Template-Type: ReDIF-Article 1.0 Author-Name: Jaroslav Polák Author-Workplace-Name: Division of Plant Medicine, Department of Virology, Research Institute of Crop Production, Prague-Ruzyně, Czech Republic Author-Name: Jitka Pívalová Author-Workplace-Name: Division of Plant Medicine, Department of Virology, Research Institute of Crop Production, Prague-Ruzyně, Czech Republic Author-Name: William Dowler Author-Workplace-Name: Division of Plant Medicine, Department of Virology, Research Institute of Crop Production, Prague-Ruzyně, Czech Republic Author-Name: R. Walker Miller Author-Workplace-Name: Division of Plant Medicine, Department of Virology, Research Institute of Crop Production, Prague-Ruzyně, Czech Republic Title: Evaluation of American peach cultivars for resistance to Plum pox virus Abstract: Twenty-eight American peach cultivars were screened for their reaction to Plum pox virus (PPV). The cultivars were evaluated for the presence and intensity of PPV symptoms in leaves and fruits, and the relative concentration of PPV protein in flowers was determined by ELISA. The results allowed to divide the cultivars into four groups: cultivars Flame Prince, Cotender, Newhaven, Ruby Prince, Sun Prince, Jefferson, Camden and Jersey Queen were characterised as medium resistant to PPV; cultivars Loring, Blaze Prince, June Prince and Legend were classified as tolerant; cultivars Quachita Gold, O'Henry, Crest Haven, Biscos, Sentry, Fire Prince, Carogem, Carolina Belle, Redglobe and Harvester were rated as medium susceptible; and cultivars Bounty, Summer Prince, Gold Prince, Redhaven, Gala and Sunbrite were characterised as highly susceptible to PPV. Keywords: Plum pox virus, peach, disease symptoms, virus concentration, ELISA, resistance Journal: Plant Protection Science Pages: 1-6 Volume: 39 Issue: 1 Year: 2003 DOI: 10.17221/3819-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/3819-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200301-0001.txt Handle: RePEc:caa:jnlpps:v:39:y:2003:i:1:id:3819-PPS Template-Type: ReDIF-Article 1.0 Author-Name: Renata Fialová Author-Workplace-Name: Department of Cell Biology and Genetics, Faculty of Science, Palacký University, Olomouc-Holice, Czech Republic Author-Name: Milan Navrátil Author-Workplace-Name: Department of Cell Biology and Genetics, Faculty of Science, Palacký University, Olomouc-Holice, Czech Republic Author-Name: Pavla Válová Author-Workplace-Name: Department of Cell Biology and Genetics, Faculty of Science, Palacký University, Olomouc-Holice, Czech Republic Title: Phytoplasma occurrence in apple trees in the Czech Republic Abstract: The presence of phytoplasmas in apple trees with proliferation symptoms, rubbery wood symptoms and no symp­toms was determined by using polymerase chain reaction assays with primers amplifying phytoplasma 16S rRNA gene. Phytoplasmas were detected in all trees with proliferation symptoms. Positive tests for phytoplasma in the group of trees with rubbery wood symptoms and of those without symptoms revealed a relatively high incidence of latent phytoplasma infection. Using restriction fragment length polymorphism analysis, phytoplasma of the same identity - apple proliferation phytoplasma (subgroup 16SrX-A) - was recorded in all positively tested trees. Keywords: proliferation symptoms, rubbery wood symptoms, non-symptomatic infection, PCR, RFLP Journal: Plant Protection Science Pages: 7-12 Volume: 39 Issue: 1 Year: 2003 DOI: 10.17221/3820-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/3820-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200301-0002.txt Handle: RePEc:caa:jnlpps:v:39:y:2003:i:1:id:3820-PPS Template-Type: ReDIF-Article 1.0 Author-Name: Svetlana Šliková Author-Workplace-Name: Division of Applied Genetics and Breeding, Research Institute of Plant Production, Piešťany, Slovak Republic Author-Name: Edita Gregorová Author-Workplace-Name: Division of Applied Genetics and Breeding, Research Institute of Plant Production, Piešťany, Slovak Republic Author-Name: Pavel Bartoš Author-Workplace-Name: Division of Applied Genetics and Breeding, Research Institute of Plant Production, Piešťany, Slovak Republic Author-Name: Ján Kraic Author-Workplace-Name: Division of Applied Genetics and Breeding, Research Institute of Plant Production, Piešťany, Slovak Republic Title: Marker-assisted selection for leaf rust resistance in wheat by transfer of gene Lr19 Abstract: Cultivar Agrus, possessing a chromosomal substitution, and cultivar Sunnan, possessing a translocation from Thinopyrum ponticum (= Agropyron elongatum, 2n = 10x) with leaf rust resistance gene Lr19 against Puccinia triticina, were crossed with the susceptible winter wheat cultivars Sofia, Simona and Lívia to transfer Lr19 into agronomi­cally better genotypes by marker-assisted selection. Altogether 304 individuals of the F2 progeny were screened for endopeptidase phenotypes. We found null endopeptidase allele Ep-D1c (marker tightly liked with resistance gene Lr19) in 49 plants. The progenies of 40 plants of the F2 generation (with Ep-D1c) were reselected with the same marker and tested for leaf rust reaction. Results achieved with the isozyme marker corresponded with those of the resistance tests. We obtained 28 F3 families with resistance gene Lr19 confirmed by presence of the null endopeptidase allele and by tests for leaf rust reaction. Field tests showed that Agrus increased the height of plants in the progenies, and the smallest negative effect on yield components was observed in both crosses with cultivar Sunnan. Keywords: Puccinia triticina, leaf rust, Lr19, Triticum aestivum L., endopeptidase, marker-assisted selection Journal: Plant Protection Science Pages: 13-17 Volume: 39 Issue: 1 Year: 2003 DOI: 10.17221/3821-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/3821-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200301-0003.txt Handle: RePEc:caa:jnlpps:v:39:y:2003:i:1:id:3821-PPS Template-Type: ReDIF-Article 1.0 Author-Name: Boniface D. Kashina Author-Workplace-Name: Department of Crop Science and Production, Sokoine University of Agriculture, Morogoro, Tanzania Author-Name: Robert B. Mabagala Author-Workplace-Name: Department of Crop Science and Production, Sokoine University of Agriculture, Morogoro, Tanzania Author-Name: Anatolia A. Mpunni Author-Workplace-Name: Department of Crop Science and Production, Sokoine University of Agriculture, Morogoro, Tanzania Title: First report of Ageratum conyzoides L. and Sida acuta Burm F. as new weed hosts of Tomato yellow leaf curl Tanzania virus Abstract: Tomato farms in the Dodoma region of Tanzania where a high incidence of Tomato yellow leaf curl Tanzania virus has been reported were visited to survey for weed hosts. Weeds exhibiting symptoms of infection by the virus were collected and identified. Lysates of leaf samples of the weed species were prepared and clarified by centrifugation. The clarified sap was dotted on nylon membranes and hybridised with a DIG-labelled probe. The putative viral DNA was extracted from the samples by phenol-chloroform procedures, and amplified by polymerase chain reaction methods using a primer pair designed to amplify a 1.2 kb fragment of the virus. Strong hybridisation signals were observed when sap from Ageratum conyzoides and Sida acuta were hybridised to the labelled probe. Similarly, the expected fragment size was obtained after amplification of DNA from both samples. It is concluded that these weeds are new hosts of Tomato yellow leaf curl Tanzania virus. An extensive search for yet undiscovered weed hosts is advocated, while the practice of farm sanitation is encouraged to eliminate reservoirs of the virus and vector. Keywords: Tomato yellow leaf curl Tanzania virus, weed hosts, amplification, hybridisation Journal: Plant Protection Science Pages: 18-22 Volume: 39 Issue: 1 Year: 2003 DOI: 10.17221/3822-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/3822-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200301-0004.txt Handle: RePEc:caa:jnlpps:v:39:y:2003:i:1:id:3822-PPS Template-Type: ReDIF-Article 1.0 Author-Name: Blanka Tesařová Author-Workplace-Name: Department of Plant Protection, Czech University of Agriculture, Prague-Suchdol, Czech Republic Author-Name: Miloslav Zouhar Author-Workplace-Name: Department of Plant Protection, Czech University of Agriculture, Prague-Suchdol, Czech Republic Author-Name: Pavel Ryšánek Author-Workplace-Name: Department of Plant Protection, Czech University of Agriculture, Prague-Suchdol, Czech Republic Title: Development of PCR for specific determination of root-knot nema­tode Meloidogyne incognita Abstract: PCR primers designed from the gene sequence for the SEC 1 oesophageal gland protein were used to specifically detect and differentiate the root-knot nematode Meloidogyne incognita from other species from the genus Meloido­gyne. Amplification products were obtained from five M. incognita populations from different origins whereas DNA from M. fallax, M. javanica, M. arenaria, M. chitwoodi and M. hapla was not amplified. DNA extracted from different materials (females, root galls and spiked soil) could easily be used for M. incognita detection. One female gave sufficient amount of DNA for detection. Together with mitochondrial DNA this is one of the first attempts to use a gene outside of ITS regions for species specific PCR in the genus Meloidogyne. Keywords: root-knot nematodes, Meloidogyne incognita, PCR, diagnostics, oesophageal gland protein gene Journal: Plant Protection Science Pages: 23-28 Volume: 39 Issue: 1 Year: 2003 DOI: 10.17221/3823-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/3823-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200301-0005.txt Handle: RePEc:caa:jnlpps:v:39:y:2003:i:1:id:3823-PPS Template-Type: ReDIF-Article 1.0 Author-Name: Eva Žďárková Author-Workplace-Name: Department of Stored-Product Pest Control, Research Institute of Crop Production, Prague-Ruzyně, Czech Republic Author-Name: Jan Lukáš Author-Workplace-Name: Department of Stored-Product Pest Control, Research Institute of Crop Production, Prague-Ruzyně, Czech Republic Author-Name: Pavel Horák Author-Workplace-Name: Department of Stored-Product Pest Control, Research Institute of Crop Production, Prague-Ruzyně, Czech Republic Title: Compatibility of Cheyletus eruditus (Schrank) (Acari: Cheyletidae) and Ce­phalonomia tarsalis (Ashmead) (Hymenoptera: Bethylidae) in biological control of stored grain pests Abstract: A laboratory experiment was carried out on stored wheat infested by the stored product mite Acarus siro and beetle Oryzaephilus surinamensis. The initial infestation was 150 mites of A. siro and 15 beetles of O. surinamensis per 1 kg of wheat. The predatory mite Cheyletus eruditus and parasitoid Cephalonomia tarsalis were added in the ratio 1:20 and 1:12, repectively. Three combinations were tested: (1) mites and (2) beetles separately, and (3) mites and beetles together. The experiment ran for three months at 22°C and 75% RH. The pests were suppressed by their antagonists in all combinations. Synchronous application of both natural enemies resulted in better control of O. surinamensis through an enhanced effect of both antagonists. Keywords: Acarus siro, Oryzaephilus surinamensis, Cheyletus eruditus, Cephalonomia tarsalis, stored wheat, biological control Journal: Plant Protection Science Pages: 29-34 Volume: 39 Issue: 1 Year: 2003 DOI: 10.17221/3824-PPS File-URL: http://pps.agriculturejournals.cz/doi/10.17221/3824-PPS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pps-200301-0006.txt Handle: RePEc:caa:jnlpps:v:39:y:2003:i:1:id:3824-PPS