Inheritance of isozymes in peach x Prunus kansuensis and peach x Prunus davidiana hybrids

Summary Isozyme variation and inheritance were investigated with starch gel electrophoresis in peach (Prunus persica L. Batsch) x P. kansuensis Rehd. and peach x P. davidiana (Carr.) Franch. interspecific hybrids. Of five enzyme systems surveyed for polymorphism, four systems were identified as polymorphic [isocitrate dehydrogenase (IDH, EC 1.1.1.41), phosphoglucomutase (PGM, EC 2.7.5.1), aspartate aminotransferase (AAT, EC 2.6.1.1), and 6 phosphogluconate dehydrogenase (PGD, EC 1.1.1.44)] and may be useful as genetic markers in future cultivar and rootstock development. Analysis of progenies segregating for pairs of loci suggests a possible linkage between the loci coding for Aat-1 and Pgd-2. Independent assortment was observed for isozyme loci Idh/Pgm-2, Idh/Aat-1, Idh/Pgd-2, Pgm-2/Aat-1, Pgm-2/Pgd-2, and Aat-2/Aat-1. The red leaf locus, Gr, assorted independently of the isozyme loci: Idh, Pgm-2, Aat-1, and Pgd-2.     

Characterization of isozymes in Salvia columbariae

Summary Salvia columbariae is a herbaceous annual species which has potential for domestication as a new source of industrial oil. Isozyme markers provide a mean by which this process may be facilitated. Isozyme survey of field grown Salvia columbariae plants showed variation for malate dehydrogenase (MDH), phosphoglucose isomerase (PGI), and phosphogllucomutase (PGM). Selfed seed was obtained from the field and was grown in the greenhouse for segregation analyses. Electrophoretic results indicated that MDH was variable at zone 1, showing presence or absence of a band. The observed segregation ratio was not significantly different from expected ratio for Pgi-4 and Pgm-3 isozymes, indicating monogenic control of the two loci. Pgi-4 locus was heterozygous for a null allele. Cross dimerization between the allozyme Pgi-3 and Pgi-4 loci resulted in an intergenic band for this isozyme system.Abbreviations ACO aconitase - ADH alcohol dehydrogenase - DTT-DL dithiothreitol - FDH formate dehydrogenase - GOT glutamate-oxalacetate transaminase - IDH isocitric dehydrogenase - MDH malate dehydrogenase - MNR menadione reductase - 6PGD 6-phosphogluconate dehydrogenase - PGI phosphoglucose isomerase - PGM phosphoglucomutase - PVP-40 polyvinylpyrrolidone - SKDH shikimate dehydrogenase - TPI triosephosphate isomerase     

Segregation of isozymes in selfed progenies of a synthetic amphidiploid between Solanum integrifolium and S. melongena

Isozyme and cytogenetic analyses were performed on selfed progenies of a synthetic amphidiploid between scarlet eggplant, Solanum integrifolium (= S. aethiopicum),and eggplant, Solanum melongena `DMP', for estimating genetic uniformity. Isozymes in the 379 examined seedlings segregated into five genotypes (phenotypes) each at the four loci examined, Pgd-2 of phosphogluconate dehydrogenase (E.C.1.1.1.43), Idh-2 of isocitrate dehydrogenase (E.C.1.1.1.41), Pgm-2 of phosphoglucomutase (E.C.2.7.5.1)and Skdh-1 of shikimate dehydrogenase (E.C.1.1.1.25), indicating that the selfed seedlings were not genetically uniform. Most of the examined 15 selfed seedlings exhibited a somatic chromosome number of 48, that is the same number of the synthetic amphidiploid, whereas isozyme genotypes among them were variable. It is suggested that the segregation of isozymes was not caused by variation of chromosome number but by genetic segregation of isozyme genes. The genome of the synthetic amphidiploid was indicated to be unstable. This revised version was published online in July 2006 with corrections to the Cover Date.     

Genetic control of alcohol dehydrogenase, malate dehydrogenase, and phosphoglucomutase isozymes in lima bean (Phaseolus lunatus L.)

A suitable electrophoretic separation method for alcohol dehydrogenase (ADH). malate dehydrogenase (MDH). and phosphoglucomutase (PGM) from P. lunatus has been developed. Two loci (Adh-2 and Pgm-2) showed codominant inheritance and fitted Mendelian ratio. ADH isozyme banding patterns indicate a dimeric quaternary structure. while those of PGM were in agreement with a monomeric nature. The cytoplasmic location of two MDH isozymes (Mdh-1 and Mdh-2) selectively inactivated by homogenization in an ascorbic acid solution was demonstrated. However. distorted ratios were observed for Mdh-2 segregation. On the basis of MDH isozyme banding patterns observed in five progeny families, il is suggested that this enzyme system is a dimeric protein encoded by at least three codominant genes (Mdh-1 .Mdh-2 and Mdh-3). Joint segregation tests between pairs of segregating loci (Adh-2, Mdh-2, and Pgm-2) indicated that each of them is inherited independently.     

Genetic and linkage analysis of isozyme loci in Daucus carota L.

Summary Electrophoretic polymorphisms of eight enzyme systems were studied in leaves of Daucus carota ssp. sativus in order to identify additional isozyme loci and generate first linkage groups of genetic markers. The genetic analysis of aconitase (ACO), leucin aminopeptidase (LAP), menadione reductase (MDR), phosphoglucomutase (PGM), 6-phosphogluconic dehydrogenase (6-PGD), shikimate dehydrogenase (SKD), and triose phosphate isomerase (TPI) zymograms resulted in the identification of 8 isozyme marker loci, designated as Aco-1, Lap-1, Pgm-1, Pgm-3, 6-Pgd-2, Skd-1, Tpi-1, and Tpi-2. All loci segregated with codominant alleles and encoded for monomers (ACO, LAP, PGM, SKD), and dimers (6-PGD, TPI), respectively. MDR enzymes of the variable region MDR-2 appeared to be identical with Dia-2 isozymes. Tests of joint segregation for pairwise comparisons of all 14 isozyme marker loci now available in carrots indicate that 12 loci are linked in 4 linkage groups (marked K1 to K4) in the following order: Aco-1, Pgi-1, and Dia-3 (K1), Tpi-2, Got-2, and Lap-1 (K2), Got-3 and Tpi-1 (K3) and Pgm-1, Pgm-3, 6-Pgd-2 and Skd-1 (K4). Dia-2 and Got-1 remained unlinked. The possible duplication of a PGM locus and a 6-PGD locus is discussed.     

Chloroplast DNA diversity in eggplant (Solanum melongena) and its related species S. incanum and S. marginatum

Summary The potential of isozymes for distinguishing asparagus varieties was carried out by a survey on 21 varieties using 10 enzyme systems: GOT, SkDH, DIA, PGM, MDH, IDH, PGD, ACP, PGI, MR and ADH. Only 3 enzymes, SkDH, GOT and PGM, showed useful polymorphisms. The varieties were found heterogeneous according to their genetic structure: open pollinated varieties were more heterogeneous than clonal hybrids; the F1 hybrid and the vitroclones were homogeneous. As expected from the narrow genetic basis of the varieties, only a few alleles per isozyme locus were present. Moreover, for each enzyme, one allele or type was predominant so that the discriminating power of the method was low. However some of the varieties could be identified and different applications of the results are presented.Abbreviations D.U.S.- Distinction-Uniformity-Stability - ACO- aconitase - ACP- acid phosphatase - ADH- alcohol dehydrogenase - CAT- catalase - DIA- diaphorase - END- endopeptidase - GOT- glutamate oxaloacetate transaminase - IDH- isocitrate dehydrogenase - MDH- malate dehydrogenase - MR- menadione reductase - PGI- phosphoglucoisomerase - PGM- phosphoglucomutase - PGD- phosphoglucose dehydrogenase - POX- peroxidase - SkDH- shikimate dehydrogenase     

Expression of heritable biochemical markers from various pecan tissues

Summary Isozyme expression of malate dehydrogenase (MDH), phosphoglucomutase (PGM), and phosphoglucose isomerase (PGI) were examined from 12 tissues of pecan by starch gel electrophoresis. Tissue type, stage of development, and extraction method had little effect on isozyme expression of MDH or PGM but did influence PGI expression. Additional PGI bands were observed from seed tissue and soaked pollen. A direct relationship was observed between PGI expression from seed tissue and eventual expression from the germinated seedling. Additional PGI bands from soaked pollen were thought to be produced from structural changes and not due to more efficient extraction. The genotype of immature pecan seeds could be determined for Mdh-1, Pgi-2, and Pgm-1 provided cellular endosperm had developed. Watery endosperm did not contain detectable levels of the study enzymes. The advantages of uniform isozyme expression among various tissues and ability to determine the genotype of immature pecan seed are discussed.     

Isozyme electrophoretic characterization of 29 related cultivars of lily (Lilium spp.)

Isozyme banding patterns (IBPs) were studied for cultivars of lily (Lilium spp.) by means of horizontal starch‐gel electrophoresis (SGE). An array of continuous histidine‐citrate buffer systems at eight ranges of pH and four extraction buffers were tested. On the basis of this survey, the extraction buffer two (Eb‐2) and the buffer system E at pH 7.7 were found to be suitable for detection of lily isozymes. Using the SGE technique, IBP in catalase (CAT; EC 1.11.1.6), esterase (EST; EC 3.1.1.1), malate dehydrogenase (MDH; EC 1.1.1.37), malic enzyme (MAL; EC 1.1.1.40), peroxidase (POX; EC 1.11.1.7), phosphoglucomutase (PGM; EC 2.7.5.1), phosphoglucose isomerase (PGI; EC 5.3.1.9) and 6‐phosphogluconate dehydrogenase (PGD; EC 1.1.1.44) were assayed. In total 29 cultivars were tested in this study: nine were analysed for all eight enzyme systems, 16 cultivars for seven systems, three for six, and one for five enzyme systems. Some IBP were identified as section‐specific biochemical markers. Eight enzymes systems were analysed by constructing a dendogram using the unweighted pair group method, arithmetic average (UPGMA) cluster analysis. The analysis indicated that the lily cultivars could be separated from other Lilium species, except for two L. x formonlogi cultivars:‘Hakuba’ and ‘Hakuko’ which could not be distinguished from each other by the isozyme patterns assayed here. This study shows that isozymes can provide useful biochemical markers for lily cultivar identification and to estimate the phylogenetic relationships among those cultivars.     

Isozyme variation in Helianthus petiolaris and sunflower,H. annuus

Summary Helianthus petiolaris is a wild species used in genetic improvement of sunflower, as a donor of cytoplasmic male sterility and of genetic resistance to diseases. Isozyme variation for ADH, ACP, EST, GDH, LAP, PGI, PGD and SKDH in this species was studied using starch gel electrophoresis. The patterns thus obtained were compared with zymograms of inbred lines, hybrids and open pollinated varieties of H. annuus. The same alleles for EST and SKDH isozymes were found in both species, while ACP showed an allele that has not been found in sunflower. The rest of the isozyme systems showed both common alleles and characteristic ones for each species. ACP, GDH and PGD were monomorphic in H. petiolaris, while ADH and LAP were monomorphic in H. annuus. The isozyme markers obtained here could be useful in breeding programs involving interspecific crosses, and studies on introgression and on genetic variation in other populations of this wild species.     

Use of isozyme patterns in characterization of potato mutant lines selected for agronomic quantitative traits

Summary Seven varieties and 57 spontaneous or induced in vitro mutant lines (20 macromutant and 37 micromutant events) of potato were tested by starch gel electrophoresis for ADH, GOT, PGI, PGM, ACO, IDH, MDH and 6PGDH isozymes in tuber extracts. The data showed that in contrast to variety comparisons, the isozyme patterns rarely differentiate mutant lines which have altered morphological traits. But trying to identify isozyme differences in mutants can still be useful for a chimeric structure for GOT-2 alleles in a mutant from Atlantic and a new tuber specific locus for 6PGDH in mutants from Russet Burbank were found.Abbreviations ACO aconitase - ADH alcohol dehydrogenase - GOT glutamate oxaloacetate transaminase - IDH isocitric acid dehydrogenase - MDH malate dehydrogenase - 6PGDH 6-phosphogluconate dehydrogenase - PGI phosphoglucoisomerase - PGM phosphoglucomutase - SGE starch gel electrophoresis - EMS ethyl metanesulfonate     

Inheritance of isoenzymes and their linkage relationships in two interspecific cherry progenies

Two interspecific cherry progenies, Prunus avium 'Napoleon' × P. incisa E621 and × P. nipponica F1292, were analysed by polyacrylamide gel electrophoresis for 14 enzyme systems: aconitase (ACO), acid phosphatase (ACP), alcohol dehydrogenase (ADH), amylase (AMY), glutamate oxaloacetate transaminase (GOT), glucose–6-phosphate isomerase (GPI), isocitrate dehydrogenase (IDH), leucine aminopeptidase (LAP), malate dehydrogenase (MDH), malic enzyme (ME), phosphogluconate dehydrogenase (PGD), phosphoglucomutase (PGM), shikimate dehydrogenase (SKD) and superoxide dismutase (SOD). Thirty-one loci were deduced from segregating banding patterns, Aco–2, Acp–1 to –5, Acp–8, –9, Adh–1 to –6, Amy–2, –3, Got–1 to –3, Gpi–2, Idh–1 to –4, Lap–1, Me–1, –2, Mdh–2, Pgd–1, –2 and Sod–2. Only ten of these had previously been established. Seven putative loci were polymorphic but did not segregate in the progenies. Analysis of cosegregations and calculation of recombination fractions revealed that 15 loci could be grouped into four linkage groups: Acp–1/–2/–3–-Acp–5; Gpi–2–- Got–2–-Got–1–-Lap–1; Adh–4/–6– -Amy–2; and Adh–1–-Adh–5–-Adh–2–- Me–2. These consolidate two previously reported linkage groups and establish three new groups. The previously reported linkage of Lap–1 with Me–1 was not confirmed. Fourteen cultivars of P. avium were analysed for the same 14 enzyme systems and showed polymorphism for just 17 of the established loci and for none of the putative loci, indicating far less scope for linkage analysis in intraspecific progenies from crosses among these cultivars.     

Isozyme polymorphism in three gene pools of cultivated chicory (Cichorium intybus L.)

Summary Polymorphism of ten enzymes, acid phosphatase (APH), isocitrate dehydrogenase (IDH), leucine aminopeptidase (LAP), phosphorylase (PP), superoxide dismutase (SOD), malic enzyme (ME), glutamate oxaloacetate transaminase 1 and 2 (GOT-1, GOT-2) and phosphoglucomutase 1 and 2 (PGM-1 and PGM-2), was investigated in three gene pools of cultivated chicory, including six cultivated wild chccory, eight industrial chicory and eight Brussels chicory varieties. LAP, APH, PP and PGM-2 showed high phenotypic polymorphism whilst GOT-1 and ME had poor polymorphism. For three enzyme coding loci Lap, Pgm-1 and Got-2, allele frequencies were determined. Isozyme composition in the three chicory gene pools was significantly different, showing, respectively, high, intermediate and poor average amount of phenotypic polymorphism in cultivated wild chicory, industrial chicory and Brussels chicory. Isozyme variation within and between varieties of the three gene pools is discussed in relation to breeding practices.     

Comparison of isoenzymes in Prunus avium separated by two different electrophoretic techniques

Isoenzyme variation for seven systems revealed by two different electrophoretic procedures was compared in Prunus avium. Fourteen cultivars and 14 wild selections were analysed for acid phosphatase (ACP), isocitrate dehydrogenase (IDH), leucine aminopeptidase (LAP), malate dehydrogenase (MDH), phosphoglucomutase (PGM), shikimate dehydrogenase (SKD) and superoxide dismutase (SOD). Extracts were separated by isoelectric focusing (IEF) and by polyacrylamide gel electrophoresis (PAGE). For the eight loci that had been described previously in these enzyme systems on the basis of IEF analysis, we compared the variation revealed with IEF and PAGE. Similar variation was revealed for Acp‐1 and Pgm‐1, and the alleles revealed by PAGE could be identified directly with those reported for IEF. For Lap‐1, Mdh‐1 and Skd‐1, variation was seen with IEF but not with PAGE. For Mdh‐2, PAGE revealed additional variation not revealed by IEF. For Idh‐1, different patterns of variation were revealed by PAGE and IEF, and both procedures would be needed to genotype cherry accessions. We were unable to detect variation corresponding to that reported previously for Sod‐1 with either technique. The implications of these findings for allele labelling, for studies of genetic diversity and for linkage analysis are discussed.     

苹果酸脱氢酶在番茄F1杂种纯度检测中的应用

本文应用垂直板不连续系统的聚丙烯酰胺凝胶电泳（ＰＡＧＥ）法,分析了５个杂交一代种（佳粉一号、佳粉二号、佳粉十号、佳粉十五号、双抗二号）发芽肿种苗的五种同工酶（苹果酸脱氢酶（ＭＤＨ）、乙醇脱氢酶（ＡＤＨ）、磷酸葡萄糖变位酶（ＰＧＭ）、酯酶（ＥＳＴ）、异柠檬酸脱氢酶（ＩＤＨ）。发现５个杂交一代种中,３个要交一代种与其双亲的苹果酸脱氢酶（ＭＤＨ）谱带有有明显稳定的区别。两个杂交一代种与其双亲酯（ＥＳＴ）     

Identification of triploid Citrus by isozyme analysis

Summary Seedlessness is a desirable horticultural attribute in Citrus and is positively associated with triploidy. The conventional cytological method for triploid identification is a laborious technique involving the preparation of root tips for chromosomal analysis. Digital densitometry of isozymes, however, offers the possibility of distinguishing triploid Citrus from large populations of seedlings both quickly and cheaply. Where there are no gene dosage regulation effects, greater band density should be evident in the allozyme contributed by the diploid gamete for a heterozygous locus. The isozymes of 4 enzymes; malate dehydrogenase, 6-phosphogluconate dehydrogenase, shikimate dehydrogenase, and phosphoglucose isomerase, were investigated with polyacrylamide gel electrophoresis. Band densities of these isozymes for triploid Citrus, their diploid siblings and diploid progenitors were measured using a digital densitometer. Of the 4 enzymes investigated only allozymes for shikimate dehydrogenase exhibited consistent differences over a wide range of Citrus cultivars. Greater band density was evident in the allozyme contributed by the diploid gamete. The band density ratio between allozymes for triploid Citrus was close to 0.5, while for diploid Citrus band density ratios were close to 1.0. This effect is due to the extra protein coded by the additional gene dose and was not observed in diploids. Shikimate dehydrogenase proved to be an accurate molecular marker for distinguishing between diploid and triploid Citrus for heterozygous progeny.Abbreviations PAGE Polyacrylamide gel electrophoresis - MDH malate dehydrogenase - 6PGD 6-phosphogluconate dehydrogenase - SkDH shikimate dehydrogenase - PGI phosphoglucose isomerase     

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

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.     

Isozymes as genetic markers in bananas and plantains

Summary Twenty-four clones of banana and plantain representing various levels of ploidy and diploid M. balbisiana, were analysed for enzyme variants of malate dehydrogenase, phosphoglucomutase, glutamate oxaloacetate transaminase, shikimate dehydrogenase and peroxidase. Polymorphism was detected in all 5 enzyme systems. In addition, the four principal Cavendish clones, Robusta, Giant Cavendish, Dwarf Cavendish and Pisang masak hijau were found to be monomorphic for isozymes of 10 additional enzymes. Isozymes of glutamate oxaloacetate transminase were the most useful for discriminating among clones of a particular genomic group.Florida Agricultural Experiment Stations Journal Series No. 6858.     

Isozyme variation in cultivated and wild pineapple

Summary Isozyme variation was studied in 161 accessions of pineapple including four species of Ananas and one of Pseudananas. Six enzyme systems (ADH, GPI, PGM, SKDH, TPI, UGPP) involving seven putative loci revealed 35 electromorphs. Considerable variation exists within and between species of Ananas. Sixty-six distinct zymotypes were identified. Multivariate analyses of isozyme variation indicated that A. comosus contains five genetically diverse groups that do not match perfectly with the traditional varietal groups. Isozyme evidence also suggests that A. erectifolius is a conspecific variant of A. comosus, and that among other wild species, A. ananassoides is more closely related to A. comosus than A. bracteatus. Pseudananas is genetically distinct from all species of Ananas. It is evident from our study that differentiation among the species of Ananas may be due to ecological isolation rather than genetic divergence with breeding barriers and therefore may represent a species complex.This is journal series No. 3956 of the Hawaii Institute of Tropical Agriculture and Human Resources.     

Utilization of isozyme polymorphism for cultivar identification of 45 commercial peas (Pisum sativum L.)

Forty five Pisum sativum cultivars were analysed by isozyme electrophoresis with the objective to find protein markers for exact and reproducible discrimination of individual genotypes. The combination of six enzyme systems (acid phosphatase, amylase, esterase, leucine aminopeptidase, shikimate dehydrogenase and phosphoglucomutase) with two electrophoretic techniques (NATIVE-PAGE, isoelectric focusing) and use of seed and leaf tissue enabled to identify all 45 studied cultivars. Critical factors which may affect utilization of isozyme electrophoresis for commercial applications in pea breeding and seed production and testing are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.     

Inheritance of isozyme variants and their linkage relationships in Chinese fir (Cunninghamia lanceolata Hook.)

Summary 49 single-clone seed samples of Chinese fir (Cunninghamia lanceolata) were used to investigate genetic variation for nine enzyme systems. LAP, PGM, and SOD were invariant, whereas GDH, GOT, IDH, MDH, 6PDH, and SKDH were highly variable. Inheritance patterns of the variable enzyme systems were mostly in accordance with Mendelian expectations. Linkage was studied by analysing 43 two-locus combinations with the following two-locus combinations significantly linked in at least 50% of the respective double-heterozygous clones: Gdh1: Got3; Gdh1: Idh1; Got2: 6Pdh2; Idh2: Skdh1; Mdh1: 6Pdh1. Estimates of recombination frequencies for each locus pair varied considerably among clones.Supported by the Carl Duisberg Gesellschaft.