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he stunt nematodes, family Dolichodoridae, are migratory ectoparasites of roots. They feed on epidermal cells by inserting only the stylet tip into the cell's surface tissue. As one of the less common stunt nematodes, little is known about the Neodolichorhynchus sulcatus (de Guiran, 1967) Jairajpuri & Hunt, 1984. To date, it s been reported from Morocco (de Guiran 1967), Spain (Tobar-Jiménez 1970), Cameroon (Sakwe and Geraert 1991), India (Sultan et al. 1995) and Iran (Pourjam et al. 2011). Here we describe the first detection of N. sulcatus infecting pepper (variety: 1204 Alef Beit Zeraim) root from a farm in Ein Yahav, Arava Rift, Israel (30°39'54.3"N 35°15'02.9"E). In March 2019, we observed decline in development of pepper plants (Fig. S1). We recovered the nematodes from the pepper root zone at high population density. The nematodes were extracted from the soil using the Baermann tray technique. Identification was based on a combination of molecular and morphological methods. Genomic DNA was extracted from a single fresh nematode, amplicons from 18S rRNA, 28S D2–D3 rRNA, and intergenic spacer (ITS) region were generated following the procedure detailed in Qing et al. (2019), and sequencing was performed. The newly obtained sequences were submitted to GenBank with accession numbers MK96525–MK965256 (28S), MK965252 (18S), and MK965249 and MK965250 (ITS), providing the first rRNA data for N. sulcatus. Phylogenetic analysis placed this species as sister to Bitylenchus iphilus in 18S (98.15% similar in BLAST), sister to Paratrophurus bhutanensis in 28S (91.68% similar in BLAST), or sister to a well-supported clade containing Bitylenchus iphilus (91.35% similar in BLAST, highest match), B. maximus, B. hispaniensis, P. bhutanensis and P. bursifer in ITS (figures for phylogeny trees are available from https://photos.app.goo.gl/2Y7fToEftBopbnB67). Although our species were not clustered with other Neodolichorhynchus species, morphology and morphometry confirmed its identity as N. sulcatus (Fig. S2), including the cephalic region offset, basal bulb pyriform, a cuticle with 16 longitudinal ridges including the lateral fields, irregularly areolated lateral fields with three ridges, bursa not notched at tail tip, gubernaculum with smooth proximal end, and vulva lacking lateral flaps, tail cylindroid-conical with rounded and smooth terminus. Measurements (mean ± standard error, range, in μm) for female (n = 10): body length 801 ± 49.4 (731–901), anterior end to vulva 435 ± 34.8 (410–520), V value 54.2 ± 1.69 (52.4–57.7), lip height 4.53 ± 0.31 (4.39–5.41), stylet length 21.4 ± 0.37 (20.6–21.8), cone of stylet 11.4 ± 0.63 (10.7–12.8), anterior end to center of median bulb 86.0 ± 3.53 (78.7–91.3), pharynx length 146 ± 4.05 (139–153), maximum body width 25.6 ± 1.00 (24–27), anus/cloacal width 15.7 ± 1.39 (14.3–17.9), tail length 47.2 ± 3.85 (43.4–56.5); for male (n = 7): body length 786 ± 64.0 (704–874), lip height 4.34 ± 0.55 (3.67–5.24), stylet length 20.4 ± 0.73 (19.7–21.7), cone of stylet 10.9 ± 0.82 (10.3–12.7), anterior end to median bulb 81.2 ± 3.54 (75.2–87), pharynx length 138 ± 6.66 (132–148), maximum body width 22.6 ± 2.15 (20.4–25.8), anus/cloacalwidth 17.7 ± 1.50 (15.2–19.9), tail length 54.7 ± 5.67 (46.6–62.6), spicule length 26.3 ± 1.21 (24.2–27.6). To confirm pathogenicity, we performed inoculation assays in greenhouse conditions. Individual nematodes were manually picked and 300 juveniles were inoculated onto healthy pepper (variety: Maccabi) roots growing in sterile soil in a greenhouse. Three pots with four pepper plants per pot were inoculated, and three noninoculated pots served as a control. Nematodes were harvested from the root and soil 40 days after inoculation, yielding an average of 483 ± 75 nematodes per pot. We observed a reduction in plant growth and necrotic spots on the roots similar to those infected pepper in Ein Yahav. These results confirmed the nematode’s pathogenicity to pepper. To our knowledge, this is the first report of N. sulcatus infecting pepper plants in Israel.

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Occurrence of the stunt nematode Neodolichorhynchus sulcatus as pathogen of pepper (Capsicum annuum) in Israel
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Svetlana Duvrinin
Occurrence of the stunt nematode Neodolichorhynchus sulcatus as pathogen of pepper (Capsicum annuum) in Israel

he stunt nematodes, family Dolichodoridae, are migratory ectoparasites of roots. They feed on epidermal cells by inserting only the stylet tip into the cell's surface tissue. As one of the less common stunt nematodes, little is known about the Neodolichorhynchus sulcatus (de Guiran, 1967) Jairajpuri & Hunt, 1984. To date, it s been reported from Morocco (de Guiran 1967), Spain (Tobar-Jiménez 1970), Cameroon (Sakwe and Geraert 1991), India (Sultan et al. 1995) and Iran (Pourjam et al. 2011). Here we describe the first detection of N. sulcatus infecting pepper (variety: 1204 Alef Beit Zeraim) root from a farm in Ein Yahav, Arava Rift, Israel (30°39'54.3"N 35°15'02.9"E). In March 2019, we observed decline in development of pepper plants (Fig. S1). We recovered the nematodes from the pepper root zone at high population density. The nematodes were extracted from the soil using the Baermann tray technique. Identification was based on a combination of molecular and morphological methods. Genomic DNA was extracted from a single fresh nematode, amplicons from 18S rRNA, 28S D2–D3 rRNA, and intergenic spacer (ITS) region were generated following the procedure detailed in Qing et al. (2019), and sequencing was performed. The newly obtained sequences were submitted to GenBank with accession numbers MK96525–MK965256 (28S), MK965252 (18S), and MK965249 and MK965250 (ITS), providing the first rRNA data for N. sulcatus. Phylogenetic analysis placed this species as sister to Bitylenchus iphilus in 18S (98.15% similar in BLAST), sister to Paratrophurus bhutanensis in 28S (91.68% similar in BLAST), or sister to a well-supported clade containing Bitylenchus iphilus (91.35% similar in BLAST, highest match), B. maximus, B. hispaniensis, P. bhutanensis and P. bursifer in ITS (figures for phylogeny trees are available from https://photos.app.goo.gl/2Y7fToEftBopbnB67). Although our species were not clustered with other Neodolichorhynchus species, morphology and morphometry confirmed its identity as N. sulcatus (Fig. S2), including the cephalic region offset, basal bulb pyriform, a cuticle with 16 longitudinal ridges including the lateral fields, irregularly areolated lateral fields with three ridges, bursa not notched at tail tip, gubernaculum with smooth proximal end, and vulva lacking lateral flaps, tail cylindroid-conical with rounded and smooth terminus. Measurements (mean ± standard error, range, in μm) for female (n = 10): body length 801 ± 49.4 (731–901), anterior end to vulva 435 ± 34.8 (410–520), V value 54.2 ± 1.69 (52.4–57.7), lip height 4.53 ± 0.31 (4.39–5.41), stylet length 21.4 ± 0.37 (20.6–21.8), cone of stylet 11.4 ± 0.63 (10.7–12.8), anterior end to center of median bulb 86.0 ± 3.53 (78.7–91.3), pharynx length 146 ± 4.05 (139–153), maximum body width 25.6 ± 1.00 (24–27), anus/cloacal width 15.7 ± 1.39 (14.3–17.9), tail length 47.2 ± 3.85 (43.4–56.5); for male (n = 7): body length 786 ± 64.0 (704–874), lip height 4.34 ± 0.55 (3.67–5.24), stylet length 20.4 ± 0.73 (19.7–21.7), cone of stylet 10.9 ± 0.82 (10.3–12.7), anterior end to median bulb 81.2 ± 3.54 (75.2–87), pharynx length 138 ± 6.66 (132–148), maximum body width 22.6 ± 2.15 (20.4–25.8), anus/cloacalwidth 17.7 ± 1.50 (15.2–19.9), tail length 54.7 ± 5.67 (46.6–62.6), spicule length 26.3 ± 1.21 (24.2–27.6). To confirm pathogenicity, we performed inoculation assays in greenhouse conditions. Individual nematodes were manually picked and 300 juveniles were inoculated onto healthy pepper (variety: Maccabi) roots growing in sterile soil in a greenhouse. Three pots with four pepper plants per pot were inoculated, and three noninoculated pots served as a control. Nematodes were harvested from the root and soil 40 days after inoculation, yielding an average of 483 ± 75 nematodes per pot. We observed a reduction in plant growth and necrotic spots on the roots similar to those infected pepper in Ein Yahav. These results confirmed the nematode’s pathogenicity to pepper. To our knowledge, this is the first report of N. sulcatus infecting pepper plants in Israel.

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