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Meloidogyne enterolobii, the guava root-knot nematode, has emerged as a significant problem in tropical and subtropical regions across the continents. Along with Fusarium spp., this nematode plays a crucial role in causing guava decline. In the newer locations, M. enterolobii can parasitize on many crops like other root-knot nematodes, including crops carrying nematode-resistance genes. This article reviews the current state of knowledge on all aspects of M. enterolobii, with a special focus on its management strategies. [ABSTRACT FROM AUTHOR]

Meloidogyne enterolobii (Me) is an emerging root-knot nematode (RKN) and the most important worldwide for its high aggressiveness and increasing geographical distribution. In Mexico only in watermelon and tomato has been reported. Here we report the presence of this nematode in Jalapeño pepper collected in the state of Sinaloa. The morphological and morphometric characteristics of the second-stage juveniles and adult females were similar to those described for Me. DNA sequencing and alignment analysis (BLAST/GenBank) showed that the SCAR and rDNA IGS2 fragments had a 99 % of identity, with Me DNA sequences present in the database. The results obtained indicate that the RKN detected corresponds to M. enterolobii. To our knowledge, this is the first report of this nematode in chilli pepper in this region of Mexico, considered of major economic importance for the variety of vegetables grown and the extension of the area sown.

O objetivo deste trabalho foi identificar genótipos de alface, batata-doce, feijão, tomate e Capsicum resistentes ao nematoide Meloidogyne enterolobii (Syn. M. mayaguensis) e classificá-los quanto ao grau de resistência. Foram avaliados: 10 genótipos de alface, 8 de batata-doce, 10 de feijão e feijão-vagem, 25 de Capsicum e 6 de tomate. Foram calculados o fator de reprodução e o índice de reprodução, e os genótipos foram classificados quanto ao grau de resistência ao nematoide. Foram observados níveis moderados de resistência na cultivar de feijão Aporé e nos acessos de pimenta, BGH-433 e BGH-4285, e de pimentão, PIM-031, PIX-022I-31-07-02 e PIX-022I-31-13-01. Todos os genótipos de tomate são suscetíveis a M. enterolobii. As cultivares de alface Julia, Hortência, Verônica, Grand Rapids e Babá de Verão, e os clones de batata-doce UFLA07-49 e UFLA07-53 são muito resistentes ao nematoide. A resistência a M. enterolobii aparentemente é mediada por genes diferentes dos que conferem resistência a outras espécies e raças de Meloidogyne.

Meloidogyne enterolobii (= M. mayaguensis) has been reported as a potential threat to tomato (Solanum lycopersicum) and pepper (Capsicum spp.) crops in tropical and subtropical areas. Of particular concern with this nematode is its ability to overcome the resistance mediated by the tomato Mi-1 gene as well as by some of the Me genes in Capsicum. In the present work, we report for the first time the occurence of M. enterolobii infecting Capsicum annuum plants carrying the Me1 and Me3/Me7 genes under plastic house systems in Brasília-DF (Central Brazil). Plants of the commercial rootstock hybrid 'Snooker' (a pyramid of the genes Me1 and Me3/ Me7) infected by M. enterolobii (esterase phynotype M2) exhibited overall yellowing, severe wilt symptoms, premature defoliation, and root rot accompanied by profuse root galling. To our knowledge, this is the first report of M. enterolobii infection in root-knot resistant Capsicum rootstocks in Central Brazil, thus expanding the geographical distribution of this pathogen in this host species. [ABSTRACT FROM AUTHOR]

Etude de trois souches d'Arthrobotrys oligospora : Caractérisation biologique et effets sur Meloidogyne mayaguensis parasite de la tomate au Sénégal. Three strains (ORS 18690 S2, ORS 18691 S6 and ORS 18693 S5) of the nematophagous fungus Arthrobotrys oligospora have been isolated in Senegal for the first time. In vitro, two strains (ORS 18690 S2 and ORS 18693 S5) of them trapped 100 % and the other (ORS 18691 S5) 80 %> of 7-day-old juvenile Meloidogyne mayaguensis within 48h. Optimal growth occured at 25-30°C and at a pH 5.6, but salinity inhibited development. In order to test the ability of fungi to control M. mayaguensis in pots on tomato, the fungus was incorporated into compost blocks or in vermiculite before sowing or subsequent transplanting. In pot experiments both strains reduced nematode populations ans stimulated seedling growth. However, these effects were higher in compost blocks than in vermiculite.

Este é o primeiro relato de M. mayaguensis em Passiflora misera. Além deste fitonematóide, foram detectados Helicotylenchus sp. e Rotylenchulus sp. nesta espécie

Os nematóides de galhas, do gênero Meloidogyne, estão entre as pragas que mais afetam as culturas de interesse agronômico no Brasil. Espécies de nematóide das galhas relatados, até então, associadas à Passiflora no Brasil, são: Meloidogyne arenaria; M. incognita e M. javanica. Os fitonematóides do gênero Meloidogyne, principalmente M. incognita e M. javanica, têm ampla gama de hospedeiros entre as plantas invasoras e plantas comercialmente cultivadas e, estão entre os de maior importância econômica para diversas frutíferas brasileiras e flores ornamentais. Passiflora misera Kunth é uma espécie de pequeno porte, com flores brancas e folhas ornamentais, e que apresentava sintomas como folhas amareladas e muitas galhas nas raízes, não respondendo á adubação. Amostras de solo e raízes de P. misera foram encaminhadas para o Laboratório de Nematologia da Faculdade de Ciências Agrárias e Ambientais de Jaboticabal, SP - Universidade Estadual Paulista (UNESP/FCAV), das quais 100 cc de solo foram utilizados para extração de fitonematóides através de processamento de centrifugação e 10 g de raiz foram processadas em liquidificador por 20 seg associada à flotação centrífuga. Foram detectadas altas populações de Meloidogyne mayaguensis. Em amostras de solo foram detectados 280 nematóides, e em raízes, 2.560 nematóides e 20.480 ovos. Este fitonematóide tem sido relatado parasitando cultura da goiaba, pimentão, pimenta, melão, café, fumo, tomate, entre outros. Este é o primeiro relato de M. mayaguensis em Passiflora misera. Além deste fitonematóide, foram detectados Helicotylenchus sp. e Rotylenchulus sp. nesta espécie.

Meloidogyne mayaguensis Rammah y Hirschmann, is an important pest in tropical and subtropical countries, because it affects in natural way more than 30 different species like guava (Psidium guajava), coffee (Coffea spp.), vegetables, ornamental plants and weeds. Its distribution has been very fast due to anthropogenic factors, and the highest concern about this species is its capacity to infest and reproduce on resistant plants to Meloidogyne spp. This species has a high variability in its perineal pattern morphology; thus the use of complementary elements like the offered by esterase profile is recommended. This specie has been found in mixed population with Meloidogyne incognita, Meloidogyne arenaria and Meloidogyne javanica, making more complex its diagnosis and management. Among the measurements to diminish its negative effect are the implementation of internal quarantine measures and the use of Cadusafos and Abermectine with variable results. In the same way, different research teams from Africa and America have evaluated extracts from Crotalaria spp., biological control agents (Arthrobotrys spp.), among other tactics. M. mayaguensis has been considered one of the most dangerous species of this genus. Its detection, right identification and contention in the areas in which it is found constitute one of the most important challenges for the sanitary authorities in the countries when the species has been reported. The opportune information and the effective training of the staff involved in the phytosanitary area represent a vital element for facing this emergent pest. [ABSTRACT FROM AUTHOR]

The in vitro paralysis of second-stage juveniles of Meloidogyne incognita, M. javanica and M. mayaguensis by aqueous extracts of 15 West African Crotalaria species was analysed. A multivariate analysis distinguished four groups, based on their nematostatic activity: i) C. glaucoides extracts were not active; ii) the root extracts from C. goreensis, C. lathyroides and C. perrottetii were more active than the shoot extracts; iii) the shoot extracts from C. comosa and C. cylindrocarpa were more active than the root extracts; iv) both shoot and root extracts of C. atrorubens, C. barkae, C. grantiana, C. hyssopifolia, C. pallida, C. podocarpa, C. retusa, C. senegalensis and C. sphaerocarpa have nematostatic effects depending on either the Crotalaria species or plant tissue from which the extracts were derived. However, considering the greater biomass contribution of the leaves and stems compared to the roots when the plants are used as green manure, C. barkae, C. grantiana, C. pallida and C. podocarpa are the most efficient Crotalaria species, whatever the Meloidogyne species targeted. [ABSTRACT FROM AUTHOR]