No abstract

a b s t r a c tThe genetic heritage of the Asturian grapevine (Vitis vinifera L.) has been declining over the past century due to the phylloxera attack and the further abandonment of this culture. In addition, efforts in recent years to restore the Asturian vineyard with the pulling-up of old vineyards and replanting with cultivars endorsed by Cangas Quality Wine regulations are contributing even more to this genetic erosion. The aim of this study was the evaluation and identification of the phytogenetic resources of the Asturian grapevine. A total of 293 accessions were collected in old vineyards and analyzed through nine microsatellite markers. Forty-two different genotypes were obtained, including six profiles with allelic variations. Only 27 cultivars were identified when compared with national and international databases; some of them had not been found in this region before. Homonymies and synonymies have also been detected. These results provide an overview of the status of current grapevine phytogenetic resources in Asturias. Despite the substantial genetic erosion that the Asturian vineyard has suffered, a higher variability than expected has been detected. The finding of new grapevine genotypes is a fact of great importance. The genetic grapevine resources are being drastically reduced all over the world, so this new genetic material has to be included in germplasm banks for its conservation and further agronomical and enological evaluation.

`Albariño' (Vitis vinifera L.) is an important grape cultivar in Spain, morphologically diverse but subject to much misnaming. The objectives of the present work were to correct some of the more common misnamings concerning `Albariño' and to evaluate the genetic variability within this cultivar by analyzing DNA polymorphisms using randomly amplified polymorphic DNA (RAPD) markers and microsatellite techniques. Several accessions of `Albariño' (16 accessions from Misión Biológica de Galicia, one accession from El Encin, one accession from Rancho de la Merced), related cultivars (`Alvarinho', `Caíño blanco', `Cainho branco', `Loureiro'), and cultivars presumably identical to misnomers (`Savagnin blanc' and `Gewürztraminer') were analyzed using 20 RAPD markers and six microsatellite loci. Both techniques revealed polymorphism among `Albariño', `Caíño blanco', `Albariño' from Rancho de la Merced and `Loureiro'. No polymorphism was detected among the 16 `Albariño' accessions from Galicia, the `Albariño' accession from El Encin and `Alvarinho', nor among the `Albariño' accession from Rancho de la Merced, `Savagnin blanc' and `Gewürztraminer', nor between `Caíño blanco' and `Cainho branco'. These results enabled us to clarify the main misnomers concerning these cultivars. The absence of polymorphism among the true `Albariño' accessions did not allow the detection of any clonal variation. The suitability of both techniques for defining the cultivar level for grapevine is discussed.

Dark discolorations of the vascular vessels of 3-year-old potted plants of Asturian grapevine cultivar (Northern Spain), were observed during pruning. These symptoms can be associated to fungal trunk diseases that, in the last decades, are affecting young vineyards all over the world. Cross sections from root, trunk and canes of 19 young grapevine plants were analyzed for the presence of pathogenic fungi associated with these diseases. Non-pathogenic fungi were isolated from both asymptomatic and symptomatic samples, showing that dark discolorations, in some cases, were a consequence of abiotic causes. Regarding pathogenic fungi, Cylindrocarpon spp. colonies were the most frequent, isolated mainly from roots and from asymptomatic tissue. Botryosphaeria spp. colonies were mostly isolated from trunk and from sections with dark discolorations generated by pruning. Phaeoacremonium spp. was isolated from all the organs (roots, trunk and canes). Only one colony of Libertella spp. was isolated. These results suggest the need of a standard protocol, combining treatments and management activities, to be performed in nurseries to limit the spread of these diseases.    

SUMMARYThe abandonment of Asturian vineyards over the last century almost resulted in the extinction of the grapevine crop and major cultivar confusion. Due to the restoration of a number of these vineyards in recent years, research into the regional varietal stock is needed. The aims of the present study were to characterise genetic resources of Vitis vinifera L. in Asturias and to identify synonyms and homonyms through an analysis of six microsatellite markers: VVS2, VVMD5, VVMD7, VVMD27, VrZAG62, and VrZAG79. These markers are used internationally as recommended descriptors for the identification of grapevine cultivars and allow comparisons between laboratories. After PCR amplification of these microsatellite sequences, they were analysed by capillary electrophoresis. Forty-six accessions of V. vinifera L., corresponding to 14 cultivars, were analysed, but only nine different genotype profiles were found, due to synonyms for 'Albarín Tinto', 'Albarín Blanco' and 'Verdejo Tinto', and two homonyms for 'Albarín Blanco' being identified ('Godello' and 'Savagnin Blanc'). The most informative locus was VVMD5 and the least informative was VVMD27. The heterozygosity observed at all loci was higher than expected.