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Rezistence jabloní vůči Venturia inaequalis, původci strupovitosti jabloně
Strouhal, Petr
Apples belong to the most important fruit species grown in a temperate zone. Like most cultivated botanical species, the domestic apple (Malus dometica Borkh.) is attacked by a number of pathogens. Apple scab caused by fungal pathogen Venturia inaequalis (Cooce) G. Winter belongs to the world's most important diseases of the apples. Chemical protection, which is based on the application of up to 20 treatments per vegetation in intensive orchards, represents a costly entry into the production of apples. Growing of apple scab resistant varieties is part of integrated plant protection and it is one of the ways to eliminate the negative effects of fungicides use on apple quality and on the environment and simultaneously produce quality and well-sold fruit. Therefore, the aim of the bachelor thesis is to elaborate a study focused on the issue of genetic mechanisms of resistance of apples to scab. The breeding of resistant apple varieties is based on two different genetic principles. The first principle is polygen-determined resistance, which is usually racially unspecific and persistent. However, donors of this resistance are difficult to define and the breeding process is significantly slower. Another option is racially-specific resistance controlled by some of the Rvi majorogens. Up to now, 18 different Rvi genes and their donors have been described. However, in apple resistant breeding, genes Rvi2, Rvi4, Rvi5, Rvi6 and Rvi10 are mainly used. But most of resistant varieties carry only gene Rvi6. The first varieties with resistance based on gene A were bred in the 1970s in the USA. In the Czech Republic, several dozen resistant varieties have been produced since 1980, mainly due to breeding programs in Station of apple breeding for disease resistence Institute of Experimenta Botany AS CR in Strizovice and in Research and Breeding Institute of Pomology. Holovousy Ltd. Most Moravian and Silesian farmers indicate the cultivation of at least one resistant variety. Nevertheless, it is clear from the data of the Czech Statistical Office that between 2012 and 2016 there was a significant decrease in the area of the two most common resistant varieties Topaz and Rubinola. The cause of this fact may be the breakdown of Rvi6 gene controlled resistance, the planting of other resistant varieties on significantly smaller areas, or lower fruit quality of resistant varieties. The occurrence of new V. inaequalis races has influenced the breeding strategies so that the breeding targets are resistant varieties with pyramidation of several majorgenes and polygenic resistance mechanism to scab.
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Vyhodnocení výskytu patogenů jabloně na lokalitě Lysice
Pavlíčková, Kristýna
In the Czech Republic and around the world are the most commonly grown fruit trees, apple trees. The yield and also its quality is dependent on the weather, location, but also largely on the proper protection against harmful organisms. The thesis contains an overview of the most important viral, bacterial and fungal pathogens, mainly the work is focuses on the agent of apple scab, Venturia inaequalis. In the locality Lysice were evaluated attacked three major fungal pathogens: Venturia inaequalis, Podosphaera leucotricha and Monilinia fructigena, on the varieties ´Idared´, ´Jonagold´, ´Rubín´ and ´Šampion´. The attack of leaves by agent of the apple scab was the most evident in the varieties ´Rubín´ and ´Jonagold´ for which was established middle occurrence class of pathogen. The attack of fruits was minimal, because protection was made correctly. For all varieties was evaluated high frequency of apple powdery mildew, while primary infection (15 to 53 % of monitored leaves). Due to the application of chemical protection were secondary infections weaker (19 to 37 % of monitored leaves) than primary infections. By Monilinia fructigena was the most attacked variety ´Rubín´ (56 % of monitored fruits). The variety ´Rubín´ was the most sensitive for all the evaluated pathogens. For particular pathogens was devised suitable protection system.
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Studium a hodnocení rezistentních odrůd jabloní vůči houbovým chorobám
Dušek, Martin
This thesis includes experimental period 2014. In this work were evaluated 13 genotypes and 9 varieties of apple hybrids which was bred on Research and Breeding Institute of Pomology Holovousy Ltd. In this case was evaluated resistance against two diseases: apple scab (Venturia inequalis Cke. Wint.) and Powdery mildew (Podosphaera leucotricha Ell.et. Ewerk). Most of the genotypes and the varieties were moderately damaged strupovitostí Apple, thanks to the high average annual precipitation. The most susceptible genotypes and species were HL 18, HL 91, HL 204, HL 384, ' Flordika ' and ' Dima '. Apple powdery mildew is the most effect for genotype HL 204, HL 211, HL 623, HL 1132, 'Mivibe','Pidi' and 'Zita'. On growth and forage were evaluated by the characters. At the next step were evaluated growth and harvesting characters. At the end were assesed the organoleptic characters by tasting.
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Sloupcové tvary jabloní, jejich charakteristika a praktické možnosti využití
Tomková, Denisa
Wall planting was founded on 17. 3. 2008 in the clip 2,5 m x 1,00 m. By planting varieties were used 'Pidi', 'Polka', 'Elegance', 'Sonet', 'Rondo', 'Goldcats', 'Starcats', 'Suncats' and as a control variety 'Golden Delicious'. The varieties were bred at breeding workplaces VŠÚO Holovousy, ÚEB Střížovice. The set of varieties of CATS in the Research Institute Geisenheim in Germany, bred by Professor Jacob. The evaluation focused on growth, harvesting and health data. Growth data were focused on tree height, annual increases. Harvesting data focused on the number of flowers and monitor the number and weight of fruit harvested. Medical data evaluated the incidence of fungal diseases. Finally, was designed by a group of varieties suitable for cultivation practice.
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Ontogenická rezistence k Venturia inaequalis (Cke.) Wint.
Korbelová, Pavla
The Bachelor Work describes the disease of apple scab and characterises the originator of this disease - the fungus Venturia inaequalis. The possibilities of both direct and indirect protection are mentioned. The work concentrates on breeding for resistance, particularly with the use of the gene Vf (Rvi6), including the problems connected with breaking through the resistance by physiologic races of the pathogen. The emphasis is placed on ontogenic resistance, ie. the resistance influenced by age as the ability of all plants or their parts to resist and tolarate the disease in connection with the age and maturation of the host tissues. Young apple tree leaves can be susceptible to apple scab (Venturia inaequalis) but when full-grown they become more resistant to the infection. The practical use of ontogenic resistance lies in the potential for the breeding of resistant varieties, the introduction of which into cultivation will have a positive effect on agricultural yield and will also bring great benefits to agriculturists.
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Význam a možnosti ekologického uplatnění rezistentních odrůd jabloní
Havlíková, Marta
This work focuses on the most common fungal diseases affecting apple trees -- apple scab and powdery mildew. Moreover, this thesis deals with the issue of breeding of resistant varieties, with our most important breeding workplaces and with their bred varieties. The practical part of this work describes the foundation of the experiment and the results of the observation of particular varieties grown on an experimental area in the village Vrtěžíř. The experiment was based on a regular observation of the development of fungal diseases at resistant and non-resistant varieties during the whole growing season. The final part introduces options which can help an agroculturist prevent breaking the resistance.
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