Esterase Isozyme Patterns Research Articles

Electrophoretic banding patterns of esterase isozymes in fresh water fish Channa punctatus

Electrophoretic banding patterns of esterase isozymes in fresh water fish Channa punctatus

Biochemical studies on electrophoretic banding pattern among the different isolates of Colletotrichum capsici causing fruit rot in chilli

Ten isolates of Colletotrichum capsici collected from different regions of Vidarbha and Marathwada (Maharashtra), Bidar district (Karnataka) and Guntur district (Andra Pradesh) showing varied type of pathogenic ability against chilli variety Jayanti and designated as strongly, moderately and weakly pathogenic on the basis of per cent leaf area covered by the disease. Electrophoresis pattern of polyphenol oxidase, esterase and protein have been used to estimate the polymorphism in different fungal populations or species. Therefore, studies were undertaken to know the biochemical variation among the isolates of C. capsici in the form of appearance of isozyme and protein banding pattern on polyacrylamide gel. Electrophoretic protein banding pattern revealed that, Rm values ranged between 0.208 to 0.725 possessing 1 to 4 bands. Isolates among weakly to highly pathogenic, 5 isolates exhibited one band each, while two bands each were existed in 3 isolates. Three bands of Cc6 (Rm value 0.208, 0.350 and 0.725) relates to strongly pathogenic. Polyphenol oxidase isozyme was estimated and Rm values were observed from 0.057 to 0.192, possessing 2 to 3 bands. Eight isolates showed presence of 3 bands each whereas, 2 isolates exhibited 2 bands with Rm values 0.142 and 0.192. Esterase isozyme pattern was observed in all the test isolates of C. capsici and Rm values ranged from 0.048 to 0.544 possessing 3 to 4 bands.

Self-Incompatibility inMatricaria chamomillaL. (Asteraceae) Is Linked to Differential Esterase Activity

Premise of research. Self-incompatibility (SI) is a frequent mechanism of plants to avoid self-pollination. Pollen esterases (EC 3.1.1.−) play an important role in pollination by enabling the penetration of pollen tubes through the cutin layer (cutinases). Therefore, their composition could contribute to SI. To test this hypothesis, esterase activity and isozyme profiles between self-compatible and self-incompatible chamomile plants (Matricaria chamomilla L., Asteraceae) were compared.Methodology. Stable self-incompatible plants were selected, and the approximate number of alleles contributing to SI were determined in a full-diallel cross. Esterase activity of self-compatible and self-incompatible chamomile plants was tested on the four substrates that follow: 1-naphthyl acetate, 2-naphthyl acetate, 1-formyl-2-naphthyl acetate, and indoxyl acetate. Esterases were characterized by electrophoretic methods, both concerning protein size and isozyme pattern in two different buffer systems.Pivotal results. Seventeen percent of all plants analyzed were self-incompatible. Eight self-incompatible plants—crossed in a full diallel—showed six different alleles responsible for SI, a number that can only be regarded as a minimum number of alleles due to the low sample size. Self-incompatible plants showed a significantly lower esterase activity for the two substrates, namely, 1-naphthyl acetate and 2-naphthyl acetate. With 1-formyl-2-naphthylacetate, however, esterase activity of self-incompatible plants was higher than that of self-compatible plants. With indoxyl acetate, no significant difference between self-incompatible and self-compatible plants could be found. The different esterase isozyme patterns observed did not correlate to the compatibility mechanism.Conclusions. The composition of pollen esterases is variable and could contribute to SI by differences in their substrate specificity.

Use of Electrophoretic Patterns of Proteins and Isozymes to Characterize Trichoderma Isolates from Cotton Roots

Proteins of 15 isolates of T. longbrachiatum and T. harzianum were compared by polyacrylamid gel electrophoresis (PAGE) and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Gels were stained with silver nitrate. Protein banding patterns of the isolates were subjected to cluster analysis by the unweighted pair-group method based on arithmetic mean (UPGMA). Apart from T. harzianum isolates T6 in PAGE and T27 in SDS-PAGE, which occupied separate positions in the phenograms, it was possible to delineate the isolates of each species on the basis of the results of PAGE and SDS-PAGE. Peroxidase (EC 1.11.1.7) and esterase (EC 3.1.1.1) isozymes from mycelium and conidia of Trichoderma isolates were separated by PAGE, and the obtained banding patterns were visualized by using specific staining systems. Cluster analysis indicated that delineation of the isolates of each species was not possible on the basis of the electrophoretic patterns of peroxidase. On the contrary, patterns of esterase isozymes provided a reliable method for grouping the isolates of each species with the exception of T9 and T14 of T. longbrachiatum, which occupied separate positions in the phenogram.

Reported populations of Meloidogyne ethiopica in Europe identified as Meloidogyne luci.

The tropical group of root-knot nematodes (RKN) including Meloidogyne ethiopica and M. luci is a highly polyphagus and damaging group of agricultural pests. M. ethiopica has been detected in several European countries (Slovenia, Italy, Greece) and also in Turkey. However, a description of a new sister species M. luci calls for reclassification of all European and Turkish M. ethiopica populations reported up to date as M. luci. Accurate identification can be accomplished through analysis of the esterase isozyme pattern, which is the most distinguishing character between the two otherwise very similar species. Both species display a three banded esterase pattern where the upper band is slightly shifted between the two species. In addition, molecular characterization of M. ethiopica and M. luci populations revealed that the ITS, SSU, and LSU of the rDNA regions are not appropriate markers for studying relationships among the tropical group of RKNs. However, the COII/lRNA region on mtDNA proved to be very useful for analyzing the phylogenetic relationship of these very closely related species/populations. Mitochondrial sequences with low levels of heteroplasmy allowed clustering of all M. luci populations in a monophyletic clade with a clear separation of this recently described species from M. ethiopica. At the same time, a very close relationship between M. ethiopica and M. luci was confirmed again.

Identification of Morphological Character and Esterase Isozyme Pattern in Second-Generation Black Rice Plant Irradiated to Gamma Rays

Black rice is one of the functional foods due to its high anthocyanin content. Black rice grain was irradiated by gamma rays with a dose of 200 Gy and 300 Gy. The main purpose of this irradiation is to induce mutation to the black rice plant in order to achieve the improved organism. This study was undertaken to elucidate the morphological character and esterase isozyme pattern of black rice plant after irradiated by gamma rays. There were morphological differences on leaves, stems and grains between irradiated and non irradiated black rice plant. Gamma radiation dose of 200 Gy showed the significant influence of the length of the stem, number of internodes, and length of leaves. The radiation dose of 300 Gy showed the significant influence of the decrease value of diameter of 3rd internodes, number of branches and width of leaves. Flowering time is getting faster as increasing radiation dose. At the age of 74 days after planting there are 9.15% plants of 200 Gy radiation dose that have flowered faster than normal plants. This value increased into 11.45% at the dose of radiation 300 Gy. There were differences in the esterase banding pattern between radiation dose of 200 Gy and 300 Gy than the control plants, indicated that randomly mutation has occurred.

三棱角油菜两类角果的酯酶同工酶和过氧化物酶同工酶比较分析

本文以3个甘蓝型三棱角油菜为材料，在油菜花角期对各材料长度分别为1 cm、3 cm以及5 cm三个不同发育阶段的幼嫩三棱角果(三室)和普通角果(两室)的酯酶(EST)和过氧化物酶(POD)同工酶进行聚丙烯酰胺垂直板凝胶电泳和酶谱的比较分析，以研究三室角果与两室角果在EST和POD同工酶水平上的异同性。研究结果表明：1) 同一材料相同发育阶段三室角果和两室角果的EST同工酶，其带型表现一致，无明显差异，但个别同工酶的酶活性有一定的差异；同一材料相同发育阶段两者的POD同工酶，其带型也表现一致，只是少数同工酶的酶活性有一定的差异。2) 同一材料在三个不同发育阶段的三室角果或两室角果的EST同工酶带型无明显差异，POD同工酶带型也无明显差异，但酶活性存在一定的差异。3) 对EST同工酶和POD同工酶而言，角果越小，酶活性越强，即随着角果的生长发育其酶活性表现为减弱的趋势。4) 3个材料的EST同工酶酶谱比较而言，14ds67与14ds72的酶谱相似程度较高，带型一致，而14ds78的酶谱与前两者的差异较大，说明三棱角材料14ds67和14ds72的亲缘关系较近，而14ds78与前两者的亲缘关系较远。然而，3个材料的POD同工酶酶谱相比较无明显差异，酶带的一致性较好，只是少数条带的酶活性有一定的差异。5) POD同工酶酶谱的酶带数目明显少于相应材料的EST同工酶酶谱的酶带数目，而且迁移快的条带为强带。因此，三室角果与两室角果分别在EST同工酶酶谱和POD同工酶酶谱水平上表现出较强的一致性。 To study the differences of Esterase (EST) and Peroxidase (POD) isozymeograms between triquetrum-siliques (tri-loculus) and ordinary siliques (bi-loculus) of triquetrum-silique materials in Bras- sica napus L., the enzyme spectrums of young siliques of length of 1 cm, 3 cm and 5 cm from 3 selfing populations were analyzed by the polyacrylamide vertical board gel electrophoresis in flowering and silique stage of rapeseed. The results show that: 1) There were no obvious differences in EST isozyme patterns between tri-loculus siliques and bi-loculus siliques in the same developmental stages for the same materials, but there were certain differences in enzyme activity for individual isozymes. In POD isozyme patterns, tri-loculus siliques and bi-loculus siliques were also similar, but there were certain differences in enzyme activity for a few isozymes. 2) The patterns of EST isozymeograms had no significant difference to the siliques in 3 developmental stages for the same materials, the patterns of POD isozymeograms had also no significant difference, but there were some differences in enzyme activity for them. 3) On EST and POD isozymeograms, the smaller the siliques were, the stronger the enzyme activity would be, i.e., the enzyme activity showed a decreasing trend along with the growing and developing of the siliques. 4) Isozyme spectrums of EST isozymeograms of 3 materials in contrast, 14ds67 and 14ds72 had high similarity, and the patterns were consistent, but 14ds78 had greatly difference with the former two. So 14ds67 and 14ds72 had close genetic relationship, and 14ds78 was far away in genetic relationship with the former two. However, isozyme spectrums of POD isozymeograms of 3 materials had no obvious difference, and the enzyme patterns with good consistency, just a few enzyme patterns had certain differences in enzyme activity. 5) The number of bands of POD isozymeograms was significantly less than that of EST isozymeograms for the same materials, and the bands moved fastest were highest in enzyme activity in the enzyme spectrums of POD isozymeograms. Therefore, there are strong consistency in EST isozyme zymogram and POD isoenzyme zymogram, respectively, between tri-loculus siliques and bi-loculus siliques in the same developmental stages for the same materials.

Mitochondrial coding genome analysis of tropical root-knot nematodes (Meloidogyne) supports haplotype based diagnostics and reveals evidence of recent reticulate evolution.

The polyphagous parthenogenetic root-knot nematodes of the genus Meloidogyne are considered to be the most significant nematode pest in sub-tropical and tropical agriculture. Despite the crucial need for correct diagnosis, identification of these pathogens remains problematic. The traditionally used diagnostic strategies, including morphometrics, host-range tests, biochemical and molecular techniques, now appear to be unreliable due to the recently-suggested hybrid origin of root-knot nematodes. In order to determine a suitable barcode region for these pathogens nine quickly-evolving mitochondrial coding genes were screened. Resulting haplotype networks revealed closely related lineages indicating a recent speciation, an anthropogenic-aided distribution through agricultural practices, and evidence for reticulate evolution within M. arenaria. Nonetheless, nucleotide polymorphisms harbor enough variation to distinguish these closely-related lineages. Furthermore, completeness of lineage sorting was verified by screening 80 populations from widespread geographical origins and variable hosts. Importantly, our results indicate that mitochondrial haplotypes are strongly linked and consistent with traditional esterase isozyme patterns, suggesting that different parthenogenetic lineages can be reliably identified using mitochondrial haplotypes. The study indicates that the barcode region Nad5 can reliably identify the major lineages of tropical root-knot nematodes.

Screening Studies on Isozyme Pattern in all leaves ofDuraVariety of Oil Palm (Elaeis guineensis Jacq.) for Selection of Leaf Index

Patterns of soluble proteins, peroxidase and esterase isozymes were identified in 32 leaves (unopened-leaf to leaf no. 31) of dura variety of palm. In addition, peroxidase enzyme activity of all the 32 leaves was carried out. The results indicated that patterns of soluble proteins, peroxidase, esterase isozymes and also the peroxidase enzyme activity were varying from leaf to leaf. The present study suggested that the 9th leaf can be sampled for analyzing soluble protein patterns due to development of high intensity bands. However, younger leaves (from 9th to 24th) for peroxidase and immature leafs i.e., unopened or 1st leaf can be used for esterase isozyme study. Thus, identification of index/candidate leaf is of utmost importance, it helps to screen tolerance of oil palm trees for large scale plantations.

ESTERASE ISOZYME PATTERNS DURING DEVELOPMENT OF BACTROCERA PAPAYA

One of the major horticultural crop pests is the Asian papaya fruit fly, Bactrocera papaya Drew & Hancock (Diptera: Tephritidae), in the tropical and subtropical regions of the world, which causes severe damage to the fleshy fruits and vegetables. Polyacrylamide gels were used for the first time to study the esterase isozyme patterns during different life stages and also to observe the enzyme patterns in the progeny (F1 generation) of B. papaya, which were maintained generation by generation under the laboratory condition. Four esterase isozymes, EST-1, EST-2, EST-3 and EST-4, were detected and their relative mobility values were 0.40, 0.26, 0.20 and 0.15, respectively. There was EST-1(0.40) with high mobility and EST-4(0.15) showed lowest mobility, closed to the cathode. These esterase isozymes were designated from the anodal end of the gel, i.e., the highest to lowest relative mobility. EST-1(0.40), EST-20.26 and EST-3(0.20) bands were only present in larval stage. EST-4(0.15) band was observed in all developmental stages except eggs. The thickness and the staining degree of bands varied in different developmental stages. In larvae, EST-1(0.40) band was very thin, EST-2(0.26) band was very thick and highly stained and EST-3(0.20) band was thin. The band of EST-4(0.15) was thick in larval and pupal stages, and comparatively very thick and highly stained in adults of both males and females. These variations of esterase isozymes indicated that it had stage-specific patterns in this pest species. In the progeny (F1 generation) of B. papaya, especially larvae and adults showed the similar esterase isozyme band patterns, comparing with their parents. The findings of the present research could be used for distinguishing this pest from other Bactrocera species as well as helpful to develop an environment friendly control method for this pest.

Electrophoretic Patterns of Esterases in Eri silkworm Samia Cynthia ricini

The present study was carried out to investigate the patterns of esterase isozymes extracted from the silk gland, haemolymph and mid gut of Eri silkworm (Samia Cynthia ricini). The qualitative analysis of esterases was carried out by 7.5% of native Polyacrylamide Gel Electrophoresis (PAGE). The inhibitor sensitivity of the enzymes towards paraxon, eserine and pCMB was used to classify the individual zones of esterases. Three zones of esterases were observed in different tissues of Eri silkworm. Silk gland esterases were classified as CHsp (Cholinesterase like enzymes) esterases. The haemolymph and mid gut esterases were classified into Esdp (Enzyme inhibited by paraxon and pCMB).

A new cell line (NTU-SE) from pupal tissues of the beet armyworm, Spodoptera exigua (Lepidoptera: Noctuidae), is highly susceptible to S. exigua multiple nucleopolyhedrovirus (SeMNPV) and Autographa californica MNPV (AcMNPV)

A new continuous cell line, NTU-SE, was established from the pupal tissues of an economically important pest, the beet armyworm Spodoptera exigua (Lepidoptera: Noctuidae). This cell line contains four major morphologic types: round, polymorphic, spindle-shaped, and comma-shaped cells. The population doubling time of this new line in TNM-FH medium supplemented with 8% fetal bovine serum (FBS) at 28°C is 35.5h. The chromosomal spread from NTU-SE cells is typical to the chromosomal morphology of lepidopteran cell lines. Confidently, NTU-SE cell line is a new cell line that exhibits distinct isozyme patterns of esterase, lactate dehydrogenase (LDH), and malate dehydrogenase (MDH) from those of the other insect cell lines. In addition, the DNA sequence of the nuclear ribosomal internal transcribed spacer (ITS) region of NTU-SE cells is above 96% identical to that sequence of S. exigua larvae, as compared to only 66% identical to that of S. litura larvae. The NTU-SE cell line is highly susceptible to S. exigua multiple nucleopolyhedrovirus (SeMNPV) and Autographa californica MNPV (AcMNPV). Therefore, a highly virulent SeMNPV strain, SeMNPV-1, had been successfully isolated and propagated in NTU-SE cells. We conclude that the NTU-SE cell line will be a useful tool for the selection and mass production of highly virulent SeMNPV strains for the S. exigua biocontrol and the baculovirus based recombinant protein expression systems.

고도에 따른 지역별 복숭아혹진딧물 집단 변이 마커 개발

This study focused on the green peach aphid, Myzus persicae, as an indicator pest in Chinese cabbage cultivation to develop a genetic marker. We hypothesized that M. persicae gene flow is related to climate change. Genetic variation was analyzed using five local populations collected at different altitudes (157 m, 296 m, 560 m, 756 m and 932 m above sea level) in Hoengseong, Pyeongchang, and Gangneung areas, plus a laboratory strain used as an outgroup. There were no differences in ecological characteristics among strains. Esterase isozyme pattern and inter-simple sequence repeat (ISSR) PCR results showed significantly different bands between laboratory and wild, local populations. However, there was no difference among local populations. Partial fragments of ribosomal RNA (rRNA) and mitochondrial cytochrome oxidase I (mtCO I) were amplified and their nucleotide sequence was analyzed. Single nucleotide polymorphisms (SNPs) were detected in internal transcribed spacer-2 (ITS-2) and mtCO I regions among the five local populations. These SNPs can be use to discriminate different populations of M. persicae to monitor gene flow.

Transfer of transformed Lesquerella fendleri (Gray) Wats. chloroplasts into Orychophragmus violaceus (L.) O.E. Schulz by protoplast fusion

Asymmetric intergeneric hybrid plants were obtained through protoplast fusion between Orychophragmus violaceus (L.) O.E. Schulz and Lesquerella fendleri (Gray) Wats. The latter carried chloroplasts transformed with the fused aadA16gfp gene construct, conferring streptomycin–spectinomycin resistance and UV-induced green fluorescence. The somatic hybrids were selected using the properties of spectinomycin-induced plastid defects in “albino” O. violaceus plants (chloroplast recipient) combined with the γ-irradiation-induced inactivation of nuclei in plastid donor L. fendleri. The morphology and esterase isozyme pattern of the hybrid plant as well as the results of the PCR analysis of internal transcribed spacer of nuclear ribosomal DNA proved that the regenerated hybrids carried O. violaceus nuclei, while PCR amplification of the atpB–rbcL spacer and aadA16gfp gene fragments confirmed the presence of the transformed L. fendleri chloroplasts in these plants. Expression of the fused aadA16gfp gene construct was confirmed by sodium dodecylsulfate–polyacrylamide gel electrophoresis analysis and the resistance of the obtained plants to both streptomycin and spectinomycin.

Pyrethroid synergists suppress esterase-mediated resistance in Indian strains of the cotton bollworm, Helicoverpa armigera (Hübner)

The role of esterase in pyrethroid resistance was studied in the final larval instar of different strains of the cotton bollworm, Helicoverpa armigera. The resistant strains viz., Nagpur strain and the Delhi strain were found to have elevated midgut esterase activity in comparison to the susceptible strain. Nagpur strain and Delhi strain have 2.24 and 1.73-fold higher esterase activity, respectively, than that of the susceptible strain. The Native PAGE displayed important differences in the midgut esterase isozyme pattern between the susceptible and the pyrethroid-resistant strains. Out of the 10 esterase isozyme observed, susceptible strain lacked three bands, E2, E6 and E10 that were found in the resistant strains. The potency of the synergists piperonyl butoxide (PBO) and dihydrodillapiole (DDA) as esterase inhibitor were also studied both in vitro and in vivo. The in vitro results clearly show that both PBO and DDA inhibited esterase activity in the two resistant strains, while there was almost no esterase inhibition in the homogenate of the susceptible strain. The in vivo inhibition studies (topical application of PBO and DDA followed by biochemical analysis) illustrated that PBO- and DDA-esterase binding is rather slow and non permanent process. Esterase inhibition did not occur immediately after the synergist treatment but at 4 and 8 h post treatment in case of PBO and DDA, respectively. Native PAGE revealed that the in vivo esterase inhibition caused by both PBO and DDA was due to the binding of the synergist with the E6 isozyme which was not present in the susceptible strain.

Effect of environmental and genetic factors on the stability of pea (Pisum sativum L.) isozyme and DNA markers

Environmental (geographic location, year-to-year effect) and genetic (intravarietal variation) effects on the stability of the isozyme patterns of esterase (EST), acid phosphatase (ACP), alcohol dehydrogenase (ADH), leucine aminopeptidase (LAP), shikimate dehydrogenase (SDH) and glucose-6-phosphate isomerase (PGI) used for pea cultivar genotyping were studied. In addition, selected DNA markers (RAPD, SSR, ISSR, IRAP) were used to study intravarietal genetic homogeneity/variation at a DNA level. Five commercial dry-seed pea (Pisum sativum L.) cultivars Canis, Gotik, Komet, Sonet and Zekon were grown during four years (2001 – 2004) in three locations in the Czech Republic (Šumperk, Čáslav, Uherský Ostroh) that differed in soil and climatic characteristics. Mature dry seeds were used as a standard input sample for analyses. No variation in isozyme spectra was found within particular cultivars between years, locations and fruiting nodes in enzymes providing in general a low polymorphism in pea cultivars (ACP, ADH, LAP, SDH, PGI); similarly, these enzymes also exhibited high stability as related to intravarietal variation. In contrast, EST – highly polymorphic in pea cultivars – showed certain qualitative variation within particular cultivars as related to both environmental and genetic factors. The intravarietal variation detected by selected DNA markers was negligible and mostly quantitative. Possible reasons for the instability/variation of isozyme markers are discussed from the aspect of cultivar genotyping used in pea breeding and seed production.

First record of the Q biotype of the sweetpotato whitefly, Bemisia tabaci, in Guatemala

Bemisia tabaci (Gennadius) adults and immatures were collected from poinsettia plants at two commercial production greenhouses in Guatemala during an invited tour to observe IPM practices within the facilities. Despite extensive scouting, only low numbers of insects were collected from vegetable, weed and wild ornamentals species located close to these facilities. Prior to molecular and biochemical analyses, whitefly immatures were initially identified as B. tabaci using morphological characters of the pupae to distinguish them from the greenhouse whitefly. The biotype status of adults and immatures was then established using esterase isozyme patterns and MTCO1 sequencing. The Q biotype was the only biotype found on commercially grown poinsettia plants. The previously recorded B biotype was observed outside the greenhouse facilities on Lactuca spp., Hibiscus spp. and Euphorbia spp. (wild poinsettia). The New World biotype was observed on wild poinsettia and field-grown beans (Phaseolus spp.). This is the first report of the Q biotype in Guatemala, and serves notice of the need for greater vigilance in the management of whiteflies on poinsettia mother stock used as a source of cuttings for export to the USA.

Efeito de diferentes componentes no meio de cultura na produção de alcalóides em tecidos de calos de Cereus peruvianus (Cactaceae)

The production of alkaloids from Cereus peruvianus callus cultured in medium supplemented with different tyrosine concentrations, different 2,4-D/kinetin levels, and with NaCl was investigated using long-term callus culture. α- and β-Esterase isozyme patterns were also analyzed to investigate the differential gene expression in callus subcultured with the different tyrosine concentrations. The greatest amounts of alkaloids were obtained from callus maintained in medium containing 200 mg/L of tyrosine. Tyrosine induced a differential gene expression for the synthesis of specific α- and β -esterase isozymes. Two α-carboxylesterases (EC 3.1.1.1) and one α/β-arylesterase (EC 3.1.1.2) were induced in callus, one α/β-acetylesterase (EC 3.1.1.6) and two α-carboxylesterase were detected as more intensely stained while two α/β-carboxylesterases were absent or detected as more weakly stained bands after the addition of tyrosine as precursor

First Report of the Root-Knot Nematode Meloidogyne ethiopica on Tomato in Slovenia.

The root-knot nematode Meloidogyne ethiopica Whitehead originally described from Tanzania is also distributed in South Africa, Zimbabwe, and Ethiopia (3). Although this species is a relatively unknown root-knot nematode, M. ethiopica parasitizes several economical important crops, such as tomato, cowpea, bean, cabbage, pepper, pumpkin, tobacco, lettuce, and soybean (4). This species can be morphologically confused with M. incognita (Kofoid & White), and therefore, is probably easily overlooked (1). Recently, characteristic esterase isozyme patterns were described for this species, which provide a more reliable identification (2). In October 2003, Lycopersicum esculentum cv. Belle plants with large root-galls were observed in a greenhouse at Dornberk, Slovenia, which were identified as an unknown root-knot nematode within the M. incognita group. Subsequent sampling revealed infestation of all tomato plants within this greenhouse with obvious aboveground symptoms of stunting and wilting. Additional morphological and isozyme studies identified this root-knot nematode as M. ethiopica. The identification was based on female, male, and second-stage juvenile morphology and malate dehydrogenase and esterase isozyme phenotypes from young egg-laying females isolated from 20 tomato plants and compared with a culture of M. ethiopica from Africa. To our knowledge, this is not only the first report of M. ethiopica in Slovenia, but also the first report of this species in Europe.

Recent developments in biochemical characterization of Vitis vinifera L. varieties in Hungary

Isoelectric focusing is an effective and well reproducible method to provide information for identification of various plant species and clones if breeding or other genetic modification(s) for a given species are reflected in changes of an isozyme pattern. The method has been used for characterization of plant proteins and enzymes and for identification of various species and varieties. Our aim was to continue our several-year-work carried out on a wide variety of grapevine varieties and to reveal whether analyses of esterase and peroxidase isozyme patterns are suitable to distinguish various grapevine varieties. Therefore we compared esterase and peroxidase isozyme patterns of various species. Plant samples were obtained from Szigetcsep, Kecskemet, Tokaj and Eger. The following samples were analyzed: Pinot gris, noir, blanc, Chardonnay, Riesling Theses, Chasselas from Szigetcs6p, Bianca and his parents Eger2 and Bouvier from Kecskemet, Furmint and Hárslevelű from Tokaj, Kékfrankos and Zweigelt from Eger. To identify various species according to their esterase isozyme patterns the after blooming phenological phase while according to their peroxidase isozyme pattern the dormant phenological phase was found as optimal sampling time.