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A survey of entomopathogenic nematodes was conducted in sugar cane crops in a total of 14 soils, and positive results were obtained for strain MC5-2014 in the municipality of Tepalcingo, Morelos, in soil with a sandy loam texture and a pH of 6.4. Species determination was performed via morphological and morphometric techniques by searching for a tubular stoma with a swollen cylindrical pharyngeal body and a metacorpus in the basal part. The range of body length (L) was 750 to 1200 μm in females and 720 to 910 μm in males, while the corresponding maximum widths (W) of the body were 30 to 60 μm and 20 to 30 μm, respectively. Males exhibited bursa with a 1 + 1 + 3 + 3 distribution of papillae, and females exhibited a vulva located at the mid-body. For molecular identification, the ITS region of ribosomal DNA was used. Virulence tests (LC50) were conducted with Galleria mellonella, and a value of 4.732 was obtained for infective juveniles (IJs). Taking taxonomic and molecular characteristics into account, the isolate was determined to be Oscheius myriophila. The isolation of this strain represents the first geographic report of O. myriophila in Mexico, and it should be noted that the cultivation of sugar cane occurs with constant application of insecticides, herbicides, fungicides, and fertilizers as well as harvesting activities such as burning of the crop for harvest. The O. myriophila isolate has the potential to be used in the future as a method of biological control in our country. A survey of entomopathogenic nematodes was conducted in sugar cane crops in a total of 14 soils, and positive results were obtained for strain MC5-2014 in the municipality of Tepalcingo, Morelos, in soil with a sandy loam texture and a pH of 6.4. Species determination was performed via morphological and morphometric techniques by searching for a tubular stoma with a swollen cylindrical pharyngeal body and a metacorpus in the basal part. The range of body length (L) was 750 to 1200 μm in females and 720 to 910 μm in males, while the corresponding maximum widths (W) of the body were 30 to 60 μm and 20 to 30 μm, respectively. Males exhibited bursa with a 1 + 1 + 3 + 3 distribution of papillae, and females exhibited a vulva located at the mid-body. For molecular identification, the ITS region of ribosomal DNA was used. Virulence tests (LC50) were conducted with Galleria mellonella, and a value of 4.732 was obtained for infective juveniles (IJs). Taking taxonomic and molecular characteristics into account, the isolate was determined to be Oscheius myriophila. The isolation of this strain represents the first geographic report of O. myriophila in Mexico, and it should be noted that the cultivation of sugar cane occurs with constant application of insecticides, herbicides, fungicides, and fertilizers as well as harvesting activities such as burning of the crop for harvest. The O. myriophila isolate has the potential to be used in the future as a method of biological control in our country.

During a survey of plant parasitic nematodes in 2019, at Gansu Province, China, the stunt nematode Tylenchorhynchus zeae was found parasitizing corn seedlings. Females, males and juveniles of T. zeae were observed on soil and roots samples of corn after processing and extraction. This population of stunt nematodes was identified based on morphological and by sequencing the ITS1 region of rDNA and D2/D3 fragments of the 28 S rRNA. The ITS1 and the D2/D3 sequences of this population, shared 99.00 to 99.05% and 99.43 to 99.73% of similarity with sequences corresponding to T. zeae in GenBank, respectively. This is the first report of T. zeae infecting corn in Gansu Province, northwest China.

In 2016, “Tifdwarf” hybrid bermudagrass (Cynodon dactylon (L) Pers. × C. transvaalensis Burtt-Davy) grown on a golf green built to the United States Golf Association recommendations in Barbados started to show irregular significant chlorotic patches followed by gradual thinning and decline of turfgrass. A survey was conducted in May 2016 to determine the presence of plant-parasitic nematodes. The results revealed the presence of the plant-parasitic sting nematode Belonolaimus longicaudatus. To our knowledge, this is the first report of B. longicaudatus associated with bermudagrass in Barbados.

Two populations of a Butlerius species were recovered from compost in two gardens in Potchefstroom, North-West Province, South Africa. Although the genus has previously been reported from South Africa, no species of the genus has ever been identified in the country. Based on morphological, morphometric, and molecular studies, the specimens were identified as Butlerius butleri and are herein reported for the first time from South Africa. The South African specimens are 1,082 to 1,423 µm long, a = 40.8 to 47.6; b = 4.7 to 5.8; c = 4.0 to 6.0; c′ = 117 to 16.3; V = 44 to 47%. Cuticle with evenly spaced punctations. Reproductive system didelphic, amphidelphic, both branches equal in length. Four large glands opening into proximal part of uterus. Males with prominent sphincter present in mid-region of vas deferens. Spicules 36 to 43 μm long, gubernaculum 23 to 31 µm long, nine pairs of genital papillae, three pre-cloacal and six post-cloacal, formula: v1, v2, v3d/v4, ad, ph, v5, 6, 7, pd. The v5, 6, 7 clusters greatly separated, left subventral group at level of phasmid, right subventral group at level of posterior dorsal papilla. Although there were some differences, the South African populations of the species compare well to all know descriptions of the species. Phylogenetic analysis based on partial small subunit (SSU) rDNA sequences showed that both South African populations of B. butleri are in a maximally supported sister relation with an Iranian population of this species. Based on large subunit (LSU) rDNA sequences, the two populations of B. butleri clustered together in a well-supported clade.

In 2016, "Tifdwarf" hybrid bermudagrass (Cynodon dactylon (L) Pers. × C. transvaalensis Burtt-Davy) grown on a golf green built to the United States Golf Association recommendations in Barbados started to show irregular significant chlorotic patches followed by gradual thinning and decline of turfgrass. A survey was conducted in May 2016 to determine the presence of plant-parasitic nematodes. The results revealed the presence of the plant-parasitic sting nematode Belonolaimus longicaudatus. To our knowledge, this is the first report of B. longicaudatus associated with bermudagrass in Barbados. In 2016, “Tifdwarf” hybrid bermudagrass (Cynodon dactylon (L) Pers. × C. transvaalensis Burtt-Davy) grown on a golf green built to the United States Golf Association recommendations in Barbados started to show irregular significant chlorotic patches followed by gradual thinning and decline of turfgrass. A survey was conducted in May 2016 to determine the presence of plant-parasitic nematodes. The results revealed the presence of the plant-parasitic sting nematode Belonolaimus longicaudatus. To our knowledge, this is the first report of B. longicaudatus associated with bermudagrass in Barbados.

Humulus lupulus (Cannabaceae), commonly referred to as hops, are perennial, herbaceous climbing plants, native to temperate northern climates. Hops are cultivated for their strobiles or cones, which are often used for flavoring and aroma in food, tea, and beer (Almaguer et al. 2014; Burgess 1964). Because of the high demand for hops from the micro-brewing industry in the Tampa-St. Petersburg area, it has recently been introduced in Florida. The crop grows rapidly in the early spring to late summer. Plants reach a mature height of 18-25 feet in one year and produce cones from mid-summer to early fall (Pearson, 2016). Hop rhizomes were planted in April 2016 at the Gulf Coast Research Station, Wimauma, Hillsborough Co., Florida, USA. In October 2016, several hop plants that exhibited yellowing leaves and stunted growth were uprooted and showed severe root galling (Figs.1;2). Rhizosphere soil samples were collected for nematode extraction and showed high numbers of root-knot nematode second-stage juveniles (J2) (up to 1500 J2/ 200cm3 soil). Heavily galled root samples were sent to the Florida Department of Agriculture and Consumer Services, Division of Plant Industry Nematology Laboratory in Gainesville, FL. Species identification was performed using morphological analyses of females perenal patterns (n=22), selected characters of second-stage juveniles (n=17), and isozyme phenotypes (esterase and malate dehydrogenase) of egg- laying females (n=26) extracted from the roots. Configuration of the perineal patterns, morphometrics of body, stylet and tail length of J2 and the esterase phenotype (EST= J3), which is species-specific and malate phenotype (MDH=N1), are consistente with those reported in the original descrition of M. javanica and many other populations of this nematode species collected in Florida and other countries (Brito et al., 2008; Cofcewick et al., 2005; Carneiro et al., 2004; Jepson, 1987; Esbenshade and Triantaphyllou, 1985). For molecular analyses, DNA was extracted from individual females and mitochondrial DNA was amplified with MORF (5?- ATC GGG GTT TAA TAA TGG G - 3?) and MTHIS (5? - AAA TTC AAT TGA AAT TAA TAG C -3?) primer set (Pagan et al., 2015; Stanton et al., 1997). A fragment of approximately 740 bp was produced, which has been reported for M. incognita and M. javanica found in Florida (Baidoo et al., 2016). To further confirm the species identification we use the speices-specific SCAR primer set Fjav (5 ?- GGT GCG CGA TTG AAC TGA GC - 3?) and Rjav (5? - CAG GCC CTT CAG TGG AAC TAT AC - 3?) (Zijlstra et al., 2000). This primer set yield a fragment of of approximately 670bp, which is identical to that previously reported for M. javanica (Humphreys-Pereira et al., 2017; Baidoo et al., 2016; Zijlstra et al., 2000). Additionally, NADH dehydrogenase subunit 5 gene was amplified using NAD5F2 (5?- TAT TTT TTG TTT GAG ATA TAT TAG - 3?) and NAD5R1 (5?- CGTGAATCTTGATTTTCCATTTTT-3?) primers as described by Janssen et al. (2016). The GenBank accession number of the nad5 gene sequence is MH230176. The obtained the nad5 gene sequence was identical to the reference sequence of M. javanica provided by Janssen et al. (2016). To our knowledge, this is the first report of H. lupulus as a host of the Javanese root-knot nematode (M. javanica) in Florida., Centro de Estudios Parasitológicos y de Vectores

A population of cyst nematode with terminal protuberance was found in soil samples associated with and on the roots of Polygonum aviculare L. at N45°23.480′, W75°40.463′ in South Ottawa, Ontario. Both J2 and cysts were found. It was subsequently confirmed with morphological and molecular methods as Cactodera estonica Krall and Krall, 1978 (Krall and Krall, 1978). The cysts are dark brown, elongated with length/breadth ratio more than 2, and vulval fenestra circumfenestrate 33 ± 4.1 (20–48) μm in diameter. Vulval slit is short 16 ± 2.7 (13–20) μm. Not all cysts have bullae or underbridge, when present a few bullae scattered on the ventral side of the cyst wall and the underbridge is thin; vulval denticles were found in one specimen. Male not found. J2 measurements are body length at 505 ± 45 (420–630) μm, stylet 25 ± 4.4 (22–29) μm long, and tail 36 ± 3.1 (34–38) μm with a short hyaline portion 14 ± 3.0 (12–19) μm. Lateral fields with four incisures. Tail end is round. All of these are consistent with those of C. estonica, for which the elongated cyst and short hyaline in J2 are characteristic for the species. Ribosomal DNA of the ITS, 18S, and D2/D3 of 28S regions were PCR amplified from cysts and J2s using primers 18S (5′-TTGATTACGTCCCTGCCCTTT-3′) and 26S (5′-TTTCACTCGCCGTTACTAAGG-3′) (Vrain et al., 1992), D2A (5′-ACAAGTACCGTGAGGGAAAGT-3′) (Nunn, 1992) and D3B (5′-GACCCGTCTTGAAACACGGA-3′) (De Ley et al., 1999), and sequenced. The sequences of the ITS and D2/D3 regions of 1,480 and 1,363 bps, respectively, were deposited in Genbank with accession numbers MF774482 and MF774483. When blasted in to the NCBI database (August 2017), the ITS sequence was 99% similar to sequences of AF274417, a population of C. estonica from Belgium and of KX579922 from Turkey, and the D2/D3 sequence was 99% similar to sequences of HM560797 and HM560796, populations of C. estonica from China. This is the first reported case of this nematode species in Canada and the second for the western hemisphere (Norgren and Golden, 1986).