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101.
阐述了燕麦中β-葡聚糖的含量及相对分子质量测定方法的国内外研究动态和研究成果,其中包括对β-葡聚糖含量的测定方法(酶测定法、荧光法、高效液相色谱法、刚果红分光光度比色法)的研究,以及对β-葡聚糖相对分子质量测定方法(高效凝胶色谱法、凝胶色谱法、高效液相色谱法)的研究。 相似文献
102.
Identification of a RAPD marker linked to a brown planthopper resistance gene in rice 总被引:12,自引:0,他引:12
We report the tagging of a brown planthopper (BPH) resistance gene (Bph–1) in rice using RAPD and RFLP markers. The Korean
rice variety ‘Gayabyeo’ has dominant duplicate genes including Bph–1 conferring resistance to biotype 1 of BPH. Bulked segregant
RAPD analysis was employed for rapid identification of DNA markers linked to resistance genes. For tagging these two genes,
an F2F3 population from a ‘Gayabyeo’ × ‘Nagdongbyeo’ cross was developed and evaluated for BPH resistance. Three bulked DNAs
from two groups of homozygous BPH resistant (each for Bph–1 and the other unknown gene) and homozygous susceptible F2 plants
were analyzed by RAPD using 140 random oligomers. One primer, OPD–7 yielded a 700-bp fragment that was present in Gayabyeo
and resistant F2 plants (homozygous for Bph-1 locus) but absent in Nagdongbyeo and susceptible F2 plants. Cosegregation of
this marker with Bph-1 was verified using an F2 population segregating for Bph-1. Chromosomal regions surrounding the Bph-1
were examined with additional RFLP and microsatellite markers on chromosome 12 to define the location of the RAPD marker and
Bph-1. Use of this RAPD marker could facilitate early selection of resistant lines for BPH.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
103.
104.
The genetic relationship between popping expansion volume and two yield components in popcorn using unconditional and conditional QTL analysis 总被引:2,自引:0,他引:2
Y. L. Li Y. B. Dong D. Q. Cui Y. Z. Wang Y. Y. Liu M. G. Wei X. H. Li 《Euphytica》2008,162(3):345-351
Popping expansion volume (PEV) is the most important quality trait in popcorn, while its germplasm is inferior to normal dent/flint
corn in yield. In this study, 259 F2:3 families, developed from the cross between a dent corn inbred Dan232 and a popcorn inbred N04, were evaluated for their PEV,
grain weight per plant (GWP) and 100-grain weight (100 GW) in two environments. The genetic relationship between PEV and GWP,
and 100 GW on individual gene loci were evaluated using unconditional and conditional QTL mapping methods. In total, five,
one and three unconditional QTL were identified for PEV, GWP, and 100 GW, respectively. The positive alleles of all QTL for
PEV were from N04, while positive alleles of all QTL for GWP and 100 GW were from Dan232. In conditional mapping, one and
two QTL failed to be detected, and all four additional QTL were detected. Nevertheless, three QTL were identified, which controlled
PEV independently from GWP/100 GW. They seemed to be potential candidates in popcorn breeding to increase PEV without decreasing
GWP/100 GW. The results suggested that for significantly correlated traits, the conditional QTL mapping method could be used
to dissect the genetic interrelationship between traits at the level of individual QTL, as well as reveal additional QTL that
were undetectable by unconditional mapping. 相似文献
105.
海岛棉(Gossypium barbadense)是世界上最重要的栽培棉种之一。海岛棉纤维品质优良,是优质棉的重要产源。为了研究海岛棉的遗传多样性,为海岛棉育种提供参考依据,从海岛棉遗传标准系中分离基因组来源的微卫星标记用于海岛棉遗传评价。采用两种方法分离微卫星标记,一是用ISSR (inter simple sequence repeat) 引物扩增Pima3-79,克隆测序后从中开发微卫星标记;二是利用简并引物扩增Pima3-79,克隆测序后从中开发微卫星标记。共挑选1 447个克隆,筛选出239个独立克隆。测序后得到214个单一序列,其中包含微卫星并可用于引物设计的序列70个,获得86对引物。86对引物用于扩增56个海岛棉材料和4个陆地棉材料,16对引物没有扩增,43对引物在所有材料中没有多态性;27对引物在海岛棉和陆地棉之间有多态性,19对引物在海岛棉中表现多态性。利用Jaccard相似系数和UPGMA方法进行聚类分析可以明显区分陆地棉和海岛棉,并且将海岛棉分为4类。14对引物在BC1群体中表现多态性,产生14个位点。9个位点整合到BC1连锁图的7个染色体上,4个位于A亚基因组,5个位于D亚基因组。海岛棉微卫星标记扩展了棉花微卫星标记,有助于海岛棉遗传多样性的研究,有利于棉花遗传图谱的进一步丰富。 相似文献
106.
Recent advances in molecular genetics of forest trees 总被引:3,自引:0,他引:3
M.R. Ahuja 《Euphytica》2001,121(2):173-195
The use of molecular markers has greatly enhanced our understanding of the genome structure of forest trees. Conifers, in
particular, have a relatively large genome, containing a very high proportion of repeated DNA, consisting of tandemly repetitive
and dispersed repetitive DNA sequences. The nature of highly conserved tandemly repetitive rRNA genes has been investigated
in a number of tree species, and their sites mapped on specific chromosomes by fluorescent in situ hybridization (FISH). Different families of retrotransposons (IFG, and TPE1) have been isolated and characterized from the dispersed repetitive DNA of pines. Genome maps have been constructed in a
number of forest tree genera: Pinus, Picea, Pseudotsuga, Cryptomeria, Taxus, Populus, and Eucalyptus. EST databases have been established from cDNA clones of pines and poplars. The structure and maternal or paternal modes
of inheritance of organelle genomes have been investigated in forest trees. Comparative mapping in conifers has shown that
gene families are conserved across genera. Due to lack of polyploidy in conifers, the evolution of this group of trees may
have occurred primarily by duplication and dispersal of genes, probably by retrotranspositions, to form complex gene families.
The evolution of angiosperm tree species has presumably involved both gene duplication as well as genome duplication (polyploidy).
Application of genetic engineering has shown that genes from phylogenetically unrelated organisms can be introduced and expressed
in trees, thus offering prospects of genetic improvement of forest trees.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
107.
Elongated glumes are present in thetetraploid wheat species T.polonicum, T. turanicum, T.durum convar. falcatum and in thehexaploid species T. petropavlovskyi.Inheritance of glume length was studiedwith the aim to map the respective lociusing wheat microsatellite markers. In T. polonicum and T. petropavlovskyiloci conferring long glume were mapped nearthe centromere on chromosome 7A. These twoloci are designated P-A
pol
1 andP-A
pet
1, respectively. It isshown that both are probably homoeoallelicto each other and to the P gene ofT. ispahanicum on chromosome 7B. The loci determining elongated glumes in T. turanicum and T. durum conv. falcatum are not homoeologous to the P loci in the centromeric region of thegroup 7 chromosomes. 相似文献
108.
棉花抗黄萎病基因的QTL定位 总被引:33,自引:14,他引:33
以高感黄萎病的陆地棉品种"邯郸208"与高抗黄萎病海岛棉品种"Pima90"的136个F2单株为作图群体,构建了一个包括17个连锁群、标记间平均间距18.61cM、全长1842.8cM的陆海种间分子标记遗传连锁图,该图约覆盖棉花基因组的36.8%。单因子方差分析和复合区间作图检测到与黄萎病抗性相关的3个QTL,分别位于第四连锁群和第七连锁群上,分别解释表型变异方差的15.39%、54.11%和57.18%。初步认为海岛棉"Pima90"对陆地棉"邯郸208"的黄萎病抗性由两个主效QTL和一个微效QTL共同控制。 相似文献
109.
Jonathan Mkumbira Linley Chiwona-Karltun Ulf Lagercrantz Nzola Meso Mahungu John Saka Albert Mhone Mpoko Bokanga Leon Brimer Urban Gullberg Hans Rosling 《Euphytica》2003,132(1):7-22
Cassava roots, a major food in Africa, contain cyanogenic glucosides that may cause toxic effects. Malawian women farmers
considered fields of seemingly similar cassava plants to be mixes of both ‘cool’ and ‘bitter’ cultivars. They regard roots
from ‘cool’ cultivars as non-toxic. Roots of ‘bitter’ were considered to require extensive traditional processing done by
women to be safe for consumption. But curiously, these women farmers preferred ‘bitter’ cultivars since toxicity confers protection
against theft, which was a serious threat to the food security of their families. We studied how well these farmers comprehend
the effects of genetic variations in cassava when dealing with cyanogenesis in this complex system. Using molecular markers
we show that most plants farmers identified as belonging to a particular named cultivar had a genotype typical of that cultivar.
Farmers' ethno-classification into ‘cool’ and ‘bitter’ cultivars corresponded to a genetic sub-division of the typical genotypes
of the most common cultivars, with four-fold higher cyanogenic glucoside levels in the bitter cultivars. Examining morphology,
farmers distinguished genotypes better than did the investigators when using a standard botanical key. Undoubtedly, these
women farmers grasp sufficiently the genetic diversity of cassava with regard to cyanogenesis to simultaneously benefit from
it and avoid its dangers. Consequently, acyanogenic cassava – the breeding of which is an announced good of some cassava genetic
improvement programmes – is not a priority to these farmers. Advances in molecular genetics can help improve food supply in
Africa by rapid micropropagation, marker assisted breeding and introduction of transgenic varieties, but can also help to
elucidate tropical small-scale farmers' needs and skills.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
110.
Assessment of EST- and genomic microsatellite markers for variety discrimination and genetic diversity studies in wheat 总被引:22,自引:0,他引:22
Fiona Leigh Vince Lea John Law Petra Wolters Wayne Powell Paolo Donini 《Euphytica》2003,133(3):359-366
It is likely that in the near future sequence information from sequencing programmes and EST libraries will generate an abundance
of genic microsatellite markers. This study is focused on the assessment of their likely impact and performance vis-à-vis
their genomic counterparts. Microsatellites from two sources were used to assess the genetic diversity in 56 old and new varieties
of bread wheat on the UK Recommended List. A set of 12 microsatellite markers generated from genomic libraries and 20 expressed
sequence tag (EST)-derived microsatellites were used in the study, and the performance of both marker sets assessed. The EST-derived
or genic microsatellites delivered fingerprints of superior quality, amplifying clear products with few stutter bands. Diversity
levels as revealed bygenic microsatellites are similar to the few published results. The PIC values for the genic markers
were generally lower than those calculated for the genomic microsatellites, though advantages of both marker classes for variety
identification applications are discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献