Template-Type: ReDIF-Article 1.0 Author-Name: M. Živčák Author-Workplace-Name: Slovak Agricultural University in Nitra, Nitra, Slovak Republic Author-Name: M. Brestič Author-Workplace-Name: Slovak Agricultural University in Nitra, Nitra, Slovak Republic Author-Name: K. Olšovská Author-Workplace-Name: Slovak Agricultural University in Nitra, Nitra, Slovak Republic Author-Name: P. Slamka Author-Workplace-Name: Slovak Agricultural University in Nitra, Nitra, Slovak Republic Title: Performance index as a sensitive indicator of water stress in Triticum aestivum L. Abstract: Polyphasic chlorophyll α fluorescence represents a promising tool for detection of plant tolerance to various environmental stresses. In pot vegetation experiments, plants of seven winter wheat varieties were screened for their drought tolerance. The drought stress was initiated in plants by withholding water at the beginning of anthesis. While water content was measured continuously as relative water content (RWC), fast chlorophyll α fluorescence kinetics was measured and analysed on dehydrating intact leaves by the JIP-test (analysis of O-J-I-P fluorescence transient). Maximum quantum efficiency of PS II photochemistry (FV/FM) parameter was almost unaffected by dehydration until the severe water stress occurred. In contrast to this a continuous decrease of performance index (PIabs) parameter (Strasser et al. 1995) was observed from the very beginning of dehydration following the decrease of RWC. Statistically significant differences were also found in the PIabs parameter among all tested varieties. The results show that PIabs may serve as an index of plant/variety vitality and/or sensitivity to water stress reflecting their different drought tolerance. Keywords: chlorophyll a fluorescence, drought, drought tolerance, photosynthesis, photosystem II, Triticum aestivum L Journal: Plant, Soil and Environment Pages: 133-139 Volume: 54 Issue: 4 Year: 2008 DOI: 10.17221/392-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/392-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200804-0001.txt Handle: RePEc:caa:jnlpse:v:54:y:2008:i:4:id:392-PSE Template-Type: ReDIF-Article 1.0 Author-Name: H. Tang Author-Workplace-Name: Department of Horticulture, College of Forestry and Horticulture, Sichuan Agricultural University, Sichuan, P. R. China Author-Name: Y. Luo Author-Workplace-Name: Department of Horticulture, College of Forestry and Horticulture, Sichuan Agricultural University, Sichuan, P. R. China Author-Name: C. Liu Author-Workplace-Name: Department of Horticulture, College of Forestry and Horticulture, Sichuan Agricultural University, Sichuan, P. R. China Title: Plant regeneration from in vitro leaves of four commercial Pyrus species Abstract: An efficient shoot regeneration from in vitro leaf sections of Pyrus communis Bartlett, P. pyrifolia Shenbuzhi, P. bretschneideri Zaosu and P. ussuriensis Manyuanxiang was successfully developed for use in future transgenic studies. On the basis of regeneration frequency and average shoot numbers, optimal shoot regeneration was obtained on leaf sections of P. communis Bartlett when cultured on Murashige and Skoog complete medium containing 6.0 mg/l BA (6-benzyladenine) and 0.1 mg/l NAA (α-naphthaleneacetic acid), while Quoirin and Lepoivre complete medium supplemented with 1.0 mg/l TDZ [thidiazuron (N-phenyl-N1-1,2,3-thiadiazol-5-ylurea)] and 0.1 mg/l NAA was found best for P. pyrifolia Shenbuzhi, and Nitsch and Nitsch complete medium containing 3.0 mg/l TDZ and 0.1 mg/l NAA or 0.2 mg/l IAA was suitable forP. bretschneideri Zaosu or P. ussuriensis Manyuanxiang, respectively. After cutting the leaves into three sections perpendicular to the midrib and culturing under the equivalent conditions, regeneration occurred more frequently on basal sections than middle sections, and no shoots formed on apical sections. A ratio of NH+4-N/NO-3- N of 1:2~1:7 was found beneficial for shoot regeneration. 75.0-87.5% of proliferating shoots formed roots after 4 weeks of transfer to 1/4 strength of Murashige and Skoog complete medium supplemented with 2.5 mg/l IBA (indole-3-butryric acid) and 30.0 g/l sucrose. Regenerated plants were successfully established under greenhouse conditions. Keywords: Keywords: adventitious shoot, leaf explant, organogenesis, pear, caulogenesis, Pyrus Journal: Plant, Soil and Environment Pages: 140-148 Volume: 54 Issue: 4 Year: 2008 DOI: 10.17221/389-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/389-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200804-0002.txt Handle: RePEc:caa:jnlpse:v:54:y:2008:i:4:id:389-PSE Template-Type: ReDIF-Article 1.0 Author-Name: M. Gryndler Author-Workplace-Name: Institute of Microbiology of the Academy of Science of the Czech Rrepublic, v.v.i., Prague, Czech Republic Author-Name: K. Krofta Author-Workplace-Name: Hop Research Institute Co. Ltd., Žatec, Czech Republic Author-Name: H. Gryndlerová Author-Workplace-Name: Institute of Microbiology of the Academy of Science of the Czech Rrepublic, v.v.i., Prague, Czech Republic Author-Name: L. Soukupová Author-Workplace-Name: Institute of Microbiology of the Academy of Science of the Czech Rrepublic, v.v.i., Prague, Czech Republic Author-Name: H. Hršelová Author-Workplace-Name: Institute of Microbiology of the Academy of Science of the Czech Rrepublic, v.v.i., Prague, Czech Republic Author-Name: J. Gabriel Author-Workplace-Name: Institute of Microbiology of the Academy of Science of the Czech Rrepublic, v.v.i., Prague, Czech Republic Title: Potentially dangerous fusarioid microorganisms associated with rot of hops (Humulus lupulus L.) plants in field culture Abstract: Several fusarioid microorganisms were isolated as potential pathogens of hop (Humulus lupulus L.) but their virulence was not proved in inoculation trials in field conditions. Molecular search for other possible pathogens was then performed. Using terminal restriction fragment length polymorphism (TRFLP), Gibberella pulicaris (anamorph: Fusarium sambucinum) was identified as a probable cause of the hop wilting. The primary cause of the disease is wounding of hop crowns by feeding of rosy rustic moth (Hydraecia micacea) caterpillars or by defect pruning and other unfavourable circumstances. The specific primer HLf1 was designed that can be used to detect the pathogen in soil and in damaged plant tissues. Keywords: Humulus lupulus L., bine wilt, rootstock, DNA, artificial infection, fusarium canker, soil microflora Journal: Plant, Soil and Environment Pages: 149-154 Volume: 54 Issue: 4 Year: 2008 DOI: 10.17221/387-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/387-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200804-0003.txt Handle: RePEc:caa:jnlpse:v:54:y:2008:i:4:id:387-PSE Template-Type: ReDIF-Article 1.0 Author-Name: K.B. Sujatha Author-Workplace-Name: Indian Agricultural Research Institute, New Delhi, India Author-Name: D.C. Uprety Author-Workplace-Name: Indian Agricultural Research Institute, New Delhi, India Author-Name: D. Nageswara Rao Author-Workplace-Name: Indian Agricultural Research Institute, New Delhi, India Author-Name: P. Raghuveer Rao Author-Workplace-Name: Indian Agricultural Research Institute, New Delhi, India Author-Name: N. Dwivedi Author-Workplace-Name: Indian Agricultural Research Institute, New Delhi, India Title: Up-regulation of sucrose-P synthase in rice under elevated carbon dioxide and temperature conditions Abstract: Basmati rice (Oryza sativa L.) cultivars viz. PRH-10 (pusa rice hybrid-10) and PS-2 (Pusa Sugandh-2) were grown under two different day/night temperatures (31/24°C, 35/28°C) at ambient (370 μmol/mol) and elevated (550 μmol/mol) carbon dioxide (CO2) concentration, respectively, to characterize how an increase in CO2 and temperature affects rice photosynthesis and carbohydrate metabolism. At elevated CO2, the photosynthetic rates increased under both the temperature regimes, compared with plants grown at ambient CO2. The photosynthetic rate, sucrose-P synthase (SPS) activity and accumulation of soluble sugars and starch were higher in PRH-10 (pusa rice hybrid-10), compared to PS-2 (Pusa Sugandh-2). Elevated temperature decreased the photosynthetic rates both under ambient and elevated CO2 conditions. The SPS (sucrose-P synthase) activity and the accumulation of soluble sugars and starch were enhanced at elevated CO2 under both temperature regimes compared with plants grown at ambient CO2. The up-regulation of SPS (sucrose-P synthase) under elevated CO2 and temperature would be beneficial for growth and productivity of rice plants for the future climatic conditions. Keywords: soluble sugars, starch, basmati rice Journal: Plant, Soil and Environment Pages: 155-162 Volume: 54 Issue: 4 Year: 2008 DOI: 10.17221/388-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/388-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200804-0004.txt Handle: RePEc:caa:jnlpse:v:54:y:2008:i:4:id:388-PSE Template-Type: ReDIF-Article 1.0 Author-Name: E. Popelářová Author-Workplace-Name: Department of Microbiology, Nutrition and Dietetics, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Prague, Czech Republic Author-Name: K. Voříšek Author-Workplace-Name: Department of Microbiology, Nutrition and Dietetics, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Prague, Czech Republic Author-Name: S. Strnadová Author-Workplace-Name: Department of Microbiology, Nutrition and Dietetics, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Prague, Czech Republic Title: Relations between activities and counts of soil microorganisms Abstract: Microbial activities and counts of microorganisms were monitored as a part of research projects at 11 localities on arable land of different soil types during the years 2002-2006. The counts of microorganisms (total bacteria count, actinomycetes, micromycetes, Azotobacter, oligotrophic and spore-forming bacteria) and microbial activities (respiration, ammonification and nitrification tests) were evaluated using summary statistics, analysis of variance and correlation coefficients. The average counts of microorganisms corresponded with usual counts of microbes in arable soils. There were only some differences among localities in Azotobacter counts. Soil respiration is very often used as an indicator of soil microflora activity. Average values of basal respiration were slightly lower (0.45 mg CO2 /h per 100 g dry soil) than usual values, potential respiration with glucose (G) or with ammonium and G (NG) responded to usual values (average G 4.27, NG 9.53 mg CO2 /h per 100 g dry soil). All activities (except actual ammonification) were higher in spring season, but the differences were not significant. There were significant differences in correlation coefficients among the selected criteria; 66% from the total number of correlation coefficients were non-significant, 34% were significant (13% of them was at the significance level 0.05, 10% P < 0.01, and 11% P < 0.001). Keywords: respiration, ammonification, nitrification, bacteria, fungi, correlation coefficient, soil Journal: Plant, Soil and Environment Pages: 163-170 Volume: 54 Issue: 4 Year: 2008 DOI: 10.17221/390-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/390-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200804-0005.txt Handle: RePEc:caa:jnlpse:v:54:y:2008:i:4:id:390-PSE Template-Type: ReDIF-Article 1.0 Author-Name: M. Skwierawska Author-Workplace-Name: University of Warmia and Mazury in Olsztyn, Olsztyn, Poland Author-Name: L. Zawartka Author-Workplace-Name: University of Warmia and Mazury in Olsztyn, Olsztyn, Poland Author-Name: B. Zawadzki Author-Workplace-Name: University of Warmia and Mazury in Olsztyn, Olsztyn, Poland Title: The effect of different rates and forms of sulphur applied on changes of soil agrochemical properties Abstract: A three-year field experiment was conducted from 2000 to 2002 in North-East Poland. Each year three sulphur fertilization rates in the form of sulphate (S-SO2-4) and pure (S-S0) sulphur were applied: 40, 80 and 120 kg/ha. In the soil horizon at the depth of 0-40 cm the triple rate of S- and S-S0) depressed soil reaction. Acidification of soil caused by S-SO2-4 became evident already in the first year of the study while that resulting from S-S0) application appeared as late as in the third year. The effect of sulphur on soil in the 40-80 cm horizon was irregular. As the sulphur rates increased and the duration of the experiment progressed, sulphates accumulated in soil. In the 0-40 cm soil layer, the increasing rates of sulphur tended to increase the content of N-NH+4. In most objects, the NPK + S fertilization, and especially the single S-SO2-4 treatment, caused an increase in N-NO-3 in both soil layers compared with the NPK fertilized object. The dose of 120 kg/ha S-SO2-4 caused a significant increase in the concentration of available phosphorus in soil in the 0-40 and 40-80 cm layers. Keywords: soil, sulphur, sulphate, soil pH, nitrogen, available phosphorus, potassium Journal: Plant, Soil and Environment Pages: 171-177 Volume: 54 Issue: 4 Year: 2008 DOI: 10.17221/391-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/391-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200804-0006.txt Handle: RePEc:caa:jnlpse:v:54:y:2008:i:4:id:391-PSE