Differences in Feeding Sites Induced by Root-Knot Nematodes, Meloidogyne spp., in Chickpea

Root-knot nematodes (Meloidogyne spp.) are sedentary, obligate endoparasites in plants, where they induce specialized feeding sites. The feeding sites act as strong metabolic sinks to which photosynthates are mobilized. The histopathological modifications in the nematode-induced feeding sites of artificially inoculated chickpea cv. UC 27 were qualitatively and quantitatively compared using five isolates of M. artiellia and one isolate each of M. arenaria, M. incognita, and M. javanica. All Meloidogyne isolates infected chickpea plants, but root gall thickening was significantly less for M. artiellia isolates than for the other Meloidogyne species. Nevertheless, neither the number of giant cells in the feeding site (averaging four to six) nor the area of individual giant cells was influenced by nematode species or isolate. However, the number of nuclei per giant cell was significantly smaller, and the maximum diameters of nuclei and nucleoli were significantly greater, in giant cells induced by M. artiellia isolates than in those induced by M. arenaria, M. incognita, or M. javanica. In a second experiment, M. artiellia-induced giant cells in faba bean and rapeseed also contained a small number of large nuclei.

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Local and Systemic Induced Resistance to the Root-Knot Nematode in Tomato by DL-β-Amino-n-Butyric Acid

Phytopathology ◽

10.1094/phyto.1999.89.12.1138 ◽

1999 ◽

Vol 89 (12) ◽

pp. 1138-1143 ◽

Cited By ~ 69

Author(s):

Yuji Oka ◽

Yigal Cohen ◽

Yitzhak Spiegel

Keyword(s):

Butyric Acid ◽

Foliar Spray ◽

Giant Cells ◽

Root Knot Nematode ◽

Root Knot Nematodes ◽

Tomato Plants ◽

Feeding Site ◽

Chemical Inducers ◽

Site Development ◽

Tomato Roots

Chemical inducers of pathogenesis-related proteins and plant resistance were applied to tomato plants, with the aim of inducing resistance to the root-knot nematode Meloidogyne javanica. Relative to control plants, foliar spray and soil-drenching with dl-β-amino-n-butyric acid (BABA) reduced root-galling 7 days after inoculation, as well as the number of eggs 30 days after inoculation. Other chemicals (α- and γ-amino-n-butyric acid, jasmonic acid, methyl jasmonate, and salicylic acid) were either phytotoxic to tomato plants or did not improve control of root-knot nematodes. Fewer second-stage juveniles invaded BABA-treated tomato roots, and root-galling indices were lower than in control tomato plants. Resistance phenomena in seedlings lasted at least 5 days after spraying with BABA. Nematodes invading the roots of BABA-treated seedlings induced small, vacuolate giant cells. Postinfection treatment of tomato plants with BABA inhibited nematode development. It is speculated that after BABA application tomato roots become less attractive to root-knot nematodes, physically harder to invade, or some substance(s) inhibiting nematode or nematode feeding-site development is produced in roots.

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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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PIGEONS' CHOICE BETWEEN SHARED AND UNSHARED FEEDING SITES IN GAME SITUATIONS.

Revista Mexicana de Análisis de la Conducta ◽

10.5514/rmac.v45.i2.75576 ◽

2019 ◽

Vol 45 (2) ◽

pp. 434-453

Author(s):

Shoko Kitano ◽

Tetsuo Yamaguchi ◽

Daisuke Saeki ◽

Masato Ito

Keyword(s):

Present Experiment ◽

Prisoner's Dilemma ◽

Prisoner’S Dilemma ◽

The Other ◽

Choice Situation ◽

Prisoner’S Dilemma Game ◽

Feeding Site ◽

Feeding Sites ◽

Choice Strategy ◽

Tit For Tat

Cooperative behavior in nonhuman animals has been studied within the framework of game theory, typically by using the prisoner’s dilemma game. Previous studies on cooperation by pigeons using this game have revealed that, under these conditions, the animals did not learn the tit-for-tat strategy played by their opponents. In many cases, animals fail to choose cooperation and in so doing do not maximize their gains. The present experiment examined pigeons’ cooperative choices in the prisoner’s dilemma game situation by using a different type of apparatus than that used in previous studies: Subjects moved to choose one of two feeding sites, one of which was shared by another, stooge, pigeon whose choices were controlled by a computer and the other of which was not shared by other pigeons. In this choice situation, the presence of the stooge pigeon increased the subjects’ choices of the shared feeding site significantly. Further, the pigeons learned the other player’s choice strategy (tit-for-tat and random), showing that choice proportions for the shared feeding site were significantly higher in the tit-for-tat condition than in the random condition. These results suggest that the presence of a conspecific at the feeding site is a reinforcer for choosing it and that the choice situation constituted by the apparatus used in the present experiment could promote learning of the opponent’s choice strategy.

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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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Nematode-Induced Changes of Transporter Gene Expression in Arabidopsis Roots

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-18-1247 ◽

2005 ◽

Vol 18 (12) ◽

pp. 1247-1257 ◽

Cited By ~ 89

Author(s):

Ulrich Z. Hammes ◽

Daniel P. Schachtman ◽

R. Howard Berg ◽

Erik Nielsen ◽

Wolfgang Koch ◽

...

Keyword(s):

Gene Families ◽

Transcript Abundance ◽

Giant Cells ◽

Transport Processes ◽

Transfer Cells ◽

Parasitic Nematodes ◽

Feeding Site ◽

Feeding Sites ◽

The Many ◽

And Function

Root-knot plant-parasitic nematodes (Meloidogyne spp.) account for much of the damage inflicted to plants by nematodes. The feeding sites of these nematodes consist of “giant” cells, which have characteristics of transfer cells found in other parts of plants. Increased transport activity across the plasma membrane is a hallmark of transfer cells, and giant cells provide nutrition for nematodes; therefore, we initiated a study to identify the transport processes that contribute to the development and function of nematode-induced feeding sites. The study was conducted over a 4-week period, during which time the large changes in the development of giant cells were documented. The Arabidopsis ATH1 GeneChip was used to identify the many transporter genes that were regulated by nematode infestation. Expression of 50 transporter genes from 18 different gene families was significantly changed upon nematode infestation. Sixteen transporter genes were studied in more detail using real-time reverse-transcriptase polymerase chain reaction to determine transcript abundance in nematode-induced galls that contain giant cells and uninfested regions of the root. Certain genes were expressed primarily in galls whereas others were expressed primarily in the uninfested regions of the root, and a third group was expressed evenly throughout the root. Multiple transport processes are regulated and these may play important roles in nematode feeding-site establishment and maintenance.

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Effectors of Root-Knot Nematodes: An Arsenal for Successful Parasitism

Frontiers in Plant Science ◽

10.3389/fpls.2021.800030 ◽

2021 ◽

Vol 12 ◽

Author(s):

Shounak Jagdale ◽

Uma Rao ◽

Ashok P. Giri

Keyword(s):

Plant Immunity ◽

Plant Defence ◽

Giant Cells ◽

Parasitic Nematodes ◽

Plant Parasitic Nematodes ◽

Root Knot Nematodes ◽

Feeding Sites ◽

The Past ◽

Complex Functions ◽

Insight Into

Root-knot nematodes (RKNs) are notorious plant-parasitic nematodes first recorded in 1855 in cucumber plants. They are microscopic, obligate endoparasites that cause severe losses in agriculture and horticulture. They evade plant immunity, hijack the plant cell cycle, and metabolism to modify healthy cells into giant cells (GCs) – RKN feeding sites. RKNs secrete various effector molecules which suppress the plant defence and tamper with plant cellular and molecular biology. These effectors originate mainly from sub-ventral and dorsal oesophageal glands. Recently, a few non-oesophageal gland secreted effectors have been discovered. Effectors are essential for the entry of RKNs in plants, subsequently formation and maintenance of the GCs during the parasitism. In the past two decades, advanced genomic and post-genomic techniques identified many effectors, out of which only a few are well characterized. In this review, we provide molecular and functional details of RKN effectors secreted during parasitism. We list the known effectors and pinpoint their molecular functions. Moreover, we attempt to provide a comprehensive insight into RKN effectors concerning their implications on overall plant and nematode biology. Since effectors are the primary and prime molecular weapons of RKNs to invade the plant, it is imperative to understand their intriguing and complex functions to design counter-strategies against RKN infection.

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The Incidence of Root-Knot Nematodes Meloidogyne arenaria, M. incognita, and M. javanica on Vegetables and Weeds in Montenegro

Plant Disease ◽

10.1094/pdis-91-11-1514b ◽

2007 ◽

Vol 91 (11) ◽

pp. 1514-1514 ◽

Cited By ~ 1

Author(s):

I. Pajovic ◽

S. Širca ◽

B. Geric Stare ◽

G. Urek

Keyword(s):

Nematode Species ◽

Early Spring ◽

Management Program ◽

Egg Laying ◽

Vegetable Production ◽

Meloidogyne Arenaria ◽

Vegetable Crops ◽

Cucumis Sativus L ◽

Root Knot Nematodes ◽

Meloidogyne Spp

Root-knot nematodes (Meloidogyne spp.) are common pathogens that parasitize vegetables and other crops and cause significant yield reductions worldwide. In the early spring of 2006, severe plant stunting, chlorosis, and extensive root galling were observed on cucumber plants grown in a greenhouse on Zeta plain, Zetska ravnica, Montenegro. In the summer and autumn of 2006, infected roots of different crops were collected from greenhouses and vegetable production fields of Zeta plain, which represents the largest area of Montenegro's vegetable production. Several vegetable crops were found to be infected with root-knot nematodes, including tomato (Lycopersicon esculentum Mill.), squash (Cucurbita pepo L.), cucumber (Cucumis sativus L.), pepper (Capsicum annuum L.), and lettuce (Lactuca sativa L.). Symptoms on these crops included root-galling, leaf chlorosis, and stunting. Heavily infected tomato plants growing in two greenhouses also displayed early flower and fruit drop. Nematode species were determined based on characterization of (i) female perineal patterns, (ii) male and second-stage juvenile morphology (2,3), and (iii) esterase and malate dehydrogenase phenotypes (PhastSystem; Amersham Biosciences, Piscataway, NJ) from young egg-laying females (1). The most prevalent species was M. incognita, which was isolated from the roots of tomatoes, peppers, cucumbers, and lettuce from nine locations. Meloidogyne arenaria was detected at three locations from the roots of tomatoes grown in a greenhouse and the weeds Convolvulus arvensis L. and Solanum nigrum L., which were growing in open fields in separate locations. M. javanica was found on tomato and squash in the same field where M. arenaria was also found on S. nigrum. M. javanica was isolated from tomato and squash. In this study, we found high incidence of Meloidogyne spp. in intensive vegetable production areas of Montenegro. The implementation of an effective integrated pest management program is essential for future use of infested areas. To our knowledge, this is the first report of M. arenaria, M. incognita, and M. javanica from Montenegro. References: (1) P. R. Esbenshade and A. C. Triantaphyllou. J. Nematol. 17:6, 1985. (2) S. B. Jepson. Identification of Root-Knot Nematodes. CAB International, Wallingford, UK, 1987. (3) G. Karssen. The Plant-Parasitic Nematode Genus Meloidogyne Göldi, 1892 (Tylenchida) in Europe. Koninklijke Brill NV, Leiden, the Netherlands, 2002.

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Characterization of lettuce genotypes for resistance to root-knot nematodes (Meloidogyne spp.)

Horticultura Brasileira ◽

10.1590/s0102-053620200301 ◽

2020 ◽

Vol 38 (3) ◽

pp. 239-245

Author(s):

Jadir B Pinheiro ◽

Giovani Olegário da Silva ◽

Danielle Biscaia ◽

Amanda G Macedo ◽

Fábio A Suinaga

Keyword(s):

Genetic Resistance ◽

Nematode Species ◽

Egg Mass ◽

Root Knot Nematodes ◽

Grand Rapids ◽

Race 1 ◽

Meloidogyne Spp ◽

Susceptible Control ◽

Gall Index

ABSTRACT Genetic resistance is the most suitable mechanism to control root-knot nematodes in lettuce. However, information about the resistance levels of currently used lettuce cultivars is scarce in the literature. Thus, the objective of this research was to characterize lettuce cultivars for resistance to root-knot nematodes Meloidogyne incognita (Mi) and M. javanica (Mj), aiming the identification of resistance sources for breeding, and to transfer information to the productive sector. We evaluated 97 lettuce genotypes in tree trials. In the first one (preliminary assessment), 92 lettuce genotypes were inoculated simultaneously with M. incognita race 1 and M. javanica species, 17 days after sowing. The gall index (GI) was evaluated 41 days after inoculation. In the second trial nine genotypes, selected from the first trial, were evaluated; and in the third trial, two new cultivars from Embrapa were evaluated. In the last two trials, the nematode species were inoculated separately, and the egg mass index (EMI), number of eggs per gram of roots (NEGR) and reproduction factor (RF) were also evaluated. In both trials, the lettuce cultivars Salinas 88 and Grand Rapids were used as resistant controls, as well as cultivar Irene as the susceptible control. The data were submitted to analysis of variance and treatments means grouping by Scott-Knott´s test. The crisp leaf cultivars presented a higher degree of resistance to the root-knot nematodes compared to the smooth leaf type cultivars. Cultivars Vera and Amanda present resistance to M. incognita, and Vanda to M. javanica. ‘Salinas 88’ present resistance mainly to M. javanica; while cultivar Mônica and the Embrapa cultivars BRS Leila and BRS Mediterrânea are resistant to both nematode species.

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First Report of Root-Knot Nematodes (Meloidogyne spp.) on Sunflowers in Mozambique

Plant Disease ◽

10.1094/pdis.1997.81.11.1333e ◽

1997 ◽

Vol 81 (11) ◽

pp. 1333-1333 ◽

Cited By ~ 2

Author(s):

A. Zazzerini ◽

L. Tosi ◽

P. M. Vicente

Keyword(s):

South African ◽

Personal Communication ◽

Nematode Species ◽

Root Knot Nematode ◽

African Countries ◽

Root Knot Nematodes ◽

First Report ◽

Alternaria Helianthi ◽

Disease Surveys ◽

Meloidogyne Spp

Sunflower (Helianthus annuus L.) recently was reintroduced to Mozambique because of renewed interest in oil-seed production for domestic consumption. In April 1997, disease surveys were carried out in two fields in southern Mozambique (Maputo region). Several plants of Pan 735, a South African cultivar, showed yellowing of the leaves and stunting. These plants wilted during the day but recovered their turgidity at night. Diseased plants were easily pulled from the soil due to almost complete destruction of the root system. Numerous galls were found on affected roots, compared with healthy plants. Meloidogyne javanica (Treub) Chitwood and M. incognita (Kofoid & White) Chitwood were identified by M. Di Vito (personal communication) based on 20 female perineal patterns observed with a light microscope. M. incognita was more prevalent than M. javanica. Also observed were Alternaria helianthi (Hansf.) Tubaki & Nishihara and Sclerotium bataticola Taub. Root-knot nematodes (Meloidogyne spp.), common on sunflower, cause severe damage and reduce both seed yield and seed oil content (1). These two nematode species have also been observed on sunflower in other African countries (Zambia, South Africa, Egypt) but this is the first report of root-knot nematode on sunflower in Mozambique. Reference: (1) M. Di Vito et al. Nematol. Medit. 24:109, 1996.

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Auxin induction is a trigger for root gall formation caused by root-knot nematodes in white clover and is associated with the activation of the flavonoid pathway

Functional Plant Biology ◽

10.1071/pp98157 ◽

1999 ◽

Vol 26 (3) ◽

pp. 221 ◽

Cited By ~ 68

Author(s):

Pokkwan Hutangura ◽

Ulrike Mathesius ◽

Mike G. K. Jones ◽

Barry G. Rolfe

Keyword(s):

Giant Cell ◽

White Clover ◽

Chalcone Synthase ◽

Giant Cells ◽

Post Inoculation ◽

Flavonoid Pathway ◽

Root Knot Nematodes ◽

Auxin Distribution ◽

Gusa Reporter Gene ◽

Auxin Accumulation

We studied the expression of the auxin responsive promoter (GH3) fused to the gusA reporter gene in white clover (Trifolium repens cv. Haifa) during the initiation of root galls by root-knot nematodes (Meloidogyne javanica) to investigate whether nematode infection affects auxin distribution in developing galls. In search for a plant signal that would mediate changes in auxin location we studied the induction of the flavonoid pathway because flavonoids can act as auxin transport regulators. Three chalcone synthase (CHS1, CHS2 and CHS3) promoter:gusA fusions were examined in transgenic plants and flavonoids were detected using fluorescence microscopy. Within 24 h post inoculation CHS:gusA expression occurred around the invading nematode. At 48 h post inoculation CHS:gusA expression and flavonoids were detected throughout the infection site, followed by high GH3:gusA expression in the gall 48–72 h post inoculation. Initially (48–72 h post inoculation) high GH3:gusA expression in giant cell precursors was followed by low expression in the enlarging giant cells (96–120 h post inoculation), suggesting that auxin is needed as a trigger for giant cell initiation but not for later enlargement. We suggest that nematodes control auxin distribution in the root and that flavonoids could be responsible for controlling auxin accumulation.

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