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• Development of a New Maize (Zea mays L.) Breeding Program

  25-30

  Pál Pepó

  Szilárd Tóth

  Views:

  253

  Genetic manipulation may not replace any conventional method in crop breeding programs, but it can be an important adjunct to them. Plant regeneration via tissue culture is becoming increasingly more common in monocots such as corn (Zea mays L.). In vitro culturability and regeneration ability of corn decreased as homozigosity increased, which suggested that these two attributes were controlled primarily by dominant gene action. Pollen (gametophytic) selection for resistance to aflatoxin in corn can greatly facilitate recurrent selection and screening of germplasm for resistance at a much less cost and shorter time than field testing. Integration of in vivo and in vitro techniques in maize breeding program has been developed to obtain desirable agronomic attributes, speed up the breeding process and enhance the genes responsible for them. The efficiency of anther and tissue cultures in most cereals such as maize and wheat have reached the stage where it can be used in breeding programs to some extent and many new cultivars produced by genetic manipulation have now reached the market.

• Q-PCR analysis of the resistance of Hungarian Botrytis cinerea isolates toward azoxystrobin

  41-44

  Anikó Szojka

  Mojtaba Asadollahi

  Éva Fekete

  Erzsébet Fekete

  Levente Karaffa

  Erzsébet Sándor

  Views:

  235

  The genes being in the mitochondrial DNA primarily encode the enzymes of cellular respiration. Fungicides belonging to the family of quinol oxidase inhibitors (QoIs) play on important role in the protection against several plant diseases caused by fungi. These fungicides bind to the cytochrome bc1 complex so they block electron transport between cytochrome b and cytochrome c1. This way these fungicides inhibit the ATP synthesis consequently they inhibit the mitochondrial respiration. The QoI resistance has two mechanisms. One of them is the point mutation of the cytochrome b gene (CYTB), e.g. the substitution of a single glycine by alanine at position 143 results in high-resistance. The other is the cyanide-resistant alternative respiration sustained by the alternative oxidase.
  In a cell there are several mitochondria. The phenomenon when the genomes of all mitochondria in the cell are identical is called homoplazmy. If in the cell there is wild and mutant mitochondrial DNA this is called heteroplasmy. Whether the mutation in the mitochondria causes fenotypical diversity or does not depend on the dose, i.e. it depends on the percentage of the changed mitochondrials. During our work we investigated Botrytis cinerea single spore isolates which have been collected in 2008-2009 on different host plants. Our goal was to decide whether heteroplasmy influences the level of resistance. We managed to detect the change of the level of heteroplasmy, so the change the level of the resistance due to the treatment with fungicide.

• Studying the reproduction-biological effect of the GPR54 receptor gene in sheep

  48-51

  Szilvia Szabó

  Mariann Árnyasi

  András Jávor

  Views:

  322

  One of the main economical problems of sheep breeding is that continual production is not possible due to the seasonality of animals. Today, genes, mutations that may develop aseasonality in sheep are extensively researched in order to make the establishment of populations capable of aseasonal estrus possible.
  According to the current knowledge, the GPR54 gene participates in the GnRH release from the hypothalamus, and thus in the alteration of the reproduction state of the organism. Our research is aimed to determine whether the GPR54 gene has allele variations that influence the proneness to aseasonal estrus in sheep in a different extent. Therefore, the GPR54 gene sequence of sheep is first examined.

• Mitochondrial DNA-based diversity study of Hungarian brown hares (Lepus europaeus Pallas 1778)

  23-29

  Noémi Soós

  Szilvia Kusza

  Views:

  288

  The brown hare being an important game species which is widespread across the European continent has been in focus of many population genetic studies. However only a few comprising researches can be found on the diversity of Central-European populations.

  The aim of our large scale long term ongoing study is to fill this gap of information on the species by describing the genetic history and structure of the brown hare populations of the area using both mitochondrial DNA markers and genomic skin and hair colour regulating genes.

  This article gives forth a part of our results concerning the mitochondrial DNA diversity of Hungarian brown hares based on amplification of a 512 bp long D-loop sequence. N=39 tissue or hair samples have been collected from 15 sampling sites on the Hungarian Great Plain. We have described a high level of haplotype diversity (Hd=0.879±0.044) based on a 410 bp alignment of our sequences. We have found 17 haplotypes within our sample set with the nucleotid diversity of π=0.01167±0.0022. Our ongoing research shows high genetic diversity for the brown hare in the studied region and a second alignment with 156 sequences downloaded from GenBank indicates a geographic pattern of haplotypes among the studied populations though these results need confirmation by our further analyses.