Root-knot nematodes from the genus
are polyphagous plant endoparasites and agricultural pests of global importance. Here, we report the high-quality genome sequence of
population SI-Smartno V13. The ...resulting genome assembly of
SI-Smartno V13 consists of 327 contigs, with an N50 contig length of 1,711,905 bp and a total assembly length of 209.16 Mb.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Root-knot nematodes (Meloidogyne spp.) are considered the most aggressive, damaging, and economically important group of plant-parasitic nematodes and represent a significant limiting factor for ...potato (Solanum tuberosum) production and tuber quality. Meloidogyne luci has previously been shown to be a potato pest having significant reproductive potential on the potato. In this study we showed that M. luci may develop a latent infestation without visible symptoms on the tubers. This latent infestation may pose a high risk for uncontrolled spread of the pest, especially via seed potato. We developed efficient detection methods to prevent uncontrolled spread of M. luci via infested potato tubers. Using hyperspectral imaging and a molecular approach to detection of nematode DNA with real-time PCR, it was possible to detect M. luci in both heavily infested potato tubers and tubers without visible symptoms. Detection of infested tubers with hyperspectral imaging achieved a 100% success rate, regardless of tuber preparation. The real-time PCR approach detected M. luci with high sensitivity.
The root-knot nematode
Meloidogyne luci
generates serious damages on economically important crops. However, the knowledge on host status of cultivated plants to this nematode species is highly ...limited. In this study, 71 cultivars of 43 plant species and varieties from Alliaceae, Apiaceae, Asteraceae, Brassicaceae, Chenopodiaceae, Compositae, Cucurbitaceae, Fabaceae, Malvaceae, Poaceae, Rosaceae and Solanaceae families were screened for their host status to an isolate of
M. luci
in pot assays under controlled greenhouse conditions. Host status of plant cultivars was determined based on nematode reproduction factor. Of the tested cultivars, five cultivars were identified as non-hosts (Rf = 0), 20 cultivars as poor hosts (0 < Rf < 1), 25 cultivars as good hosts (1 ≤ Rf < 10) and 21 cultivars as excellent hosts (Rf ≥ 10). Strawberry cv. Sweet Ann, cotton cv. SC 2079, garlic cv. Taşköprü, soybean cv. Arısoy and oat cv. Even were classified as non-hosts. Although carrot cv. Nantes Scarlet, melon cv. Ananas, leek cv. Bt Hotanlı 016 and onion cv. Bt Depocu were considered as poor hosts, no nematode reproduction was detected on some replicates of these cultivars. Furthermore, the response of 15 cultivars selected from non-hosts or poor hosts to
Mi
-virulent isolate of
M. luci
was also evaluated
.
Of non-host cultivars tested, garlic and strawberry did not allow nematode reproduction while soybean cv. Arısoy provided a good host (Rf = 4.13) for
Mi
-virulent isolate of
M. luci
. The poor-host status of 9 cultivars, representing arugula, broccoli, carrot, kale, maize, melon and watermelon, did not change with the tested isolates of
M. luci
(0.01 ≤ Rf ≤ 0.58). Non-host to poor host cultivars to both isolates of
M. luci
have potential for nematode suppression in crop rotations.
Meloidogyne luci is a polyphagous plant parasitic nematode species with a potential to cause great losses in agricultural production. M. luci can parasitize over thirty important crop species as well ...as ornamentals, herbs and weeds. In this report we documented a weed plant common groundsel (Senecio vulgaris L.) as a new naturally-infected host species which could act as a reservoir for this pest.
Root-knot nematodes (RKN) of the tropical group reproducing as a rule with mitotic parthenogenesis are highly polyphagous and damaging pests causing great losses in crop production. Morphometrical ...and molecular characters of three closely related tropical RKN species have been analysed in order to identify species-specific diagnostic parameters and examine the relationship between species. Morphometrical characters of
M. ethiopica, M. luci
and
M. inornata
isolates were similar and overlapped when compared between species and isolates of the same species indicating a very close relationship between the three species. Additionally, structure of
map-
1 genes was analysed, which provided the evidence of identical structure of
map-
1 family genes in
M. ethiopica
,
M. inornata
and
M. luci.
The unique structure of
map-
1 genes when compared to the other tropical RKN species further supports close relationship of the three species and therefore we have classified them together as
M. ethiopica
group. In addition, our results showed that the emergence of a virulent
M. luci
population does not correlate with the loss of
map
-1 genes as it was previously indicated for
M. incognita
(Castagnone-Sereno et al.
2009
). Further, we have developed novel molecular methods to aid in identification of these nematodes: a PCR based method with primers specific for the
M. ethiopica
group comprising
M. ethiopica M. luci
and
M. inornata
, and a PCR based method with primers specific for the tropical RKN group species. Our results show that species of
Meloidogyne ethiopica
group share high similarity at morphological and genetic level.
The root knot nematode (RKN)
Meloidogyne luci
, recently added to the European Plant Protection Organization Alert List, represents a potential threat to the production of important solanaceous ...crops. RKN resistance in tomato (
Solanum lycopersicum
L.) is conferred by a single dominant gene. The objectives were to screen the RKN resistance
Mi-1.2
gene in 27 tomato hybrids and cultivars and assess the ability of
M. luci
and
M. ethiopica
to reproduce on these accessions. Thirteen Mimi tomato genotypes, two MiMi and twelve lacking the
Mi-1.2
gene (mimi) were identified. Tomato accessions Reconquista (MiMi) and Vimeiro F1, Paipai, Sahel, Agora F1, Amaral, Valoasis RZ F1 and SV1917 (Mimi) displayed a resistant reaction to both RKN species with a reproduction factor (Rf) ranging from 0.00 to 0.14. Significant differences in
M. luci
and
M. ethiopica
reproduction were detected among and within the
Mi-1.2
allelic conditions, which may reflect a dosage effect of the gene as well as an influence of the plant’s genetic background, respectively. Results revealed that resistant tomato accessions carrying the resistant
Mi
gene have potential to be employed as an alternative to the use of nematicides aiming to control
M. luci
, and
M. ethiopica
and the most common RKN species.
Meloidogyne chitwoodi, M. enterolobii, and M. luci are present in some EU countries, with restricted distributions, and plant resistance can be used to manage these nematodes. Two pot experiments ...were conducted under controlled conditions for 56 d to assess the host suitability of two potential rootstocks, Cucumis metuliferus BGV11135 and Citrullus amarus BGV5167, to one isolate of each nematode. The susceptible cucumber (Cucumis sativus) ‘Dasher II’, watermelon (Citrullus lanatus) ‘Sugar Baby’ and tomato (Solanum lycopersicum) ‘Coração-de-Boi’ were included for comparisons. A histopathological study using confocal-laser microscopy was also conducted 15 d after nematode inoculations. In the pot test, the rootstocks showed lower numbers of galls, egg masses, and eggs per plant than their susceptible ones. Reproduction indices of the rootstocks varied from immune to moderately resistant, depending on the isolate-rootstock combination. In the histopathological study, M. enterolobii and M. luci induced similar numbers of giant cells (GC) per feeding site in all germplasms. However, GC volumes and numbers of nuclei in rootstocks were lower than in the susceptible germplasms. GCs induced by M. chitwoodi were only detected in susceptible cucumber. These results emphasize the potential of C. metuliferus and C. amarus as effective, eco-friendly strategies for managing root-knot nematodes, and show the complex these host-pathogen interactions.
Many root‐knot nematode (RKN) species (Meloidogyne spp.) are polyphagous and cultivated tomato (Solanum lycopersicum) is one of their preferential hosts, leading to significant losses. It is known ...that the dominant Mi‐1.2 gene in tomato confers resistance to the three most important RKN species—M. incognita, M. javanica, and M. arenaria, and minor species—M. ethiopica, M. hispanica, and M. luci. However, little information is available about resistance of tomatoes carrying this gene to other tomato‐infecting RKN species. In this study, resistance conferred by the Mi‐1.2 gene/locus was evaluated against populations of 15 Meloidogyne species, employing tomato cultivars Santa Clara (homozygous recessive mi‐1.2/mi‐1.2, susceptible) and Debora Plus (heterozygous Mi‐1.2/mi‐1.2, resistant). Debora Plus was susceptible only to M. enterolobii and M. hapla, and was resistant to the other Brazilian populations of M. arenaria, M. ethiopica, M. exigua, M. hispanica, M. incognita, M. inornata, M. izalcoensis M. javanica, M. konaensis, M. luci, M. morocciensis, M. paranaensis, and M. petuniae. Mi‐1.2 is located on tomato chromosome 6 within a cluster of seven homologous genes of the nucleotide‐binding site leucine‐rich repeat (NBS‐LRR) family; further research is required to confirm if this multiple Meloidogyne spp. resistance phenotype is controlled exclusively by Mi‐1.2 or by combined action of other closely linked genes. This evaluation of resistance of the Debora Plus cultivar to several Meloidogyne species suggests that the Mi‐1.2 gene/locus may reduce losses induced by a wide range of Meloidogyne spp. Further studies using additional resistant cultivars and other populations of Meloidogyne spp. are needed to confirm these results.
Tomato cv. Debora Plus (with Mi1.2) has resistance to Meloidogyne arenaria, M. ethiopica, M. exigua, M. hispanica, M. incognita, M. inornata, M. izalcoensis, M. javanica, M. konaensis, M. luci, M. morocciensis, M. paranaensis, and M. petuniae.
Meloidogyne luci has been identified in various countries around the world parasitizing economically important crops and, due to its potential to cause serious damage to agriculture, was included in ...the European and Mediterranean Plant Protection Organization Alert List in 2017. This species shares morphological and molecular similarities with M. ethiopica and M. inornata, and a M. ethiopica group was therefore established. Although specific primers for the DNA amplification of species belonging to the M. ethiopica group have been developed previously, the primers were not species-specific, so molecular markers for the specific detection of M. luci are still needed. The objective of this study was to develop a SCAR marker for the detection of M. luci and the discrimination from other Meloidogyne spp. based on the intraspecific variability found in RAPD markers. RAPD screening of M. luci and M. ethiopica genome was used for the identification of a specific amplification product on M. luci, which was cloned, sequenced and converted into a SCAR marker. The specificity of the designed primers (Mlf/r) was tested and produced a fragment (771 bp) for all nine M. luci isolates with no amplification for the other nine Meloidogyne spp., including M. ethiopica and M. inornata. Additionally, the proper amplification of the M. luci SCAR-marker was also successful with DNA from galls of M. luci infected tomato roots. The results obtained in this study reveal that the specific molecular detection of M. luci was achieved and that the developed methodology can be used for routine diagnosis purposes, which are essential to monitoring the distribution and spread of M. luci in order to implement future effective and integrated nematode pest management programs.
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)
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,
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
and distinct from
. 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
isolates (99.17%). This is the first report of
parasitizing potato in the Azores islands, contributing additional information on the distribution of this plant-parasitic nematode.