Morphological and morphometrical identification of Meloidogyne populations from various crop production areas in South Africa with emphasis on M. enterolobii
Rashidifard, Milad
Fourie, Hendrika
Daneel, Mieke Stefanie
Marais, Mariette
Zootaxa
2019
2019-08-22
4658
2
251
274
Yang & Eisenback, 1983
Yang & Eisenback
1983
[151,758,1036,1063]
Secernentea
Heteroderidae
Meloidogyne
Animalia
Tylenchida
4
255
Nematoda
species
enterolobii
= Meloidogyne mayaguensis Rammah & Hirschmann, 1988 Figures 3to 6. Measurements: Tables 3to 6b TABLE 3.Morphometrical (in µm) data (means, standard deviations and ranges) of anterior end of Meloidogynespp females. . Characteristics M. enterolobii M. incognita M. javanica (n = 10) (n = 5) (n = 10) Stylet length 20 1± 2.7 2 21 ± 0.4 19 ± 1.3 (16–24) 3 (20–21) (17–21) Stylet knobs height 2 ± 0.4 2 ± 0.3 2 ± 0.3 (1–3) (1–2) (2–3) Stylet knobs width 3 ± 0.5 3 ± 0.4 3 ± 0.2 (3–4) (3–4) (3–4) Opening of dorsal gland posterior to stylet knobs 4 ± 1 4 ± 0.4 4 ± 0.4 (4–7) (3–5) (3–4) Anterior end to beginning of median bulb 71 ± 7.6 74 ± 4.7 74 ± 7.7 (60–82) (67–80) (66–87) Median bulb length 40 ± 4. 39 ± 6.1 42 ± 6.1 (36–48) (30–48) (28–48) Median bulb diameter 39 ± 1.8 37 ± 2.6 38 ± 2.6 (37–43) (34–41) (32–40) Neck length 169 ± 25.5 167 ± 19.9 155 ± 21.9 (130–210) (141–190) (135–196) 1Mean; 2Standard Deviation, 3Range (min–max) FIGURE 3.Variation in the perineal-pattern morphology within and among different mature females of Meloidogynespp. populations sampled in agri- and horticultural production areas during 2015 and 2016. A–D: Meloidogyne enterolobii; E–H: Meloidogyne javanica; I–L: Meloidogyne incognita; M: Meloidogyne hapla. Female (n=341 perineal-patterns; n=10 intact females).Body pear-shaped and cuticle finely annulated. Head not distinctly off set from body. Stylet 16–24 µmlong, conus slightly curved dorsally, stylet knobs offset, longitudinally divided from each other by groove ( Fig. 4). Dorsal gland opening 4–7 µmposterior to stylet knobs. Excretory pore position variable, near median bulb in most specimens. Median bulb well developed, 60–82 µmfrom anterior end with rounded median bulb valve. Neck 130–210 µmlong. Perineal-pattern round to oval with medium to high dorsal arches (40 % of specimens) in shape with fine striae, phasmids pronounced and 2–3 µmin diameter, fine striae surrounding the tail terminus area ( Fig. 3). Interphasmidial distance 15–36 µm, fine striae present on lateral sides of vulva. Vulval slit 23–30 µmlong and vulva-anus distance 12–45 µmlong. FIGURE 4.Light microscopic photos of anterior part of Meloidogynespp. females obtained from roots of agri- and horticultural crops in South African production areas during 2015 and 2016. A, B: M. enterolobii; C, D: M. incognita; E, F: M. javanica. Male (n= 19).Body vermiform, 1010–1837µmlong, tapered anteriorly, rounded posteriorly. Head set off with high and round cap, labial framework moderately developed. Stylet 20–26 µmlong, conus straight, basal knobs sloping backward ( Fig. 5). Dorsal gland opening 3–6 µmposterior to stylet knobs. Median bulb oval to elongated, followed by narrow isthmus. Excretory pore situated 113–185 µmfrom anterior end. Lateral fields areolated with four lateral lines. Phasmids small, opposite to cloaca. Tail 12–17 µmlong. Spicule arcuate, 26–33 µmlong. Gubernaculum simple, 9–13 µmlong. Second-stage juvenile (n= 173).Body shape vermiform, 352–462 µmlong, narrow and tapered anteriorly and posteriorly. Head truncated and not off set ( Fig. 6). Stylet 11–15 µmlong, cone straight. Stylet knobs large and sloping backward. Dorsal gland opening 2–4 µmposterior to stylet knobs. Median bulb 42–58 µmfrom anterior end, oval with thickened lumen lining. Excretory pore 62–96 µmfrom anterior end. Tail 39–68 µmlong, tapering, with defined hyaline tail terminus. FIGURE 5.Light microscopic photos of anterior part of Meloidogynespp. males obtained from roots of agri- and horticultural crops in South African production areas during 2015 and 2016. A–C: M. enterolobii; D–F: M. incognita; G–I: M. javanica. Remarks.Although morphological and morphometrical characteristics of this species compared well with the original description of the species by Yang & Eisenback (1983)and subsequent reports from Florida ( Brito et al. 2004), and Karssen et al. (2012)as well as original description of the Puerto Ricopopulation ( M. mayaguensis) by Rammah & Hirschmann (1988), some differences were observed. The South African populations differ from the typedescription in a longer stylet in females ( 16–24 µm vs 13–18 µm) and slightly shorter interphasmidial distance ( 15–36 µm vs 22–42 µm). It also differs from the female stylet length in the Florida and Puerto Ricopopulations ( 13–15 µmand 14–17 µm, respectively). The South African populations also differ from the Puerto Ricopopulation in a longer vulva-anus distance ( 12–45 µmvs 13–21 µm). Male specimens of the South African populations differed from the Florida populations in: longer body length ( 1010–1837µm vs 856–1501 µm), stylet length ( 20–26 µm vs 17–22 µm) and spicule length ( 26–33 µm vs 23–29 µm. The South African J 2 specimensdiffered in body length from the typepopulation, the Puerto Ricoand Florida populations ( 352–462 µm vs 405–473 µm; 390–528 µmand 377–491 µm), respectively. However, the stylet length for South African populations ( 11–15 µm) was longer than that reported ( 11–12 µm) by Rammah & Hirschmann (1988)for the Puerto Ricopopulation. South African M. enterolobiispecimens also had longer tails compared to the Karssen et al. (2012)populations ( 37–68 µm vs 45–57 µm).