Publications

Allelic diversity of the S-locus is attributed to the genetic relationships among genotypes and sexual reproduction strategy. In otherwise self-incompatible Prunus species, the emergence of loss-of-function in S-haplotypes has resulted in self-compatibility. This information may allow following major stages of crop history. The genetic diversity in the S-locus of local apricots (Prunus armeniaca L.) from different oasis ecosystems in Morocco and the comparison of the occurrence and frequency of S-alleles with other regions may allow testing the validity of previous theories on the origin and dissemination of North African apricots. The S-genotypes of 55 Moroccan apricot accessions were determined, resulting in 37 self-compatible genotypes, from which 33 were homozygotes for self-compatibility. SC was the most frequent S-allele in this germplasm, followed by S13, S7, S11, S2, S20, S8, and S6. New approaches (CAPS or allele-specific PCR) were designed for a reliable verification of the rare or unexpected alleles. The frequency and distribution of the S-alleles differed among the oases. Some of these alleles, S8, S11, S13 and S20, were formerly detected only in the Irano Caucasian germplasm and are not present in Europe. Our data supports the Irano-Caucasian origin of the Moroccan apricots and their original introduction by Phoenicians and Arabs through the North African shore. North Africa seems to have preserved much higher variability of apricot as compared with Europe. The loss of genetic diversity in apricot might be explained by the occurrence of self-compatibility and the length of time that apricot has spent with this breeding system in an environment without its wild relatives, such as the Moroccan oases or Central Europe.

Experts of risk analysis aim to help decisions with efficient information. The decision itself is not included in their duties; nevertheless, they are responsible for confronting the decision makers with the expected consequences of their decisions. To this high standard data gained by modelling or monitoring are needed. Most of them have not yet been collected and integrated in a unique data system. One of the aims of this paper is to call the attention to the importance of common data management and joint research projects between different disciplines with a methodical summary.

Fruit crops have a growing economic importance worldwide and molecular genetics might be useful in solving many problems that arise during commercial production. One of the fields that have attracted intense attention is the molecular basis of self-incompatibility that may result in low fruit set. In tree fruits of the Rosaceae family, the incompatibility reactions take place between the pistil S-ribonuclease (S-RNase) and the pollen-expressed S-haplotype specific F-box (SFB) proteins. In most cases, the loss of self-incompatibility was associated with mutations in the S-RNase or SFB genes. A total of 27 non-functional S-haplotypes have been identified and characterized, most (24) of which emerged as a consequence of natural mutations. In the Prunoideae, most haplotypes are pollen-part mutants (50 %), while 8 are stylar-part mutants (36 %), one haplotype shows both pollen- and stylar-part mutations, and molecular changes for two haplotypes still have not been clarified. In contrast, non-functional natural haplotypes in the Maloideae are all stylar-part mutants. The analysis of such mutants may shed light on underlying molecular mechanisms as was the case with the establishment of the general inhibitor model that describes interactions between pollen and pistil S-proteins. However, several other molecules were supposed to contribute to the molecular interactions, at least in Solanaceae, a family with a similar self-incompatibility system. This review also endeavours to delineate the evolutionary implications of the S-locus mutations and collect limited data on non-S-locus molecular interactions and signaling events after self- and cross-pollination of fruit tree species.

Summary Miniature inverted‐repeat transposable elements ( MITE s) are known to contribute to the evolution of plants, but only limited information is available for MITE s in the Prunus genome. We identified a MITE that has been named Falling Stones , FaSt . All structural features (349‐bp size, 82‐bp terminal inverted repeats and 9‐bp target site duplications) are consistent with this MITE being a putative member of the Mutator transposase superfamily. FaSt showed a preferential accumulation in the short AT ‐rich segments of the euchromatin region of the peach genome. DNA sequencing and pollination experiments have been performed to confirm that the nested insertion of FaSt into the S‐haplotype‐specific F‐box gene of apricot resulted in the breakdown of self‐incompatibility (SI). A bioinformatics‐based survey of the known Rosaceae and other genomes and a newly designed polymerase chain reaction ( PCR ) assay verified the Prunoideae ‐specific occurrence of FaSt elements. Phylogenetic analysis suggested a recent activity of FaSt in the Prunus genome. The occurrence of a nested insertion in the apricot genome further supports the recent activity of FaSt in response to abiotic stress conditions. This study reports on a presumably active non‐autonomous Mutator element in Prunus that exhibits a major indirect genome shaping force through inducing loss‐of‐function mutation in the SI locus.

Hungary is located halfway between Nordic Countries where forests have a dominant wood production function, and Southern European countries with an emphasised protective function of forests. When role of forests in economic development is considered, Hungary is also halfway between developing countries which rely on natural resources to a large extent, and developed countries which mostly focus on the protection and conservation of their forests. As a result of this midway position, Hungarian forest policy focuses on finding a balance between economic and protective functions of forest utilisation. However, economic role of forest is often underestimated: ordinary people or even experts emphasise the importance of environmental factors against economic issues. This general opinion indicates that direction of forest policy will turn toward a more natural management in the long run, but economic factors of forestry cannot be neglected in the forthcoming years. In private forests, conflicts between personal and public interest also have to be taken into consideration.

The majority of stone fruit species are self-incompatible, a feature that is determined by a specific recognition mechanism between the S-ribonuclease enzymes residing in the pistils and the F-box proteins expressed in the pollen tubes. Failure in the function of any component of this bipartite system resulted in self-compatibility (SC) in many cultivars of Prunus species. Peach (Prunus persica (L.) Batsch.) is the only species in the Prunoideae subfamily that is traditionally known to be self-compatible, but its molecular background is completely unknown. Isoelectric focusing and S-gene specific PCR revealed that SC is not due to functional inability of pistil ribonucleases. We hypothesize that SC may be a consequence of a kind of pollen-part mutation or the action of one or more currently unknown modifier gene(s). Only two S-alleles were identified in a set of peach genotypes of various origin and phenotypes in contrast to the 17–30 alleles described in self-incompatible fruit trees. Most important commercial cultivars carry the same S-allele and are in a homozygote state. This indicates the common origin of these cultivars and also the consequence of self-fertilization. According to the available information, this is the first report to elucidate the role of S-locus in the fertilization process of peach.