Prevalence, polyphasic identification, and molecular phylogeny of dagger and needle nematodes infesting vineyards in southern Spain

Abstract

The occurrence and geographic distribution of longidorid nematode species inhabiting the rhizosphere of grapevine plants in southern Spain were investigated. Nematode surveys were conducted on 77 vineyards during the spring seasons of 2006, 2007 and 2008 in the main Andalusian grapevine-growing areas, including the provinces of Cádiz, Córdoba, and Huelva. Morphological and morphometrical studies identified two Longidorus and nine Xiphinema species, viz.: Longidorus alvegus, L. magnus, Xiphinema adenohystherum, X. hispidum, X. index, X. italiae, X. lupini, X. nuragicum, X. pachtaicum, X. rivesi, and X. turcicum. Overall, frequencies of infestation were, in decreasing order: X. pachtaicum 90.8%, X. index 30.3%, X. italiae 13.2%, L. magnus 11.8%, X. hispidum 7.9%, X. lupini 3.9%, L. alvegus and X. rivesi 2.6%, and X. adenohystherum, X. nuragicum and X. turcicum 1.3%. Xiphinema hispidum, X. lupini, L. alvegus and L. magnus were compared with nematode type specimens and are reported for the first time in Spain. Furthermore, the male of L. alvegus is described for the first time in the literature. Molecular characterisation of these species using D2-D3 expansion regions of 28S rRNA, 18S rRNA and ITS1-rRNA was carried out and maximum likelihood and Bayesian inference analysis were used to reconstruct phylogenetic relationships among these species and with other longidorids. The monophily of the genera Xiphinema and Longidorus was accepted and the genera Paralongidorus and Xiphidorus were rejected by the ShimodairaHasegawa test based on tree topologies.

An update on the genus Longidorus, Paralongidorus and Xiphinema (Family Longidoridae) in Portugal

“…lupini Roca &Pereira, 1993 are two Iberian endemic morphospecies in group 5, phylogenetically and morphologically related to the putative virus vector X. italiae (morphospecies group 7) (Gutiérrez-Gutiérrez et al 2011). They were described originally from the localities of Palmela (province of Estremadura) and Coruche (province of Ribatejo) (Figure 2; Table S1) and have later been reported extensively from cultivated and natural environments of the Southern Iberian Peninsula (Peña-Santiago et al 2006;Gutiérrez-Gutiérrez et al 2011, 2013b. The putative GFLV vector nematode X. italiae, one of the most widespread Xiphinema species in the Mediterranean area where it has been associated with many plant species (Brown & Taylor 1987;Taylor & Brown 1997;Coomans et al 2001;Decraemer & Chaves 2012), was reported for the first time in the locality of Alpiarça (province of Ribatejo) (Lima 1974) and later found infesting several commercial vineyards in sandy soils in Estremadura, Ribatejo and Douro wine regions (Lima 1974;Bravo & Lemos 1997;Taylor & Brown 1997;Gutiérrez-Gutiérrez et al 2015) (Figure 2; Table S1).…”

“…Xiphinema rivesi Dalmasso, 1969, and X. santos Lamberti, Lemos, Agostinelli & D'Addabbo, 1993 have been reported in Portugal (Lamberti et al , 1994Bravo & Lemos 1997) (Figures 1, 4, 5; Table S1) and other Mediterranean regions (Lamberti et al 1996(Lamberti et al , 2000Taylor & Brown 1997;Decraemer & Chaves 2012); however, only the first species is widespread (Lamberti et al 2000Coomans et al 2001;Decraemer & Robbins 2007). Both species belong to the X. americanumsubgroup and appear to be morphologically almost identical, but the Iberian populations of both species are clearly separated phylogenetically using molecular ribosomal markers (Gutiérrez-Gutiérrez et al 2011;Archidona-Yuste et al 2016a). Xiphinema rivesi is a vector of several important nepovirus (Taylor & Brown 1997;Decraemer & Chaves 2012) but in Portugal its presence has never been associated with viral diseases in plants.…”

“…Later, two morphologically near identical species were described from Portugal: L. alvegus Roca, Pereira & Lamberti, 1989and L. reisi Roca & Bravo, 1993(Roca et al 1989bRoca & Bravo 1993). These two Longidorus species are considered Iberian endemics (Figure 3; Table S1) but only L. alvegus has been reported for Spain (Brown & Taylor 1987;Navas et al 1990;Gutiérrez-Gutiérrez et al 2011;Archidona-Yuste et al 2016b). Roca & Bravo (1996) described a new species named Longidorus crataegi Roca & Bravo, 1996, from several populations found in the rhizosphere of Crataegus oxycantha L. in the southwest region of Portugal (Brown & Lemos 1997) (Figure 3; Table S1), and subsequently this species has also been reported from a several Spanish localities (Gutiérrez-Gutiérrez et al 2012b;Archidona-Yuste et al 2016b).…”

“…In general, the biodiversity of plant nematodes of Longidoridae in the Iberian Peninsula appears to be one of the highest in the world (Taylor & Brown 1997;Coomans et al 2001;Peña-Santiago et al 2006;Archidona-Yuste et al 2016a, b), although it appears to be higher in Xiphineminae than in Longidorinae (Bravo & Lemos 1997;Peña-Santiago et al 2006). Many of them are considered as to be species endemic to the Iberian Peninsula (Table S1) and Gutiérrez-Gutiérrez et al (2011) hypothesized that the Iberian Peninsula could be considered as a possible centre of origin for some Xiphinema species because of the high number of endemic species and their phylogenetic grouping.…”

Morphological characterisation and diagnostics of Xiphinema non-americanum group species (Nematoda: Longidoridae) from Romania using mutiplex PCR

“…0.5 % dissimilarity) in D2-D3 sequences between the two Romanian populations were detected and one to three (or less than 0.3% divergence) with the corresponding sequences of X. vuittenezi from Hungary (AY601614) and Czech Republic (EF614266) deposited in GenBank (He et al 2005;. Similar low level of interpopulation genetic diversity (<1.5 %) was revealed for other Xiphinema nonamericanum group species such as X. index (0 -0.3 %), X. diversicaudatum (0 -0.8 % and X. italiae (0.3 -1.4 % GenBank accession numbers AY601613, FJ713153, HM921350, HM921351) (He et al, 2005;Gutiérrez-Gutiérrez et al, 2011;Kumari & Di Cesare, 2013). The ITS-RFLP analysis for both populations produced identical species-specific patterns that clearly identified X. vuittenezi from Romania (Fig.…”