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A total of 123 isolates of Phytophthora infestans were recovered from 43 commercial fields and allotments of potato and tomato in Hungary. Isolates were characterised for mating type, response to metalaxyl, isozyme genotype at glucose-6-phosphate isomerase (Gpi) and peptidase A (Pep) loci, nuclear DNA fingerprint with probe RG57 and mitochondrial haplotype. Both mating types were detected in 8 potato and 3 tomato fields. The frequency of A1 and A2 were 47.5% and 52.5% on potato and 60.5% and 39.5% on tomato. More than sixty per cent of the whole population were resistant (31.1%) or responded intermediately (30.2%) to the fungicide metalaxyl in vitro. All isolates were monomorphic at the Gpi locus (100/100), but four allele combinations 100/100 (33%), 96/100 (28%), 96/96 (31%) and 83/96 (8%) were found at the Pep locus. Genotype Pep 83/96 is rare in Europe and all isolates with this allele combination were of A1 mating type and Ia mitochondrial haplotype. As in other European populations, only two of the four mitochondrial haplotypes (Ia, 32.5% and IIa, 67.5%) were detected. Diversity of RG57 fingerprints was high. Of the 79 different fingerprints found 67 were not detected previously.

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We investigated the diversity pattern of nine Swiss stone pine (Pinus cembra L.) populations along the Carpathian range including the High Tatras, by using six chloroplast DNA microsatellites (cpSSR). Our aim was to detect genetically distinct regions by clustering of populations, and to tackle possible historical colonization routes. Our analysis referred to an investigated geographical range with the two most distant populations situated at about 500 air km. We found that the most diverse populations are situated at the two edges of the investigated part, in the Retezat Mts. (South Carpathians) and the High Tatras, and diversity decreases towards the populations of the Eastern Carpathians. Hierarchical clustering and NMDS revealed that the populations of the South Carpathians with the Tatras form a distinct cluster, significantly separated from those of the Eastern Carpathians. Moreover, based on the most variable chloroplast microsatellites, the four populations of the two range edges are not significantly different. Our results, supported also by palynological and late glacial macrofossil evidences, indicate refugial territories within the Retezat Mts. that conserved rich haplotype composition. From this refugial territory Pinus cembra might have colonized the Eastern Carpathians, and this was accompanied by a gradual decrease in population diversity. Populations of the High Tatras might have had the same role in the colonizing events of the Carpathians, as positive correlation was detected among populations lying from each other at a distance of 280 km, the maximum distance between neighbouring populations.

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Genetic diversity among breeding populations is key in plant breeding programs. This study aimed to determine the extent of genetic diversity among 37 diverse maize genotypes using simple sequence repeat (SSR) markers. The maize genotypes were selected based on their variable resistance to Striga asiatica. Maize genotypes were fingerprinted using 18 polymorphic SSR markers. Marker and population diversity parameters were computed. A total of 191 alleles were detected and the number of effective alleles varied from 2 to 21 per locus with a mean of 11. The polymorphic information content (PIC) of the SSR markers varied from 0.59 to 0.96, with a mean of 0.80. Significant differences were observed among populations, individuals and within individuals. Within and among individual variances accounted for 85% and 13% of the total gene diversity. The genotypes were grouped into three main genetic clusters, which were not influenced by genotype origin. Mean genetic distance (0.43) and low geneflow (0.18) were observed among the populations. High mean genetic identity (0.65) was recorded, indicating potential genetic ‘bottleneck’ among the selected germplasm. The following open pollinated varieties; Border King, Colorado, CIMMYT’s ZM OPVs, Mac Pearl, Shesha, Nel Choice, Natal 8Lines, Nel Choice QPM, Hickory King, Kep Select, Obatanpa and the Striga resistant synthetic variety DSTRYSYN15 were selected from different clusters for breeding.

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Courier Forschungsinstitut Senckenberg 1994 178 101 105 Vasiliu-Oromulu, L. (1995): Population

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. 2003 30 383 406 Shankle, A. M. (2004): Temporary patterns in genetic population diversity of Prorocentrum micans

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and W. Celary (eds): Fauna of Mt. Babia Góra, Poland. Publikacje Komitetu Ochrony Przyrody PAN, Kraków, 11–26. Vasiliu-Oromulu, L. and Tóthmérész, B. (1995): Population diversity of Thysanoptera in Romanian

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Cereal Research Communications
Authors: P. Matušinsky, M. Váňová, L. Tvarůžek, I. Polišenská, M. Janeček and V. Smutný

. Fusarium head blight (FHB) in Flanders: population diversity, inter-species associations and DON contamination in commercial winter wheat varieties . Eur. J. Plant Pathol. 125 : 445 – 458

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MASCIE-TAYLOR, C. G. N. (1995): Human assortative mating: evidence and genetic implications. In: Boyce, A. J. and Reynolds, V. (eds): Human Populations. Diversity and Adaptations. Oxford: Oxford University Press, 86

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Magyar Pszichológiai Szemle
Authors: Tamás Bereczkei, Petra Gyuris, Panna Köves and László Bernáth

Mascie-Taylor, C. G. N. (1995) Human assortative mating: evidence and genetic implications. In Boyce, A. J., Reynolds, V. (eds) Human Populations. Diversity and Adaptations. 86-105. Oxford university press, Oxford

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. Fusarium head blight (FHB) in Flanders: population diversity, inter-species associations and DON contamination in commercial winter wheat varieties . Eur. J. Plant Pathol. 125 : 445 – 458

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