No abstract

Using micropropagation through tissue culture has become the most used approach worldwide for mass production for the conservation of endangered species. However, the screening of somaclonal variations generated using in vitro culture is usually restricted to the first generation of micropropagated plants, when they have not yet been released in the field. Accordingly, the fate of genetically modified regenerants after sexual reproduction is usually not assessed and changes in the genetic structures of species are unknown. In this work, we assess the cytogenetic stability of two rDNA gene families in the offspring of experimental crosses between accessions generated after in vitro culture and wild individuals of Cistus heterophyllus (Cistaceae). The cytogenetic rDNA profiles (45S rDNA, 5S rDNA) of 118 accessions including wild and in vitro micropropagated individuals and bi-directional artificial crosses between wild and in vitro-generated plants were assessed by fluorescence in situ hybridization (FISH) and Ag-NOR staining. Plants regenerated by micropropagation showed a lower size of the FISH signals in a 45S rDNA site, but this condition was not present in the wild accessions. Three new cytogenetic and cytological variants were present in 36% of the experimental progeny, involving the amplification of one additional 45S rDNA site and the presence of heteromorphic nucleoli. rDNA-based genomic instability was present after sexual reproduction between wild and in vitro-generated plants. The results of this study discourage the use of micropropagated materials for plant conservation unless comprehensive surveys of the genetic integrity and stability of the regenerants are performed after crossing between wild and micropropagated plants.

The inventory of the taxa collected during the annual field trip of the working group for Floristics Systematics and Evolution of the Italian Botanical Society is reported. It was held in 2013 along the Maddalena Mountains a mountain ridge of the southern Apennines located between the Basilicata and Campania administrative regions (southern Italy) considered as being poorly characterized in terms of vascular flora. A total of 701 units belonging to 74 plant families were recorded including two varieties and four hybrids.Thirty-five taxa resulted endemic to Italy and only 11 alien species were detected while 36 taxa are new or confirmed for the regional floras of Basilicata and/or Campania. In particular 12 taxa are new for Basilicata while four are confirmed. Regarding Campania 14 taxa resulted new for the regional flora and five were confirmed.

The inventory of the taxa collected during the annual field trip of the working group for Floristics, Systematics and Evolution of the Italian Botanical Society is reported. It was held in 2013 along the Maddalena Mountains, a mountain ridge of the southern Apennines located between the Basilicata and Campania administrative regions (southern Italy), considered as being poorly characterized in terms of vascular flora. A total of 701 units belonging to 74 plant families were recorded including two varieties and four hybrids.