Plant Protection Science, 2003 (vol. 39), issue 1
Evaluation of American peach cultivars for resistance to Plum pox virus
Jaroslav Polák, Jitka Pívalová, William Dowler, R. Walker Miller
Plant Protect. Sci., 2003, 39(1):1-6 | DOI: 10.17221/3819-PPS 
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,...
Phytoplasma occurrence in apple trees in the Czech Republic
Renata Fialová, Milan Navrátil, Pavla Válová
Plant Protect. Sci., 2003, 39(1):7-12 | DOI: 10.17221/3820-PPS
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.
Marker-assisted selection for leaf rust resistance in wheat by transfer of gene Lr19
Svetlana Šliková, Edita Gregorová, Pavel Bartoš, Ján Kraic
Plant Protect. Sci., 2003, 39(1):13-17 | DOI: 10.17221/3821-PPS
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...
First report of Ageratum conyzoides L. and Sida acuta Burm F. as new weed hosts of Tomato yellow leaf curl Tanzania virus
Boniface D. Kashina, Robert B. Mabagala, Anatolia A. Mpunni
Plant Protect. Sci., 2003, 39(1):18-22 | DOI: 10.17221/3822-PPS
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...
Development of PCR for specific determination of root-knot nematode Meloidogyne incognita
Blanka Tesařová, Miloslav Zouhar, Pavel Ryšánek
Plant Protect. Sci., 2003, 39(1):23-28 | DOI: 10.17221/3823-PPS
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...
Compatibility of Cheyletus eruditus (Schrank) (Acari: Cheyletidae) and Cephalonomia tarsalis (Ashmead) (Hymenoptera: Bethylidae) in biological control of stored grain pests
Eva Žďárková, Jan Lukáš, Pavel Horák
Plant Protect. Sci., 2003, 39(1):29-34 | DOI: 10.17221/3824-PPS
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...