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1.
烟蚜茧蜂对蚜虫选择性的数量测定   总被引:1,自引:0,他引:1  
王文夕 《植物保护》1990,16(Z1):18-19
本试验通过对烟蚜茧蜂(Aphidius gifuensis)产卵选择性的研究,认为:(1)对于麦长管蚜(Sitobion.avenae)和麦缢管蚜(Rhopalosiphum padi),烟蚜茧蜂喜欢产卵于麦长管蚜;(2)对于麦长管蚜的不同龄期,烟蚜茧蜂喜欢产卵于麦长管蚜的二—三龄若蚜。  相似文献   

2.
基于生命表技术评价豆柄瘤蚜茧蜂对豆蚜的控害潜能   总被引:1,自引:1,他引:0  
为评价豆柄瘤蚜茧蜂Lysiphlebus fabarum对豆蚜Aphis craccivora的控害潜能,在实验室条件下,通过对豆蚜及其寄生蜂豆柄瘤蚜茧蜂的发育历期、繁殖力、寿命等生物学特性进行观察描述,组建其实验种群生命表,并对2种供试昆虫的生命表参数净生殖力R0、世代平均周期T、内禀增长率rm和周限增长率λ进行了分析。结果表明:豆蚜和豆柄瘤蚜茧蜂的生命表参数R0Trmλ分别为:72.136、23.370 d、0.183、1.201和150.925、10.607 d、0.473、1.605。其中豆柄瘤蚜茧蜂rmR0值均明显大于豆蚜,且豆蚜繁殖1个世代豆柄瘤蚜茧蜂可以繁殖2个世代,表明豆柄瘤蚜茧蜂对豆蚜的寄生能力强,繁殖速率高,对豆蚜种群有较强的控制潜能。  相似文献   

3.
为探讨干旱环境下冬油菜籽粒品质(脂肪酸含量和硫苷)分子遗传机理,以17NTS57(高芥酸)×CY12PXW-6-1(低芥酸)的衍生后代F1、F2、F2∶3等群体为材料,结合天水和定西试点籽粒品质表型,进行干旱环境下籽粒芥酸的遗传定位及选择标记开发。结果表明:利用F2∶3群体在两个试点共检测到油菜芥酸含量QTL位点7个,其中天水试点检测到4个,定西试点检测到3个。天水试点检测到2个主效QTL,即[STBX]qEATC08.2qEATC09[STBZ],分别分布在C08、C09染色体,其表型贡献率在20%以上;[STBX]qEATA10(天水)和qEADA10[STBZ](定西)被定位到A10染色体相同区间,在两个试点的表型贡献分别为10.42%和12.70%;[STBX]qEATC09qEADC09[STBZ]被定位在C09染色体相同区间,两个试点的表型贡献率分别为20.00%和19.34%,为共定位主效QTL。3个QTL([STBX]qEATC08.1(天水)、qEATC08.2(天水)、qEADC07(定西)[STBZ])仅各在一个试点被检测到,其中2个微效修饰位点([STBX]qEATC08.1qEADC07[STBZ])具有正向加性效应。在A10和C09染色体上定位的[STBX]qEA.A10qEA.C09[STBZ]的主效QTL,这些标记可用于干旱条件下油菜籽粒芥酸含量改良的分子标记辅助选择。  相似文献   

4.
为评价转Cry2Aa基因水稻T2A-1对二化螟盘绒茧蜂Cotesia chilonis的安全性,采用饲喂法和微注射法综合评价转Cry2Aa基因水稻T2A-1对二化螟盘绒茧蜂的影响。结果表明,寄生饲喂转Cry2Aa基因水稻T2A-1的二化螟Chilo suppressalis后,二化螟盘绒茧蜂体内未检出Cry2Aa蛋白,其每茧块茧数、茧长、雄成虫寿命和雌雄比分别为20.00个、2.58 mm、2.34 d和3.10,均显著小于对照,而卵及幼虫的总历期、蛹期、雌成虫寿命、茧质量和成虫质量均与对照差异不显著;寄生微注射Cry2Aa蛋白的二化螟后,除卵及幼虫的总历期和蛹期外,二化螟盘绒茧蜂其他生命表参数和体内过氧化物酶(peroxidase,POD)、超氧化物歧化酶(superoxide dismutase,SOD)和谷胱甘肽还原酶(glutathione reductase,GR)活力均与阳性对照之间差异显著;寄生微注射Cry2Aa蛋白的二化螟后,二化螟盘绒茧蜂所有生命表参数及体内POD、SOD和GR活力均与阴性对照之间无显著差异。表明饲喂法中转Cry2Aa基因水稻T2A-1对二化螟盘绒茧蜂产生的影响是由寄主介导效应引起的,而非Cry2Aa蛋白本身,因此转Cry2Aa基因水稻T2A-1对二化螟盘绒茧蜂安全。  相似文献   

5.
群体遗传学研究对于了解病原菌的流行、变异及进化规律具有重要意义。但是到目前为止,对小麦纹枯病菌禾谷丝核菌群体遗传结构的了解并不深入,缺乏有效的SSR标记是主要原因。本研究根据禾谷丝核菌全基因组序列进行了微卫星位点搜索并设计SSR引物,通过电泳筛选和测序验证,最终筛选出12个多态性较好且稳定可靠的SSR标记。利用这些标记对收集自我国安徽、江苏、河南三省的23个禾谷丝核菌菌株进行了多态性分析,结果发现禾谷丝核菌基因组中长片段微卫星位点较少。12对引物扩增出的等位基因数平均为6.1个,期望杂合度平均为0.651,观测杂合度平均为0.508,表明这些标记具有较高的多态性,能够满足禾谷丝核菌群体遗传学研究需要。本研究为进一步进行禾谷丝核菌的多样性、群体遗传结构分析及进化学研究提供了有效工具。  相似文献   

6.
为了探究生长年限对衰败期苜蓿和中老龄柠条的叶片光合生理特征及土壤水分的影响,在2014年于地处黄土高原水蚀风蚀交错带强烈侵蚀中心的神木六道沟小流域,测定了不同生长年限苜蓿(ALF10、ALF13、ALF33和ALF49)和柠条(KOP10、KOP25、KOP43和KOP73)的叶片光合参数、叶结构性状参数以及0~400 cm土层土壤体积含水量(SWC0-400)。结果表明:对于衰败期苜蓿,ALF10和ALF13叶片净光合速率(Pn)差异不显著(P>0.05),而后随生长年限的延长逐渐降低,ALF33和ALF49比ALF13叶片的Pn(24.01 μmol·m-2·s-1)分别降低了2.32 μmol·m-2·s-1和7.76 μmol·m-2·s-1。相比ALF10,随生长年限延长SWC0-400恢复至10.88%(ALF13),而后随着生长年限延长降低至8.81%(ALF33)和6.12%(ALF49)。土壤水分对ALF33的限制作用不明显,水分胁迫使ALF49非气孔限制值比ALF33增大了0.340。对于中老龄期柠条,叶片Pn随生长年限的延长先升高后降低,KOP25和KOP43叶片Pn最大且两者差异不显著(P>0.05),比KOP10(6.62 μmol·m-2·s-1)分别增大了6.57 μmol·m-2·s-1和7.66 μmol·m-2·s-1,KOP73比KOP43叶片Pn降低了4.95 μmol·m-2·s-1。对于同为黄绵土生长的KOP10、KOP43和KOP73,SWC0-400随生长年限延长逐渐上升,分别为8.50%、9.06%和10.71%。土壤水分恢复使KOP43叶片气孔及非气孔限制值比KOP10柠条降低了0.185和2.180。此外,柠条叶片相对叶绿素含量(SPAD)与Pn呈极显著正相关(P<0.001),相关系数为0.514。研究结果表明衰败期苜蓿和中老龄期柠条叶片光合性能呈波动式变化,这与土壤水分的相互作用有关。  相似文献   

7.
一品红花卉上烟粉虱的序贯抽样技术研究   总被引:1,自引:0,他引:1       下载免费PDF全文
王立红 《植物保护》2007,33(4):74-76
烟粉虱[Bemisiatabaci(Gennadius)]在花卉一品红上的为害十分猖獗,在调查分析的基础上,研究了烟粉虱在一品红上的序贯抽样技术。结果表明:烟粉虱成虫的平均拥挤度*m与平均密度x-回归方程为*m=-9.05+2.26x-,相关性极显著(0.799 1);以Iwao的序贯抽样为基础,结合Kuno的序贯抽样,提出复序贯抽样技术,防治指标上下限为T0(n)=7n+2 5.39n,T0(n)=7n-2 5.39n,截止线为T(n)=α+1/(D02-β-1/n),D0=0.15。  相似文献   

8.
方睿  ;钟俊鸿 《植物保护》2007,33(3):58-61
采用线粒体COⅡ基因为分子标记对中国南部4个台湾乳白蚁地理种群的遗传分化进行了初步研究。结果显示,4个地理种群共有9个多态位点和8种单倍型;种群间遗传分化统计量Fst与地理距离无显著相关。探讨了台湾乳白蚁种群分化的影响因素和相应的防治对策。  相似文献   

9.
为查明西藏小麦条锈菌Puccinia striiformis f. sp. tritici群体结构和遗传多样性,采用中国鉴别寄主和近等基因系鉴别寄主,以及竞争性等位基因特异性PCR-单核苷酸多态性(kompetitive al-lele specific PCR-single nucleotide polymorphism,KASP-SNP)分子标记对2017年采自西藏的150个小麦条锈菌菌系分别进行表型分析和基因型分析。表型分析结果显示,中国鉴别寄主将150个菌系区分为 12 个已知小种、6 个已知致病类型和 13 个未知致病类型,所有菌系均不能侵染中四和Triticum spelta album鉴别寄主。近等基因系鉴别寄主将150个菌系区分为88个毒性类型,这些毒性类型均不侵染携带抗性基因Yr5Yr10Yr15的品种。基因型分析结果显示,26对引物将150个菌系划分为73个基因型,表明西藏小麦条锈菌群体基因型丰富。基因流分析结果表明,波密县与洛扎县小麦条锈菌亚群体之间的基因流Nm最高,达5.86,米林县西部与波密县、洛扎县、巴宜县、米林县东部条锈菌亚群体之间的Nm较低,分别为0.25、0.34、0.42和0.67,表明西藏不同地区条锈菌群体之间基因交流强度差异较大。说明西藏作为我国小麦条锈病的独立流行区,条锈菌群体毒性结构复杂,遗传多样性高。  相似文献   

10.
基于转录组数据的印度谷螟微卫星位点分析   总被引:1,自引:0,他引:1  
基于印度谷螟转录组测序数据筛选其功能微卫星(EST-SSR)分子标记,设计该虫的微卫星(SSR)引物并验证其适用性。用MicroSAtellite微卫星搜索软件查找印度谷螟转录组中微卫星的数量、重复次数以及所有微卫星的位置信息,采用Primer Premier 5软件设计SSR引物,并进行PCR验证。结果表明含EST-SSR的序列3 173个,占总搜索序列的8.52%,平均每13kb中就出现1个EST-SSR。共发现192种微卫星类型,其中重复单元为单碱基、二碱基和三碱基的比例较高,依次是28.21%、39.84%、25.43%。除单碱基重复单元外,出现频率最高的是AT/AT,有593次。在66对印度谷螟EST-SSR引物中,有28对PCR扩增成功。这说明基于印度谷螟转录组数据开发微卫星标记是可行的,本研究获得的印度谷螟EST-SSR位点为今后开展该虫的种群遗传学研究提供了基础数据。  相似文献   

11.
为研究苹果小吉丁虫Agrilus mali Matsumura的种群遗传结构,采用磁珠富集法以生物素标记探针(AC)_(12)和(AG)_(12)构建苹果小吉丁虫微卫星文库,根据阳性克隆测序获得的微卫星侧翼序列设计引物,筛选和开发苹果小吉丁虫多态性微卫星标记,并利用开发的微卫星标记对其不同地理种群的遗传结构进行分析。结果显示,从微卫星文库中的300个阳性克隆中筛选得到248个含有微卫星片段的克隆子,阳性克隆率为82.7%,其中完美型微卫星131个,占52.8%;不完美型90个,占36.3%;混合型27个,占10.9%,表明磁珠富集法开发新微卫星标记的效率较高。从获得的248个苹果小吉丁虫微卫星中筛选获得7个多态性微卫星位点,这7个位点在苹果小吉丁虫8个地理种群样本中的等位基因数为10~23个,有效等位基因数为1.674~12.218个,多态信息含量为0.304~0.796。8个苹果小吉丁虫种群的观测杂合度为0.095~0.676,期望杂合度为0.469~0.755,Shannon指数为0.791~1.621,遗传距离为0.071~0.788。采自新疆维吾尔自治区的7个苹果小吉丁虫种群之间遗传相似度较高,但其与辽宁省种群的遗传相似度较低。  相似文献   

12.
为筛选用于我国禾谷缢管蚜种群遗传学研究的微卫星位点,从8个省(市)共9个地区采集282头试虫,采用微卫星PCR产物荧光标记与自动扫描分型方法,研究了8个欧洲禾谷缢管蚜微卫星位点在试虫个体中的扩增稳定性和遗传多样性。结果显示:位点R1.35在9个种群中均不能扩增;位点R5.29b只在7个种群的少数样本中能扩增;位点R2.73、R3.171、R5.10、R5.138、R5.50和R6.3在各种群中均能稳定扩增,这6个位点的无效等位基因频率为0.0044~0.2663,平均等位基因数为2.9~9.3个,观测杂合度为0.047~0.912,其中位点R6.3具有较低的观测杂合度(0.047)和等位基因数(2.9),不适合用于种群遗传多样性研究,而位点R2.73、R3.171、R5.10、R5.138和R5.50均具有较高的杂合度和等位基因数,可用于我国禾谷缢管蚜的种群遗传学研究。  相似文献   

13.
The Oomycete Plasmopara viticola is the causal organism of downy mildew on grapevine (Vitis spp.). In order to set up the techniques for investigating downy mildew disease dynamics and genetic structure, co-dominant, neutral, highly reproducible and polymorphic microsatellite markers for P. viticola were developed. Five markers, two with a (TC)n repeat (loci BER and ISA), two with a (TC)n(AC)n repeat (loci CES and REX) and one with a (CT)n(CTAT)n repeat (locus GOB), were selected. Simple sequence repeat (SSR) markers revealed different degrees of polymorphism within 190 oil spots (disease symptoms) collected from an infected Italian vineyard. The most polymorphic SSR marker GOB showed 43 alleles (Nei's expected gene diversity He = 0.89) while CES, ISA, BER and REX showed 14 (He = 0.71), 4 (He = 0.57), 3 (He = 0.24) and 1 allele (He = 0), respectively. A high throughput DNA extraction method, that allowed molecular analysis of this obligate pathogen directly in the host without any isolation procedure, was developed. The quality and quantity of oil spots did not influence the SSR analysis. Amplified SSR loci were separated by electrophoresis on a Beckman–Coulter 2000XL sequencer and automatically analysed. The objective of this study was to develop molecular biological tools and methods that allow high throughput analysis of the downy mildew populations.  相似文献   

14.
Sclerotinia trifoliorum, an important pathogen of cool season legumes, displays both homothallism and heterothallism in its life cycle, unique among members of the genus Sclerotinia. Very little is known about its genetic diversity and population structure. A sample of 129 isolates of S. trifoliorum from diseased chickpea in California was investigated for genetic diversity, population differentiation and reproductive mode. Genetic diversity was estimated using mycelial compatibility (MCG) phenotypes, rDNA intron variation, and allelic diversity at seven microsatellite loci. Genetic analysis revealed high levels of genotypic diversity demonstrated by high genotypic richness (0·88). Similarly, high levels of gene diversity (mean expected heterozygosity HE = 0·68) were observed at the microsatellite loci. Geographic populations of S. trifoliorum were highly admixed as evident from low FST values (0–0·11), suggesting high contemporary or historical gene flow. Hierarchical analysis of molecular variance showed that more than 92% of the genetic variation occurred among isolates within populations. Bayesian clustering analysis identified four cryptic genetic populations that were not correlated to geographic location, and index of multilocus association was non‐significant in each of the four genetic populations. However, the presence of identical haplotypes within and among populations indicates clonal reproduction. The high levels of haplotype diversity and population heterogeneity, a lack of correspondence between MCG and microsatellite haplotype, and low levels of population differentiation suggest that populations of S. trifoliorum in chickpea have been undergoing extensive outcrossing and migration events probably shaped by human‐mediated dissemination, the underlying diverse cropping systems, and chickpea disease management practices.  相似文献   

15.
为探明烟蚜茧蜂Aphidius gifuensis Ashmead对烟蚜Myzus persicae(Sulzer)取食感染马铃薯Y病毒(Potato virus Y,PVY)烟株的适应性,利用刺探电位图谱(EPG)技术记录了烟蚜在感病烟株与健康烟株上的取食行为,并测定了烟蚜茧蜂对取食2种烟株烟蚜的寄生率以及烟蚜茧蜂的羽化率、发育时间及性比等指标。结果表明,与健康烟株相比,烟蚜在感染PVY烟株上的第1次刺探取食持续时间显著延长,且口针遇到阻力的次数(F波)和总持续时间均显著减少。烟蚜在感病烟株木质部的吸食时间(G波)显著长于健康烟株。感病烟株上烟蚜在韧皮部阶段的分泌唾液时间(E1波)较在健康烟株上显著缩短,而被动吸食汁液时间(E2波)显著延长。烟蚜茧蜂寄生取食感染PVY烟株的烟蚜,虽然能成功完成其生活史,但适应性与寄生取食健康烟株烟蚜的蚜茧蜂存在差异。在感染PVY烟株上,烟蚜茧蜂对烟蚜的寄生率为33.67%,显著低于对照的64.67%;且僵蚜体重明显下降,羽化的成蜂个体较小;成蜂存活时间1.48 d也极显著短于对照组的2.25 d。表明烟蚜茧蜂对取食感染PVY烟株烟蚜的适应性较低,PVY可通过烟蚜为介体间接降低烟蚜茧蜂的适应力。  相似文献   

16.
In the current agronomical context of pesticide use reduction, deciphering the genetic bases of pathogen adaptation to plant defences is of major importance to improve durability of resistance. Indeed, knowledge of virulence gene frequencies in pathogen populations could allow the prediction of resistance durability before deployment. Globodera pallida is a major pest of potato crops for which a promising resistance QTL, GpaVvrn, has been identified in Solanum vernei. An experimental evolution study, in which G. pallida lineages evolved on resistant or susceptible potato genotypes for up to eight generations, previously showed that G. pallida was able to rapidly overcome GpaVvrn resistance. However, it was not known if enough genetic mixing occurred in these lineages to be able to detect islands of differentiation in a genome scan approach. Here, this question was investigated using 53 polymorphic microsatellite markers distributed along the genome and three different tests based on genetic differentiation and heterozygosity. Eight outlier loci were identified, indicative of genomic regions putatively involved in host adaptation. Several loci were identified by multiple detection methods and/or in two independent adapted lineages. Some candidate genomic regions identified also seemed to be involved in overcoming resistance to nematodes in a plant genotype harbouring the same resistance QTL in a different genetic background. These results validate the feasibility of a genome scan approach on biological material coming from short experimental evolution, and encourage the use of a high coverage genome scan by whole genome resequencing.  相似文献   

17.
The aim of this study was to develop new polymorphic markers for analysis of genetic diversity in the fungal soilborne plant pathogen Verticillium dahliae. Twelve polymorphic markers (five microsatellites and seven polymorphic sequences) were developed from a genomic library enriched for microsatellites. Screening of polymorphic loci was done using a collection of 25 V. dahliae isolates of diverse geographic origins, host sources and vegetative compatibility groups (VCGs). Three methods were used to score alleles: polyacrylamide gel electrophoresis (PAGE), sequencing of PCR‐amplified loci, and capillary electrophoresis. The new markers were used to assess genetic differentiation between isolates associated with different host plants. Two collections of isolates were analysed, obtained from artichoke (30 isolates) and potato (20 isolates) from crops grown in rotation located in the same area in eastern‐central Spain. The resolution of genetic differentiation between these two collections using the new markers was compared to that provided by other often‐used markers (SCARs and VCGs). Sequence analysis of the alleles proved to be the most unambiguous technique for scoring microsatellite data. The relatively high genetic differentiation observed between isolates from different crops (genetic differentiation coefficient, GST = 0·24) and their high genotypic diversity suggest a divergence between V. dahliae from artichoke and potato. It is hypothesized that evolution of V. dahliae from the local resident population in association with the two host crops has occurred. The new markers are useful for resolving population structure within V. dahliae and may contribute to a better understanding of the population biology of this fungus.  相似文献   

18.
The genetic diversity and relationships of 48 Lolium temulentum accessions derived from eight countries (Morocco, Egypt, Tunisia, Italy, Ethiopia, Pakistan, Nepal and Japan) were analysed using seven microsatellite and 44 AFLP polymorphic loci to investigate the origin and distribution of genetic variation. Cluster analysis was performed using the unweighted pair-group method with arithmetic averages (UPGMA) based on the simple matching coefficient of similarity. Nei's gene diversity (h) and the coefficient of gene differentiation (Gst) were calculated. The results from microsatellite analysis indicated that accessions from the same country did not always cluster together, probably because of the limited number of loci used. In contrast, AFLP clearly separated clusters between countries and/or regions; Pakistan–Nepal complex, the Mediterranean region, Ethiopia and Japan. The h value was much higher for microsatellite than for AFLP analysis, indicating that microsatellites are the more variable markers. For AFLP analyses, h values were highest in accessions from Pakistan–Nepal complex, and from the Mediterranean region. These are in agreement with proposals that the origin of L. temulentum lies between the South-western Asia and the Mediterranean basin. The clear groupings of accessions from each country and/or region with high Gst (0.688) indicate that exchange of seeds between them is limited.  相似文献   

19.
Schoenoplectus juncoides is one of the most harmful weeds found in East Asian paddy fields. Recent emergence of biotypes that are resistant to the herbicide sulfonylurea (SU) has made weed control difficult. To examine the effect of the evolution of this herbicide resistance on genetic diversity within local populations, we investigated microsatellite variability within and among paddy field populations of S. juncoides in Kinki, Japan. In vivo assay of acetolactate synthase activity and root elongation assay in the presence of SU revealed that of 21 populations, five were sulfonylurea‐susceptible (SU‐S) and eight were completely sulfonylurea‐resistant (SU‐R). The remaining eight populations were a mixture of SU‐S and SU‐R individuals. The average gene diversity for SU‐R populations (HS = 0.168) was lower than those for SU‐S (HS = 0.256) and mixed (HS = 0.209) populations, but the difference was not significant. This indicates that positive selection for SU‐R phenotype did not cause a genome‐wide reduction in genetic diversity. Genetic differentiation among S. juncoides populations was higher than that observed for most weed species studied previously. Although populations in neighbouring paddy fields showed a high level of differentiation, Bayesian clustering analyses suggested that some level of gene flow occurs among them and that the genetic exchange or colonisation between neighbouring populations could contribute to the geographical expansion of the resistant allele.  相似文献   

20.
为揭示欧洲苹果蠹蛾微卫星位点在中国苹果蠹蛾群体遗传学研究中的有效性,以12对微卫星引物对采自中国主要疫区新疆、甘肃、黑龙江的8个苹果蠹蛾地理种群的120头个体在各位点的遗传多样性及扩增稳定性进行研究。所选取的12个微卫星位点中,有8个能够稳定扩增,各位点在大多数种群中均显示偏离哈迪-温伯格平衡,各位点上的平均等位基因数量为3.750~12.500,平均观察杂合度Ho为0.025~0.783,平均期望杂合度He为0.284~0.892。位点Cp2.P和Cp4.56分别具有较低的观察杂合度(0.109、0.025)和较高的近交系数Fis(0.806、0.954),说明这2个位点上的杂合子非常缺乏,其余6个位点均具有较高的杂合度水平和等位基因数量,适用于中国疫区内苹果蠹蛾微卫星分子标记研究。  相似文献   

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