Template-Type: ReDIF-Article 1.0 Author-Name: Václav KŮDELA Author-Workplace-Name: Division of Plant Health, Crop Research Institute, Prague-Ruzyně, Czech Republic Author-Name: Václav KREJZAR Author-Workplace-Name: Division of Plant Health, Crop Research Institute, Prague-Ruzyně, Czech Republic Author-Name: Jiban Kumar KUNDU Author-Workplace-Name: Division of Plant Health, Crop Research Institute, Prague-Ruzyně, Czech Republic Author-Name: Iveta PÁNKOVÁ Author-Workplace-Name: Division of Plant Health, Crop Research Institute, Prague-Ruzyně, Czech Republic Author-Name: Petr ACKERMANN Author-Workplace-Name: State Phytosanitary Administration, Brno, Czech Republic Title: Apple burrknots involved in trunk canker initiation and dying of young trees Abstract: Conditions associated with an unusually high occurrence of burrknots in two young commercial apple orchards at two locations, Těšetice and Stošíkovice, South Moravia, the Czech Republic, were analysed. In the first orchard, planted in spring 2003, the occurrence of burrknot on trees of cvs. Early Smith, Jonagold and Gala on M.9 rootstock was evaluated. In the second orchard, planted in autumn 2002, cv. Gala on M.9 rootstock was assessed. Planting material used at each location was obtained from the same commercial propagator and had been established from the same propagation stock materials. Of 60 trees per cultivar surveyed in the first orchard, incidence of burrknots in cvs. Early Smith, Jonagold and Gala trees was 98, 97 and 92%, respectively. The burrknot severity (mean number of burrknots on above portion of rootstock) was significantly higher on Jonagold trees, i.e. 3.65, than on the other two cultivars. Of 60 Gala trees in the second orchard, symptoms of burrknot appeared on 73.3% of trees planted on a slight slope and 70.0% of trees planted on a plane. The burrknot severity was significantly higher on the Gala trees planted in the Těšetice orchard than in the Stošíkovice location. Burrknot incidence and incidence of root-suckers were the highest on Jonagold trees at Těšetice. However, correlations between burrknot number and number of root-suckers were not statistically significant. Five years after the tree planting, increased dying of Jonagold trees was recorded at Těšetice. Of 290 trees examined, 5.5% had died. On the rootstock portion of trunk, each dead tree exhibited burrknots associated with bark cankers that more or less girdled the trunks. Only sporadic occurrence of canker symptoms and no premature dying of young trees were observed at Stošíkovice. Attempts at isolation of the fire blight bacterium, Erwinia amylovora, and oomycete Phytophthora spp. from necrotic tissue surrounding burrknots on rootstocks were not successful. The stem associated apple tree viruses Apple stem pitting virus (ASPV) and Apple stem grooving virus (ASGV) were detected frequently in the rootstock and scion parts of cvs. Jonagold and Early Smith and less frequently in Gala cultivar. The virus positive trees included individuals both with various burrknot severity and without symptoms of burrknots. There were no correlations between the incidence of burrknots and the presence of ASPV and ASGV. Keywords: burrknot, apple tree, M.9 rootstock, root-suckers, trunk canker, ASPV, ASGV Journal: Plant Protection Science Pages: 1-11 Volume: 45 Issue: 1 Year: 2009 DOI: 10.17221/38/2008-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/38/2008-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200901-0001.txt Handle: RePEc:caa:jnlpps:v:45:y:2009:i:1:id:38-2008-PPS Template-Type: ReDIF-Article 1.0 Author-Name: Ivana Šafránková Author-Workplace-Name: Mendel University of Agriculture and Forestry in Brno, Faculty of Agronomy, Department of Crop Science, Breeding and Plant Medicine, Brno, Czech Republic Author-Name: Jiří Müller Author-Workplace-Name: Brno, Czech Republic Title: Peronospora hariotii on Buddleja in the Czech Republic Abstract: A downy mildew was observed on Buddleja × weyeriana Weyer ex Rehd. (B. davidii × globosa) cv. Sungold in a nursery in the northern part of the Czech Republic in July 2008. This downy mildew disease of Buddleja (Butterfly Bush) had been unknown in the country so far. Characteristics of visual symptoms and microscopic features are described. The morphology of the fungus was typical for Peronospora hariotii, conforming to the published description by GÄUMANN (1919). The sexual stage was not found. This is the first report of Peronospora hariotii causing leaf spot disease on Buddleja in the Czech Republic. Keywords: downy mildew, Peronospora hariotii, Butterfly Bush, Buddlej Journal: Plant Protection Science Pages: 12-15 Volume: 45 Issue: 1 Year: 2009 DOI: 10.17221/44/2008-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/44/2008-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200901-0002.txt Handle: RePEc:caa:jnlpps:v:45:y:2009:i:1:id:44-2008-PPS Template-Type: ReDIF-Article 1.0 Author-Name: Libor JANKOVSKÝ Author-Workplace-Name: Department of Forest Protection and Wildlife Management, Faculty of Forestry and Wood Technology, Mendel University of Agriculture and Forestry in Brno, Brno, Czech Republic Author-Name: Dagmar PALOVČÍKOVÁ Author-Workplace-Name: Department of Forest Protection and Wildlife Management, Faculty of Forestry and Wood Technology, Mendel University of Agriculture and Forestry in Brno, Brno, Czech Republic Author-Name: Miloň DVOŘÁK Author-Workplace-Name: Department of Forest Protection and Wildlife Management, Faculty of Forestry and Wood Technology, Mendel University of Agriculture and Forestry in Brno, Brno, Czech Republic Author-Name: Michal TOMŠOVSKÝ Author-Workplace-Name: Department of Forest Protection and Wildlife Management, Faculty of Forestry and Wood Technology, Mendel University of Agriculture and Forestry in Brno, Brno, Czech Republic Title: Records of Brown spot needle blight related to Lecanosticta acicola in the Czech Republic Abstract: There are two records of brown spot needle blight caused by L. acicola in the Czech Republic up to date. Disease was first reported on June 2007 in National Nature Reserve (NNR) Červená Blata, South Bohemia. A more recent discovery of L. acicola took place on August 2008 in the NNR Borkovická Blata. The disease was observed on 10-60 year old Pinus rotundata. Both locations with infected trees are situated inside nature conservation sites under strict protection regimes that are located approximately 50 km apart. In both sites, L. acicola occurred simultaneously with Dothistroma septospora, the red band needle blight causal agent on Scots pine (Pinus sylvestris), bog pine (P. rotundata) and their hybrid (P. × digenea). However, infections of both diseases on the same tree have not yet been observed. Keywords: Lecanosticta acicola, brown spot needle blight, bog pine, Pinus uncinata Journal: Plant Protection Science Pages: 16-18 Volume: 45 Issue: 1 Year: 2009 DOI: 10.17221/39/2008-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/39/2008-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200901-0003.txt Handle: RePEc:caa:jnlpps:v:45:y:2009:i:1:id:39-2008-PPS Template-Type: ReDIF-Article 1.0 Author-Name: George B. Swella Author-Workplace-Name: Tanzania Official Seed Certification Institute, Morogoro, Tanzania Author-Name: Deus M. K. Mushobozy Author-Workplace-Name: Department of Crop Science and Production, Sokoine University of Agriculture, Chuo Kikuu, Morogoro, Tanzania Title: Comparative susceptibility of different legume seeds to infestation by cowpea bruchid Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae) Abstract: The comparative susceptibility of seeds of ten legumes to infestation by Callosobruchus maculatus was studied in choice and no-choice experiments. Cowpea, garden pea and pigeon pea seeds recorded the significantly highest number of eggs oviposited and percentage adult emergence, the shortest developmental period, highest susceptibility indices and the highest weight loss. In a choice experiment, treatments which had a cowpea mixture recorded the maximum number of eggs deposited on that legume. The order for ovipositional preference for all legume seeds remained almost the same irrespective of the host on which C. maculatus had been reared. Also, there was no association between the seeds preferred for oviposition and culture on which the bruchid was reared. Cowpea and pigeon pea seeds were found to be highly susceptible to C. maculatus, whereas common bean, black gram and chickpea seeds were the least susceptible. Keywords: C. maculatus, legume seeds, oviposition, development, susceptibility, host, selection, weight loss Journal: Plant Protection Science Pages: 19-25 Volume: 45 Issue: 1 Year: 2009 DOI: 10.17221/525-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/525-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200901-0004.txt Handle: RePEc:caa:jnlpps:v:45:y:2009:i:1:id:525-PPS Template-Type: ReDIF-Article 1.0 Author-Name: Geoff R. Dixon Author-Workplace-Name: Chairman International Clubroot Working Group, January 2009 Title: Report on Plasmodiophorids and Related Organisms - An International Workshop held on 23rd August 2008, Torino, Italy (as a part of ICPP 2008) Journal: Plant Protection Science Pages: 25-38 Volume: 45 Issue: 1 Year: 2009 DOI: 10.17221/524-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/524-PPS.html File-Format: text/html Handle: RePEc:caa:jnlpps:v:45:y:2009:i:1:id:524-PPS