Template-Type: ReDIF-Article 1.0 Author-Name: Rym Chaouch Author-Workplace-Name: Departments of Entomology and Plant Pathology, The Ohio State University (OSU), Ohio Agricultural Research and Development Center (OARDC), Wooster, Ohio, USA Author-Name: Margaret G. Redinbaugh Author-Workplace-Name: Departments of Entomology and Plant Pathology, The Ohio State University (OSU), Ohio Agricultural Research and Development Center (OARDC), Wooster, Ohio, USA Author-Name: Mohamed Marrakchi Author-Workplace-Name: Departments of Entomology and Plant Pathology, The Ohio State University (OSU), Ohio Agricultural Research and Development Center (OARDC), Wooster, Ohio, USA Author-Name: Saskia A. Hogenhout Author-Workplace-Name: Departments of Entomology and Plant Pathology, The Ohio State University (OSU), Ohio Agricultural Research and Development Center (OARDC), Wooster, Ohio, USA Title: Genomic of the severe isolate of Maize chlorotic dwarf virus Abstract: The complete sequences of the severe isolates of Maize chlorotic dwarf virus (MCDV-S) were obtained from cDNA clones of the viral RNA. The genome is 11 785 nucleotides (nt) in length and contains one large open reading frame between nt 455 and 10 825 that encodes a polyprotein of 3458 amino acids. Computer analysis revealed several conserved protein motifs similar to other plant picorna-like viruses. Comparison of the genome sequence of MCDV-S with that of the type strain of MCDV showed high similarities despite the difference in symptoms. Keywords: plant picorna-like virus, sequence comparison, protein motif, Waikavirus Journal: Plant Protection Science Pages: 113-119 Volume: 40 Issue: 4 Year: 2004 DOI: 10.17221/469-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/469-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200404-0001.txt Handle: RePEc:caa:jnlpps:v:40:y:2004:i:4:id:469-PPS Template-Type: ReDIF-Article 1.0 Author-Name: Jaroslav Polák Author-Workplace-Name: Department of Virology, Division of Plant Medicine, Research Institute of Crop Production, Prague-Ruzyně, Czech Republic Author-Name: Michaela Chaloupková Author-Workplace-Name: Department of Virology, Division of Plant Medicine, Research Institute of Crop Production, Prague-Ruzyně, Czech Republic Author-Name: Milan Jokeš Author-Workplace-Name: Department of Virology, Division of Plant Medicine, Research Institute of Crop Production, Prague-Ruzyně, Czech Republic Title: Biological and serological procedures to detect three nepoviruses in fruit trees Abstract: Cherry leaf roll virus (CLRV), Myrobalan latent ringspot virus (MLRSV) and Strawberry latent ringspot virus (SLRSV) were transferred by budding to woody trees, hybrid Ishtara, peach cv. GF 305 and cv. Lesiberian. Three buffers with antioxidants and stabilisers: 0.01M phosphate with 1% caffeine; 0.007M phosphate-0.01M veronal with 0.01M cysteine hydrochloride and 0.007 EDTA; 0.015M phosphate with 1% nicotine and 0.066M phosphate buffer without additives were compared for their efficiency in mechanical transmission from woody sources to herbaceous hosts (Chenopodium quinoa and C. amaranticolor). 0.007M phosphate-0.01M veronal buffer with 0.01M cysteine hydrochloride, and 0.007 EDTA and 0.015M phosphate buffer with 1% nicotine were found to be the best buffers for the three nepoviruses. Both biological transmission to herbaceous assay hosts and detection by ELISA in the investigated tree are necessary to reliably detect the three nepoviruses. Biological detection is reliable from April to June, and in September and October. ELISA detection is also more difficult in July and August. The suitability of C. quinoa and C. amaranticolor to maintain CLRV, MLRSV and SLRSV was compared. C. amaranticolor plants were found to be more suitable for CLRV and SLRSV, infected plants grow over 6 months after mechanical inoculation by the nepoviruses. C. quinoa plants proved to be most suitable for maintenance of MLRSV, while C. amaranticolor is a symptomless host of MLRSV. Reinoculation with the nepoviruses is recommended in intervals of 4 to 6 months. Keywords: Cherry leaf roll virus, Myrobalan latent ringspot virus, Strawberry latent ringspot virus, mechanical transmission, herbaceous hosts, bud transmission, fruit trees, DAS-ELISA, electron microscopy Journal: Plant Protection Science Pages: 121-127 Volume: 40 Issue: 4 Year: 2004 DOI: 10.17221/468-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/468-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200404-0002.txt Handle: RePEc:caa:jnlpps:v:40:y:2004:i:4:id:468-PPS Template-Type: ReDIF-Article 1.0 Author-Name: Hanna Bryk Author-Workplace-Name: Research Institute of Pomology and Floriculture, Skierniewice, Poland Author-Name: Barbara Dyki Author-Workplace-Name: Research Institute of Pomology and Floriculture, Skierniewice, Poland Author-Name: Piotr Sobiczewski Author-Workplace-Name: Research Institute of Pomology and Floriculture, Skierniewice, Poland Title: Inhibitory effect of Pseudomonas spp. on the development of Botrytis cinerea and Penicillium expansum Abstract: The influence of antagonistic Pseudomonas spp. on the development of Botrytis cinerea and Penicillium expansum was studied in liquid cultures. Two strains of Pseudomonas spp. (B194 and B224), originally isolated from apple leaves and fruits, respectively, inhibited spore germination and germ tube elongation of B. cinerea or P. expansum. The inhibitory effect depended on the concentration of bacteria in the cultures. After a prolonged time of incubation (48-76 h) lysis and fragmentation of hyphae of both fungi was observed. In some cases the hyphae of B. cinerea developed abnormally if the bacterial strains were present - the hyphal tips were swollen and ball-shaped spore-like structures aggregated in chains were formed. Keywords: biocontrol, blue mold, gray mold, microbial interaction, mechanism of biocontrol Journal: Plant Protection Science Pages: 128-134 Volume: 40 Issue: 4 Year: 2004 DOI: 10.17221/467-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/467-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200404-0003.txt Handle: RePEc:caa:jnlpps:v:40:y:2004:i:4:id:467-PPS Template-Type: ReDIF-Article 1.0 Author-Name: Antonín Dreiseitl Author-Workplace-Name: Agrotest, Agricultural Testing, Advisory Services and Research Ltd., Kroměříž, Czech Republic Title: Virulence frequencies to powdery mildew resistance genes of winter barley cultivars Abstract: The virulence frequencies to powdery mildew resistance genes possessed by winter barley cultivars registered and newly tested in the Czech Republic were studied in 2000, 2002 and 2004. Random samples of the populations originating from winter and spring barley fields were obtained from the air by a mobile version of a jet spore sampler mounted on a car roof. Conidia were sampled by driving across the Czech Republic. Fourteen differentials, carrying 18 out of 20 currently identified resistance genes present in winter barley cultivars, were used. High virulence frequencies (85-100%) to most resistance genes were found. Lower virulence frequencies (14.1-40.1%) were found to only three resistance genes that have not been described yet; their preliminary designations are Ml(Va), Ml(Dt) and Ml(Ca). The importance of resistance of winter barley cultivars is discussed with respect to limiting the speed with which the pathogen adapts to genetic resistances possessed by commercial cultivars of both winter and spring barley, and to the necessity of lowering the costs for powdery mildew control in barley. Keywords: Blumeria graminis f.sp. hordei, Erysiphe graminis f.sp. hordei, powdery mildew, Hordeum vulgare, barley, winter cultivars, virulence frequencies, resistance genes, pathogen populations Journal: Plant Protection Science Pages: 135-140 Volume: 40 Issue: 4 Year: 2004 DOI: 10.17221/466-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/466-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200404-0004.txt Handle: RePEc:caa:jnlpps:v:40:y:2004:i:4:id:466-PPS Template-Type: ReDIF-Article 1.0 Author-Name: Ján Praslička Author-Workplace-Name: 1 Constantine the Philosopher University, Nitra, Slovak Republic; 2Slovak Agricultural University, Nitra, Slovak Republic Author-Name: Jozef Huszár Author-Workplace-Name: 1 Constantine the Philosopher University, Nitra, Slovak Republic; 2Slovak Agricultural University, Nitra, Slovak Republic Title: Influence of temperature and host plants on the development and fecundity of the spider mite Tetranychus urticae (Acarina: Tetranychidae) Abstract: Temperature plays a key role in the time needed for development of Tetranychus urticae. It developed fastest at 35°C (6.50 d) and 30°C (6.93 d), while at 15°C it took 16.23 d. The higher the temperature, the faster the development of the mite. As to host plants involved, T. urticae developed fastest on Phaseolus vulgaris (9.42 d), followed by Cucumis sativus (10.26 d) and Capsicum annuum (10.92 d). Fecundity was highest at a temperature of 30°C (89.1 eggs), and lowest at 15°C (58.6 eggs). The fecundity of female mites increased with temperatures up to 30°C, but at 35°C it had decreased (71.08 eggs). The host plant influenced female fecundity to a limited extent; the average on Phaseolus vulgaris was 79.28 eggs, 71.48 on Capsicum annuum and 71.22 on Cucumis sativus. Keywords: Tetranychus urticae, temperature, development, fecundity Journal: Plant Protection Science Pages: 141-144 Volume: 40 Issue: 4 Year: 2004 DOI: 10.17221/465-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/465-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200404-0005.txt Handle: RePEc:caa:jnlpps:v:40:y:2004:i:4:id:465-PPS Template-Type: ReDIF-Article 1.0 Author-Name: Roman Pavela Author-Workplace-Name: Department of Entomology, Division of Phytomedicine, Research Institute of Crop Production, Author-Name: Taisya Chermenskaya Author-Workplace-Name: Department of Entomology, Division of Phytomedicine, Research Institute of Crop Production, Title: Potential insecticidal activity of extracts from 18 species of medicinal plants on larvae of Spodoptera littoralis - Short Communication Abstract: Insecticidal activity of methanol extracts from 18 species of medicinal plants was tested on 3rd instar larvae of the Egyptian cottonworm (Spodoptera littoralis). All extracts were toxic to larvae. Extracts from Ocimum basilicum, Origanum majorana, Picea excelsa and Salvia officinalis were highly toxic (LC50 - 1.7, 3.6, 4.1 and 4.7 µg/ml, respectively). Extracts from Melilotus officinalis, Pinus silvestris, Taraxacum officinalis and Achillea ptarmica were moderately toxic (LC50 - 5.6, 7.3, 8.4 and 9.1µg/ml, respectively). The relative growth rate, consumption of food and conversion efficiency of the digested food were calculated. Clear correlations were found between weight increase, quantity of ingested food, and the quantity of excrements produced during the whole assay period. These results indicate an antifeedant property of the tested extracts. Keywords: plant extract, medicinal plants, Spodoptera littoralis, insecticidal activity Journal: Plant Protection Science Pages: 145-150 Volume: 40 Issue: 4 Year: 2004 DOI: 10.17221/464-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/464-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200404-0006.txt Handle: RePEc:caa:jnlpps:v:40:y:2004:i:4:id:464-PPS Template-Type: ReDIF-Article 1.0 Author-Name: Daniela Chodová Author-Workplace-Name: Division of Phytomedicine, Research Institute of Crop Production, Prague-Ruzyně, Czech Republic Author-Name: Jan Mikulka Author-Workplace-Name: Division of Phytomedicine, Research Institute of Crop Production, Prague-Ruzyně, Czech Republic Author-Name: Marie Kočová Author-Workplace-Name: Division of Phytomedicine, Research Institute of Crop Production, Prague-Ruzyně, Czech Republic Author-Name: Jaroslav Salava Author-Workplace-Name: Division of Phytomedicine, Research Institute of Crop Production, Prague-Ruzyně, Czech Republic Title: Origin, mechanism and molecular basis of weed resistance to herbicides Abstract: This review summarises information from the literature and experimental experience of the authors in research on weed resistance to herbicides. Factors conditioning the origin of resistance are described. The origin of resistant weeds to nine active ingredients with a different mode of action is presented chronologically, and the distribution of resistant weeds around the world outlined. The fundamental modes of action: reduction of the target site sensitivity, so-called "target site resistance", and the mode by which a herbicide is metabolised into inactive products, are listed. Function and genetic modifications of target sites of selected herbicides are described. Czech biotypes of resistant weeds with a mutation at codon 264 of the psbA gene encoding the D1 protein and at codon 574 of the acetolactate synthase gene are presented. Keywords: resistance to herbicides, origin and spread of resistant weeds, target site, metabolic resistance, molecular basis of resistance Journal: Plant Protection Science Pages: 151-168 Volume: 40 Issue: 4 Year: 2004 DOI: 10.17221/463-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/463-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200404-0007.txt Handle: RePEc:caa:jnlpps:v:40:y:2004:i:4:id:463-PPS Template-Type: ReDIF-Article 1.0 Author-Name: editors Title: Index Volume 40 Journal: Plant Protection Science Pages: X1 Volume: 40 Issue: 4 Year: 2004 DOI: 10.17221/7323-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/7323-PPS.html File-Format: text/html Handle: RePEc:caa:jnlpps:v:40:y:2004:i:4:id:7323-PPS