02227nas a2200169 4500008004100000245014200041210006900183260001600252300001400268490000700282520165200289100001601941700001701957700002101974700001901995856004302014 2017 eng d00aMetabarcoding and development of new Real-time specific assays reveal Phytophthora species diversity in Holm Oak forests in eastern Spain0 aMetabarcoding and development of new Realtime specific assays re cJan-04-2016 a115–1230 v663 a

The evergreen holm oaks (Quercus ilex subsp. ilex and Q. ilex subsp. ballota) are the most representative tree species in the Iberian peninsula and the main tree species in oak-rangeland ecosystems (dehesas). Oak decline in western, central and southern parts of Spain has been associated with root rot caused by Phytophthora cinnamomi for decades. However, Phytophthora species such as P.  quercina and P. psychrophila have recently been found associated with Quercus decline in eastern Spain where calcareous soils are predominant. Soil and root samples from two Quercus forests presenting decline symptoms in two different geographical areas in eastern Spain (Carrascar de la Font Roja and Vallivana) were analysed by amplicon pyrosequencing. Metabarcoding analysis showed Phytophthora species diversity, and revealed that an uncultured Phytophthora taxon, named provisionally Phytophthora taxon ballota, was the predominant species in both areas. In addition, a real-time PCR assay, based on the pyrosequencing results, was developed for the detection of this uncultured Phytophthora taxon, and also for the detection of P. quercina. TaqMan assays were tested on soil and root samples, and on Phytophthora pure cultures. The new assays showed high specificity and were consistent with metabarcoding results. A new real-time PCR protocol is proposed to evaluate the implication of different Phytophthora spp. in oak decline in eastern Spain.

1 aCatalà, S.1 aBerbegal, M.1 aPérez-Sierra, A1 aAbad-Campos, P uhttp://doi.wiley.com/10.1111/ppa.12541