Plant Protection Science, 2000 (vol. 36), issue 4

Experimental evaluation of apricot genotypes for resistance to Plum pox virusOriginal Paper

Miroslav Glasa, Daniela Benediková, Žofia Glasová, Ivan Hričovský, Otakar Kůdela

Plant Protect. Sci., 2000, 36(4):123-127 | DOI: 10.17221/9643-PPS  

The reaction of 19 Slovak apricot cultivars and hybrids (breeding program of Research Breeding Station at Vesele) to infection by M isolates of plum pox virus (PPV-M) was evaluated. The genotypes were inoculated by grafting to naturally infected plum trees in the field and by chip-budding in the glasshouse. Monitoring of PPV infection was done over a 3 year period by visual inspection and DAS-ELISA. In the third year of evaluation the RT-PCR assay was also applied. The tested apricot genotypes differed in their reaction to PPV infection. Most of them developed mild or severe symptoms on leaves in the first year and/or next two consecutive years after...

Outbreak of a new phytoplasma disease of onion in the Czech RepublicOriginal Paper

Jaroslav Polák, Milan Jokeš

Plant Protect. Sci., 2000, 36(4):128-131 | DOI: 10.17221/9644-PPS  

In 1999, split vegetation tops in onions, cv. Stutgartska, grown in the surroundings of Prague, Bohemia, were observed. Such plants developed two or more bulbs from one originally planted. In addition, irregular and asymmetrical drying of the apical parts of outer skirts and in some cases scaling of the outer parts of divided bulbs occurred. Such divided bul bs suffered su bstantially higher damage during storage in winter; premature budding and grow the of individual parts was frequent. Further splitting of the vegetation tops into two to five parts and followed by premature budding was observed in individual parts of divided bulbs. Ultrathin sections...

Distinguishing isolates of cereal stem disease pathogens of the genus Tapesia from isolates of Fusarium and Rhizoctonia using the RAPD methodOriginal Paper

Pavel Vejl, Sylvya Skupinová, Ivana Polišenská, Marie Váňová

Plant Protect. Sci., 2000, 36(4):132-140 | DOI: 10.17221/9645-PPS  

The RAPD method (Random Amplification of Polymorphous DNA) was used to distinguish Tapesia acufonnis and T. yallundae isolates from other pathogens of wheat stem base diseases (Fusarium avenaceum, F. culmorum, F. nivale, Rhizoctonia cerealis and R. so/ani).Isolates of the fungi originated from infected wheat plants (Triticum aestivum L.) collected at various locations in the Czech Republic. Three decameric oligonucleotide-primers were selected as producing genotype-specific RAPD products. These markers...

Leaf rust occurrence in European winter wheat varieties and breeding linesOriginal Paper

Lubomír Věchet

Plant Protect. Sci., 2000, 36(4):141-146 | DOI: 10.17221/9646-PPS  

In 1998 and 1999, 52 winter wheat varieties and breeding lines originated from ten European countries were tested for their reaction to leaf rust, the inoculum was a mixture of races UN3-61SaBa and UN13-77SaBa. Twenty six varieties and lines stayed in the same group (susceptible, moderately susceptible, moderate, moderately resista nt) in both years, with the majority being moderately resistant. Of the Czech varieties Asta, Rexia and VIada stayed in the same group in both years. Some varieties moved from one group in 1998 to another in 1999. Some of the moderately resistant varieties and lines (Hereward, WW2568, P8634, Trakos, WW251 0, Asset, WW2564)...

Voltinism of the European corn borer, Ostrinia nubilalis Hbn., in PolandOriginal Paper

Ľudovít Cagáň, Grayzna Sobota, Beata Gabryš, Czeslaw Kania

Plant Protect. Sci., 2000, 36(4):147-149 | DOI: 10.17221/9648-PPS  

From 1992 to 1996 the voltinism of the European com borer, Ostrinia nubilalis Hbn., was investigated in Poland. During the study, over 6000 larvae were collected in maize stalks in autumn. In 1994, pupal cases were observed in stalks. This indicated the development of second generation adults of the pest. Pupal cases were not found in other years of the study. The difference between 1994 and the other years was found when the degree-days accumulation at base 10°C was calculated for the periods between July 1 and July 19 (daylight 15 hrs 58 min), or July 29 (daylight 15 hrs 32 min). These values were highest in 1994 and reached 246.5°C,...

Outbreak of mirid bugs (Heteroptera: Miridae) on hopsOriginal Paper

Josef Šedivý, Vladimír Řehák

Plant Protect. Sci., 2000, 36(4):150-155 | DOI: 10.17221/9647-PPS  

Outbreaks of mirid-bugs on hop in Czech hop region recurred in 1875, I 928/29, 1947/48 and 1998/99. The spectrum and importance of specific harmful mirid species varied with the type of hop-garden. Calocoris fulvomaculatus was a dominant species in pole hop-gardens. Lygus rugulipennis was a dominant pest in trellises in 1998/99, when it locally damaged more than 50% of bines. Mirid-bugs migrate to hops at temperatures over l0°C, and stay there over the growing season. Bine tops are damaged by sucking, drying back later. Bines that grow from under the sites of injury are distorted and cease twining....

Case study of host-pathogen interaction: tomato (Lycopersicon spp.)-tomato powdery mildew (Oidium lycopersici) - a reviewReview

Aleš Lebeda, Barbora Mieslerová

Plant Protect. Sci., 2000, 36(4):156-162 | DOI: 10.17221/9650-PPS  

The present paper tries to demonstrate progress and gap of knowledge in plant pathology through the tomato - tomato powdery mildew host-pathogen interaction as a model. Tomato powdery mildew (Oidium lycopersici) has caused serious damages on glasshouse tomato (Lycopersicon esculentum) crops during the last approximately 15 years. Although the absence of tcleomorph stage did not allow exact taxonomic classification of the pathogen, comparative morphological studies using light and scanning electron microscopy revealed that Oidium lycopersici might be included to the Erysiphe sect....