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911.
Substituting Ability of Individual Barley Chromosomes for Wheat Chromosomes 1. Substitutions Involving Barley Chromosomes 1, 3 and 6 总被引:1,自引:0,他引:1
In order to determine the genetic relatedness of individual barley chromosomes to wheat chromosomes, ‘Betzes’ barley chromosomes 1, 3 and 6 were substituted for individual ‘Chinese Spring’ wheat chromosomes of homoeologous groups 7, 3 and 6, respectively. The substitution status of these lines has been confirmed using isozyme selective markers, chromosome pairing behaviour in F1 hybrids between the substitution lines and the appropriate double ditelocentric stocks of wheat, and hybridization of cDNA probes to the genomic DNA digests of these substitution lines. Each of the three barley chromosomes provided genetic compensation for the wheat chromosomes they replaced in the substitution plants. From the basis of this compensation with respect to plant vigour and fertility, barley chromosomes 1, 3 and 6 have been designated 7H, 3H and 6H. 相似文献
912.
从云南、四川两省9个采样地共收集31个暗褐网柄牛肝菌(Phlebopus portentosus)子实体,通过组织分离获得菌株,分别利用固体、液体培养基培养菌丝体,对其进行酯酶同工酶分析,通过酶谱聚类分析研究分离菌株的遗传多样性。结果表明,固体培养的菌丝体共检出10个酯酶同工酶条带、21种酶谱类型,每个菌株具有2条~5条同工酶条带;液体培养菌丝体共检出11个同工酶条带、23种酶谱类型,每个菌株具有2条~6条同工酶条带;2种培养方式下所有菌株均检出一条相对迁移率R_f=0.13、相对分子质量为136 kDa的同工酶条带;不同培养方式相同菌株的酯酶同工酶酶谱存在较大差异。在遗传距离为0.220时,固体培养菌丝体的酯酶同工酶酶谱聚为9类,液体培养的聚为7类;在遗传距离为0.300时,2种培养方式的酶谱均聚为4类;聚类结果与地理来源无相关性。暗褐网柄牛肝菌具有丰富的遗传多样性,为后续种质资源保护、优良菌株筛选和种性鉴定等工作提供参考。 相似文献
913.
Isozyme electrophoregrams of sixteen enzymes in five tissues of cassava (Manihot esculenta
Crantz) varieties 总被引:1,自引:0,他引:1
Summary Methodology, based on starch and polyacrylamide gel electrophoresis, was developed for determining isozyme electrophoregrams (patterns) of 16 enzymes of cassava (Manihot esculenta
Grantz) varieties as potential genotype markers. Extracts of five different tissues (root, stem, leaf, petiole and bud) were examined. In general, the nodal portions of the shoots gave isozyme patterns with the largest number of bands. Petiole extracts gave similar results but bud extracts gave poor patterns. The limited number of varieties that were examined could be distinguished by sequential classification on the basis of the isozyme patterns of acid phosphatase, esterase, glutamate oxaloacetase transaminase and phosphoglucoisomerase.Joint publication of the Centro Internacional de Agricultura Tropical and the Department of Plant Science (No. 716), University of Manitoba. Presented in part at the 2nd International Symposium on Biochemical Approaches to Identification of Cultivars and Evaluation of Their Properties, 5–9 May, 1985, Braunschweig, West Germany. 相似文献
914.
Summary Isozyme variation was studied in 1,417 cultivars and wild forms of taro collected in Asia and Oceania. Seven polymorphic enzyme systems (MDH, IDH, PGI, 6-PGD, ME, SkDH, and ADH) revealed 143 isozyme phenotypes, or zymotypes, each uniquely characterized by the presence or absence of 56 electromorphs. Results showed greater isozyme variation in Asia than in Oceania, with Indonesia being the area of greatest diversity. No correlations were found between zymotypes and morphotypes or ploidy levels (as described by other investigators). Multivariate analyses of the isozyme data indicated that the majority of the Indonesian cultivars were different from the Philippine and Oceanian taro cultivars. Oceanian cultivars constituted a continuum of clusters and are thought to have originated from a narrow genetic base introduced from Indonesia. If taro breeding is to have any future in Oceania, it is important to exchange genotypes to broaden the base of existing breeding programmes. 相似文献
915.
A. M. Chevre R. Delourme F. Eber E. Margale C. F. Quiros P. Arus 《Plant Breeding》1995,114(6):473-480
General criteria for the assignment of names to enzyme systems, regions of activity, isozyme loci and allozymes have been lacking in crucifer species. This paper proposes a standard nomenclature for seven isozyme systems in the three diploid species of U's triangle: Brassica nigra, B. oleracea and B. campestris. Gel/electrode buffers, which provided the best resolution for seven isozyme systems, acid phosphatase (APS), aconitase (ACO), leucine aminopeptidase (LAP), 6-phosphogluconate dehydrogenase (6 PGD), phosphoglucoisomerase (PGI), phosphoglucomutase (PGM), and triosephosphate isomerase (TPI), were proposed as standards. Isozyme genetic analysis was determined for B. oleracea and B. campestris from previous studies and by segregation of selfed progenies of heterozygous B. nigra plants. Several populations were studied and 148 allozymes at the 18 loci observed were described for the three species. Their relative mobility was studied using a pure line of oilseed rape as reference. The comparison of the different alleles within and between the species is discussed. 相似文献
916.
Geographical differentiation and phylogenetic relationships of Asian taros, Colocasia esculenta (L.) Schott, and related species were analyzed by random amplified polymorphic DNA (RAPD) and isozymes of 13 enzyme systems
with special interest in the accessions from the Yunnan area of China, which supposedly has served the secondary center of
taro diversification and dispersal into the temperate Far East Asia. The RAPD analysis was found to be better suited for detecting
genetic differences within taros and among its related species. However, both RAPD and isozyme analyses estimated quite similar
genetic relationships within taros and between related species. Genetic differentiation was evident in the taro accessions
of Nepal, Yunnan and other Asian areas; but, phylogenetic relationships between the differentiated taro groups were not clearly
determined. When taro cultivation was introduced to a new area, only a small fraction of genetic variability in heterogeneous
taro populations was transferred possibly causing random differentiation among locally adapted taro populations. Some of the
Yunnan and Japanese accessions were found to be direct descendants of the common triploid population. Further analysis on
taros from the eastern China and Korea is necessary to clarify the Yunnan's role in taro diversification and dispersal. The
significant local differentiation in Asian taros was clearly demonstrated by RAPD and isozyme analyses in this study, and
the results of this study will serve as a base to establish evolutionary and genetic relationships among Asian taros.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
917.
The segregation of isozyme genetic markers was studied on embryos arising from isolated microspore cultures in live rapeseed F1 hybrid genotypes. Out of the ten isozyme genes considered, live (Aco-1, Aco-3, Lp-1, Pgm-3, Tpi-1) did not segregate according to expected Mendelian ratios in at least two F1 crosses. F2 plants, generated from the same hybrids, included in the analysis, were tree of segregation distortions. Linkage analysis between each segregating enzyme locus in each progeny revealed independance between these markers. In this paper, the results of the linkage analysis as well as the origins of the distortions are discussed. The existence of androgenic embryogenesis genes may be responsible for the abnormal segregations of the five isozyme genes. 相似文献
918.
采用聚丙烯酰胺凝胶垂直板电泳技术对苜蓿雄性不育系及其回交后代进行过氧化物酶(POD)、酯酶(EST)同工酶分析。结果表明:(1)苜蓿雄性不育系及其回交后代叶的POD同工酶在现蕾期和开花期的酶带数较返青期多。返青期的酶活性较现蕾期和开花期强;MS-4及其回交后代叶的EST同工酶活性变化规律与POD同工酶谱表现相似;(2)在花发育的不同时期,花蕾为绿色时期时的POD同工酶酶活性最强,MS-4及其回交后代小花的EST同_T-酶酶带数较叶的多。刚开过的小花EST同工酶酶活性最强,F1、BC1代不育株都出现了母本MS-4所具有的POD、EST特征酶带;(3)从MS-4回交后代中所选育的不育株的POD和EST同工酶谱明显偏向于轮回亲本MS-4,说明通过回交使MS-4的某些性状在回交后代中进一步得到表现,因此,可以初步认定原不育系Ms4的不育性是可遗传的。 相似文献
919.
Ryuji Ishikawa Yuko Harata Yasunori Tuchimine Mineo Senda Shinji Akada Takeo Harada Minoru Niizeki 《Euphytica》1997,98(3):197-203
Two rice ecotypes, the so-called lowland and upland populations, which carry different isozyme genotypes mostly at a single
locus, are cultivated in Japan. The aim of this study was to examine the origin and the mechanism for keeping these genetic
differences. The upland population is cultivated in upland fields and carries a different allele for a particular isozyme
gene, Pgd-1, which has never been found in the lowland population. RFLP markers showed a weak trend for genetic differentiation
between the two ecotypes. On the other hand, morphological, and physiological traits showed marked differences between the
two ecotypes. Furthermore, based on the genotypic difference, two Japonica subgroups are defined in the upland population.
Subgroup I is the minor group and carries key lowland characters, including the genotype for PGD. Subgroup II carries different
traits and the genotype for PGD of the alternative subgroup. As an allelic difference for Pgd-1 is known to occur between
the two ecospecies, Tropical (Tr) and Temperate (Tm) Japonicas, upland cultivars can be classified by diagnostic characters
which distinguish a variety into Tr or Tm type. The upland population consists of three types of cultivars, Tr-, Tm- and intermediate-type.
In contrast, the lowland population consists of a uniform Tm type Japonicas. As Japanese upland cultivars still have an isozyme
allele specific to the Tr type, the upland population has a rather complex constitution which is presumably now being introgressed
by lowland genetic material, but still represents a major difference at some genetic levels. Upland rice carries several stress-resistant
genes which would be useful for lowland rice breeding. The genetic difference would be efficient for tagging upland specific
traits by upland specific genetic markers.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
920.
Marie-Paule Ottaviani Charlotte H. Hänisch ten Cate Lous van Vloten-Doting 《Plant Breeding》1992,109(2):89-96
The linkage relationship between eighteen isozyme loci and the morphological markers hypocotyl colour (R-r), monogerm character (M-m), pollen fertility (X) and stem fasciation (Verb.) are tested. Three linkage groups could be set up, involving all morphological marker loci and eight of the isozyme loci. Est-2, R-r, Fdp-2, Got2 and Icd-1 belong to linkage group I, linkage group II includes the loci Fas-fas M-m, Est-3 and Aco-1, linkage group III contains the loci X, Mdh-1 and Est-5. When analysing the inheritance of isozymes and RFLPs, deviations are usually found in some lines from the expected frequencies of a 3 : 1 or 1 : 2 : 1 segregation at single marker loci. In many cases these data can still be used for the estimation of recombination values with linked loci under the control of selection. Procedures to estimate linkage in such cases are given and applied to experimental data in Beta vulgaris. 相似文献