Incidence of virus infection in old vineyards of local grapevine varieties from Majorca: implications for clonal selection strategies

Abstract

Three autochthonous grapevine varieties of Majorca (Spain) were analyzed for the presence of viruses listed by the international certification programs. Enzyme-Linked Immuno-Sorbent Assay (ELISA) screenings were performed in 193 vines from 46 vineyards included in a clonal selection. Virus-free vines were only 6.4%, 9.6% and 11.5%, in Manto Negro, Callet and Moll, respectively. Infections by grapevine leafroll associated viruses (GLRaVs) were ascertained in 71%, 78% and 60% of Manto Negro, Callet and Moll vines, respectively. Each variety was also highly infected by Grapevine fanleaf virus (GFLV) and Grapevine fleck virus (GFkV). The percentage of plants displaying multiple infections was 58.4% in Manto Negro, 63.8% in Callet and 42.6% in Moll. Thus, it was very difficult to identify virusfree clones with suitable agronomic characteristics to be considered as a reference for the grape market. In order to obtain certified propagation material under such conditions of endemic viral infection, sanitation should be the main focus in clonal selection processes. However, the time and financial requirements for proper sanitation process bring to consideration the need to use, at least temporarily, standard multiplication material while certified clones are achieved.Additional key words: autochthonous varieties, grapevine certification, standard material virus incidence. Resumen Incidencia de las infecciones víricas en antiguos viñedos de tres variedades de vid autóctonas de Mallorca: consecuencias sobre las estrategias de la selección clonalEn este estudio se analizó la presencia de las virosis contempladas por las leyes internacionales en tema de certificación en tres variedades de vid autóctonas de Mallorca. Para ello se realizó el test ELISA (enzyme-linked immunosorbent assay) sobre 193 cepas procedentes de 46 viñedos incluidos en un programa de selección clonal. Las cepas que resultaron libres de los virus analizados fueron el 6,4% en Manto Negro, el 9,6% en Callet y el 11,5% en Moll. Los porcentajes de cepas infectadas por los virus asociados al síndrome del enrollado de la vid (GLRaVs) fueron 71% en Manto Negro, 78% en Callet y 60% en Moll. Se detectaron también altas tasas de infecciones para el virus del entrenudo corto infeccioso de la vid (GFLV) y el virus del jaspeado de la vid (GFkV) en las tres variedades. Los porcentajes de cepas sujetas a infecciones múltiples fueron 58,4% en Manto Negro, 63,8% en Callet y 42,6% en Moll. Por tanto fue difícil encontrar cepas que cumpliesen tanto los requisitos sanitarios para la certificación como aquellos agronómicos necesarios según las exigencias del mercado vitivinícola. En tales condiciones de infecciones víricas endémicas, el saneamiento debería ser el primer objetivo a seguir con el fin de obtener material de propagación certificado. Sin embargo, el tiempo y los recursos económicos necesarios para llevar a cabo el proceso de saneamiento conllevan la necesidad de considerar el uso temporal de material de propagación estándar hasta que se obtengan clones cer...

Virus interference on local scale viticulture: the case of Moll variety from Majorca (Spain)

“…Instead, the requirements for candidate clone choice based on Sugar Content and Titratable Acidity levels in berries (Cretazzo et al, 2010b). Thus, Yield, Sugar Content and Titratable Acidity were selected as the most representative vine parameters to perform the following analyses.…”

“…with commonly East -West row orientation. More details about the clonal selection process in Majorca and the criterion for vine choice are described by Cretazzo et al (2010b).…”

“…These are the only viruses listed by legislation for grapevine certification and the most economically immost economically important in Majorca (Cretazzo et al, 2010a). In order to confirm results, for both negative and doubtful samples, the tests were replicated in the same year and, if necessary, repeated and replicated in 2006 (see Cretazzo et al 2010b). The tests were performed on 76 vines located in 12 vineyards.…”

“…In the last decade, in Spain, monovarietal wines obtained with local varieties started to have a great promotion among growers, especially in the case of whites (Campo et al, 2008). In Majorca (39°N; 1°E), Moll is the most important and cultivated white variety and its contribution to typical wine aroma is essential (Cretazzo et al, 2010b). The ascent of Moll occurred in the last 20 years.…”

“…In spite of that, until the beginnings of clonal selection in 2000, no rigorous scientific approach was undertaken in order to study this variety. Clonal selection is the main method to improve a wine grapevine (Vitis vinifera L.) variety (see Cretazzo et al, 2010b). Its main aim is to identify and propagate clones free of viruses that are listed in recognised certification programs.…”