First Report of Meloidogyne javanica Parasitizing Duboisia sp. in Paraná State, Brazil.

Duboisia sp. is a small tree belonging to the family Solanaceae originating from the rainforest areas of the eastern coast of Australia. Dried leaves are used for the extraction of pharmaceutical alkaloids, making this a commercially viable crop. The root-knot nematode Meloidogyne incognita has been reported parasitizing Duboisia myoporoides (5); however, no information of other root-knot nematode species associated with this plant was found. Duboisia sp. is cultivated at Solana Farm, near Arapongas (23°25'08″ S, 51°25'26″ W), Paraná State, Brazil. During the renovation of a production field in this municipality, galled roots were observed on plants and samples were submitted to the Nematology Laboratory at Instituto Agronômico do Paraná, IAPAR, on December 2013. Plants did not exhibit any above-ground symptoms. The specimens were identified through perineal patterns and esterase phenotypes of 20 adult females extracted from dissected roots (2,3) and morphometrics of 10 second-stage juveniles extracted from roots using the blender-sieving method (1). Morphological characteristics were consistent with those described for M. javanica (4). Females had rounded perineal patterns with low, trapezoid shape dorsal arch, striae smooth interrupted by a pair of incisures on both sides, corresponding to lateral fields, clearly demarcated from striae by more or less parallel lines, tail whorl often distinct (4). The juvenile mean body length was 459.9 ± 28.7 µm and tail length averaged 51.6 ± 5.1 µm, with 10 to 16 µm long hyaline region and finely rounded tail tip (4). Results from the esterase electrophoresis were typical of M. javanica (2) with the J3 (Rm = 1.0, 1.3, and 1.4) phenotype being obtained. To our knowledge, this is the first report of M. javanica on Duboisia sp. in Brazil. This finding has great importance for Brazilian production since this nematode may damage plants, reduce yields, and control of this nematode on Duboisia sp. is difficult (5). Additional work is necessary in order to elucidate the losses caused by M. javanica on Duboisia sp. References: (1) J. I. Bonetti and S. Ferraz. Fitopatol. Bras. 6:533, 1981. (2) P. R. Esbenshade and A. C. Triantaphyllou. J. Nematol. 22:10, 1990. (3) K. M. Hartman and J. N. Sasser. Page 115 in: An Advanced Treatise on Meloidogyne. Volume II Methodology. K. R. Barker et al., eds. North Carolina State University Graphics, Raleigh, 1985. (4) D. J. Hunt and Z. A. Handoo. Page 55 in: Root-Knot Nematodes. R. N. Perry et al., eds. CABI International, Wallingford, UK, 2010. (5) A. M. Mello et al. Nematol. Bras. 22(2):12, 1998.

First Report of the Root Knot Nematode, Meloidogyne inornata, on Common Bean in Paraná State, Brazil.

Common bean (Phaseolus vulgaris F.) is one of the most important crops in Paraná State, which is responsible for almost 10% of the Brazilian production (4). Root knot nematodes, Meloidogyne spp., are common parasites of this crop worldwide, but damage caused by Meloidogyne inornata has not been reported. During a survey of nematode species present on common bean fields in Paraná State, Brazil, galled root samples of cultivars Tuiuiú and Eldorado were submitted, in June 2012, in the Nematology Laboratory from IAPAR, collected in the municipalities of Araucária (25°35'34″S, 49°24'36″W) and Santana do Itararé (23°45'18″S, 49°37'44″W). Plants did not exhibit any above-ground symptoms. The specimens were identified through perineal patterns and esterase phenotypes of 20 adult females extracted from dissected roots (2,3). The population densities observed in the samples were 140 and 700 J2 and eggs per gram of roots, respectively, for both samples. Characteristics were consistent with those described for M. inornata. For example, perineal patterns of M. inornata showed a high dorsal arch, with smooth to wavy striae, similar to those of M. incognita; but no punctate markings between anus and tail terminus were observed. However, from the esterase electrophoresis we obtained the I3 (Rm = 0.83, 1.15, and 1.32) phenotype, typical of M. inornata, a species-specific phenotype used to differentiate this species from M. incognita (1). Moreover, the excretory pore of adult females was located 32.1 (± 5.4) µm from the anterior end, consistent with the M. inornata description (25 to 53 µm) (1). To the best of our knowledge, this is the first report of M. inornata parasitizing common bean roots. This finding has great importance for Brazilian agriculture, since this nematode may damage common bean plants and become an additional problem for this crop. Additional work is necessary in order to elucidate the losses caused by M. inornata on common bean. References: (1) R. M. D. G. Carneiro et al. Nematology 10:123, 2008. (2) P. R. Esbenshade and A. C. Triantaphyllou J. Nematol. 22:10, 1990. (3) K. M. Hartman and J. N. Sasser. Page 115 in: An Advanced Treatise on Meloidogyne, Volume II Methodology. K. R. Barker et al., eds. Raleigh: North Carolina State University Graphics, 1985. (4) MAPA. Feijão, Ministério da Agricultura, Brasil. Retrieved from http://www.agricultura.gov.br/vegetal/culturas/feijao September 05, 2012.

Root-Knot Disease Caused by Meloidogyne arenaria and M. javanica in Teak in São Paulo State, Brazil.

Teak (Tectona grandis Linn. F.) is one of the most important forest crops in Brazil, occupying areas in different regions, such as Goiás, Mato Grosso, Paraná, and São Paulo states. Teak wood is used for many purposes such as shipbuilding, rolling and plywood, firewood, and charcoal. In May 2011, teak symptomatic feeder root samples, exhibiting inconspicuous, small galls, were collected in the municipality of Piracicaba, São Paulo State, Brazil (22°41'46.90″S, 47°38'36.84″W). Specimens were identified through perineal patterns and esterase phenotypes of 20 adult females (1,2). Perineal patterns and esterase phenotypes were consistent with those described for Meloidogyne arenaria (Neal, 1889) Chitwood, 1949 and M. javanica (Treub, 1885) Chitwood, 1949. Perineal patterns of M. arenaria showed a low dorsal arch, compressed dorsolaterally, with lateral field marked by some forked and broken striae; no punctate markings between anus and tail terminus were observed. Perineal patterns of M. javanica were rounded, with low dorsal arch, striae smooth, lateral field distinct, clearly demarcated from striae by parallel lines. From the esterase electrophoresis we obtained A2 (Rm:1.2;1.3) and J3 (Rm:1.0;1.25;1.4) phenotypes, typical from M. arenaria and M. javanica, respectively. To our knowledge, this is the first report of M. arenaria parasitizing teak roots in Brazil and elsewhere (new host) and the first report of M. javanica infecting teak in the State of São Paulo. Previously, M. javanica was reported to be infecting teak-growing areas in the State of Mato Grosso (3). This finding has a great importance, not only by the inclusion of these parasites in teak pathological scenario, but also for predicting possible damage in plant species used in teak-based intercropping systems. References: (1) P. R. Esbenshade and A. C. Triantaphyllou. J. Nematol. 22:10, 1990. (2) K. M. Hartman and J. N. Sasser. 1985. Page 115 in: An Advanced Treatise on Meloidogyne. Volume II, Methodology. K. R. Barker et al., eds. North Carolina State University Graphics, Raleigh,1985. (3) R. A. Silva et al. Nematol. Bras. 27:261, 2003.

Pequi is a Host for Pratylenchus zeae in the Brazilian Cerrado Region.

The Brazilian Cerrado Region has many natural resources that have high social economic interest. Pequi (Caryocar brasiliense Camb.), a native species from that area, has an edible fruit, which is highly appreciated by the local population, and also a high-quality wood. In January 2010, pequi root samples were collected near the municipality of Rio Verde, Goiás State, Brazil (17°49'25.76″S, 51°02'10.06″W). Roots were washed with tapwater, dried on absorbent paper, cut in 1-cm2 pieces, and processed for nematode extraction by the blender centrifugal flotation method (2). The specimens were identified by morphological and morphometrical characteristics of six adult females mounted in formaldehyde temporary slides (1). Morphological characters used for identification included female body, stylet, pharyngeal overlapping, pharynges, postvulval uterine sac, tail lengths, stylet knobs, number of labial rings, vulva position in relation to body length, body diameters (high body, vulval, and anus region), and the de Man's ratios (a, b, b', c, and c'). Characters measured were consistent with those described for Pratylenchus zeae Graham, 1951 (1); the labial region showed three annuli, stylet was 14.83 (±0.93) µm long, with broad, anteriorly flattened basal knobs. Vulva position was 71.66% (±0.98) of body length and spermatheca was round, small, and without sperm (males were not found). Postvulval uterine sac was short (31.3 ± 4.03 µm) and tail (26.6 ± 3.61 µm) was conoid, pointed, and unstriated. Pharyngeal overlapping length was 30.5 (±6.5) µm; pharynges were 150.83 (± 28.16) µm long. The de Man's ratios obtained were: a = 24.26 ± 2.31; b = 3.89 ± 0.69; b' = 3.08 ± 0.48; c = 17.17 ± 1.47; and c' = 2.25 ± 0.19. To our knowledge, this is the first report of P. zeae infecting pequi. It is difficult to determine the economic importance of this nematode parasite to pequi production since pequi is not yet a commercial crop in Brazil. This finding, however, has long term importance because researchers have been developing improved cultivars by combining favorable agronomic characteristics with high oilseed content for biofuel production. If these are commercialized, P. zeae could become an important pathogen in pequi plantings. References: (1) P. Castillo and N. Vovlas. Pratylenchus (Nematoda: Pratylenchidae): Diagnosis, Biology, Pathogenicity and Management. Koninklijke Brill NV, Leiden, the Netherlands, 2007. (2) W. A. Coolen and C. J. D'Herde. A Method for the Quantiative Extraction of Nematodes from Plant Tissue. State Agric. Entomol. Res. Stn. Ghent, Belgium, 1972.