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1.
T. Kaneko  W.S. Zhang  K. Ito  K. Takeda 《Euphytica》2001,121(3):225-228
The thermostability of β-amylase in 6752 lines of worldwide barley genetic resources were investigated. Most of the lines were classified into high (type A), medium (type B) , and low (type C) thermostability. Subsequently the geographical distribution of these types was clarified. About 90% of the East Asian (Japan, the Korean Peninsula, China) lines were type A. More than 95% of Ethiopian barley was type C. The thermostability types of varieties in the western areas (north Africa, southwest Asia, Turkey, Europe) consisted of types A, B and C. These results suggest that there is a clear geographical differentiation in β-amylase thermostability, especially in East Asia and Ethiopia. The phenotype characteristics of each thermostability type line reflected the geographical differentiation. Besides types A, B and C, we found new thermostability types, including such useful mutants as a β-amylase-less mutant and highly-thermostable mutants than type A in both China and Nepal. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

2.
M. Kihara    T. Kaneko  K. Ito 《Plant Breeding》1998,117(5):425-428
To investigate variation in the thermostability of β-amylase among varieties of barley, Hordeum vulgare L., crude enzyme was extracted from the seeds, and the relative remaining activity was calculated after heat treatment. Our results indicated that the varieties tested were divided into three groups (types A, B and C). All the latest Japanese malting varieties showed high themostability (type A), while European, North American and Australian varieties showed intermediate (type B) or low thermostability (type C). Isoelectric focusing (IEF) of β-amylase was also investigated. Type B varieties divided into two subtypes (types B1 and B2) based on two different IEF patterns (types I and II), whereas those of types A and C showed only one IEF pattern (type II). We also examined their thermostability in the varieties based on the pedigrees of the Japanese malting barley. Our results indicated that the thermostability of β-amylase had a close relationship to fermentability for the production of beer. This fact suggests that the thermostability of β-amylase has a significant influence on the malting quality of barley.  相似文献   

3.
A cleaved amplified polymorphic sequence marker was used to detect the alleles Bmy‐Sd2H and Bmy‐Sd3 identifying highly thermostable isoforms of the enzyme b‐amylase, which improves fermentability during brewing. Among the 889 accessions of barley (Hordeum vulgare) investigated, and two accessions of H. spontaneum a total of 166 accessions were identified carrying the superior b‐amylase alleles. These thermostable alleles of b‐amylase were most frequently observed in six‐rowed varieties originating from Asia, especially Japan, with 61.9% of the accessions from Asia carrying the alleles of interest. Additional six‐rowed barleys carrying the relevant alleles were identified among accessions from America, Africa and the Near East. In the European varieties, the percentage of accessions with the alleles of interest was 5.1% with a strong predominance in two‐rowed spring barleys. A pedigree analysis identified the cross ‘Binder’ x ‘Gull’ as the main source of the thermostable b‐amylase alleles in European varieties. The data suggest that an improvement of malting quality in barley could be achieved by introduction of the Bmy1‐Sd2H and Bmy1‐Sd3 alleles into the European breeding programmes.  相似文献   

4.
A wide variation in resistance to blast disease caused by Magnaporthe grisea (Hebert) Barr. ( Rossman et al. 1992 ) was found using 922 rice ( Oryza sativa L.) varieties collected mainly from Asia. These were classified into six varietal groups, termed clusters A–F, according to Ward's hierarchical cluster analysis, based on the reaction pattern to 20 standard differential blast isolates from the Philippines. The most susceptible two clusters, B and C, dominated in varieties from the Far East (Japan). Varieties from East Asia and Southeast Asia occurred less frequently in B and C clusters than those of Japan, and more frequently in E and F clusters, which were the most resistant of the cluster groups. Varieties from South Asia showed the widest variation, occurring in all clusters but less frequently in cluster B. The cluster B varieties dominated in Japan and showed a high frequency of isozyme type VI, corresponding to Japonica type. In contrast, the frequency of cluster B was low in the groups with isozyme types I, II, III and V, which dominated in South Asia. Isozyme type I corresponds to Indica type varieties. The distribution of resistance corresponded to the geographical distribution of rice varieties and might be related to differentiation into Indica and Japonica types. These findings will provide useful information for understanding the variation in blast resistance at the global level.  相似文献   

5.
T. Kaneko  M. Kihara  K. Ito 《Plant Breeding》2000,119(3):197-201
β‐Amylase thermostability is one of the major factors affecting fermentability in the brewing process; consequently, it could be used as a selection marker for the trait. In order to clarify what controls its thermostability, the linkage analysis of β‐amylase thermostability and its genotype as restriction fragment length polymorphism patterns was performed in three cross populations. Then, β‐amylase cDNAs cloned from the three varieties which had a different thermostability type were expressed in Escherichia coli. According to the results of the linkage analysis and gene expression test, it was concluded that β‐amylase thermostability resulted from a difference in its structural gene. Furthermore, to construct an STS marker for the gene, the gDNA sequences of β‐amylase were compared among the three varieties, which had different thermostabilities. Although there were many differences in the intron sequence, few nucleotides differed in the exon region. Based on the variation in the intron region, a sequence‐tagged‐site marker was constructed to detect β‐amylase genotypes in breeding material.  相似文献   

6.
Strong enzymatic activities in the germinating barley grain, together with protein and starch content, are crucial for high extraction values in the resulting malt and, therefore, barley malting quality. The efficient characterization of registered barley cultivars and genetic resources with respect to one of the relevant thermostability enzymes (β‐amylase) is an essential requirement. The template‐directed dye‐terminator incorporation (TDI) assay: based on flourescence resonance energy transfer (TDI‐FRET) ( Chen et al. 1995 ) was used to detect single nucleotide polymorphisms (SNPs) in the β‐amylase coding sequence resulting in low (Sd2L), intermediate (Sd1) and high (Sd2H and Sd3) thermostability enzyme across 84 Czech barley cultivars and genetic resources used over a period of time in the Czech Republic. The incidence of different alleles has changed during the last 100 years. Also the new resources with high thermostabile β‐amylase were identified. They can be used effectively to breed for malting quality improvement.  相似文献   

7.
为了明确大麦籽粒灌浆期β-淀粉酶动态与气象因子的内在联系,对两年间5个大麦品种籽粒灌浆期β-淀粉酶动态与气象因子进行了相关分析。结果表明,大麦籽粒灌浆期的β-淀粉酶活性呈升–降–升的动态过程,在成熟期达到最大值。偏相关分析和多元回归分析表明,大麦籽粒灌浆期β-淀粉酶活性与总积温呈极显著正相关,与总日照时数和日均日照时数的互作呈显著相关,与日均温、日均日照时数呈显著负相关,与总积温和日均温的互作、总雨量和日均日照时数互作呈极显著负相关,偏相关系数从大到小依次为总积温、总雨量和日均日照时数交互作用、总积温和日均温交互作用、总日照时数和日均日照时数交互作用、日均日照时数、日均温。  相似文献   

8.
耐热α-淀粉酶被广泛用于食品等诸多行业,本研究从中国北方高温堆肥分离的枯草芽孢杆菌FS321中克隆了一中度耐热α-淀粉酶基因,并实现在大肠杆菌BL21(DE3)中的表达。通过PCR技术克隆Bacillus subtilis FS321的α-淀粉酶编码基因(BSA),该基因全长1980 bp。并构建重组表达质粒pET-28a/BSA,转化大肠杆菌E. coli BL21(DE3),经IPTG诱导表达,SDS-PAGE检测到大小约为73.0 kDa的重组融合蛋白,可溶性淀粉平板检测结果表明BSA在大肠杆菌中实现了有效表达。该重组α-淀粉酶的最适反应温度为50℃,最适反应pH为7.5。  相似文献   

9.
为了了解苎麻与野生近缘种的系统学关系,更有效利用野生苎麻资源,通过细胞学观察和分子标记证据,对中国苎麻与其24个野生近缘类群进行了系统学分析。细胞学结果表明,苎麻间期核形态属于田中分类体系的前染色体型,而其野生近缘种分别属于前染色体型和分散型;苎麻和23个野生近缘物种(其中15个类群的染色体数目为首次报道)中,19个为二倍体(2n=28),而大叶苎麻组3个类群为三倍体(2n=42),1个为四倍体(2n=56),1个为五倍体(2n=70)。ITS序列和trnL-F序列分析表明,苎麻属可分成A(含A1和A2亚分支)、B(含B1和B2亚分支)和C 3个基本分支。根据分析结果本文提出苎麻属的两条演化路线: (1)前染色体型进化路线A1→A2,即腋球苎麻组→苎麻组;(2)分散型进化路线B→C,即腋球苎麻组→帚序苎麻组→序叶苎麻组→大叶苎麻组。  相似文献   

10.
Germplasms consisting of 64 wild barley accessions (Hordeum vulgare ssp. spontaneum) were examined for polymorphisms in α‐amylase using both isoelectric focusing (IEF) and thermostability assays. Wide variation was found for the high pI α‐amylase with 20 IEF band patterns identified. Enzyme activity and thermostability assays showed large differences among α‐amylase isoenzymes. Two wild accessions Tel‐Shoket CPI 77146‐32 and Afiq CPI 77128‐41 showed superior enzyme activity and thermostability compared with commercial varieties such as ‘Baudin’, ‘Flagship’ or ‘Navigator’. The functionality of the Tel‐Shoket allele was validated in backcross lines with ‘Flagship’ as the recurrent parent. The Tel‐Shoket allele at the amy1 locus increased α‐amylase thermostability at 75°C by 8.4% and α‐amylase activity in kilned malt by 18.7%. The introgression of the wild allele also led to significant improvements in fermentability, hot water extract and viscosity. Gene sequencing showed that there are three single nucleotide polymorphisms in the Tel‐Shoket amy1 sequence, which can be used as diagnostic markers for the selection of this allele in breeding programmes.  相似文献   

11.
以平贝母为供试材料,研究了组培平贝母培养过程中不同发育时期培养体的淀粉酶同工酶及其活力的变化,可为进一步深入研究贝母器官发生机理和以后的分子研究提供参考。结果表明:在发育过程中各培养体的淀粉酶同工酶在Rf=0.167处产生了平贝母α-淀粉酶的特征性酶带,在Rf=0.250时,4个时期都有浅蓝色的R-淀粉酶的表达;而β-淀粉酶酶带在小鳞茎膨大阶段进行表达,而在其他3个时期没有该酶的表达。在淀粉酶活力方面,培养体内总淀粉酶活力整体呈下降-上升-下降的趋势,不同发育时期的α-淀粉酶变化趋势与总淀粉酶变化趋势相似,其活力始终高于β-淀粉酶,推测α-淀粉酶在组培平贝母不同发育时期培养体的淀粉代谢中作用比较重要。  相似文献   

12.
To understand the diversity in the thermostability of the seed lipoxygenase‐1 (LOX‐1), 1040 cultivars of worldwide barley (Hordeum vulgare ssp. vulgare) genetic resources were investigated. The relative thermostability of LOX‐1 (LOX‐RTS) in these lines showed a bimodal frequency distribution and these lines were categorized into the high and low thermostability types (H‐type and L‐type, respectively). The H‐type lines predominated in the wild progenitor, ssp. spontaneum. The geographical distribution of these types in the cultivars was surveyed. The frequencies of the H‐ and L‐types were almost equal to one another in southwestern Asia. The occurrence of the H‐type predominated in eastern Asia and Africa, whereas in Europe and Turkey, the L‐type did. The predominance of the L‐type in Europe and Turkey can be understood through the hypothesis that the Fertile Crescent domestication contributed the majority of diversity in Europe. The uneven geographical distribution of the LOX‐1 thermostability types in the cultivars may reflect a polyphyletic origin of barley.  相似文献   

13.
CHE饲料发酵过程中淀粉酶活力的在线监测   总被引:1,自引:1,他引:0  
淀粉酶(包括α-淀粉酶和β-淀粉酶)是饲料复合酶制剂中最主要的酶之一。本文对CHE饲料中的α-淀粉酶及淀粉酶全酶进行了提取并进行了活性测定。结果表明α-淀粉酶和β-淀粉酶的最适温度分别为52℃和45℃。α-淀粉酶酶活力最大为5.6352ug/min, β-淀粉酶酶活力最大为1.0931ug/min。  相似文献   

14.
Stripe rust, caused by Puccinia striiformis, has been an important disease of wheat, barley, rye, triticale and certain graminaceous hosts for centuries. The significance of the disease on cultivated cereals has waxed and waned according to the vagaries of climate, inoculum levels and susceptible varieties. A progressive understanding of pathogen biology has revealed levels of specialisation between and within host groups, and these had varying impacts on the hosts concerned. The most economically important form is P. striiformis f. sp. tritici (Pst), the causal pathogen of stripe (yellow) rust of wheat, which is the major focus of this paper. The recent discovery of the perfect stage of Pst on Berberis spp. will encourage further work to uncover the potential importance of the sexual stage in pathogen biology in regions where Berberis spp. occur. A review of the evolution of pathotypes within Pst over the past 50 years reveals recurrent pandemics emanating from a combination of specific virulence in the pathogen population, wide scale cultivation of genetically similar varieties, and agronomic practices that led to high yield potential. When these factors operate in concert, regional stripe rust epidemics have proven to be dramatic, extensive and serious in terms of the magnitude of losses and the economic hardships endured. A review of these epidemics suggests that little progress has been made in containing the worst effects of epidemics. The current status of stripe rust was gauged from a survey of 25 pathologists and breeders directly associated with the disease. It was evident that Pst remains a significant threat in the majority of wheat growing regions of the world with potential to inflict regular regional crop losses ranging from 0.1 to 5%, with rare events giving losses of 5–25%. Regions with current vulnerability include the USA (particularly Pacific North West), East Asia (China north-west and south-west), South Asia (India, Pakistan, Nepal), Oceania (Australia, New Zealand), East Africa (Ethiopia, Kenya), the Arabian Peninsula (Yemen) and Western Europe (east England). The resources deployed to contain the worst effects of Pst will need to find a balance between training a new generation of breeders and pathologists in host-pathogen genetics, and an investment in infrastructure in IARCs and NARs.  相似文献   

15.
旨在明确来自亚洲、欧洲、非洲、北美洲、南美洲共441份水稻种质的恢保关系和强恢种质分布地区,为高效选育恢复系、保持系提供优异亲本。用野败型细胞质雄性不育系‘明218A’为母本与外引种质测交配制441份测验种。以自然结实率为指标,鉴别恢保类型。鉴定出恢复型种质53份,保持型种质43份,半恢半保型种质333份。分析53份恢复种质的分布地区,结果表明来源于亚洲国家(地区)种质最多,达到了33份,占恢复种质的比例为62.3%;筛选出美国强恢种质6份,占来源美国种质31.6%;来源于欧洲种质仅2份,占来源于欧洲种质的比例为5%,欧洲恢复种质相对较少。对53份强恢种质测交F1与测交父本7个重要性状均值进行相关分析,其中株高(r=0.97**)、千粒重(r=0.934**)和穗长(r=0.747**)3个性状达极显著相关,而其余的4个性状的相关不显著。相关程度的大小顺序为:株高>千粒重>穗长>有效穗>穗总粒数>穗实粒数>自然结实率。野败型不育系强恢的种质5大洲都有分布,主要集中在亚洲的东亚、南亚、东南亚地区以及美国。恢复系的株高、千粒重以及穗长对杂交种F1的影响较大。  相似文献   

16.
Hypocotyl saponin composition of 1,198 accessions of wild soybean (Glycine soja) collected from China, Korea, Japan and Russia Far East was analyzed by thin-layer chromatography to determine polymorphic variation and geographical distribution. Eight common distinguishable saponin phenotypes were identified: Aa, Ab, AaBc, AbBc, Aa+α, Ab+α, AaBc+α and AbBc+α. The latter four +α type were new. All eight types were identified in China. Type Ab+α was absent in Korea. Types Ab+α and AbBc+α, and Aa+α and Ab+α were not identified in Japan and Russia far east, respectively. Six new triterpene saponins were detected in +α type via LC-PDA/MS/MS analyses. They were, tentatively, designated as H-αg, H-αa, I-αg, I-αa, J-αg and J-αa. These saponins were inherited together by a single dominant allele. A gene symbol Sg-6 was assigned. Hence, the new saponins were collectively named as Sg-6 saponins. The frequency of Sg-6 allele was 17.6 % in Chinese, 10.0 % in Korean and 1.0 % in Japanese wild soybean. The wild soybeans having Sg-6 saponins can be utilized in soybean breeding programs as well as in saponin biosynthesis studies in soybean.  相似文献   

17.
以11份Wx蛋白全部缺失类型(糯性),11份Wx蛋白部分缺失类型(非糯性)和大面积推广品种扬麦158、扬麦12(非糯性)为试验材料,以白皮品种豫麦47为穗发芽对照,研究了它们的穗发芽特性、α-淀粉酶活性和籽粒可溶性糖含量。结果表明,糯小麦的穗发芽率和籽粒可溶性糖含量均极显著高于非糯小麦,而α-淀粉酶活性与非糯小麦差异不显著。α-淀粉酶活性高是非糯小麦穗发芽的原因之一,两者呈指数关系,y=0.4145e0.4864x(R2=0.3513*);对于糯小麦,籽粒可溶性糖含量高可能是其穗发芽严重的诱导因素,两者亦呈指数关系,y=0.0001e2.5599x(R2=0.5338**)。  相似文献   

18.
Although economically interdependent, political rivalry between Japan and China have brought about the inability of the Association of Southeast Asian Nations Plus Three (APT) process to transform itself into an East Asia Summit (EAS) as originally envisioned. The existence of the APT and the EAS as two separate entities not only reflected the politico‐security rivalry between the two neighbours but more importantly affected the direction and progress of East Asian regionalism as a whole. Aiming to provide a historical account of the EAS process and examine Japan's role in the development of the EAS framework, this paper argues that Japan has put greater attention on the EAS and made numerous unilateral initiatives to develop it. While Japan does not seek ultimate power, it considers the EAS as an excellent opportunity to: (i) raise its influence in the region vis‐à‐vis China; (ii) elevate the status of the EAS in region‐building and (iii) check Chinese advances by fulfilling its long‐held policy of having other Asia Pacific countries, primarily Australia and New Zealand, join. Nevertheless, the decision to expand the EAS to include the USA and Russia will have some adverse effects on Japan's unilateral ambitions and the furtherance of regionalisation processes.  相似文献   

19.
为找出不同类型籼粳杂交稻在品质表现上存在差距的原因, 以18个早熟晚粳籼粳杂交稻品种(品系)为材料, 从中筛选出产量与蒸煮食味品质具有代表性的3种类型(A类高产优质型, B类高产不优质型, C类低产不优质型)。2年中A类和B类的平均产量分别较C类高22.66%和22.26%, 其高产的原因主要是具有较高的单位面积穗数和每穗粒数。A类的糙米率和整精米率分别比B和C类高1.9%~2.5%和13.9%~22.7%。与A类相比, B类和C类的垩白率和垩白度分别高43.3%~47.5%和64.5%~71.4%。B和 C类的平均直链淀粉含量较A类分别高31.7%、33.0%。A类平均胶稠度较B和C类分别高4.0%、4.5%, A类品种的峰值粘黏度和崩解值最高, 消减值最低, 蛋白质含量3种类型无显著性差异。相关性分析表明, 灌浆结实期温度与加工品质、外观品质、蒸煮食味品质呈负相关。籼粳杂交稻优质的获得, 除品种遗传因素外, 可通过合理的播期或栽培管理调节, 使水稻灌浆结实期处于相对较低的温度下则有利于其稻米外观品质和蒸煮食味品质的同步提高或改良。  相似文献   

20.
Abstract: Will future transportation carbon dioxide (CO2) emissions per capita in Asia Pacific economies follow historical trends of the now developed world? Evidence to date is inconclusive. A comparison at similar income levels (purchasing power parity) between recent emissions in Asia Pacific countries and historical emissions in developed countries suggests diverging patterns. (A) High‐income Asia economies (Japan, Hong Kong and Singapore –‘low emitters’) exhibit lower emissions than a selected sample of seven developed countries (United States, Australia, France, the Netherlands, Italy, Sweden and United Kingdom). (B) Another set of Asian countries (South Korea and Taiwan –‘medium emitters’) follow the emissions trends of European countries, which are lower than those of Australia and the United States. (C) A third Asian group (Malaysia and Thailand –‘high emitters’) exhibit emission trends comparable to that of Australia. We describe these trends, examine their causes and extrapolate likely futures for emissions in low‐income Asia Pacific economies (China, Indonesia, Philippines and Vietnam). Although such predictions are speculative, the available evidence suggests that road CO2 emissions for Indonesia, the Philippines and Vietnam will follow those of the third group (high emitters), while those for China may follow either Group B or Group C.  相似文献   

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