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Summary During the period 1995–1999 one hundred and sixty three isolates of P. infestans were collected in Ireland. The majority (150)
were from the 1996 population. Isolates were analysed for mating type and sensitivity to metalaxyl, and subsets were also
genotyped for mitochondrial haplotype (124) and RG-57 fingerprint (114). Four of the isolates tested were of the A2 mating-type. Of four haplotypes known, only two were detected in the Irish population. RG-57 probe analysis determined that
there were 12 genotypes present. However, clustering analysis demonstrated close relationships between many of the strains
found. Metalaxyl resistance was predominantly associated with two closely-related genotypes. All A2 isolates shared the same genotype. Due to the low population diversity, especially of A2, sexual reproduction does not appear to be a factor in disease epidemiology. 相似文献
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ZHOU Zhen-ling WEI Xiang-jin JIANG Ling LIU Kai XU Da-yong ZHAI Hu-qu WAN Jian-min 《水稻科学》2011,18(4):287-296
Heading date of 26 native japonica rice cultivars in southwest China was investigated,and their basic vegetative growth(BVG),photoperiod-sensitivity(PS) and temperature-sensitivity(TS) were analyzed under artificial short-day and natural long-day conditions in Nanjing,as well as artificial high-temperature and natural low-temperature conditions in winter in Hainan.The results showed that the PS and TS varied among different cultivars.The BVG of all the japonica cultivars was well situated,but differed withi... 相似文献
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利用重测序的水稻染色体片段代换系群体定位剑叶形态QTL 总被引：1，自引：1，他引：1
剑叶形态性状（剑叶长、剑叶宽和剑叶面积）是水稻理想株型育种的重要目标性状之一。发掘新的控制水稻剑叶形态性状的基因资源,准确鉴定和定位水稻剑叶形态性状QTL,对开展水稻剑叶形态性状分子生物学研究和理想株型分子育种都具有重要意义。 以通过高通量测序而准确获知代换片段位置及长度的一套用籼稻品种9311为受体、粳稻品种日本晴为供体构建的,包括128个染色体片段代换系群体为材料,对剑叶形态性状及其与主穗颖花之间的相关性进行分析,结果表明剑叶面积与剑叶长、宽呈极显著正相关,主穗颖花数与剑叶长、剑叶面积呈极显著正相关。利用多元回归分析方法,结合Bin map,共鉴定出与水稻剑叶长、宽和面积相关的QTL分别为4、4和6个,贡献率介于4.08%~60.40%。上述QTL的准确定位,为进一步精细定位及克隆相应QTL以及开展水稻剑叶形态性状分子育种奠定了基础。 相似文献
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2006～2008年在黑龙江省和吉林省共分离获得99株马铃薯晚疫病菌,并测定了这些菌株的交配型、瑞毒霉敏感性、同工酶基因型和mtDNA单倍型。交配型测定结果显示在吉林省和黑龙江省分离的所有菌株均为A1交配型。瑞毒霉敏感性测定结果显示敏感性菌株占14.1%,中抗菌株占7.1%,抗性菌株占78.8%,表明吉林省和黑龙江省发生的晚疫病菌已对瑞毒霉产生抗药性。黑龙江省和吉林省分离的所有菌株中发现了两种mt DNA单倍型(Ⅰa和Ⅱa)。其中,Ⅰa单倍型占11.1%,Ⅱa单倍型占88.9%。根据Gpi和Pep图谱,本试验发现了3种同工酶基因型,其中优势同工酶基因型是Gpi:100/100,Pep:100/100。根据菌株的交配型、同工酶基因型和mtDNA单倍型,共发现4种基因型,其中,multi-locus基因型A(84.9%)是黑龙江省和吉林省发现的优势基因型,但也出现了新的基因型分化。 相似文献
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Khalid P. Akhtar Ghulam SarwarGhulam Abbas Muhammad J. AsgharNighat Sarwar Tariq M. Shah 《Crop Protection》2011,30(9):1202-1209
Yellow mosaic disease (YMD) caused by whitefly (Bemisia tabaci) transmitted mungbean yellow mosaic India virus (MYMIV) is an important constraint of mungbean in Pakistan. One hundred sixty-two mungbean genotypes from eight different geographic regions were evaluated for resistance to MYMIV and its whitefly vector B. tabaci. Resistance levels were assessed by visual scoring of symptoms in the field under natural conditions, in net-house by artificial transmission through whitefly and in greenhouse using graft inoculation for two consecutive years in 2008 and 2009. None of the tested genotypes was found to be disease free, while considerable variation in responses was observed among the genotypes and testing methods. All genotypes were found to be systemically infected in the field. In 2008, 32 genotypes were found to be resistant and 67 were moderately resistant with severity index (SI) values ranging from 1.0 to 1.4 and from 1.5 to 2.4, respectively. In 2009 34 genotypes were found to be resistant and 38 were moderately resistant with the same SI value ranges as in 2008, and the remaining genotypes were moderately susceptible to highly susceptible. However, only 35 genotypes were found to be moderately resistant with SI values of 1.5-2.4 and latent periods (LP) of 17-21 days when evaluated using artificial transmission through whiteflies. Similar results were obtained when these genotypes were evaluated using graft inoculation. Significant differences in adult whitefly densities among tested genotypes were also observed during both years but no correlation between the number of whiteflies and disease severity was observed. The results indicated that these genotypes did not have a high level of resistance against MYMIV, however, they may provide sources of partial resistance which can be exploited in the breeding programmes to develop mungbean genotypes resistant to MYMD or they can be used directly as varieties to manage MYMD after evaluation for acceptable agronomic characteristics, adaptation and stability in various regions. 相似文献
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Ercisli S Tosun M Karlidag H Dzubur A Hadziabulic S Aliman Y 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(3):271-276
Fruit skin color, total phenolics, total anthocyanins, soluble solids content, titratable acidity and total antioxidant capacity in fresh fruits of a number of local and well-known fig (Ficus carica L.) genotypes and cultivars grown in northeastern Turkey were determined. TEAC (Trolox equivalent antioxidant capacity) and FRAP (ferric reducing antioxidant power) assays were used to determine total antioxidant capacity. Fruit skin color of genotypes were found to be very diverse, i.e., light green, light purple, purple, dark purple and black. The content of total phenolics, soluble solids content (SSC) and titratable acidity greatly varied in the range from 24 to 237?mg of gallic acid equivalent per 100?g fresh weight, 18.60 to 26.30?% and 0.16 to 0.47?% in local genotypes and studied cultivars. In general, total antioxidant capacities determined by two methods expressed higher values in the local fig genotypes compared with the cultivars. The results suggested that genotype is the main factor that determines difference in the composition of bioactive compounds in figs and provide information on putative health benefits locally grown genotypes. 相似文献
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Botrytis grey mould (BGM), caused by Botrytis cinerea Pers. Ex. Fr., is a destructive foliar disease of chickpea (Cicer arietinum L.) worldwide. Disease management through host-plant resistance is the most effective and economic option to manage this disease. The objective of this study was to identify new sources of resistance to BGM, validate their stability across environments and determine the magnitude of G × E interaction. One hundred and nine chickpea genotypes with moderate levels of resistance (BGM severity ≤5.0 on a 1–9 scale) were selected from the preliminary evaluation of 412 genotypes including germplasm and breeding lines under controlled environmental conditions in 2004–2005 at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, India. In order to validate resistance stability, an ‘International Botrytis Grey Mould Nursery’ (IBGMN) was constituted with 25 genotypes and tested in multi-environments for BGM resistance at two locations (Gurdaspur and Pantnagar) in India for 4 years and two locations (Tarahara and Rampur) in Nepal for 3 years. Additive main effects and multiplicative interaction (AMMI) analysis showed significant genotype (G), environment (E) and G × E interaction (p < 0.0001) with largest contribution by environment (47.36%). The first two principal component axes were significant, and contributed 48.21% to the total G × E interaction. The AMMI biplot analysis allowed the selection of five genotypes ICCV 96859, ICCV 96853, ICCV 05604, ICCV 96852 and ICCV 05605 with low BGM severity (between 3.7 and 4.7 on 1–9 scale) and moderate stability. Genotype ICCV 96859 having least disease severity and moderate stability could be highlighted and exploited in chickpea resistance breeding programmes. 相似文献
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Field studies were organized for exploring the moss flora of Hatila Valley National Park of Artvin (Turkey) during spring-summer period in 2005-2006. The taxonomic survey yielded eighty-five moss taxa o(comprises of seventy-nine species, six varieties) belonging to 44 genera of 16 families in Hatila Valley National Park of Artvin, Turkey. Bryum rubens Milt., Dicranodontium uncinatufm (Harv.) A. Jaeger., Eurhynchium hians var. rigidum (Boul.) Düll., Hypnum jutlandicum Holmen and Warncke, Rhynchostegiella jacquinii (Garov.) Limpr. and Pseudocrossidium hornschuchianum (Schultz) R. H. Z ander are new records for A4 grid square (40 degrees-42' N, 38 degrees-42' E) determined. All taxa were found for the first time in Artvin. For every each taxon, the habitat pattern and distribution data are presented. 相似文献
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BACKGROUND: Enterococci are important because of their role as the leading cause of nosocomial infections which have a significant role in the dissemination and persistence of antimicrobial resistance genes. METHODS: In this study, we determined the distribution of enterococcal species in the sewage treatment plants in Iran. Furthermore, we improved a rapid and specific PCR method using primers (sodA and ddl genes) for identification of enterococci spp. RESULTS AND CONCLUSION: A total number of 712 enterococci spp. were isolated and the results showed that 56%, 24%, 12%, 4%, 2%, 1% and 1% isolates were E. faecium, E. hirae, E. faecalis, E. gallinarum, E. casseliflavus, E. mundtii and other enterococcal spp., respectively. The use of species-specific PCR was in agreement with the biochemical tests. Furthermore, multiplex PCR was developed to study the presence of vancomycin resistant genes in E. faecium or E. faecalis. The multiplex PCR appeared to be a useful, rapid and specific method for detecting and discriminating genotypes for vancomycin-resistant Enterococcus. 相似文献
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花生种质资源对黄曲霉菌侵染的反应 总被引：8，自引：3，他引：8
对来自我国不同生态区的700份花生种质进行抗黄曲霉菌侵染的评价。鉴定结果表明,700份花生种质中,大部分对黄曲霉菌侵染表现高感,低侵染率（50％以下）种质仅12份,其中EF7284的侵染率最低,为28．57％。低侵染率花生种质均来自南方生态区的珍珠豆型材料,本文对低侵染率花生种质的主要植物学,农艺性状及品质性状作了分析评价。 相似文献
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《Field Crops Research》2002,73(2-3):181-200
A series of experiments were conducted in drought-prone northeast Thailand to examine the magnitude of yield responses of diverse genotypes to drought stress environments and to identify traits that may confer drought resistance to rainfed lowland rice. One hundred and twenty eight genotypes were grown under non-stress and four different types of drought stress conditions.Under severe drought conditions, the maintenance of PWP of genotypes played a significant role in determining final grain yield. Because of their smaller plant size (lower total dry matter at anthesis) genotypes that extracted less soil water during the early stages of the drought period, tended to maintain higher PWP and had a higher fertile panicle percentage, filled grain percentage and final grain yield than other genotypes. PWP was correlated with delay in flowering (r=−0.387) indicating that the latter could be used as a measure of water potential under stress. Genotypes with well-developed root systems extracted water too rapidly and experienced severe water stress at flowering. RPR which showed smaller coefficient of variation was more useful than root mass density in identifying genotypes with large root system.Under less severe and prolonged drought conditions, genotypes that could achieve higher plant dry matter at anthesis were desirable. They had less delay in flowering, higher grain yield and higher drought response index, indicating the importance of ability to grow during the prolonged stress period.Other shoot characters (osmotic potential, leaf temperature, leaf rolling, leaf death) had little effect on grain yield under different drought conditions. This was associated with a lack of genetic variation and difficulty in estimating trait values precisely.Under mild stress conditions (yield loss less than 50%), there was no significant relationship between the measured drought characters and grain yield. Under these mild drought conditions, yield is determined more by yield potential and phenotype than by drought resistant mechanisms per se. 相似文献
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The basic aim of the sprinkler irrigation method, as in other irrigation methods, is to apply irrigation water as uniformly as possible to the root zone. The uniform distribution of the applied water in sprinkler irrigation depends on factors such as sprinkler type, number and size of nozzles, arrangement of sprinklers, working pressure and the speed and direction of the wind. Sprinkler and lateral spacing should be determined by also taking the speed and direction of the wind into consideration. The aim of this study was to determine the application limits and the curves of water distribution under different working pressures, spatial arrangement and nozzle diameters under field conditions of some irrigation sprinklers which are widely used in Turkey. The objective was to determine the most appropriate system arrangement by using a computer program called CATCH3D. Five sprinklers were tested in the experimental area of Ondokuz Mayis University Campus and their water distribution characteristics identified. The most suitable operating parameters for Bereket 3: 12 x 18 m, Bereket 2: 12 x 18 m, Egeyildiz 6 x 18m, Goktepe 6 x 12 m and for Atesler sprinkler 12 x 18 m arrangement type were determined. 相似文献
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为了发掘更多的小麦白粉病抗性种质资源,对收集到的168份小麦不同病害抗性材料进行了白粉病苗期和成株期抗性鉴定,并利用STS标记csLV34以及功能标记cssfr3、cssfr4、cssfr5和Yr18E11a对其Lr34/Yr18/Pm38位点的等位变异类型进行检测。结果表明,在168份小麦种质中,共鉴定出41份白粉病苗期抗性品种(系)以及96份慢白粉病品种(系)。功能标记cssfr3和cssfr4可准确鉴定Lr34/Yr18/Pm38位点第11外显子中的等位变异,而功能标记cssfr5和Yr18E11a在检测时存在小频率的错判。在96份慢白粉病材料中,有24份材料携带Lr34/Yr18/Pm38的等位变异类型,这些材料在2个年份下的白粉病田间MDS均低于不携带Lr34/Yr18/Pm38的等位变异类型的材料。 相似文献
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This study aimed to determine the resistance/susceptibility to fire blight of apple germplasm resources from the province of Erzincan in eastern Turkey. In total, 32 native apple accessions from four regions within the province were tested under greenhouse conditions by inoculating the shoot tips with pathogenic bacterium. Shoot tips were wounded for inoculation. Genotypical susceptibility index (GSI%) values were computed for each genotype based on the length of the lesion that developed on each shoot. Accessions were grouped into five classes of resistance/susceptibility, as follows: Class A (resistant); Class B (moderately resistant); Class C (moderately susceptible); Class D (susceptible); and Class E (highly susceptible). GSI% values differed significantly among accessions (p < 0.01). Five accessions received a rating of Class A, and 7 accessions received a rating of Class B. This was followed by 9 accessions with a rating of Class C, 5 accessions with a rating of Class D and 6 accessions with a rating of Class E. The findings of this study are expected to contribute to breeding efforts with respect to apple resistance to fire blight. 相似文献
16.
启动氮加追肥对氮在大豆体内积累分配规律及产量的影响 总被引：2，自引：0，他引：2
采用框栽试验方法,在施用等量氮(纯N 50 kg.hm-2)条件下设置基肥一次性施用(对照);R3或R4期一次性追肥;启动氮15 kg加R3或R4期追氮35 kg共5个处理,研究启动氮加追肥对氮在大豆体内积累分配规律及产量的影响。结果表明,在R5期,与对照相比,启动氮15 kg加R4期追氮35 kg处理叶片N积累量减少11.5%,荚果N积累量增加36.6%(P<0.05);而根系N积累量增加21.7%(P<0.05),根瘤N积累量增加64.2%(P<0.05),表明启动氮加追肥处理N运转通畅,可以满足籽粒充实期大豆对氮素的需求。在R4～R8期,启动氮加R3或R4期追氮处理的氮积累量分别比基肥一次性施用处理增加82.6%和105%(P<0.01)。启动氮加R3或R4期追氮35 kg处理单株粒数分别较对照增加14.8%和15.8%(P<0.01),产量分别增加17.6%和19.9%(P<0.01)。大豆植株R4～R8期氮积累量与产量呈极显著正相关(r=0.795**),提高结荚鼓粒期后大豆氮素积累量是增加大豆产量的关键。 相似文献
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Daniel Vázquez Andrés G. Berger Martha Cuniberti Carlos Bainotti Martha Zavariz de Miranda Pedro Luiz Scheeren Claudio Jobet Javier Zúñiga Graciela Cabrera Rubén Verges Roberto Javier Peña 《Journal of Cereal Science》2012
Wheat consumption is growing, with processors asking for wheat-based products showing better and more consistent quality. Genotype, environment and their interaction (G × E) play an important role in the final expression of quality attributes. An international research consortium was developed in order to evaluate the magnitude of genotype, environment and G × E effects on wheat quality of cultivars developed for different agro-ecological zones in Latin America. Genotypes released in Argentina, Brazil, Chile, Mexico, Paraguay and Uruguay, were cultivated in twenty different environments within the participating countries. Each environment was characterized for cultural practices, soil type and climatic conditions. Grain yield and analyses of test weight, protein, ash, gluten, Alveograph, Farinograph, Falling Number, SDS sedimentation and flour color were determined. Allelic variations of puroindolines and glutenins were determined in all the genotypes evaluated. Both puroindoline and gluten protein alleles corresponded to genotypes possessing medium to very good bread making quality. Large variability for most quality attributes evaluated was observed, with wider ranges in quality parameters across environments than among genotypes; even for parameters known to be largely determined by genotype. The importance of growing environment on grain quality was proved, suggesting that breeders’ quality objectives should be adapted to the targeted environments. 相似文献
18.
《Field Crops Research》2002,73(2-3):169-180
Drought frequently reduces grain yield of rainfed lowland rice. A series of experiments were conducted in drought-prone northeast Thailand to study the magnitude and consistency of yield responses of diverse, rainfed lowland rice genotypes to drought stress environments and to examine ways to identify genotypes that confer drought resistance. One hundred and twenty-eight genotypes were grown under non-stress and four different types of drought stress conditions. The relationship of genotypic variation in yield under drought conditions to genetic yield potential, flowering time and flowering delay, and to a drought response index (DRI) that removed the effect of potential yield and flowering time on yield under stress was examined.Drought stress that developed prior to flowering generally delayed the time of flowering of genotypes, and the delay in flowering was negatively associated with grain yield, fertile panicle percentage and filled grain percentage. Genotypes with a longer delay in flowering time had extracted more water during the early drought period, and as a consequence, had higher water deficits. They were consistently associated with a larger yield reduction under drought and in one experiment with a smaller DRI. Genotypes, however, responded differently to the different drought stress conditions and there was no consistency in the DRI estimates for the different genotypes across the drought stress experiments. The results indicate that with the use of irrigated-control and drought test environments, genotypes with drought resistance can be identified by using DRI or delay in flowering. However, selections will differ depending on the type of drought condition. The inconsistency of the estimates in DRI and flowering delay across different drought conditions reflects the nature of the large genotype-by-environment interactions observed for grain yield under various types of drought in rainfed lowland conditions. 相似文献
19.
不同育秧盘对机插双季稻株型与产量的影响 总被引：2，自引：0，他引：2
【目的】旨在阐明不同育秧盘对机插双季稻株型与产量的影响。【方法】以4个早、晚稻品种为材料,设置毯状盘(CK)、钵体盘(D1)和钵体毯状盘(D2)3种育秧盘试验,系统测定了不同育秧盘处理下早、晚稻植株形态特征与产量结构。【结果】1）不同秧盘处理秧苗素质表现为CK>D1>D2;机插时,D2处理下秧苗整体机插质量最优,表现在漂秧率、伤秧率和漏插率D2均优于CK,提高了栽插质量;2）D2处理下秧苗返青快,拔节期后分蘖快,孕穗期分蘖数D2>D1>CK,有效促进了茎蘖成穗,直接影响产量;从SPAD值看,早晚稻孕穗期时,D2处理下秧苗叶片SPAD值比D1处理平均高出3.2%,比CK处理平均高出9.2%,可有效促进光合作用,为增产提供了营养保障;3）产量数据显示,早晚稻均以D2处理产量最高,早稻分别比CK和D1增产13.04%和1.65%,晚稻分别增产30%和19%,平均比对照(CK)育秧机插增产20%;具体表现在D2处理叶片叶绿素含量高,有效穗数多,结实率和千粒重指标好。【结论】与毯状盘和钵体盘相比,钵体毯状盘可提高秧苗素质和产量,在江西双季稻生产中具有推广应用价值。 相似文献
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为培育具有高潜力的减肥增效油菜品种,以不同甘蓝型油菜种质资源为材料,通过两年三点的田间肥效试验,研究了它们对氮肥的响应特征及节氮增产潜力.以产量平均值为分界线将供试材料划分为4种类型:低氮高效型、双高效型、双低效型和高氮高效型.在高氮条件下,双高效型和高氮高效型材料具有16.96％～36.50％的节氮潜力和21.57％... 相似文献