Template-Type: ReDIF-Article 1.0 Author-Name: A. Dreiseitl Author-Workplace-Name: Agricultural Research Institute Kroměříž, Ltd., Czech Republic Title: Adaptation of Blumeria graminis f.sp. hordei to barley resistance genes in the Czech Republic in 1971-2000 Abstract: Results of scoring the resistance of 35 selected spring barley varieties to powdery mildew, exhibiting high powdery mildew severity, in 307 variety trials of the Central Institute for Supervising and Testing in Agriculture were analysed. The varieties can be divided into two groups: the varieties that could not induce any changes in the pathogen population (the varieties with no effective resistance gene and varieties carrying gene mlo) and the varieties possessing major resistance genes [a total of 12 Ml-genes: a1, a3, a6, a7, a9, a12, a13, at, k1, La, g and (Kr)] to which the pathogen population adapted in 1971-2000. The time slope of decreasing resistance of varieties is described. The importance of individual evolutionary forces (mutations, migration, direct selection, indirect selection and recombinations) for the erosion of efficiency of respective major resistance genes and the effects of pathogen adaptation on population complexity and diversity are discussed. Keywords: Hordeum vulgare, Blumeria graminis f.sp. hordei, spring barley, powdery mildew, genetic resistance, adaptation, evolutionary forces Journal: Plant, Soil and Environment Pages: 241-248 Volume: 49 Issue: 6 Year: 2003 DOI: 10.17221/4120-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/4120-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200306-0001.txt Handle: RePEc:caa:jnlpse:v:49:y:2003:i:6:id:4120-PSE Template-Type: ReDIF-Article 1.0 Author-Name: A. Orzeszko-Rywka Author-Workplace-Name: Faculty of Agronomy, Warsaw Agricultural University, Warsaw, Poland Author-Name: S. Podlaski Author-Workplace-Name: Faculty of Agronomy, Warsaw Agricultural University, Warsaw, Poland Title: The effect of sugar beet seed treatments on their vigour Abstract: Sugar beet seeds of three varieties (Jastra, Jamira, PNMono1) were rubbed, primed, washed and primed after rubbing. All used methods of seed treatment changed pericarp characteristics such as water potential, density, moisture and content of chemicals resulting in electrical conductivity of water extract from the seeds. Seed treatments also improved the ability and rate of germination. Their efficiency was more significant in an excess and shortage of water in germination medium than in optimum water conditions. The lower the initial seed vigour, the larger the vigour improvement. Seed priming had the best effect on the course of germination. Primed seeds were most resistant to different moisture conditions during germination. The largest differences in germination ability after four days in different water conditions were 5.1 and 7.4% for primed and primed after rubbing seeds, respectively, while the difference for control ones was 26.8%. Priming also caused an increase in seed respiration intensity. Rubbing and washing removed chemicals from the pericarp, which resulted in an increase in water potential, and consequently in vigour improvement. Keywords: sugar beet, seeds, germination, vigour, treatment, priming, washing, rubbing Journal: Plant, Soil and Environment Pages: 249-254 Volume: 49 Issue: 6 Year: 2003 DOI: 10.17221/4121-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/4121-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200306-0002.txt Handle: RePEc:caa:jnlpse:v:49:y:2003:i:6:id:4121-PSE Template-Type: ReDIF-Article 1.0 Author-Name: J.I. Flores Solís Author-Workplace-Name: Mendel University of Agriculture and Forestry in Brno, Czech Republic Author-Name: P. Mlejnek Author-Workplace-Name: Mendel University of Agriculture and Forestry in Brno, Czech Republic Author-Name: K. Studená Author-Workplace-Name: Mendel University of Agriculture and Forestry in Brno, Czech Republic Author-Name: S. Procházka Author-Workplace-Name: Mendel University of Agriculture and Forestry in Brno, Czech Republic Title: Application of sonication-assisted Agrobacterium-mediated transformation in Chenopodium rubrum L Abstract: Chenopodium rubrum belongs to the plant species in which standard Agrobacterium-mediated transformation procedures remain inefficient. We demonstrate that the employment of sonication-assisted Agrobacterium-mediated transformation (SAAT) effectively enhanced transient expression of GUS gene coding for b-glucuronidase in Chenopodium rubrum. Further the results indicated that the age of seedlings is one of the limiting factors affecting the potency of Agrobacterium tumefaciens infection. Histochemical detection of b-glucuronidase activity revealed that two-days-old seedlings were much more susceptible to infection than ten-days-old ones. According to our results SAAT technology could provide an efficient tool for obtaining stable transformants when applied to two-days-old seedlings of Chenopodium rubrum. Keywords: Agrobacterium tumefaciens, strain EHA 105, uidA, GUS, b-glucuronidase Journal: Plant, Soil and Environment Pages: 255-260 Volume: 49 Issue: 6 Year: 2003 DOI: 10.17221/4122-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/4122-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200306-0003.txt Handle: RePEc:caa:jnlpse:v:49:y:2003:i:6:id:4122-PSE Template-Type: ReDIF-Article 1.0 Author-Name: K. Krofta Author-Workplace-Name: Hop Research Institute Co., Ltd, Žatec, Czech Republic Title: Comparison of quality parameters of Czech and foreign hop varieties Abstract: Market varieties of hops are classified to several groups according to their use in the brewing industry - aroma, bitter (dual-purpose), high-alpha ones. Saaz and other genetically related varieties form a separate group among the aromatic hops. The group called fine aroma hops has a low content of a-bitter acids (3-4% w/w), its content of b-bitter acids is in the range of 4-7% w/w and cohumulone ratio in the interval of 23-26% rel. The composition of hop oils is characterised by the content of b-farnesene in the range of 15-20% rel. and trans-a-bergamotene at the amount of ca. 1% rel. Most market varieties of hops are of hybrid origin. It holds true about the Czech varieties Sládek, Bor, Premiant and Agnus. The content of a-bitter acids in bitter varieties is in the range of 7-10% w/w while the content of a-bitter acids in high-alpha hops is higher than 10% w/w. Keywords: hop varieties, hop resins, hop oils, a-bitter acids, b-bitter acids Journal: Plant, Soil and Environment Pages: 261-268 Volume: 49 Issue: 6 Year: 2003 DOI: 10.17221/4123-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/4123-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200306-0004.txt Handle: RePEc:caa:jnlpse:v:49:y:2003:i:6:id:4123-PSE Template-Type: ReDIF-Article 1.0 Author-Name: V. Nesvadba Author-Workplace-Name: Hop Research Institute Co., Ltd., Žatec, Czech Republic Author-Name: J. Černý Author-Workplace-Name: Hop Research Institute Co., Ltd., Žatec, Czech Republic Author-Name: K. Krofta Author-Workplace-Name: Hop Research Institute Co., Ltd., Žatec, Czech Republic Title: Transfer of the hop (Humulus lupulus L.) alpha-bitter acid content to progenies of F1 and I1 generations in selected parental components Abstract: In the period 1999-2001 the transfer of a-acid content from selected parents to their progenies was evaluated. Four female plants (English varieties Target and Yeoman, German variety Magnum and Czech variety Premiant) and four male plants from the gene resources of male hops (82/6, 86/4, 87/3, clone 72) were chosen as the initial material. Progenies of F1 generation of Magnum and Yeoman show significantly higher a-acid content compared to the progenies of other female hops. Progenies of F1 generation of male plants 86/4 and 87/3 show significantly higher a-acid content compared to the progenies of other male plants. Progenies of I1 generation of Magnum variety and male 86/4 contain the highest amount of a-acids. Progenies of F1 generation have higher a-acid content at the 99% probability level compared to the progenies of I1 generation. Progenies of both generations show nearly the same variability. Keywords: hops, Humulus lupulus L., progenies, F1 generation, I1 generation, a-bitter acids Journal: Plant, Soil and Environment Pages: 269-276 Volume: 49 Issue: 6 Year: 2003 DOI: 10.17221/4124-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/4124-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200306-0005.txt Handle: RePEc:caa:jnlpse:v:49:y:2003:i:6:id:4124-PSE Template-Type: ReDIF-Article 1.0 Author-Name: J. Sedláková Author-Workplace-Name: Mendel University of Agriculture and Forestry in Brno, Czech Republic Author-Name: B. Kocourková Author-Workplace-Name: Mendel University of Agriculture and Forestry in Brno, Czech Republic Author-Name: L. Lojková Author-Workplace-Name: Mendel University of Agriculture and Forestry in Brno, Czech Republic Author-Name: V. Kubáň Author-Workplace-Name: Mendel University of Agriculture and Forestry in Brno, Czech Republic Title: Determination of essential oil content in caraway (Carum carvi L.) species by means of supercritical fluid extraction Abstract: Dependently on planting conditions caraway fruits contain 1-9% of essential oils consisting of about 30 compounds. Carvone and limonene account for the main portion, about 95%. To evaluate the quality of various registered caraway (Carum carvi L.) cultivars (Kepron, Prochan and Rekord) planted during 1998-2000, regarding the effect of sample grinding and preparation, plant treatment and time of harvest, the amounts of essential oil and the carvone/limonene ratio were determined. Both whole and ground caraway seeds were extracted. As obvious from the results, SFE is not suitable for the determination of essential oils in whole seeds since the results are lower in comparison with those of ground caraway. The way of grinding was also examined. Of the three mills used, a splintery mill VIPO seemed to be the most suitable. Further, the amount of essential oil was studied in caraway gathered at the beginning of maturation (sample A) and at full ripeness (sample B) of caraway seeds. It was found that the samples gathered at full ripeness (samples B) had more essential oil. It was also concluded that the use of the regulator Roundup Bioaktiv during caraway maturation to unite the ripening of achenes in the main umbel and the first-order umbels, and the use of fungicides (Alert S and Prelude 10) affected positively the amount of essential oil in caraway. Possibilities of SFE application for the essential oil determination in small samples gathered during breeding were investigated. The results were used as a one of the criteria during breeding. Classical way of the essential oil determination does not allow this option. An alternative method for the isolation and determination of essential oils - supercritical fluid extraction (SFE) - was investigated in this study. Keywords: caraway, cultivar, carvone, limonene, gas chromatography (GC), supercritical fluid extraction (SFE) Journal: Plant, Soil and Environment Pages: 277-282 Volume: 49 Issue: 6 Year: 2003 DOI: 10.17221/4125-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/4125-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200306-0006.txt Handle: RePEc:caa:jnlpse:v:49:y:2003:i:6:id:4125-PSE Template-Type: ReDIF-Article 1.0 Author-Name: J. Lachman Author-Workplace-Name: Czech University of Agriculture in Prague, Czech Republic Author-Name: E.C. Fernández Author-Workplace-Name: Czech University of Agriculture in Prague, Czech Republic Author-Name: M. Orsák Author-Workplace-Name: Czech University of Agriculture in Prague, Czech Republic Title: Yacon [Smallanthus sonchifolia (Poepp. et Endl.) H. Robinson] chemical composition and use - a review Abstract: Yacon [Smallanthus sonchifolia (Poepp. et Endl.) H. Robinson], a native plant of the Andes, belongs to the family Compositae (Asteraceae) and it represents a traditional crop of the original population of Peru used in traditional medicine. A major portion of tuberous root biomass is composed of water (> 70% of fresh weight). Saccharides, especially oligo-fructans, form 70-80% of dry weight, protein content ranges between 0.3% and 3.7%. Fructooligosaccharides of inulin type b (2®1), mainly oligomers (GF2-GF16), are known for their ability to keep the colon healthy. Yacon sweetness is predominantly caused by fructose, which is by some 70% sweeter than sucrose. Other oligosaccharides are 1-kestose and nystose. Diabetics and persons suffering from digestive problems are recommended to consume yacon because its sugars are not available from the small intestine. The mean tuberous root composition per 100 g of fresh matter is 81.3, 13.8, 0.9, 1.0, 0.1 and 1.1 g of water, saccharides, fibre, proteins, lipids and ash, respectively. Mean mineral contents per 100 g of fresh matter are 334, 34, 12, 8.4, 0.4 and 0.2 mg of potassium, phosphorus, calcium, magnesium, sodium and iron, respectively. Vitamins B1, B2, C, b-carotene and polyphenols in the same weight are present at mean concentrations 0.07, 0.31, 5.0, 0.13 and 203 mg, respectively. Yacon can be considered an industrial crop, particularly as a source of inulin. The used forms are flour, syrup, extract from tuberous roots and moreover leaf extract for the preparation of yacon infusion with hypoglycaemic effect. In yacon leaves di- and sesquiterpenes with protective effects against insects are present, among them mainly ent-kaurenic acid (ent-kaur-16-en-19-oic acid) and its derivative - 15-a-angeloyloxy-ent-kauren-19-oic acid 16-epoxide. Other components are polyphenolic antioxidants, esp. hydroxycinnamic acids and chlorogenic acid. A new antifungal melampolide - sesquiterpene lactone named sonchifolin, as well as three known melampolides, polymatin B, uvedalin and enhydrin, were isolated from leaf extracts of yacon. Three major phytoalexins were isolated: 4'-hydroxy-3'-(3-methylbutanoyl)acetophenone, 4'-hydroxy-3'-(3-methyl-2-butenyl)acetophenone and 5-acetyl-2-(1-hydroxy-1-methylethyl)benzofuran. Keywords: yacon, chemical composition, biological activity, use Journal: Plant, Soil and Environment Pages: 283-290 Volume: 49 Issue: 6 Year: 2003 DOI: 10.17221/4126-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/4126-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200306-0007.txt Handle: RePEc:caa:jnlpse:v:49:y:2003:i:6:id:4126-PSE