Diagnostic methods for identification of root-knot nematodes species from Brazil

ABSTRACT: The accurate identification of root-knot nematode (RKN) species (Meloidogyne spp.) is essential for implementing management strategies. Methods based on the morphology of adults, isozymes phenotypes and DNA analysis can be used for the diagnosis of RKN. Traditionally, RKN species are identified by the analysis of the perineal patterns and esterase phenotypes. For both procedures, mature females are required. Over the last few decades, accurate and rapid molecular techniques have been validated for RKN diagnosis, including eggs, juveniles and adults as DNA sources. Here, we emphasized the methods used for diagnosis of RKN, including emerging molecular techniques, focusing on the major species reported in Brazil.

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Root-knot nematodes (Meloidogyne spp.) in Europe

Nematology ◽

10.1163/138855410x526831 ◽

2011 ◽

Vol 13 (1) ◽

pp. 3-16 ◽

Cited By ~ 115

Author(s):

Wim Wesemael ◽

Nicole Viaene ◽

Maurice Moens

Keyword(s):

Management Strategies ◽

Resistance Breeding ◽

Common Species ◽

Molecular Techniques ◽

Morphological Identification ◽

Meloidogyne Hapla ◽

Root Knot Nematodes ◽

Important Species ◽

Meloidogyne Spp ◽

Meloidogyne Species

AbstractIn Europe, root-knot nematodes are increasingly important. Out of more than 90 Meloidogyne species currently described, 23 have been found on the continent. In the cooler climates, Meloidogyne hapla, M. naasi, M. chitwoodi and M. fallax are prevalent. Meloidogyne arenaria, M. javanica and M. incognita are the most common species in warmer conditions of southern Europe, but also in glasshouses in northern Europe. Morphological identification of root-knot nematodes is difficult and time consuming; therefore, many research groups have been developing molecular techniques for identification of Meloidogyne species. Meloidogyne chitwoodi and M. fallax are quarantine organisms and subject to regulations, and the highly aggressive M. enterolobii has been added to the EPPO alert list. Differences between temperate and tropical Meloidogyne species and their prevalence in Europe imply the need for different management strategies in south and north Europe. Possible crop rotations for the control of root-knot nematodes are limited due to the wide host range of several important species. The banning of methyl bromide and restrictions on other fumigant pesticides in the EU have increased the application of biofumigation significantly in south Europe. The egg-parasitising fungus Paecilomyces lilacinus is commercialised in Germany and applied as dispersible granules for application in water. Intensive research is conducted on the egg-parasitising fungus Pochonia chlamydosporia, and the obligate parasitic bacterium Pasteuria penetrans. European research has paid much attention to resistance breeding and selection. The Mi gene of tomato is widely used but resistance-breaking populations of M. incognita and M. javanica have been reported in different countries.

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Mitochondrial DNA differences distinguishing Meloidogyne mayaguensis from the major species of tropical root-knot nematodes

Nematology ◽

10.1163/156854102760402559 ◽

2002 ◽

Vol 4 (7) ◽

pp. 773-781 ◽

Cited By ~ 40

Author(s):

Vivian Blok ◽

Mireille Fargette ◽

Jane Wishart ◽

Mark Phillips ◽

Karine Berthier

Keyword(s):

Mitochondrial Dna ◽

Molecular Diagnostics ◽

Tandem Repeat ◽

Economic Damage ◽

Repeat Region ◽

Root Knot Nematode ◽

Accurate Identification ◽

Major Species ◽

Tandem Repeat Region ◽

Meloidogyne Spp

Abstract- The mitochondrial DNA region between the COII and lRNA genes and the 63 base pair tandem repeat region have been used to differentiate and characterise Meloidogyne spp. In this study these regions have been amplified from M. mayaguensis, M. javanica, M. arenaria, M. incognita and M. hapla. Meloidogyne mayaguensis produces a unique product of 705 bp from the COII and lRNA region. Also, a product of 322 bp was produced from the 63 bp repeat region of M. mayaguensis unlike M. javanica, M. arenaria, and M. incognita that exhibit hypervariability in this region. Meloidogyne mayaguensis is a widely distributed root-knot nematode with the potential to cause great economic damage. These molecular diagnostics can be used for accurate identification of M. mayaguensis and can be used to monitor the occurrence and spread of this species, and to provide quarantine services tools to limit its dispersal.

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Characterization of Resistance to Major Tropical Root-Knot Nematodes (Meloidogyne spp.) in Solanum sisymbriifolium

Phytopathology ◽

10.1094/phyto-10-19-0393-r ◽

2020 ◽

Vol 110 (3) ◽

pp. 666-673 ◽

Cited By ~ 1

Author(s):

Abolfazl Hajihassani ◽

William B. Rutter ◽

Tanner Schwarz ◽

Moges Woldemeskel ◽

Md Emran Ali ◽

...

Keyword(s):

Management Strategies ◽

Yield Reduction ◽

Initial Population ◽

Multiplication Rate ◽

Tomato Crop ◽

Root Knot Nematodes ◽

Major Species ◽

Meloidogyne Spp ◽

White Star ◽

Solanum Sisymbriifolium

Root-knot nematodes (Meloidogyne spp.) are important contributors to yield reduction in tomato. Though resistant cultivars to common species (Meloidogyne arenaria, M. incognita, and M. javanica) are available, they are not effective against other major species of root-knot nematodes. Cultivars or lines of Solanum sisymbriifolium were examined to assess the presence and level of resistance to five major species: M. arenaria race 1, M. incognita race 3, M. haplanaria, M. javanica, and M. enterolobii. Differences in S. sisymbriifolium response to the nematode infection were apparent when susceptibility or resistance was classified by the egg counts per gram fresh weight of root and the multiplication rate of the nematodes. The cultivar Diamond was highly susceptible, Quattro and White Star were susceptible, while Sis Syn II was resistant to M. arenaria. Quattro, White Star, and Sis Syn II exhibited a moderate to high level of resistance to M. incognita but the nematode increased 2.5-fold from the initial population of the M. incognita on Diamond. All S. sisymbriifolium cultivars were highly resistant to both M. haplanaria and M. enterolobii, while highly susceptible to M. javanica. A microplot study under field conditions using Sis Syn II confirmed that M. arenaria, M. incognita, and M. haplanaria were not pathogenic on the plant. Likewise, an examination on cross-sections of galled root tissues confirmed the susceptibility and resistance of S. sisymbriifolium lines to Meloidogyne spp. Using S. sisymbriifolium as a resistant rootstock or a new source of resistance may result in the development of nonchemical and sustainable management strategies to protect the tomato crop.

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Morphological and morphometrical identification of Meloidogyne populations from various crop production areas in South Africa with emphasis on M. enterolobii

Zootaxa ◽

10.11646/zootaxa.4658.2.3 ◽

2019 ◽

Vol 4658 (2) ◽

pp. 251-274

Author(s):

MILAD RASHIDIFARD ◽

HENDRIKA FOURIE ◽

MIEKE STEFANIE DANEEL ◽

MARIETTE MARAIS

Keyword(s):

South Africa ◽

Crop Production ◽

Management Strategies ◽

Morphological Characteristics ◽

Molecular Techniques ◽

Accurate Identification ◽

Morphometric Characters ◽

Geographical Regions ◽

Meloidogyne Spp ◽

Production Areas

Accurate identification of Meloidogyne spp. is crucial and the first step to apply suitable management strategies to combat these nematode pests. Perineal-pattern morphology of female specimens is one of the most common characteristics used for identification. However, for some species various morphological characteristics are similar which makes it challenging to correctly identify species. In this study different morphological and morphometrical characteristics were used to identify 37 populations of Meloidogyne obtained during 2015 and 2016 from various crop production areas situated across different geographical regions in South Africa. A comprehensive study of females, males and second-stage juveniles (J2) of the 37 Meloidogyne populations isolated was conducted, revealing the presence of Meloidogyne enterolobii, M. hapla, M. incognita and M. javanica. Although three perineal-pattern characteristics proved to be useful in discriminating particularly between M. enterolobii and M. incognita females, most of the morphometric characters used to identify female, male and J2 individuals overlapped among the different species. Substantial intraspecies variation was also evident among different populations. The use of classical identification approaches alone could therefore not clearly distinguish among the 37 Meloidogyne populations studied. Therefore, the use of molecular techniques in combination with morphological and morphometrical analyses is suggested to be more accurate and reliable in discriminating between Meloidogyne spp.

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Genetic diversity of Meloidogyne spp. parasitising potato in Brazil and aggressiveness of M. javanica populations on susceptible cultivars

Nematology ◽

10.1163/15685411-00003032 ◽

2017 ◽

Vol 19 (1) ◽

pp. 69-80 ◽

Cited By ~ 9

Author(s):

Israel L. Medina ◽

Cesar B. Gomes ◽

Valdir R. Correa ◽

Vanessa S. Mattos ◽

Philippe Castagnone-Sereno ◽

...

Keyword(s):

Genetic Diversity ◽

Rapd Markers ◽

Potato Production ◽

Potato Cultivars ◽

Root Knot Nematode ◽

Root Knot Nematodes ◽

Nematode Reproduction ◽

Meloidogyne Spp ◽

Prevalent Species ◽

Reproduction Factor

Root-knot nematodes (Meloidogyne spp.) significantly impact potato production worldwide and in Brazil they are considered one of the most important group of nematodes affecting potatoes. The objectives of this study were to survey Meloidogyne spp. associated with potatoes in Brazil, determine their genetic diversity and assess the aggressiveness of M. javanica on two susceptible potato cultivars. Fifty-seven root-knot nematode populations were identified using esterase phenotyping, including Meloidogyne javanica, M. incognita, M. arenaria and M. ethiopica. Overall, root-knot nematodes were present in ca 43% of sampled sites, in which M. javanica was the most prevalent species, and the phenotypes Est J3, J2a and J2 occurred in 91.2, 6.7 and 2.1% of the positive samples, respectively. Other species, such as M. incognita, M. arenaria and M. ethiopica, were found less frequently and occurred at rates of 6.4, 4.3 and 2.1% of the samples, respectively. Sometimes, M. javanica was found in mixtures with other root-knot nematodes in ca 10.6% of sites containing Meloidogyne. After confirming the identification of 17 isolates of M. javanica and one isolate each of M. incognita, M. arenaria and M. ethiopica by SCAR markers, the populations were used to infer their genetic diversity using RAPD markers. Results revealed low intraspecifc genetic diversity among isolates (13.9%) for M. javanica. Similarly, M. javanica sub-populations (J2a) clustered together (81% of bootstrap), indicating subtle variation from typical J3 populations. The aggressiveness of four populations of M. javanica from different Brazilian states on two susceptible potato cultivars was tested under glasshouse conditions. Results indicated differences in aggressiveness among these populations and showed that potato disease was proportional to nematode reproduction factor.

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First Report of the Root-Knot Nematode Meloidogyne floridensis on Tomato (Lycopersicon esculentum) in Florida

Plant Disease ◽

10.1094/pd-89-0527b ◽

2005 ◽

Vol 89 (5) ◽

pp. 527-527

Author(s):

G. T. Church

Keyword(s):

Lycopersicon Esculentum ◽

Field Experiments ◽

The United States ◽

The State ◽

Bromophenol Blue ◽

Root Knot Nematode ◽

Fresh Market ◽

Root Knot Nematodes ◽

First Report ◽

Meloidogyne Spp

The state of Florida is the largest producer of fresh market tomato (Lycopersicon esculentum L.) in the United States with 2003 yields of 634 million kg on 17,700 ha valued at 516 million dollars. Effective crop management is essential for production of vegetables in Florida because of the presence of intense pest pressure. The identification of the pests present is the first step in the development of a successful IPM (integrated pest management) program. Root-knot nematodes (Meloidogyne spp.) are common nematodes that parasitize vegetables in Florida and cause significant yield reductions when not properly managed. In 2003 field experiments, soil was collected from two research farms in Saint Lucie and Seminole counties in Florida. Galling caused by root-knot nematode was observed on tomato at both locations. Since females suitable for identification are difficult to obtain from field-grown roots, field soil was placed in pots in the greenhouse and planted with Lycopersicon esculentum cv. Rutgers. Standard morphological techniques, differential host tests, and isozyme phenotypes were used in nematode identification. Female root-knot nematodes were extracted from tomato roots and placed in extraction buffer (10% wt/vol sucrose, 2% vol/vol Triton X-100, 0.01% wt/vol bromophenol blue). The females were crushed, loaded on a polyacrylamide gel, and separated by electrophoresis using the PhastSystem (Amersham Biosciences, Piscataway, NJ). The activities of malate dehydrogenase and esterase enzymes were detected using standard techniques. Isozyme phenotypes consistent with Meloidogyne incognita (Kofoid and White) Chitwood and M. javanica (Treub) Chitwood as well as with the newly described M. floridensis Handoo (1) were observed at both locations. To our knowledge, this is the first report of M. floridensis naturally occurring on tomato in Florida. The identification and distribution of M. floridensis in vegetable production fields is important for disease management throughout the state since the host range is likely different from other Meloidogyne spp. Reference: (1) Z. A. Handoo et al. J. Nematol. 36:20, 2004.

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Marigold (Tagete erecta): An Effective Meloidogyne incognita Trap Plant

International Journal of Agriculture and Biology ◽

10.17957/ijab/15.1666 ◽

2021 ◽

Vol 25 (02) ◽

pp. 271-276

Author(s):

Wentao Wu

Keyword(s):

Root Exudates ◽

Host Plants ◽

Inhibitory Effect ◽

Root Knot Nematode ◽

Root Cells ◽

Biological Pest Control ◽

Root Knot Nematodes ◽

Meloidogyne Spp ◽

Trap Plants ◽

Strong Inhibitory Effect

Root-knot nematodes (Meloidogyne spp.) are soil-borne pathogens that can cause severe damage to agricultural production. The most common approaches to prevent root-knot nematode infections are based on crop rotation with non-host plants, use of chemical insecticides, biological control methods, and use of nematode-antagonistic or trap plants. Marigolds (Tagetes erecta) are used as nematode-killing plants, but there is controversy over the mechanism through which they control root-knot nematodes. This study confirmed that marigold root-exudates are lethal to root-knot nematodes, illustrated that marigolds act as trap plants for root-knot nematodes when planted close to nematode host plants such as tomato. We investigated the rates of infection and development of nematode larvae injected into the marigold root system to evaluate whether marigolds could act as a non-host plant for root-knot nematodes. We found that aqueous solutions of marigold root-exudates showed strong lethal and inhibitory effects on sec-stage juveniles and eggs of root-knot nematodes. Marigold roots secreted substances that attracted nematodes from the surrounding environment. Furthermore, marigold root cells contained substances that had a strong inhibitory effect on the development of root-knot nematodes, resulting in diapause in nematodes, and inhibition of further infection. Herein we report a preliminary exploration of the antagonistic mechanism in marigolds for controlling the growth and development of root-knot nematodes. Our research provides basis for promoting the use of marigold for the control of nematodes as an important part of sustainable cropping strategies that rely on biological pest control. © 2021 Friends Science Publishers

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Community Analysis of Nematodes Associated with Banana, Identification of root knot nematode and Evaluation the Susceptibility of Some Cultivars to Infection

10.21203/rs.3.rs-740928/v1 ◽

2021 ◽

Author(s):

Radwa G. Mostafa ◽

Aida M. El-Zawahry ◽

Ashraf E. M. Khalil ◽

Ameer E. Elfarash ◽

Ali D. A. Allam

Keyword(s):

Meloidogyne Javanica ◽

Nematode Species ◽

Common Species ◽

Molecular Techniques ◽

Control Measures ◽

Parasitic Nematodes ◽

Plant Parasitic Nematodes ◽

Root Knot Nematode ◽

Root Knot Nematodes ◽

Plant Parasitic

Abstract Background Plant-parasitic nematodes are extremely dangerous pests in a variety of economically important crops. The purpose of this study was a survey of all nematode species existing in banana from three sites in Assiut Governorate, Egypt and to characterize the most common species by morphological, morphometric and molecular techniques (PCR with species-specific primers). Then, study of resistance or sensitivity of some banana cultivars to root-knot nematodes.Methods and Results Four nematodes, Meloidogyne, Rotylenchulus reniformis, Helicotylenchus and Pratylenchus were isolated and identified from soil and root samples collected from banana plants. Most frequently occurring of plant parasitic nematode species in banana was Meloidogyne. Former research found differences in species and in resistance to root-knot nematodes among the examined plant cultivars. Identification of Root-knot nematodes by Characterize of morphometric, molecularly, morphological isolate of Meloidogyne related to banana plants. The results revealed that the identified nematode species, Meloidogyne javanica, is the most common plant-parasitic nematodes in all locations. Data on the susceptibility of the tested banana cultivars to M. javanica revealed that Grand Naine was highly susceptible (HS) however, Magraby was susceptible (S) but Williams and Hindi cultivars were moderately resistant (MR).Conclusions we concluded that a survey revealed the significant prevalence of Meloidogyne javanica, the most important nematodes on banana in Assiut. The morphometric, morphological, and molecular identification were harmonic with one another. In addition to the host response of certain banana cultivars, to M. javanica that resistance is of significance and can be helpful to incorporate through planning control measures for root- knot nematodes.

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Meloidogyne Species Associated with Weeds in Rio Grande do Sul

Planta Daninha ◽

10.1590/s0100-83582019370100095 ◽

2019 ◽

Vol 37 ◽

Cited By ~ 1

Author(s):

C. BELLÉ ◽

T.E. KASPARY ◽

R.R. BALARDIN ◽

R.F. RAMOS ◽

Z.I. ANTONIOLLI

Keyword(s):

Host Plants ◽

Management Practices ◽

Rio Grande ◽

Meloidogyne Javanica ◽

Rio Grande Do Sul ◽

Weed Species ◽

Root Knot Nematode ◽

Root Knot Nematodes ◽

Meloidogyne Spp ◽

Meloidogyne Species

ABSTRACT: The frequency of species of root-knot nematodes (Meloidogyne spp.) was evaluated in weeds collected in different fallow farms in the State of Rio Grande do Sul, Brazil. In the samples where the nematode was found, the species of the root-knot nematode was identified by electrophoresis using the isozyme esterase. They were obtained from weeds belonging to 24 weed species from 13 different botanical families: Amaranthaceae, Asteraceae, Commelinaceae, Convovulaceae, Cyperaceae, Euphorbiaceae, Lamiaceae, Malvaceae, Oxalidaceae, Poaceae, Portulacaceae, Solanaceae, Verbenaceae. Meloidogyne javanica Est J3 (Rm: 1.0, 1.25, 1.40) was the most frequent species and occurred in 53.3% of the samples. M. arenaria with phenotype Est. A2 (Rm: 1.20, 1.30) was detected in 15.6% of the samples. M. incognita Est. I2 (Rm: 1.0, 1.1), M. ethiopica Est. E3 (Rm: 0.9, 1.15, 1.30), M. enterolobii Est. M2 (Rm: 0.7, 0.75, 0.9, 0.95) and M. hapla Est. H1 (Rm: 1.17) in 13.3%, 8.9%, 6.7% and 2.2% of the samples, respectively. Therefore, knowledge of the range of host plants to different species of the root-knot nematode can positively contribute to the adoption of management practices that allow the reduction of their populations in the soil.

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Management of Root Knot Nematode on Tomato through Grafting Root Stock of Solanum sisymbriifolium

Journal of Nepal Agricultural Research Council ◽

10.3126/jnarc.v3i1.17272 ◽

2017 ◽

Vol 3 ◽

pp. 27-31 ◽

Cited By ~ 4

Author(s):

Suraj Baidya ◽

Ram Devi Timila ◽

Ram Bahadur KC ◽

Hira Kaji Manandhar ◽

Chetana Manandhar

Keyword(s):

Agricultural Research ◽

Tomato Fruit ◽

Fruit Yield ◽

Root Knot Nematode ◽

Root Knot Nematodes ◽

Tomato Plants ◽

Agricultural Research Council ◽

Root Stock ◽

Meloidogyne Spp ◽

Solanum Sisymbriifolium

The root-knot nematodes (Meloidogyne spp) are difficult to manage once established in the field because of their wide host range, and soil-borne nature. Thus, the aim of the present study was to examine the use of resistant root stock of wild brinjal (Solanum sisymbriifolium) to reduce the loss caused by the nematodes on tomato. For the management of root-knot nematodes, grafted plant with resistant root stock of the wild brinjal was tested under farmers’ field conditions at Hemza of Kaski district. Grafted and non-grafted plants were produced in root-knot nematode-free soil. Around three week-old grafted and non-grafted tomato plants were transplanted in four different plastic tunnels where root-knot nematodes had been reported previously. The plants were planted in diagonal position to each other as a pair plot in 80 × 60 cm2 spacing in an average of 20 × 7 m2 plastic tunnels. Galling Index (GI) was recorded three times in five randomly selected plants in each plot at 60 days intervals. The first observation was recorded two months after transplanting. Total fruit yield was recorded from same plants. In the grafted plants, the root system was totally free from gall whereas in an average of 7.5 GI in 0-10 scale was recorded in the non-grafted plants. Fruits were harvested from time to time and cumulated after final harvest to calculate the total fruit yield. It was estimated that on an average tomato fruit yield was significantly (P>0.05) increased by 37 percent in the grafted plants compared with the non-grafted plants. Grafting technology could be used effectively for cultivation of commonly grown varieties, which are susceptible to root-knot nematodes in disease prone areas. This can be used as an alternative technology for reducing the use of hazardous pesticides for enhancing commercial organic tomato production.Journal of Nepal Agricultural Research Council Vol.3 2017: 27-31

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