海南和台湾的养殖群体具有较多的共享单倍型(COⅠ-01、COⅠ-02和COⅠ-03),这3种单倍型同时也是优势单倍型。来自江苏的养殖群体的单倍型多样性最低(0.739),来自安徽的养殖群体的单倍型多样性最高(0.881)。全部样本的单倍型多样性指数为0.896,核苷酸多样性指数为0.004 65。5个养殖群体间的遗传距离为0.002 63~0.006 81,其中,来自浙江与海南的养殖群体的遗传距离最近,来自海南与安徽的养殖群体的遗传距离最远。5个养殖群体间的遗传分化系数为0.342 1(P<0.01),说明5个养殖群体间存在一定程度的遗传分化。综上,5个红螯螯虾养殖群体的遗传多样性存在差异,群体间存在着一定的基因交流。研究结果可为红螯鳌虾种质资源的合理开发利用提供分子生物学依据。     

Dispersal routes of Cercospora zeina causing maize gray leaf spot in China

The gray leaf spot caused by Cercospora zeina has become a serious disease in maize in China. The isolates of C. zeina from Yunnan, Sichuan, Guizhou, Hubei, Chongqing, Gansu, and Shaanxi were collected. From those, 127 samples were used for genetic diversity analysis based on inter-simple sequence repeat (ISSR) and 108 samples were used for multi-gene sequence analysis based on five gene fragments. The results indicated that populations of C. zeina were differentiated with a relatively high genetic level and were classified into two major groups and seven subgroups. The intra-population genetic differentiation of C. zeina is the leading cause of population variation in China, and inter-population genetic similarity is closely related to the colonization time and spread direction. The multi-gene sequence analysis of C. zeina isolates demonstrated that there were nine haplotypes. Genetic diversity and multi-gene sequence revealed that Yunnan population of C. zeina, the earliest colonizing in China, had the highest genetic and haplotype diversity and had experienced an expansion event. With the influence of the southwest monsoon in the Indian Ocean, C. zeina from Yunnan gradually moved to Sichuan, Guizhou, Shaanxi, Gansu, and Chongqing. Meanwhile, C. zeina was transferred directly from the Yunnan into the Hubei Province via seed and then came into Shaanxi, Henan, and Chongqing along with the wind from Hubei.     

基于线粒体Cytb基因和D-loop区的野生与养殖小黄鱼群体遗传多样性

为研究野生与养殖小黄鱼群体的遗传多样性,基于mtDNA Cytb基因和D-loop控制区对舟山嵊泗海域(SS)和象山三门口海域(SMK)2个小黄鱼野生群体和1个养殖群体(YZ)的遗传结构与遗传分化等进行比较分析。序列分析结果显示,Cytb基因序列为841 bp,其A+T含量(50.2%)与C+G含量(49.8%)相似;D-loop区序列为629～635 bp, A+T含量(58.9%)远高于C+G含量(41.1%)。SS、SMK和YZ群体Cytb基因的单倍型数分别为26、27和12,SS和SMK群体共享2个单倍型(Hap1和Hap13),SMK和YZ群体共享1个单倍型(Hap41);SS、SMK和YZ群体D-loop区的单倍型数分别为27、30和10,SS和SMK群体共享1个单倍型(Hap4)。多样性分析结果显示,3个群体均属于高单倍型多样性(H_d>0.5),其中,SS和SMK群体单倍型多样性和核苷酸多样性高于YZ群体,表明野生群体多样性略高于养殖群体。遗传分化指数显示,2个小黄鱼野生群体间的分化程度极小,而养殖群体与野生群体间存在中度分化。遗传分化指数和A...     

2009年河北省小麦叶锈菌群体EST-SSR遗传多样性分析

通过对小麦叶锈菌群体毒性多态性和EST-SSR多态性分析,为河北省小麦抗病品种的培育和合理利用提供依据。利用34个小麦抗叶锈近等(单)基因系和21对EST-SSR引物对河北省唐山、秦皇岛、沧州、保定、石家庄、邢台和邯郸的30个单孢子分离纯化小麦叶锈菌株进行毒性和DNA多态性分析。结果表明:30株小麦叶锈菌菌株间毒性相似性较高,相似系数为0.70~1.00,分子遗传多态性的相似系数为0.80~1.00。部分地理来源相同的菌株聚在同一亚组,表明小麦叶锈菌株地理来源与毒性多态性和遗传多态性有一定的相关性,但毒性多态性和SSR分子多态性相关性不明显。     

禾谷镰孢复合种毒素化学型及遗传多样性分析

【目的】明确不同省（自治区）引起玉米穗腐病的禾谷镰孢复合种（Fusarium graminearum species complex,FGSC）的毒素化学型和它们之间的遗传差异以及亲缘关系。【方法】选用根据基因Tri13和Tri3序列设计的特异性引物分析来自11个省（自治区）的92株禾谷镰孢复合种菌株的毒素化学型;从100条哥伦比亚大学（UBC）开发的通用引物中筛选出13 条扩增条带丰富、重复性好、信号强、背景清晰的引物,利用筛选出的引物对供试菌株进行ISSR-PCR扩增,使用Popgen32软件计算多态性位点百分率、Shannon’s多样性指数、群体间的遗传距离和遗传相似性;依据Nei’s 遗传距离,利用NTsys2.10e软件进行UPGMA聚类分析,并构建供试菌株的聚类图。【结果】供试的92株禾谷镰孢复合种菌株的产毒素化学型有4种：DON、15-ADON、DON+15-ADON和NIV+15-ADON。其中产生DON和15-ADON的菌株分别为1株和20株;同时产生15-ADON和NIV的有1株;同时产生15-ADON和DON的有55株。筛选出的13条引物对所有供试菌株进行PCR扩增,共获得102条带,其中多态性条带101条,多态性比率为99.02%,平均每条引物产生条带为7.85条。在群体平均水平上,基因多样性指数（H）为0.3129,Shannon’s的信息指数（I）为0.4774,表明禾谷镰孢复合种存在较高的遗传多样性水平;不同地理种群间,各群体的遗传多样性水平具有一定差异,河北、山西、黑龙江和吉林种群遗传多样性最高,安徽和河南种群最低。地理种群间的基因分化系数（Gst）为0.2722,说明不同地理种群间存在一定的遗传变异,但大部分遗传变异（72.78%）发生在种群内。遗传分化系数估算的基因流值Nm=1.3372（＞1）,表明不同地理种群间存在一定的基因流动;遗传关系结果表明河北、山西、黑龙江、吉林、辽宁、内蒙古和甘肃菌株群体间亲缘关系较近,山东、江苏、河南和安徽菌株间亲缘关系较近,安徽和内蒙古菌株间的亲缘关系最远。聚类分析显示所有菌株相似系数为0.43-0.95。在相似系数为0.43时,所有菌株分成2大类群,Group 1包括4株北方春播区菌株（吉林、山西和河北张家口）,不产生NIV和DON;Group 2由余下的88株菌株构成,产生的毒素类型主要为DON和15-ADON,其来源于北方春播区（山西、黑龙江、吉林、辽宁、甘肃和河北张家口、唐山）和黄淮海夏播区（河北石家庄、河南、山东、江苏和安徽）,在相似系数为0.664时,各类群分成不同的亚群,亚群的结果与菌株来源有一定的相关性。聚类分析结果和毒素化学型分析显示,同一地理种群的菌株多数聚在一起,个别菌株分散到不同的分支上。【结论】北方春播区和黄淮海夏播区的禾谷镰孢复合种主要的毒素化学型为DON和15-ADON。引起玉米穗腐病的禾谷镰孢复合种菌株群体内存在丰富的遗传变异,不同地理种群间存在一定的基因交流,遗传多样性与地理来源有关。     

中国西北内陆干旱区大叶白麻野生居群遗传多样性研究(英文)

[Objective] Study on the genetic diversity in wild populations of Poacynum hendersonii.[Method] Random amplified polymorphic DNA(RAPD)technique was employed to analyze the genetic diversity in five wild populations of P.hendersonii sampled from Xinjiang,Gansu and Qinghai provinces.[Result] Totally 165 clear and repeatable bands were generated in RAPD reaction by using 20 primers screened from 80 primers,of which 110 were polymorphic,accounting for 66.67%.At species level,Nei’s gene diversity index(H),Shannon’s information index(I)and genetic differentiation coefficient(Gst)were 0.220 5,0.304 7 and 0.908 2,respectively.P.hendersonii germplasm resources share a high level of genetic diversity,and genetic differentiation mainly exists among the populations.Results from genetic distances and cluster analysis showed that relationships among P.hendersonii populations were to some extent related with their geographical and climatic characters.[Conclusion] This study suggests that the conservation of P.hendersonii should focus on the protection of many populations,particularly the Qinghai population.     

中国西北内陆干旱区大叶白麻野生居群遗传多样性研究(英文)

[Objective] Study on the genetic diversity in wild populations of Poacynum hendersonii.[Method] Random amplified polymorphic DNA(RAPD)technique was employed to analyze the genetic diversity in five wild populations of P.hendersonii sampled from Xinjiang,Gansu and Qinghai provinces.[Result] Totally 165 clear and repeatable bands were generated in RAPD reaction by using 20 primers screened from 80 primers,of which 110 were polymorphic,accounting for 66.67%.At species level,Nei's gene diversity index(H),Shannon's information index(I)and genetic differentiation coefficient(Gst)were 0.220 5,0.304 7 and 0.908 2,respectively.P.hendersonii germplasm resources share a high level of genetic diversity,and genetic differentiation mainly exists among the populations.Results from genetic distances and cluster analysis showed that relationships among P.hendersonii populations were to some extent related with their geographical and climatic characters.[Conclusion] This study suggests that the conservation of P.hendersonii should focus on the protection of many populations,particularly the Qinghai population.     

Genetic Diversity in Wild Populations of Poacynum hendersonii from Inland Arid Regions of Northwest China

[Objective] Study on the genetic diversity in wild populations of Poacynum hendersonii.[Method] Random amplified polymorphic DNA(RAPD)technique was employed to analyze the genetic diversity in five wild populations of P.hendersonii sampled from Xinjiang,Gansu and Qinghai provinces.[Result] Totally 165 clear and repeatable bands were generated in RAPD reaction by using 20 primers screened from 80 primers,of which 110 were polymorphic,accounting for 66.67%.At species level,Nei's gene diversity index(H),Shannon's information index(I)and genetic differentiation coefficient(Gst)were 0.220 5,0.304 7 and 0.908 2,respectively.P.hendersonii germplasm resources share a high level of genetic diversity,and genetic differentiation mainly exists among the populations.Results from genetic distances and cluster analysis showed that relationships among P.hendersonii populations were to some extent related with their geographical and climatic characters.[Conclusion] This study suggests that the conservation of P.hendersonii should focus on the protection of many populations,particularly the Qinghai population.     

Population genetic structure of Chinese Puccinia triticina races based on multi-locus sequences

Puccinia triticina, the causal agent of wheat leaf rust, is one of the most devastating rust fungi attacking wheat worldwide. Seventy-six isolates of the wheat leaf rust pathogen from Yunnan, Sichuan, Gansu and Henan provinces, China, were tested on wheat leaf rust differentials and the population structure was analyzed using four presumably neutral partial sequence markers such as elongation factor-1α(EF-1α), glyceraldehyde-3-phosphate dehydrogenase(GAPDH), β-tubulin(TUB) and the second largest RNA polymerase subunit(RPB2). The phenotypic diversity of Yunnan and Sichuan populations was higher than that of Gansu and Henan populations. The four populations were separated into two clusters based on the pathogenic data. A total of 12 single nucleotide polymorphisms(SNPs) and 32 haplotypes were identified among the four sequences. The 32 haplotypes were divided into two clusters in a neighbor-joining tree. Bayesian analyses also identified two clusters. Pairwise FST between populations in different regions were significantly different(P0.05). Analysis of molecular variance(AMOVA) indicated that 68% of the total genetic variation was within populations.     

中国西北内陆干旱区大叶白麻野生居群遗传多样性研究

[目的]研究大叶白麻野生居群的遗传多样性。[方法]采用RAPD技术对分布于新疆、甘肃和青海的5个大叶白麻野生居群的遗传多样性水平进行检测。[结果]经筛选的20条引物共扩增出165条清晰、重复性好的DNA条带,其中多态性条带为110条,多态位点百分率(PPB)为66.67%。居群间Nei′s多样性指数为0.2205,Shannon’s信息指数为0.3047,遗传分化系数(Gst)为0.9082。大叶白麻具有较高的遗传多样性水平,遗传分化主要发生在居群间。聚类分析显示居群间的相似度与分布区的地理和气候特征相关。[结论]在利用大叶白麻资源的同时,应根据各居群的品质和遗传特征,对这些居群尤其是青海居群加以保护。     

宁夏稻瘟病菌群体遗传结构研究

采用Pot2-rep-PCR指纹识别技术对宁夏稻瘟病菌的群体结构进行分析。根据每个菌株的指纹型将2002至2005年在9个地区采集的406个稻瘟病菌单孢菌株鉴定为65个单元型,其中,单元型NXH7包含176个菌株,占总菌株数的43.3%,在所有年份、地区和大多数水稻品种上出现,是宁夏稻瘟病菌中最广泛适应的单元型。对稻瘟病菌群体的时空变化分析发现,不同年份、不同地区的稻瘟病菌亚群体间遗传分化不明显(地区间Gst=0.0832,年份间Gst=0.0509),遗传结构相似;不同水稻品种上的亚群体遗传分化明显(Gst=0.2823)。提示寄主的选择作用是宁夏稻瘟病菌群体演化的主要力量。宁夏稻瘟病菌菌株间有较高的相似性,总体相似性大于62%,DNA指纹没有任何清晰的系谱结构,没有任何聚类组被大于60%的bootstrap值支持。提示宁夏稻瘟病菌群体可能是单一的无性系谱占绝对优势。总体而言,宁夏稻瘟病菌群体遗传多样性水平较低(H=0.0963,I=0.1806)。     

基于28S rDNA D2区序列的陕南凹缘菱纹叶蝉分子系统学与遗传多样性研究

为探讨陕南桑园凹缘菱纹叶蝉(Hishimonus sellatus Uhler)系统关系与遗传多样性,对陕南7个主要蚕桑产区共132头凹缘菱纹叶蝉的 28S rDNA基因D2区序列进行核苷酸多样性和遗传差异分析,同时研究单倍型之间的分子系统关系和网络进化图。结果表明,总群体共存在多态性位点63个,单倍型8个,优势单倍型H_1占单倍型总数的74.2%,遗传分化程度较低。分子方差分析显示:种群内变异占总组分的98.94%,差异不显著,且其基因流系数Nst和种群地理距离之间不存在相关性(R~2=0.019 7),说明各个地理种群之间存在渐渗杂交。     

Detection and Characterization of ?-Lactam Resistance in Haemophilus parasuis Strains from Pigs in South China

To characterize the ?-lactam resistance in veterinary clinical isolates of Haemophilus parasuis, 115 isolates were examined for the ?-lactam resistance, the possession of ?-lactamase, and the presence of ?-lactamase genes. The genetic relationship among isolates was evaluated by pulsed-field gel electrophoresis (PFGE). Overall, the commonly detected resistance phenotypes were resistant to ampicillin (26.09%), penicillin (22.61%), amoxicillin (21.74%), cefazolin (14.78%), cefaclor (12.17%), and cefotaxime (6.96%). These strains showed high minimal inhibitory concentration (MICs) to oxacillin. 20.87% strains produced ?-lactamase, and 4.35% strains showed extended-spectrum b-lactamase (ESBL) phenotype. Moreover, 19 strains harboured bla genes including TEM-1 (n=5), TEM-116 (n=10), and ROB-1 (n=5). Significantly, one strain possessed both TEM-1 and ROB-1, and displayed resistance to cefotaxime (MIC=8 mg L^-1). The epidemiological analysis of PFGE revealed high genetic diversity among bla-positive isolates. This work shows that TEM- and ROB-type ?-lactamases are prevalent in H. parasuis isolates in China.