Search

A major problem for potato production worldwide is Globodera rostochiensis. Field control of this nematode is difficult because of the high reproductive rate of this genus and its resistance to biotic and abiotic factors. Biological control of nematodes is an increasingly popular strategy because it is effective and has low environmental impact. In this study, the potential of the nematophagous fungus Metarhizium carneum to mitigate the G. rostochiensis population in the presence of a susceptible potato host without previous management and during two crop cycles was evaluated, which included cultivation of the non-host faba bean followed by a susceptible potato crop. The effect of M. carneum application to the soil allowing the field to remain fallow for 2 years was also evaluated. Although M. carneum reduced the G. rostochiensis population by 33% during one potato crop cycle, the yield did not increase. With the application of M. carneum and a faba bean/potato rotation, the nematode population in the soil was reduced by 81%, with a significant increase in yield. Likewise, the use of the fungal biological control agent and the fallow period resulted in an 87% reduction in the nematode population after 2 years. Additionally, Rhizoctonia solani damage in tubers to which M. carneum was applied was lower than that in non-treated tubers in both experiments. The reduction in the population density of G. rostochiensis without the application of the biological control agent, including in the crop rotation and fallow treatments, was very low in both experiments. The combination of two management strategies, such as the use of biological control and crop rotation or a fallow period, may be a viable approach for the integrated management of G. rostochiensis in areas where high densities of this nematode occur.

The fabrication of fungicides in cost-effective and eco-friendly ways is particularly important for agriculture. Plant pathogenic fungi produce many economic and ecological problems worldwide, which must be controlled with potent fungicides. Here we propose the green synthesis of fungicides, which consist of copper nanoparticles (Cu-NPs) prepared in aqueous media. Through in vitro experiments, the antifungal efficacy against Fusarium solani, Neofusicoccum sp., and Fusarium oxysporum was investigated. Although the antifungal activity differs for each fungal species, it was found that the Cu-NPs induce strong morphological changes in the mycelium. Additionally, the damage of the cell membranes of the pathogens was revealed by microscopic observations. For the three evaluated fungi, fluorescence microscopy demonstrated the intracellular generation of reactive oxygen species in the mycelium. This work proves that the green-synthesized Cu-NPs are potential fungicides against F. solani, Neofusicoccum sp., and F. oxysporum.

Microbial volatile organic compounds (mVOCs) play important roles in inter- and intra-kingdom interactions, and they are also important as signal molecules in physiological processes acting either as plant growth-promoting or negatively modulating plant development. We investigated the effects of mVOCs emitted by PGPR vs non-PGPR from avocado trees (Persea americana) on growth of Arabidopsis thaliana seedlings. Chemical diversity of mVOCs was determined by SPME–GC–MS; selected compounds were screened in dose–response experiments in A. thaliana transgenic lines. We found that plant growth parameters were affected depending on inoculum concentration. Twenty-six compounds were identified in PGPR and non-PGPR with eight of them not previously reported. The VOCs signatures were differential between those groups. 4-methyl-2-pentanone, 1-nonanol, 2-phenyl-2-propanol and ethyl isovalerate modified primary root architecture influencing the expression of auxin- and JA-responsive genes, and cell division. Lateral root formation was regulated by 4-methyl-2-pentanone, 3-methyl-1-butanol, 1-nonanol and ethyl isovalerate suggesting a participation via JA signalling. Our study revealed the differential emission of volatiles by PGPR vs non-PGPR from avocado trees and provides a general view about the mechanisms by which those volatiles influence plant growth and development. Rhizobacteria strains and mVOCs here reported are promising for improvement the growth and productivity of avocado crop.

This chapter provides a historical overview of the politics of Nicaragua’s domestic resource mobilization for social development. Focusing on the quality of state-society relations, the chapter analyses strategies for development financing and the social tensions and contradictions that emerged during the Somoza dictatorship (1936–1979), the Sandinista revolution (1979–1989), neoliberal adjustment (1990–2006) and the current Ortega regime (2007–present). Case studies of tax reform negotiations for a more equitable tax system, the challenges and opportunities of Venezuelan Aid (Bolivarian Alternative for the Americas—ALBA), grassroots contestation of mining in Rancho Grande, and health sector financing and institution building contribute empirical evidence to the analysis. The chapter argues that social services increase and expand when states prevent elite capture of resources and democratization processes are strengthened.

The bacterial and fungal community involved in ambrosia beetle fungiculture remains poorly studied compared to the famous fungus-farming ants and termites. Here we studied microbial community dynamics of laboratory nests, adults, and brood during the life cycle of the sugarcane shot hole borer, Xyleborus affinis. We identified a total of 40 fungal and 428 bacterial operational taxonomic units (OTUs), from which only five fungi (a Raffaelea fungus and four ascomycete yeasts) and four bacterial genera (Stenotrophomonas, Enterobacter, Burkholderia, and Ochrobactrum) can be considered the core community playing the most relevant symbiotic role. Both the fungal and bacterial populations varied significantly during the beetle’s life cycle. While the ascomycete yeasts were the main colonizers of the gallery early on, the Raffaelea and other filamentous fungi appeared after day 10, at the time when larval hatching happened. Regarding bacteria, Stenotrophomonas and Enterobacter dominated overall but decreased in foundresses and brood with age. Finally, inferred analyses of the putative metabolic capabilities of the bacterial microbiome revealed that they are involved in (i) degradation of fungal and plant polymers, (ii) fixation of atmospheric nitrogen, and (iii) essential amino acid, cofactor, and vitamin provisioning. Overall, our results suggest that yeasts and bacteria are more strongly involved in supporting the beetle-fungus farming symbiosis than previously thought., Research reported in this publication was supported by CONACyT-FORDECYT number 292399, Spanish Ministry of Economy and Competitiveness under award numbers SAF2015-65878-R and PGC2018-099344-B-I00, cofinanced by the European Regional Development Fund (ERDF), and from Generalitat Valenciana (project Prometeo/2018/A133). P.H.W.B. was supported by the German Research Foundation (DFG Emmy Noether grant BI 1956/1-1).

Background In Mexico, coffee leaf rust (CLR) is the main disease that affects the Arabica coffee crop. In this study, the local response of two Mexican cultivars of Coffea arabica (Oro Azteca and Garnica) in the early stages of Hemileia vastatrix infection was evaluated. Methods We quantified the development of fungal structures in locally-infected leaf disks from both cultivars, using qRT-PCR to measure the relative expression of two pathogenesis recognition genes (CaNDR1 and CaNBS-LRR) and three genes associated with the salicylic acid (SA)-related pathway (CaNPR1, CaPR1, and CaPR5). Results Resistance of the cv. Oro Azteca was significantly higher than that of the cv. Garnica, with 8.2% and 53.3% haustorial detection, respectively. In addition, the non-race specific disease resistance gene (CaNDR1), a key gene for the pathogen recognition, as well as the genes associated with SA, CaNPR1, CaPR1, and CaPR5, presented an increased expression in response to infection by H. vastatrix in cv. Oro Azteca if comparing with cv. Garnica. Our results suggest that Oro Azteca’s defense mechanisms could involve early recognition of CLR by NDR1 and the subsequent activation of the SA signaling pathway.

ZnO, Cu, and Cu2O/Cu nanoparticles (NPs) were evaluated for the degradation of methylene blue (MB) by three different approaches, namely, photocatalysis, Fenton-like, and photo-Fenton. Additionally, the in-vitro antifungal activity of the NPs was evaluated against three different phytopathogenic fungi, namely, Fusarium oxysporum, Fusarium solani, and Colletotrichum gloeosporioides. We found that the photo-Fenton degradation of MB was very similar for the three evaluated materials, with a degradation higher than 99.5%. On the other hand, the Cu2O/Cu-NPs was the best material for both the Fenton-like process and as an antifungal. Cu2O/Cu-NPs showed inhibition of radial growth as high as 96% for F. oxysporum, 74% for F. solani, 89% for C. gloeosporioides. Here we show that one nanomaterial could be effective for both degradation of dyes and pest control.

Pisolithus tinctorius is an ectomycorrhizal fungus that has been used worldwide as an inoculant to promote the growth and health of plant roots of forest importance. P. tinctorius has capacity to form symbiosis which mycorrhizal plants through the production of phytohormones, indole-3-acetic acid (IAA) the main auxin produced by these ectomycorrhizal fungi modulating root system architecture by inducing lateral root formation and root hair elongation in host plants of tree forest. However, the inoculant or compounds produced by P. tinctorius have not been evaluated in non-mycorrhizal plants. In the present study, we evaluated the effects of crude extracts of the P. tinctorius (CEPt) culture supernatant using Arabidopsis thaliana as plant model system to elucidate the molecular mechanisms of plant growth in non-host plant. Our results suggest that the crude extract of the supernatant produced by P. tinctorius has the ability to induce plant growth and root system architecture in Arabidopsis seedlings through the production of compounds with auxin-like activity, inducing the expression of DR5::uidA and BA3::uidA Arabidopsis line reporter of auxin responses and required an intact auxin signaling pathway, to modulate the plant growth in Arabidopsis seedlings.

The potato cyst nematode is a major threat to potato production worldwide. In the highlands of Veracruz State, Mexico, potato cultivation has been the main economic activity during the last seven decades, and it is severely affected by the high abundance of Globodera rostochiensis. In this study, the field efficacy of chemical nematicides, nematophagous fungi, crop rotation and the combination of the latter two strategies were assessed on G. rostochiensis abundance while also considering their effects on the free-living nematode community. Integrated management combining the use of nematophagous fungi and crop rotation was the most effective strategy for decreasing the abundance of G. rostochiensis (up to 13%). Additionally, high diversity, low disturbance, and a slightly higher structure were observed in the nematode community in the integrated management treatment. Although nematophagous fungi and crop rotation separately were less effective in reducing G. rostochiensis abundance (41% and 23%, r...

Plants interact with a great variety of microorganisms that inhabit the rhizosphere or the epiphytic and endophytic phyllosphere and that play critical roles in plant growth as well as the biocontrol of phytopathogens and insect pests. Avocado fruit damage caused by the thrips species Scirtothrips perseae leads to economic losses of 12-51% in many countries. In this study, a screening of bacteria associated with the rhizosphere or endophytic phyllosphere of avocado roots was performed to identify bacterial isolates with plant growth-promoting activity in vitro assays with Arabidopsis seedlings and to assess the biocontrol activity of the isolates against Scirtothrips perseae. The isolates with beneficial, pathogenic and/or neutral effects on Arabidopsis seedlings were identified. The plant growth-promoting bacteria were clustered in two different groups (G1 and G3B) based on their effects on root architecture and auxin responses, particularly bacteria of the Pseudomonas genus (MRf4-2, MRf4-4 and TRf2-7) and one Serratia sp. (TS3-6). Twenty strains were selected based on their plant growth promotion characteristics to evaluate their potential as thrips biocontrol agents. Analyzing the biocontrol activity of S. perseae, it was identified that Chryseobacterium sp. shows an entomopathogenic effect on avocado thrips survival. Through the metabolic profiling of compounds produced by bacteria with plant growth promotion activity, bioactive cyclodipeptides (CDPs) that could be responsible for the plant growth-promoting activity in Arabidopsis were identified in Pseudomonas, Serratia and Stenotrophomonas. This study unravels the diversity of bacteria from the avocado rhizosphere and highlights the potential of a unique isolate to achieve the biocontrol of S. perseae.

Coffee corky-root disease causes serious damages to coffee crop and is linked to combined infection of Fusarium spp. and root-knot nematodes Meloidogyne spp. In this study, 70 Fusarium isolates were collected from both roots of healthy coffee plants and with corky-root disease symptoms. A phylogenetic analysis, and the detection of pathogenicity SIX genes and toxigenicity Fum genes was performed for 59 F. oxysporum and 11 F. solani isolates. Based on the molecular characterization, seven F. oxysporum and three F. solani isolates were assessed for their pathogenicity on coffee seedlings under optimal watering and water stress miming root-knot nematode effect on plants. Our results revealed that a drastic increment of plant colonization capacity and pathogenicity on coffee plants of some Fusarium isolates was caused by water stress. The pathogenicity on coffee of F. solani linked to coffee corky-root disease and the presence of SIX genes in this species were demonstrated for the first time. Our study provides evidence for understanding the pathogenic basis of F. oxysporum and F. solani isolates on coffee and revealed the presence of SIX and Fum genes as one of their pathogenicity-related mechanisms. We also highlight the relevance of chlorophyll, a fluorescence as an early and high-throughput phenotyping tool in Fusarium pathogenicity studies on coffee.

Both the effectiveness of copper nanoparticles (Cu-NPs) as a treatment for Fusarium wilt and the role of Cu-NPs in promoting tomato plant growth were studied. First, we evaluated the in vitro antifungal activity of Cu-NPs at different concentrations (0.1, 0.25, 0.5, 0.75, and 1.0 mg/mL) against Fusarium oxysporum f. sp. lycopersici (FOL). A strong inhibitory effect on mycelial FOL growth (67.3%) was observed with 0.5 mg/mL Cu-NPs compared to a commercial fungicide based on copper hydroxide, whose inhibitory effect was only 15.6%. Next, in in vivo experiments at the same concentration, Cu-NPs significantly diminished the symptoms of Fusarium wilt by 68 and 66.5% for incidence and severity, respectively. Moreover, the treatments with Cu-NPs increased the growth of tomato plants and particularly raised the chlorophyll content (from 19.3 to 28.6%). This is because Cu-NPs effectively deliver copper as a micronutrient for the plants, while the uncontrolled uptake of copper ions from the commercial fungicide (copper hydroxide) inhibits the healthy development of plants. Importantly, despite the principal function of Cu-NPs as a fungicide, Cu-NPs may be applied as fertilizer for tomato plants. Thus, the application of Cu-NPs effectively treats Fusarium wilt while promoting the growth of tomato plants. Therefore, these results suggest that copper nanomaterials may be used as both a source of micronutrients in cases of soil copper deficiency and as a fungicide. In terms of sustainability, this multifunctionality has the potential to positively impact the environment.

Monitoring is a key activity in management of pests such as phytophagous thrips (Thysanoptera). Sampling thrips on medium and tall trees has been difficult without appropriate tools. The study compared the number of thrips collected and collection time by a new method of top-canopy spraying with an original device that is more efficient and practical versus two other collection methods, beating and conventional spraying. Design, construction, and validation of the thrips-collecting device for sampling top strata of orchard trees such as avocado (Persea americana Mill.) are presented. Similar numbers of thrips were collected with conventional methods and the new collecting device. Average collection time between spraying and beating methods was reduced 48 and 67%, respectively. Using the device to collect thrips at top strata of trees resulted in less risk to collectors in an effortless way. Use of the thrips-collecting device for the top part of the canopy and the conventional spraying method for the lower part could improve detection of phytophagous thrips, and might enhance efficiency of control methods by implementing them in a timely way.

Different copper based-materials have been used for controlling some fungal and bacterial pathogens. However, the antifungal activity of the copper-based materials depends on different parameters, such as the crystal phase, synthesis route, and size of the particles. Herein a facile route synthesis method of Cu/CuxO-NPs was achieved through the aqueous phase. The influence of NaBH4 concentration on the phase composition was studied. The synthesized Cu/CuxO-NPs were characterized by X-Ray diffraction (XRD), Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and dynamic light scattering. Five Cu/CuxO-NPs with different phase composition and nanoparticle size were obtained. The antifungal activity of the synthesized Cu/CuxO-NPs was studied in vitro against Fusarium oxysporum. The results indicate that a high percent of inhibition of radial growth (IGR) was obtained with NPs, which have a higher proportion of Cu2O phase and relatively smaller size particles. Furthermore, hypha morphology, membrane damage and production of reactive oxygen species (ROS) was evaluated with SEM and confocal microscopy.

We evaluated the nematicidal potential and phosphate solubilization ability of the fungal species Geomyces pannorum and Paecilomyces carneus, which are associated with the potato cyst nematode Globodera rostochiensis. In a broth medium containing calcium phosphate, the two fungi solubilized between 67%-96% of the insoluble phosphorus that was present in the medium, and in a broth medium containing iron phosphate, the phosphorus that was solubilized by the two fungi ranged between 2%-13%. In a greenhouse experiment, G. pannorum and P. carneus were applied to soil that was naturally infested with G. rostochiensis and planted with Avena sativa. The fungi increased the available phosphorus in the soil by more than 30%, and Paecilomyces carneus also reduced the nematode population by 71%. This study is the first to report on the ability of G. pannorum and P. carneus to increase the available phosphorus in the soil, suggesting that these fungal species may have potential uses in agricultural soils with insoluble phosphorus. Moreover, this study provides a new alternative that contributes to the sustainable management of crops with bio-agents that have dual activity; they increase the available phosphorus in the soil and mitigate plant parasitic nematodes.

Fungi associated with the coffee berry borer, Hypothenemus hampei (Ferrari), are determined and galleries in coffee fruit, Coffea arabica L., are described. In total, 13 fungus species were found to be associated with the coffee berry borer and its galleries. These fungi were divided into four functional groups: 1) saprobic fungi that the borer uses as food: Fusarium heterosporum Nees ex Fries, Cladosporium sp., Cladosporium oxysporum Berkeley & Curtis, and Penicillium echinulatum Fassatiova; 2) saprobic fungi that degrade borer feces: Aspergillus flavus Link, Aspergillus niger Tieghem, Mucor luteus Linnemann, Penicillium sp. 1, Humicola grisea Traaen, and Gliocladium penicilloides Corda; 3) fungi that are coffee parasites: Fusarium oxysporum Schlechetend and Fusarium solani (Martius) Saccardo; and 4) the entomopathogenic fungus Beauveria bassiana (Balsamo-Crivelli) Vuillemin. The same fungi were found on and inside the insect as well as in galleries and were components of the insect’s diet. Apparent interference of B. bassiana by F. solani was observed.

International audience; A major issue of potato cultivation in temperate zones is the potato cyst nematode Globodera rostochiensis. Population density of G. rostochiensis is high in Mexican potato fields. Control currently consists of the inefficient application of high doses of chemical nematicides. We evaluated the population density of G. rostochiensis in potato production plots in central Veracruz, Mexico. Plots were treated with the biocontrol agent Paecilomyces sp. and rotation with two different leguminous crop plants, Pisum sativum and Vicia faba. A random block experimental design was used with four different treatments over two crop cycles: (1) biological control with crop rotation, (2) crop rotation only, (3) biological control applied to soil left in fallow, and (4) soil left in fallow only. We measured the number and content of cysts, and the number of J2 juveniles of G. rostochiensis in the soil. We then estimated the infestation level in soil and the multiplication rate (Pf/Pi). The number of free-living nematodes was also quantified. Results show that the highest mitigation of G. rostochiensis was observed for the biological control rotation, with 89.2 % reduction, and for the biological control fallow treatments with 84.4 % reduction. In rotation plots, infestation level decreased by 30.7 %. In the biological control rotation and biological control fallow treatments, the Pf/Pi was 0.1 and 0.15, respectively. The highest Pf/Pi of 0.93 was found in the fallow plots. The biological control agent did not significantly affect the free-living nematode populations. In this study, the nematophagous fungus Paecilomyces sp. was used for the first time to efficiently reduce the population of G. rostochiensis in two crop cycles.

Debido a la alta densidad del nematodo dorado de la papa Globodera rostochiensis en la zona montañosa del Cofre de Perote, en Veracruz, México, se han buscado hongos parásitos en los diferentes estadios de esta plaga. El objetivo del estudio fue aislar hongos asociados del segundo estadio juvenil (J2) de G. rostochiensis en predios de cultivo de papa en la región del Cofre de Perote, y de estos hongos evaluar la patogenicidad in vitro del hongo con mayor potencial nematófago sobre huevos y juveniles J1 y J2 de G. rostochiensis. Se extrajeron ejemplares J2 del nematodo dorado de 10 muestras de suelo (500 cc) mediante el método de Baerman; 300 J2 se colocaron individualmente en discos de 8 mm de agar con extracto de malta para favorecer el crecimiento de hongos. Se obtuvieron 16 cepas de hongos (5.3%) aislados de J2: Aureobasidium (3), Cladosporium (2), Fusarium (3), Pestalotiopsis (3), Penicillium (4) y Purpureocillium lilacinum (1). Este último fue seleccionado para estudiar el proceso de infección y evaluar su patogenicidad sobre huevos y juveniles J1 y J2 del nematodo dorado. La germinación de las esporas de P. lilacinum se observó a las 12 h de la inoculación, el desarrollo del micelio en el interior y exterior de los J2 a las 72 h y la formación de conidióforos a las 96 h.

We describe the traditional production system of the root of jalapa, Ipomoea purga, in Xico, Veracruz, Mexico. The results are based on open interviews with the producers to gather information on the development of this crop in the area, and observation of the production system. The production cycle is carried out between July and February. We found that seed scarification is the key to the success of the productive system, obtaining a maximum of 95% seed germination in eight days. This activity, as well as seed collection and the driving of stakes into the ground for plant support, requires a considerable input of man-power. It is an intensive farming process, the cultivated area per farmer varies between 300 m2 and 1000 m1, and the yield ranges between 1.5 and 2.7 tons per hectare of fresh roots; when dried they lose up to 75% of their weight. Smoke-dried roots are exported for sale.

La caña de azúcar (Saccharum officinarum) es un cultivo importante en el estado de Veracruz, México, su rendimiento ha disminuido en años recientes y una causa de la baja productividad podría ser la alta densidad de nemátodos fitoparásitos. El conocimiento de éstos y de los nemátodos de vida libre, así como la evaluación de sus densidades poblacionales, son importantes para determinar estrategias de control. Por tanto, el objetivo de este estudio fue identificar la nematofauna asociada a la rizósfera de caña de azúcar en seis predios de las zonas de abastecimiento de los ingenios La Gloria y El Modelo, en la región costa-centro del estado de Veracruz. Se usó un diseño completamente al azar para cuantificar el número de individuos por especie de nemátodo y por grupo trófico; además se estimó el índice de diversidad trófica y el índice de riqueza. El número de individuos por grupo trófico se analizó con un ANDEVA factorial, y los demás datos se analizaron con un ANDEVA de una vía. Se identificaron 12 morfotipos de nemátodos de los órdenes Tylenchida, Dorylaimida, Rhabditida y Aphelenchida. Los nemátodos fitófagos fueron: Criconemoides, Helicotylenchus, Longidoridae, Tylenchus, Xiphinema y los demás fueron nemátodos bacteriófagos, micófagos y omnívoro-predadores (Acrobeles, Aphelenchus, Aporcelaimellus, Aporcelaimidae, Cephalobidae, Cruznema, Thornenema). Los fitoparásitos más abundantes en promedio en los seis predios fueron Helicotylenchus (47+23 100 cm-3 de suelo) y Criconemoides (31+44 100 cm-3 de suelo). La abundancia de los nemátodos fitoparásitos no fue lo suficientemente elevada (50 100 cm-3 de suelo) para asociarla con la disminución del rendimiento en el cultivo de caña de azúcar.

Business and other non-state actors like non-governmental organizations (NGOs) and social movements have proliferated in the crafting of international trade regimes at the bilateral, regional and multilateral levels. In an increasingly technical, legalistic and complex international trade policymaking environment, expertise and financial resources take a leading role. These actors, however, differ in their degrees of access to knowledge and resources, and, ultimately, in the exercise of power.

Nematode species associated with the rhizosphere of Solanum tuberosum were identified and classified into trophic groups from soils highly infected by the golden potato cyst nematode (Globodera rostochiensis) in a single crop cycle in the producing zone on the Cofre de Perote, Veracruz, Mexico. Seven genera (Aphelenchoides, Aphelenchus, Crassolabium, Mesodorylaimus, Plectus and Steinernema) and 8 species (Aporcelaimellus obtusicaudatus, Ecumenicus monohystera, Acrobeles mariannae, Acrobeles singulus, Acrobeloides nanus, Cruznema tripartitum, Eucephalobus oxyuroides, and Globodera rostochiensis) were found in association with the rhizosphere of cultivated potatoes. Crassolabium sp. and E. monohystera are recorded for the first time in Mexico.

Los nematodos fitoparásitos constituyen uno de los principales problemas fitosanitarios que afectan el cultivo de plátano a nivel mundial. En México este frutal es uno de los principales productos agrícolas y en el estado de Veracruz, la zona más importante de producción se ubica en los municipios de Atzalan y Tlapacoyan. En algunos cultivos de plátano de estos municipios se han detectado plantas con lesiones y engrosamientos en la raíz, síntomas inducidos por nematodos. Con la finalidad de determinar que nematodos estaban asociados a esta sintomatología, se colectaron raí- ces en seis plantaciones de los municipios Atzalan y Tlapacoyan durante el mes de abril de 2014.

Se determinaron y clasificaron en grupos tróficos las especies de nematodos asociados a la rizosfera de Solanum tuberosum en suelos altamente infectados por el nematodo dorado de la papa (Globodera rostochiensis) en un ciclo de cultivo, en la zona productora del Cofre de Perote, Veracruz, México. Se identificaron 7 géneros (Aphelenchoides, Aphelenchus, Crassolabium, Mesodorylaimus, Plectus y Steinernema) y 8 especies (Aporcelaimellus obtusicaudatus, Ecumenicus monohystera, Acrobeles mariannae, Acrobeles singulus, Acrobeloides nanus, Cruznema tripartitum, Eucephalobus oxyuroides, y Globodera rostochiensis) en asociación con la rizosfera de papas cultivadas. Crassolabium sp. y E. monohystera se registran por primera vez para México.