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Very limited information is available on the origin, diversity and evolution of Plum pox virus (PPV) 'Turkey' (T) strain. Phylogenetic analyses based on partial sequences of 421 isolates and complete genome sequences of 57 isolates, representing the geographical distribution of PPV-T in Turkey, revealed the existence of several monophyletic and, in some cases, geographically limited groups within the PPV-T strain (Ankara-Konya1-Kayseri, Ankara-Balkan, Istanbul, Konya2 and Balkan). PPV-T diversity (0.018%) was found to be greater than that of PPV strains D and Rec but lower than that of the M strain when including the newly described and divergent M-Istanbul isolates, suggesting a long evolutionary history for PPV-T. The European part of Turkey in the Balkans, close to Bulgaria where PPV was identified for the first time, appears as a likely centre of origin for PPV-T isolates. The colonization of various parts of Turkey by diverse isolates from that region, followed by secondary local spread, is the most likely scenario for the diffusion of PPV-T in Turkey.

ABSTRACT. Turkey is not only the main apricot (Prunus armeniaca)producer and exporter in the world, but it also has a wide variety of apricot germplasms, owing to its close proximity to the centers of apricot origin. However, there is little or no genetic information on many apricot cultivars that are extensively cultivated in Turkey. We examined the genetic relatedness of 25 Turkish and four exotic apricot cultivars using SSR (simple sequence repeat) markers that were either previously developed for apricot, or for peach (P. persica), a close relative of apricot. Allele diversity (with an average allele number of 6.37) at the SSR loci and the heterozygosity rates (with an average Ho value of 0.648) of these cultivars were found to be higher than in previous studies that used the same loci for apricot. This fact might be attributed to the analysis of different numbers of accessions in the different studies. No correlations were found between the genetic relatedness and the geographical distributions of these cultivars. The data reported here will assist in the prevention of confusions in the apricot propagation and breeding in Turkey. The findings can also be directly compared with other studies that used the same SSR markers on apricot.

Content: Phenolic compounds play an important role in the plant defense mechanism and are responsible for antioxidant capacity in fruits and vegetables. It is known that the phenolics can determine in the leaves of plants which are resistant/susceptible to fungal infections. Objective: This study investigated the total phenolic compounds, content of shikimic acid from 33 different apple cultivars leaves infected with Venturia inaequalis [(Cke). Wint.] cultured in Fruit Research Station, in Egirdir, Isparta, Turkey. Materials and methods: Leaves of apple cultivars were collected three times in an interval of 30 d from July to September in 2010, and analyzed using HPLC methods to detect changes in the amount of the phenolic compounds and shikimic acid. Results: Total phenolic compounds and shikimic acid in resistant/moderate susceptible apple cultivars were higher than susceptible apple cultuvars, although not statistically different between resistant and susceptible apples. The content of shikimic acid was statistically higher only in the leaves of the domestic cultivar Ankara gü zeli on all three dates. Discussion and conclusion: Recently, there have been increased studies trying to explain the resistance mechanism in plants. Natural resistance genes are investigated in some apple cultivars and new resistance varieties which have resistant genes are identified daily. Our study hold to determine the relationship between the phenolic compounds and the expression of resistance seems to be promising.

IntroductionApple scab is a major problem in both Turkish and global apple markets. This disease is responsible for a decrease in the total market value of the fruit by 70%, resulting in production losses ranging from 30% to 60% (Türkoğlu, 1978;Agrios, 1997). On average, apple producers in Turkey apply fungicides 20-30 times per season in order to control the incidence of the causal pathogen, Venturia inaequalis, which is attributed to excess environmental pollutants (Boyraz et al., 2005;Soriano et al., 2009).V. inaequalis has a high degree of genetic variability due to recombination, thus leading to selective pressures on the fungal pathogen to overcome host resistance. An example of this selective pressure leading to host plant susceptibility was observed in Golden Delicious apple varieties. During the 1900s, Golden Delicious apples were highly resistant to apple scab, whereas today this variety is considered one of the most susceptible apple varieties (Gessler et al., 2006).

Quince (Cydonia oblonga Mill.) belongs to the Rosaceae family is native to south-eastern Europa and Asia Minor. It is generally used for table consumption and processed into jam, jelly and marmalade. It is also used as dwarfing rootstock for pear cultivars. In the present study, fruit characteristics and genetic diversity of 17 quince cultivars from Turkey were investigated. For fruit characteristics, 'Bardacik' had the highest fruit weight. The highest SSC/Acidity ratio were obtained from 'Osmancik'. There was high level of variation in fruit characteristics among cultivars. In molecular analysis, totally 133 bands were obtained from 23 sequence-related amplified polymorphism (SRAP) primer combinations and 67 of them were polymorphic. Genetic similarity of 17 cultivars was between 0.78 and 1.00. Two cultivars ('Sekergevrek' and '32S04') were found to be more distinct from the other cultivars genetically. This study showed that there was low level of genetic variation most of quince cultivars grown in Turkey. SRAP markers firstly used in quince with this study indicating that it can be used for characterization and diversity analysis of quince.

Investigation of susceptibility of some apricot cultivars to shot-hole [Stigmina carpophila (Lev.) M.B. Ellis] disease under natural inoculum conditions Bazı kayısı çeşitlerinin [Stigmina carpophila (Lev.) M.B. Ellis] yaprak delen hastalığına karşı doğal inokülasyon koşullarında duyarlılığının araştırılması

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