Characterisation of benzimidazole resistance of Cercospora beticola in Serbia using PCR-based detection of resistance-associated mutations of the β-tubulin gene

A survey to detect and characterise benzimidazole resistance within populations of Cercospora beticola in Serbia was performed. From 52 field isolates collected from sugar beet and beet root, only eight were found to be benzimidazole-sensitive based on the inhibition of mycelial growth by discriminatory concentrations of carbendazim and thiophanate-methyl. Sensitivity tests revealed the presence of three resistant phenotypes among the tested isolates: high-resistance (HR), low-resistance (LR) and moderate-resistance (MR). The benzimidazole resistant isolates were characterised based on the DNA sequence of the β-tubulin gene and temperature sensitivity. The HR isolates showed no temperature sensitivity regardless of carbendazim concentration, whereas the LR and MR isolates were sensitive at lower temperatures. Analysis of the β-tubulin gene sequence revealed two amino acid replacements in the benzimidazole-resistant isolates of C. beticola. One was a glutamic acid to alanine change at position 198 (codon GAG to GCG) that was identified in HR isolates; this mutation has previously been reported to be associated with the development of benzimidazole resistance in C. beticola. The second replacement was a novel point mutation of phenylalanine (TTC) to tyrosine (TAC) at position 167, identified in low and moderate benzimidazole-resistant isolates, sharing a single LR/MR β-tubulin genotype. A diagnostic PCR-RFLP assay utilising a BsaI restriction site present in the benzimidazole sensitive and LR/MR genotypes but absent in the HR genotype was developed for the routine detection of high resistance. A mutation-specific PCR assay was developed for the diagnosis of LR/MR genotype based on a mutation from T to A at codon 167, which is unique to this genotype.     

Study of precursors responsible for off-flavor formation during storage of potato flakes

Off-flavors frequently appear during the storage of potato flakes. Volatile profile analysis performed by solid-phase microextraction-gas chromatography-mass spectrometry revealed that hexanal is the main compound that appears during the storage period. Hexanal may be a degradation product of linoleic acid formed through linoleic acid hydroperoxide cleavage. Profiles of hexanal precursors were determined from potato flakes at different storage time points. Linoleic acid-derived oxylipins are predominant in potato flakes. The free oxylipins identified, in descending order, are as follows: hexanal, hydroxy polyunsaturated fatty (PUFAs), oxo PUFAs, divinyl ether PUFAs, and hydroperoxy PUFAs. However, the main oxylipins detected were esterified: esterified hydroxy, hydroperoxy, and oxo PUFAs. Oxylipins reveal different evolutions during the storage period. Chiral high-performance liquid chromatography analysis of the precursors of hexanal and other oxylipins revealed a racemic composition that supports the nonenzymatic formation of hexanal and most of the other oxylipins identified.     

Detection of Anaplasma dna in Ixodes ricinus ticks: pitfalls

A total of 150 nymphal Ixodes ricinus (L., 1758) (Acari: Ixodidae) from the Czech Republic were examined for Anaplasma phagocytophilum (Foggie, 1949) Dumler et al., 2001 by PCR using EHR521/747 primers: 22 of 50 pools were positive (minimum prevalence, 14.7%). However, sequencing of the PCR products did not show complete homology with A. phagocytophilum (91%) while the closest relationship (95%) was found to "Candidatus Ehrlichia walkefii". The results indicate a need for care in interpretation of Anaplasma PCR results and for PCR optimization for detecting A. phagocytophilum in ticks.     

An efficient protocol for genomic DNA extraction from formalin-fixed paraffin-embedded tissues

Formalin-fixed paraffin-embedded tissues (FFPET) represent the largest source of archival biological material available for genomic studies. In this work we present an advanced protocol for extraction of high quality DNA from FFPET that can be applied in several molecular studies. Although cat mammary tumours (CMT) are the third most frequent tumour in cats the recovery of significant number of samples for molecular studies are in some way restricted to FFPET samples. We were able to obtain high quality DNA from FFPET of thirty six CMT that were subjected to pre-fixation and fixation processes routinely used in the veterinary hospitals. The quality of DNA obtained was tested by PCR amplification using six sets of primers that amplify single-copy fragments. The DNA fragments obtained were further sequenced. This protocol was able to provide FFPET gDNA that can be amplified and sequenced for larger fragments up to 1182bp.     

Use of land-races in Czechoslovak wheat breeding

Summary Four groups of Czechoslovak land-races (Czech alternate, Czech red, Moravian white, awnless, South Moravian and Slovak awned wheats) are characterized on the base of wheat collection studies in the Research Institute for Crop Production, Praha-Ruzyn, and their use in the breeding in SSR. A review of Czechoslovak cultivars of winter and spring wheats registered in the years 1921–1980 (table 1 and 2) and the registration period of the most important older Czechoslovak cultivars (table 3) is presented.Of the total number of 284 registered Czechoslovak cultivars in the years 1921–1980 93 cultivars were developed by selection from land-races; 70% of 87 cultivars originated from crosses had a land-race or its derivative as one of its parents. From land-races derived cultivars Chlumecká 12, eská Pesívka, Slovenská 777, Dobrovická 10 displayed the longest duration in the registration.

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Die Verwendung von Landsorten in der tschechoslowakischen Weizenzüchtung

Zusammenfassung Vier Gruppen von tschechoslowakischen Weizenlandsorten werden auf der Grundlage von Untersuchungen an der Weizenkollektion im Institut für Pflanzenproduktion, Prag-Ruzyn, und ihrer Nutzung in der Züchtung in der SSR beschrieben. Es sind (1) tschechische Wechselweizen, (2) tschechische rote, (3) mährische weiße, grannenlose und (4) südmährische und slowakische begrannte Weizen. Ein Überblick über die in den Jahren 1921–1980 registrierten tschechoslowakischen Winter- und Sommerweizen (Tab. 1 und 2) sowie die Zeitdauer der Registrierung der bedeutendsten älteren tschechoslowakischen Sorten (Tab. 3) schließt sich an.Von insgesamt 284 in den Jahren 1921–1980 registrierten tschechoslowakischen Sorten entstanden 93 durch Auslese aus Landsorten. Bei den 87 Sorten, die aus Kreuzungen hervorgingen, hatten 70% entweder eine Landsorte oder den Abkommen einer Landsorte unter den Eltern. Die aus Landsorten hervorgegangenen Sorten Chlumecká 12, eská Pesívka, Slovenská 777 und Dobrovická 10 waren am längsten registriert.

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- : (1) , (2) , (3) , (4) . , 1921–1980 . (. 1 2), ( ) (. 3). 284 , 1921–1980 ., 93 ë . 87- , ë , 70% . ( ) : 12, , 777 10.

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Paper not delivered during the symposium     

Effect of drying conditions and storage period on polyphenolic content, antioxidant capacity, and ascorbic acid of prunes

In this study the main chemical parameters, ascorbic acid and polyphenol content, and antioxidant activity of two varieties of prunes, dried by high-temperature (85 + 70 degrees C) and low-temperature (60 degrees C) procedures, were monitored during storage. Ascorbic acid content was higher in the prunes dried at 60 degrees C but significantly decreased in both varieties during storage. The different classes of polyphenols analyzed (cinnamates, anthocyanins, flavonols) showed different stabilities during storage. Neochlorogenic acid decreased only in the President variety, whereas chlorogenic acid increased in both varieties; anthocyanins, present only in the President prunes, disappeared in the first months of storage, and the flavonol content fell significantly in both cultivars during the year of the study. Drying temperature significantly affected the polyphenol content, with different effects according to the class of polyphenols. Antioxidant activity showed a significant increase at the end of the storage period and in the President variety was higher in the sample dried at the higher temperature.     

Sugar yield,nitrogen uptake by sugar beet and optimal nitrogen fertilization in relation to nitrogen soil analyses and several additional factors

To test the relative usefulness of different methods of chemical analysis for soil nitrogen fractions in the assessment of the fertilizer nitrogen needs of sugar beet, different doses of nitrogen were applied in field experiments laid out during the years 1985–1991. The chemical methods used were N mineral (NO _– ³ +NH ₊ ⁴ ) analyses on soil samples taken in late winter, and extraction with 0.01 M CaCl₂ from soil samples taken the preceding autumn and in late winter. The results of the chemical methods were evaluated in models using estimated optimum nitrogen fertilization, nitrogen present in beets or beets+leaves at leaf maximum and sugar yield as variables. In addition, parameters such as estimates of possible rooting depth and mineralization capacity of the soil were also included in the model. All models for estimating nitrogen fertilization need showed low R ² values. The two methods of soil chemical analysis yielded similar R ² values for nitrogen uptake in plots both with and without nitrogen fertilization. The N mineral method was least useful in predicting sugar yield. Addition of the covariables rooting depth and mineralization capacity appreciably improved the explanatory value of the models with 0.01 M CaCl₂, especially when the analytical results of soil samples taken in autumn were used. For the N mineral method the addition of covariates was found to have far less influence.     

Factors contributing to the development of aluminum resistance in the Madeiran maize germplasm

Forty genotypes representing maize genetic diversity from the Island of Madeira were screened for resistance to aluminum (Al) in nutrient solution. Seeds of maize were obtained from local farmers from field plots spread around the island in a range of altitudes from 99 to 1000 m above sea level. The content of ionic aluminum and the pH of soils cultivated with maize were determined. The mean pH value of all examined soils was 4.9, while the mean ionic Al content was 0.76 cmol kg^–1. Seventy‐two hours (h) exposure to 100 and 200 μM Al followed by a 48 h recovery period of 4‐day old seedlings revealed significant differences in Al resistance in the Madeiran maize germplasm. Root survival and regrowth exceeding 80 % of the seedlings were observed in 22 and 8 of the tested genotypes screened at 100 and 200 μM Al in nutrient solution. High Al resistance among Madeiran maize genotypes appeared not to be associated with the lower pH of soil, and did not correlate with the amount of soil Al³⁺ or the altitude at the site of collection. The high level of Al resistance of the maize cultivars indicates an initial genetic trait enhanced by open pollination of maize.     

Transient interface sharpening in miscible alloys

We observed that diffuse interfaces sharpen rather than broaden in completely miscible ideal binary systems. This is shown in situ during heat treatments at gradually increasing temperatures by scattering of synchrotron radiation in coherent Mo/V multilayers containing initially diffuse interfaces. This effect provides a useful tool for the improvement of interfaces and offers a way to fabricate better x-ray or neutron mirrors, microelectronic devices, or multilayers with giant magnetic resistance.     

Effects of rumen-protected oil supplementation on finishing grazing beef cattle

Tropical Animal Health and Production - The objective of this study was to evaluate the effects of rumen-protected oil (soybean and palm oil) in supplements for beef cattle during the fattening...