First report of Meloidogyne naasi parasitizing turfgrass in Portugal

Cordeiro

et al. 2021

Plants

Potato is the third most important crop in the world after rice and wheat, with a great social and economic importance in Portugal as it is grown throughout the country, including the archipelagos of Madeira and the Azores. The tropical root-knot nematode (RKN) Meloidogyne luci is a polyphagous species with many of its host plants having economic importance and the ability to survive in temperate regions, which pose a risk to agricultural production. In 2019, M. luci was detected from soil samples collected from the council of Santo António in Pico Island (Azores). Bioassays were carried out to obtain females, egg masses, and second-stage juveniles to characterize this isolate morphologically, biochemically, and molecularly. The observed morphological features and morphometrics showed high similarity and consistency with previous descriptions. Concerning the biochemical characterization, the esterase (EST) phenotype displayed a pattern with three bands similar to the one previously described for M. luci and distinct from M. ethiopica. Regarding the molecular analysis, an 1800 bp region of the mitochondrial DNA between cytochrome oxidase subunit II (COII) and 16S rRNA genes was analyzed and the phylogenetic tree revealed that the isolate grouped with M. luci isolates (99.17%). This is the first report of M. luci parasitizing potato in the Azores islands, contributing additional information on the distribution of this plant-parasitic nematode.

Section: Biochemical Characterizationmentioning

confidence: 99%

“…Plants 2021, 10, 99 2 of 8 RKN are one of the oldest known parasitic nematodes of plants and considered serious pests of economically important crops [4,5]. The genus comprises more than 90 species [6] [7][8][9][10][11].…”

Section: Introductionmentioning

confidence: 99%

First Detection of Meloidogyne luci (Nematoda: Meloidogynidae) Parasitizing Potato in the Azores, Portugal

Cordeiro

et al. 2021

Plants

“…Currently, the biochemical electrophoretic analysis of nonspecific esterases (EST) is a widely used method employed to differentiate Meloidogyne species, with many species-specific isozyme patterns already published. In Portugal, many species have been reported: Meloidogyne arenaria; M. chitwoodi Golden et al [8][9][10][11][12][13][14]. Due to the risk that various Meloidogyne species pose to agricultural production, a national field survey programme that includes the islands of Azores and Madeira was established in 2019 and led to the detection of M. luci associated with potato in the island of Pico, Azores [14].…”

Section: Introductionmentioning

confidence: 99%

Root-Knot Nematode Species Associated with Horticultural Crops in the Island of Azores, Portugal

Cordeiro³

et al. 2022

Horticulturae

Plant-parasitic nematodes (PPN) are an economically important group of plant pests present throughout the world. In particular, root-knot nematodes (RKN), sedentary endoparasites of a wide variety of economically important hosts with the ability to survive in temperate regions. During 2020–2021 an extensive survey of Meloidogyne spp. was undertaken on the island of São Miguel Azores, Portugal. A total of 80 samples comprising 23 species of plants were collected from 13 localities in 4 districts of the island. Samples included field and greenhouse vegetable crops. Bioassays were carried out to obtain females and juveniles for morphological and biochemical characterization of the isolates. The observed morphological features showed high similarity and consistency with previous descriptions of the genus. Concerning the biochemical characterization, the esterase (EST) phenotype displayed the patterns described for M. incognita, M. arenaria, and M. javanica. Meloidogyne incognita was found to be the most prevalent species with respect to both natural host range and geographical distribution, followed by M. arenaria and M. javanica. This is the first field survey that assesses the species of root-knot nematodes associated with horticultural crops in the Azores Island, contributing additional information on the distribution of this genus.

“…Root-knot nematodes (RKNs) are one of the oldest known parasitic nematodes of plants and considered serious pests of economically important crops [ 5 ]. The genus comprises more than 100 species, with many of them reported in Portugal: Meloidogyne arenaria (Neal, 1889) Chitwood, 1949; Meloidogyne chitwoodi Golden et al, 1980; Meloidogyne enterolobii Yang and Eisenback, 1983; Meloidogyne hapla Chitwood, 1949; Meloidogyne hispanica Hirschmann, 1986; Meloidogyne incognita (Kofoid and White, 1919) Chitwood, 1949; Meloidogyne javanica (Trub, 1885) Chitwood, 1949; Meloidogyne luci Carneiro et al, 2014; Meloidogyne lusitanica Abrantes and Santos, 1991; and Meloidogyne naasi Franklin, 1965 [ 6 , 7 , 8 , 9 , 10 , 11 , 12 ]. The species, M. arenaria , M. hapla , M. incognita and M. javanica , are regarded as the most important, due to their worldwide distribution and polyphagia [ 2 , 4 ].…”

Section: Introductionmentioning

confidence: 99%

The Northern Root-Knot Nematode Meloidogyne hapla: New Host Records in Portugal

Serra³

et al. 2022

Biology

Root-knot nematodes (RKNs), Meloidogyne spp., are a group of plant-parasitic nematodes (PPNs) of great economic significance worldwide. The northern root-knot nematode, Meloidogyne hapla, is one of the most important species of RKNs occurring in cold regions. In Portugal so far, M. hapla has been found parasitizing potato and fig trees. During surveys carried out in 2019–2022 in fields for horticultural and ornamental production, soil and root samples were collected. Roots were observed under a stereomicroscope to determine the presence of galls. Nematodes were extracted from the soil. Morphological features showed a high similarity and consistency with previous descriptions of the genus. For molecular analysis, total genomic DNA was isolated from single nematodes and used to amplify in multiplex reaction using the species-specific primers JMV1, JMV2 and JMVhapla, and for sequencing of the ITS region with the primers TW81/AB28. Multiplex PCR amplification produced a specific fragment of 440 bp and PCR amplification of the ITS region yielded a single fragment of 550 bp, as expected. The obtained sequences showed a similarity ranging from 99.8% to 100% with the sequences of M. hapla available in the database. The phylogenetic tree revealed that the isolates grouped with M. hapla isolates. From the 690 samples collected, M. hapla was detected in three different hosts (grapevine, eucalyptus and potato) in four districts of mainland Portugal and on Madeira Island. To our knowledge, this is the first report of M. hapla infecting the grapevine and eucalyptus in Portugal.