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Prionchulus jonkershoekensis n. sp. is described from South Africa and illustrated using morphological, morphometric, and molecular techniques. This species is characterized by its body length (1.78-2.14 mm); the size of buccal cavity (38-44 × 24-31 µm), lower dorsal tooth position in relation to buccal cavity base, the position of amphidial aperture just above dorsal tooth apex, pars proximalis vaginae with almost straight walls, and tail 144-158 µm long with sickle shaped posterior third part. Phylogenetic analyses based on 18 S rDNA and 28 S rDNA of P. jonkershoekensis n. sp. revealed close relationships of the new species with Prionchulus punctatus and Prionchulus muscorum. This is also an additional geographical record for the genus from South Africa.Sampling for needle nematodes was carried out in a grapevine area in Thessaloniki, North Greece and two nematode species of Longidorus (L. pauli and L. pisi) were collected. Nematodes were extracted from 500 cm3 of soil by modified sieving and decanting method, processed to glycerol and mounted on permanent slides, and subsequently identified morphologically and molecularly. Nematode DNA was extracted from single individuals and PCR assays were conducted to amplify D2-D3 expansion segments of 28S rRNA, ITS1 rRNA, and partial mitochondrial coxI regions. Morphology and morphometry data obtained from these populations were consistent with L. pauli and L. pisi identifications. To our knowledge, this is the first report of L. pauli for Greece, and the second world report after the original description from Idleb, Syria, extending the geographical distribution of this species in the Mediterranean Basin.Three Iranian populations of Discolaimium dubium are studied, including their morphological and morphometric characterization, molecular analysis (LSU-rDNA) and the description of the male for the first time. For comparative purposes, this species is distinguished by its 1.10 to 1.40 mm long body, lip region offset by constriction and 8 to 10 µm wide, odontostyle 7.5 to 10.5 µm long with aperture occupying 59 to 76% of total length, neck 300 to 362 µm, pharyngeal expansion 127 to 181 µm long or 44 to 46% of the total neck length, uterus simple and 38 to 53 µm or 1.2 to 1.5 times the body diameter long, V = 52 to 58, tail conical (32-38 µm, c = 32-43, c' = 1.6-2.0) with rounded tip and a hyaline portion occupying 14 to 15% of tail length, spicules 30 to 32 µm long, and two or three widely space ventromedian supplements with hiatus. Both morphological and molecular data support its belonging to the genus Aporcella, whose monophyly is confirmed and to which the species is formally transferred as A. dubia (Das et al., 1969) comb. n.Camacolaimidae is a clade of nematodes that include both free-living epistrate feeding forms and parasites of marine protozoans and invertebrates. Neocamacolaimus parasiticus is a parasite of marine polychaete worms. Given its phylogenetic affinities to free-living species, Neocamacolaimus can be a reference for research of the origin of parasitism in an aquatic environment. Here, we present a draft transcriptome obtained from a single post-parasitic juvenile individual of this species. The final assembly consists of 19,180 protein coding sequences (including isoforms) with the following BUSCO scores for Nematoda 65.38% complete, 9.06% partial, and 25.56% missing, and for Metazoa 79.45% complete, 3.17% partial, and 17.38% missing.The study of species biodiversity within the Caenorhabditis genus of nematodes would be facilitated by the isolation of as many species as possible. So far, over 50 species have been found, usually associated with decaying vegetation or soil samples, with many from Africa, South America and Southeast Asia. Scientists based in these regions can contribute to Caenorhabditis sampling and their proximity would allow intensive sampling, which would be useful for understanding the natural history of these species. However, severely limited research budgets are often a constraint for these local scientists. In this study, we aimed to find a more economical, alternative growth media to rear Caenorhabditis and related species. We tested 25 media permutations using cheaper substitutes for the reagents found in the standard nematode growth media (NGM) and found three media combinations that performed comparably to NGM with respect to the reproduction and longevity of C. elegans. These new media should facilitate the isolation and characterization of Caenorhabditis and other free-living nematodes for the researchers in the poorer regions such as Africa, South America, and Southeast Asia where nematode diversity appears high.A population of Xiphinemella esseri, recently collected under the canopy of associated live oak trees in north Florida, was studied and described with an integrative approach, including the first molecular study of the genus. This Florida population is characterized by its 2.30 to 3.32 mm long body, labial disc well developed, lip region offset by constriction, and 16.5 to 17.5 μm broad, odontostyle 46 to 49 μm long with minute aperture, neck 288 to 296 μm long, pharyngeal expansion occupying 28 to 30% of total neck length, uterus a tripartite tube-like structure, pars refringens vaginae absent, vulva transverse (V = 45.4-49.7%), tail short and rounded (18-28 μm, c = 94-158, c' = 0.6-0.9), spicules 41 to 45 μm long, and 8 to 10 irregularly spaced ventromedian supplements bearing hiatus. The phylogenetic analysis inferred from the D2-D3 expansion segments of 28S rRNA gene and 18S rRNA gene sequences showed that X. esseri clustered with other dorylaims from the family Leptonchidae. A brief discussion about the distribution and biological considerations of X. esseri is also provided.Resistance to Meloidogyne incognita races 1 and 3 and race 1 of M. arenaria is imparted to flue-cured tobacco by the gene Rk1. Meloidogyne arenaria race 2 is not controlled by Rk1 and has become prevalent in Virginia. A second form of resistance effective against M. javanica, Rk2, is also increasingly available commercially. Greenhouse and field trials including a root-knot susceptible cultivar, cultivars homozygous for Rk1 or Rk2, and cultivars possessing both genes were conducted in 2018 and 2019 to investigate the effect of Rk1 and/or Rk2 on parasitism and reproduction of M. arenaria race 2. Plants were inoculated with 5,000 M. arenaria race 2 eggs in the greenhouse or infested by a native nematode population in the field. Data were collected after 28 days (greenhouse) or every 3 weeks following transplant until 18 weeks in the field and included root galling index, nematodes present in roots, egg mass numbers, and egg counts; reproductive indices were also calculated. We found that the combination of Rk1 and Rk2 provides greater resistance to M. CDK inhibitor arenaria race 2 than either gene alone. While the effect of either gene alone was inconsistent, we did observe some significant reductions in galling and reproduction associated with each gene relative to the susceptible control.Fluopyram (Velum® One) is a synthetic nematicide and azadirachtin (Molt-X®) is a biological nematicide. Both have shown promise against plant-parasitic nematodes on several agriculturally important crops. There is a lack of information on integration of pre-plant sunn hemp (Crotalaria juncea) cover crop with these post-plant nematicides, aiming to improve plant-parasitic nematodes management and mitigate any detrimental effects on free-living nematodes. Three field trials were conducted to investigate the effects of fluopyram alone or in combination with pre-plant sunn hemp cover crop, and azadirachtin combined with pre-plant sunn hemp on Rotylenchulus reniformis and Meloidogyne spp., and free-living nematodes. Zucchini (Cucurbita pepo) and tomato (Solanum lycopersicum) were grown in Trials I and II, and sweet potato (Ipomoea batatas) only was grown in Trial III. In all three trials, early applications of fluopyram at crop planting were effective in suppressing the abundance of Meloidogyne spp. (M. incognita arketable yield of sweet potato was increased by 4.5-6.4 folds in all the fluopyram treatments but was only increased 61.5% by sunn hemp plus azadirachtin treatment. While fluopyram alone often reduced the abundance of free-living nematodes, integrating with sunn hemp mitigated the negative impacts of fluopyram on soil health.Return of plant residues to the soil is a sustainable way of enhancing plant growth, health, and levels of soil quality. In Kenya, maize plant residues are the most commonly returned plant material in many agro-ecosystems. For any plant material to release nutrients into the soil, it must undergo a decomposition process that is usually affected by various organisms, especially nematodes. Despite their great contribution to the breakdown of plant organic matter, there is a dearth of information on the interaction between maize residues and free-living nematodes (FLN) in Kenya. In this respect, this study aimed to assess the influence of decomposing maize residues on FLN dynamics and the soil food web in Mwea, Kenya. The experimental plots were set up in a randomized complete block design, comprising of decomposition plots (incorporated with maize residue to a depth of 30 cm at a rate of 5 tons/hectare), while the plots unincorporated with maize residues were used as the control. Each treatment consisted of fou was lower.Plant-parasitic nematodes are a major pest of turfgrass in the United States, yet there are few options for successful management. Most current management strategies rely on the use of a limited number of chemical nematicides, so finding a new management option for nematode suppression would be extremely valuable for turfgrass managers. The aim of this study is to evaluate a new nematicide, fluazaindolizine (Reklemel™ active), for its ability to reduce plant-parasitic nematode population density and improve turfgrass quality. Separate research trials were conducted on bermudagrass infested with Belonolaimus longicaudatus and Meloidogyne incognita in greenhouse, microplot, and field settings over 2018 and 2019. Both greenhouse evaluations demonstrated multiple rates of fluazaindolizine reduced B. longicaudatus population density, and one of the two M. incognita trials showed multiple rates of fluazaindolizine reduced nematode population density. Fluazaindolizine was also effective at reducing population density of both B. longicaudatus and M. incognita in microplot settings for both 2018 and 2019, and a significant improvement in turf quality was observed for both visual turfgrass ratings and NDVI. Field trials demonstrated a significant reduction for both B. longicaudatus and M. incognita population density by multiple rates of fluazaindolizine, but no significant differences in turf quality ratings were observed. Overall, fluazaindolizine shows promise as a chemical nematicide for plant-parasitic nematode management on turfgrass.During a survey on the biodiversity of plant-parasitic nematodes of natural areas in Botswana, Bitylenchus ventrosignatus was discovered around the rhizosphere of wild grass. The nematodes were extracted using the tray method and then fixed according to the available protocols. The morphological characters fit well with the description of B. ventrosignatus. In addition, molecular analysis using 18 S and 28 S rDNA indicated 98% (KJ461617) and 95% (KJ461567) similarity with the Spanish population of B. ventrosignatus. The phylogenetic analysis of 18 S and 28 S rDNA placed the examined population with other populations of B. ventrosignatus in a group with a posterior probability support value of 100. According to published literature, this is the first report of B. ventrosignatus from Botswana.