Gene Flow Analysis of Phytophthora porri Reveals a New Species: Phytophthora brassicae Sp. Nov.     

Willem A. Man in 't Veld  Arthur W.A.M. de Cock  Elena Ilieva  C. André Lévesque 《European journal of plant pathology / European Foundation for Plant Pathology》2002,108(1):51-62

Isozyme analysis and sequence analysis of the internal transcribed spacer regions (ITS-1 and ITS-2) and the 5.8S subunit of the ribosomal DNA gene repeat were used to examine whether isolates of Phytophthora porri from Allium and Brassica represent a single homogeneous species. Twenty-six strains of P. porri, 16 strains isolated from the genus Allium, and 10 strains isolated from the genus Brassica, were analyzed using malate dehydrogenase (MDH), isocitrate dehydrogenase (IDH) and lactate dehydrogenase (LDH), represented altogether by four putative loci (Mdh-2, Idh-1, Idh-2, and Ldh-2). Isozyme analysis revealed that strains isolated from Allium contained five private alleles at three isozyme loci (Ldh-2 ⁸³, Ldh-2 ¹⁰⁴, Idh-1 ¹⁰⁸, Idh-1 ¹¹², and Idh-2 ⁹⁸), whereas six different alleles were observed at four isozyme loci (Ldh-2 ⁸⁵, Ldh-2 ¹⁰⁰, Ldh-2 ¹¹⁴, Idh-1 ¹⁰⁰, Idh-2 ¹⁰⁰, and Mdh-2 ¹¹¹) in strains obtained from Brassica. The heterozygosity at the Ldh-2 locus, differing in allele composition, however, between strains from Allium and Brassica, was present in all strains, indicating that it is probably fixed. Sequence analysis of the ITS regions and the 5.8S subunit showed consistent differences between isolates from Allium and isolates from Brassica. Based on isozyme data, ITS sequence analysis and formerly published differences in restriction enzyme patterns of mitochondrial DNA, morphology and pathogenicity, it was concluded that the isolates of P. porri Foister did not represent a homogeneous species. Isolates from Brassica constitute a distinct species which is described here as P. brassicae sp. nov. It was inferred from isozyme patterns, which were in no case intermediate between the two species, that P. porri and P. brassicae do not hybridize and are reproductively isolated by barriers to gene flow.  相似文献   

Armillaria species on tea in Kenya identified using isozyme and DNA sequence comparisons   总被引：1，自引：0，他引：1  

E. Mwenje  B. D. Wingfield  M. P. A. Coetzee  H. Nemato  M. J. Wingfield 《Plant pathology》2006,55(3):343-350

The aim of this study was to identify seven Armillaria isolates obtained from diseased tea bushes in Kenya using pectic enzyme profiles, PCR-RFLP and IGS-I DNA sequence data. The combination of these identification methods confirmed the presence of three distinct Armillaria groups. One of these groups resembled Zimbabwean group I ( A. fuscipes ). The second group was phylogenetically closely related to A. mellea ssp. nipponica . The third group was different from all other African isolates examined, but had isozyme patterns, especially of pectin methylesterases (PMEs), similar to those of isolates related to A. mellea ssp. nipponica. Analyses of sequence data suggested that this group is phylogenetically closely related to A. hinnulea from Australia and New Zealand.  相似文献   

草鱼LDH同工酶比较酶学和免疫化学性质   总被引：5，自引：0，他引：5  

薛国雄  官平  张燕生  杨靖  赵淑慧  吴婷婷  夏德全 《水产学报》1992,16(4):357-364

本文以草鱼为材料,利用亲和层析法,从肌肉、心脏和肝脏中分离纯化了 LDH同工酶基因产物;LDH-A_4、B_4和C_4,并对其纯度,氨基酸组成以及动力学性质进行了比较分析,同时制取了A_4、B_4和C_4的相应抗体,利用抗原-抗体免疫吸附反应对一些淡水鱼类的LDH 酶谱进行了准确的鉴定。  相似文献   

Are cell redox or lactate dehydrogenase kinetics responsible for the absence of gluconeogenesis from lactate in sea raven,hepatocytes?     

Glen D. Foster  J. Zhang  T. W. Moon 《Fish physiology and biochemistry》1994,13(1):59-67

Previous studies have reported very low rates of gluconeogenesis from lactate in sea raven (Hemitripterus americanus) hepatocytes compared to other teleosts studied. This study examines whether hepatic cell redox or lactate dehydrogenase (LDH) characteristics may explain this observation. Sea raven hepatic optimal LDH activities (pyruvate reductase direction) were more than 40 times less compared with rainbow trout liver values (40 vs 1914 μmol·min⁻¹·g⁻¹ protein). The Km(lactate) was 9.24 and 0.86 mM for sea raven and trout hepatic LDH, but the Km(pyruvate) was similar between the two species (0.11 and 0.21 mM, respectively). These results suggested that sea raven liver LDH did not favour lactate use and was more indicative of the mammalian M-isozyme. Gel electrophoresis showed a predominant intermediate isozyme, with a small amount of the M-type LDH. Phosphoenolpyruvate carboxykinase (PEPCK) was localized to the mitochondrial compartment, while there was no apparent mitochondrial glutamate-oxaloacetate transaminase (GOT) activity. No in vitro lactate flux to glucose was found in untreated, 10 mM ethanol-treated, or 3 mM NH₄Cl-treated sea raven hepatocytes, although CO₂ production from lactate was decreased by ethanol and increased by NH₄Cl. These results provide evidence that cell redox does not limit gluconeogenesis from lactate, while low activities and the kinetic characteristics of LDH may partially explain the low lactate gluconeogenesis reported in sea raven hepatocytes. To whom correspondence should be addressed at University of Ottawa.  相似文献   

Meiotic and Isozymic Analyses of Tall Fescue × Giant Fescue Hybrids and Amphiploids1     

G. C. Eizenga  D. M. Burner  R. C. Buckner 《Plant Breeding》1990,104(3):202-211

The meiotic behavior of three tall fescue (Festuca arundinacea, 2n = 6x = 42) genotypes, giant fescue (F. gigantea, 2n = 6x = 42), and their reciprocal F₁ hybrids and C₁, amphiploids was evaluated to determine the parental genomic relationships. Isozyme banding patterns were used to confirm the parental identity of the hybrids and amphiploids. At meta-phase I, the parents had predominantly bivalent pairing. The hybrids had an average of 9.51 I, 16.02 II, 0.12 III, 0.02 IV, and the amphiploids had 2.17 I, 38.82 II, 0.60 III, 0.58 IV, 0.01 V—VIII. The prevalence of bivalent pairing in both hybrids and amphiploids suggested a homoeologous relationship between the six genomes, with four of the six being more closely related. Bivalent pairing in the amphiploids indicated genetic regulation of chromosome pairing. Zymograms were obtained for acid phosphatase (ACPH), alcohol dehydrogenase (ADH), glutamate oxaloacetate transaminase (GOT), malate dehydrogenase (MDH), 6-phosphogluconate dehydrogenase (6-PGD) and phosphoglucoisomerase (PGI). The three tall fescue and giant fescue parents had different zymograms for ACPH, MDH, 6-PGD and PGI; thus, the tall fescue parents of the hybrids and amphiploids could be determined based on the banding patterns of these four enzymes. Phenotypes were determined for ACPH-1, PGI-2 and 6-PGD-1. ACPH-1 may be used to follow the introgression of giant fescue chromatin into a certain tall fescue genotype.  相似文献   

不同剂量~(60)Co-γ射线对小麦、水稻幼苗生长的影响   总被引：9，自引：0，他引：9  

彭永康  张丰德 《华北农学报》1987,(1)

用10—30KR剂量~(60)CO—γ射线处理小麦中引15、St和水稻沪B干种子、幼苗生长期胚根、子叶发育受到明显抑制.对幼苗生长的影响后期(萌发5天后)比早期(开始萌发至萌发第5天)明显,芽鞘的发育对γ射线不敏感.过氧化物酶同工酶的分析结果表明,发育受抑的小麦St、水稻沪B胚根中各增加1—2条负极酶带;发育受抑的小麦中引15、St、水稻沪B子叶中,过氧化物酶同工酶没有产生变化,而从外部形态特征上看没有变化的中引15芽鞘中比对照多2条正极带.上述结果表明,经r射线照射后,植物外部形态特征的变化与内部过氧化物酶同工酶的变化并不完全相关.  相似文献   

Genetics of Five Seed Esterase Isozymes in Pearl Millet     

M. V. Subba  Rao  Y. Saideswara  Rao V. Manga 《Plant Breeding》1989,102(2):133-139

Inheritance and linkage relationships of pearl millet seed esterase isozymes were studied using; polyacrylamide dise: gel electrophoresis and α-naphthyl acetate as substrate. The Zone of enzyme activity was resolved into five bands. The presence of a band showed complete dominance over its absence. Each one of the bands (1 to 4) was under the control of a single gene. Band five was found to be controlled by three independent loci with duplicate gent action Loci for Est₁, Est₃ and Est₄ Were found to be linked. Est₂ Was independent of this linkage group.  相似文献   

Electrophoretic Analysis of Eleven Isozyme Systems and their Possible Use as Biochemical Markers in Breeding of Chicory (Cichorium intybus L.)     

P. Baes  P. Van  Cutsem 《Plant Breeding》1993,110(1):16-23

Polymorphism and ontogeny of 11 chicory (Cichorium intybus L.) enzymatic systems have been analyzed by native polyacrylamide gel electrophoresis, namely: leucine aminopeptidase, phosphoglucomutase, shikimate dehydrogenase, glutamate oxaloacetate transaminase, superoxide dismutase, isocitrate dehydrogenase, esterase, phosphorylase, glucose-6-phosphate dehydrogenase, 6-phos-phogluconate dehydrogenase and glucose phosphate isomerase. The use of these systems as biochemical markers is discussed.  相似文献   

Identification of tomato cultivars (Lycopersicon esculentum) by polyacrylamide isoelectric focusing     

Gisela Henn  A. W. H. Neitz  A. I. Louw 《Euphytica》1992,62(2):77-82

Summary Isozyme analyses have been used for the definitive identification of many plant cultivars, but not for cultivated tomatoes. Six isozyme systems, namely alcohol dehydrogenase, acid phosphatase, phosphoglucomutase, esterase, phosphoglucoisomerase and 6-phosphogluconate dehydrogenase of tomato seed extracts were resolved by isoelectric focusing on polyacrylamide gels with a narrow pH gradient. Nine alcohol dehydrogenase phenotypes were distinguished which, with three acid phosphatase phenotypes, identified twelve of the seventeen cultivars. Fewer differences were found for the other isozymes. Since this method could differentiate between breeding parents and their progeny it is concluded that further investigations are warranted.Abbreviations APS acid phosphatase - ADH alcohol dehydrogenase - EST esterase - IEF isoelectric focusing - PGI phosphoglucoisomerase - PGM phosphoglucomutase - 6-PGDH 6-phosphogluconate dehydrogenase - RFLP restriction fragment length polymorphism - VOPRI Vegetable and Ornamental Plant Research Institute  相似文献   

New Genetic Markers in a Wild Species of Beet (Beta nana Boiss. et Heldr.): Prospects for Utilization     

T. Nagamine  B. V. Ford-Lloyd   《Plant Breeding》1989,102(4):344-347

In a study of variation in 13 enzymes occurring in B. nana, unique and invariant phenotypes were found for five of these enzymes, when compared with a range of other wild and cultivated beets. In similar comparisons unique alleles were found in B. nana for two other enzyme loci. For the remaining six enzymes B. nana was found to have variation and alleles which were common to other forms of beet. It is concluded that reliable markers for B. nana exist, and that this species represents a source of novel genes for sugar beet breeding.  相似文献