In the Mediterranean area, the production of persimmon (Diospyros kaki Thumb) [2n =6x =90] has increased recently as an alternative to the major fruit crops. In Spain, production relies almost exclusively on the cultivar "Rojo Brillante" which accounts for 83% of the crop. A crop based on a monovarietal culture implies several commercial risks that can compromise the future of the crop. Although the species was introduced in Europe very recently, it is well adapted to the climate of southern Europe. However, the recent introduction from Japan, the mistakes on the identity of varieties in the collections due to a bad translation of variety names from Japanese, and the lack of genetic characterization of many varieties have caused difficulties for effective management of the available genetic resources. The present paper was aimed at exploring the genetic diversity among different persimmon cultivars, including those collected in the European survey as well as Japanese cultivars. Seventy-one persimmon cultivars coming from two European collections that included accessions from Japan, Italy, and Spain were analyzed using 19 polymorphic microsatellite markers. A total of 206 alleles were obtained, with a mean value of 10.8 alleles per locus. A neighbor joining dendrogram and a principal coordinate analysis arranged the cultivars according to their genetic relationships. Analysis of molecular variance revealed significant genetic variability between and within groups, 73.3% and 85.2% for astringent-type and country origin, respectively. The simple sequence repeat markers classified the persimmon cultivars according to their genetic relationship.

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MBW protein complexes containing MYB, bHLH and WD40 repeat factors are known transcriptional regulators of secondary metabolites production such as proanthocyanidins and anthocyanins, and developmental processes such as trichome formation in many plant species. DkMYB2 and DkMYB4 (MYB-type), DkMYC1 (bHLH-type) and DkWDR1 (WD40-type) factors have been proposed by different authors to take part of persimmon MBW complexes for proanthocyanidin accumulation in immature fruit, leading to its characteristic astringent flavour with important agronomical and ecological effects. We have confirmed the nuclear localization of these proteins and their mutual physical interaction by bimolecular fluorescence complementation analysis. In addition, transient expression of DkMYB2, DkMYB4 and DkMYC1 cooperatively increase the expression of a persimmon anthocyanidin reductase gene (ANR), involved in the biosynthesis of cis-flavan-3-ols, the structural units of proanthocyanidin compounds. collectively, these data support the presence of MBW complexes in persimmon fruit and suggest their coordinated participation in ANR regulation for proanthocyanidin production.

Successful haploid induction in loquat (Eriobotrya japonica (Thunb.) Lindl.) through in situ-induced parthenogenesis with gamma-ray irradiated pollen has been achieved. Female flowers of cultivar ‘Algerie’ were pollinated using pollen of cultivars ‘Changhong-3’, ‘Cox’ and ‘Saval Brasil’ irradiated with two doses of gamma rays, 150 and 300 Gy. The fruits were harvested 90, 105 and 120 days after pollination (dap). Four haploid plants were obtained from ‘Algerie’ pollinated with 300-Gy-treated pollen of ‘Saval Brasil’ from fruits harvested 105 dap. Haploidy was confirmed by flow cytometry and chromosome count. The haploids showed a very weak development compared to the diploid plants. This result suggests that irradiated pollen can be used to obtain parthenogenetic haploids.

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