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1.
Meloidogyne petuniae n. sp. is described and illustrated from specimens parasitic on petunia (Petunia hybrida L.) in Brasilia, Brazil. The perineal pattern of the female is elongate to ovoid with a high, squarish arch and widely spaced, coarse striae. The stylet of the female is 12.9-16.5 µm long and has three small, rounded knobs that are distinctly set off from the shaft. Each knob is marked by a deep longitudinal indentation posteriorly and anteriorly. In SEM the base of the shaft appears to be divided into six distinct ridges. The excretory pore opens about 15.4-53.6 µm from the head end. Males are approximately 0.8-2.2 mm long. Most specimens have a high and narrow head cap, but in some the head cap is narrow and low. The stylet of the male is 21.1-26.0 µm long and has small, rounded knobs, set off from the shaft, but not indented as in the female. Second-stage juveniles are 353-464 µm long; the labial disc is fused with the medial lips to form a dumbbell-shaped head cap; the medial lips are indented posteriorly; and the head region is marked with one to two irregular annulations. The stylet is 9.2-10.8 µm long and has rounded, posteriorly sloping knobs. The tail is slender, approximately 46.4-57.2 µm long, and has a short hyaline terminus, 10.3-13.5 µm long. The somatic chromosome number is 2n = 41 and the esterase phenotype is VS1-S1, with S1 being a weak band. The malate dehydrogenase phenotype is N1, which is unique for this species. Petunia, tomato, tobacco, pea, and bean are good hosts; pepper, watermelon, and sweet corn are poor hosts; and peanut, cotton, and soybean are non-hosts. Galls produced by this species are smaller on petunia than on tomato.  相似文献   

2.
Meloidogyne mayaguensis n. sp. is described and illustrated from specimens obtained from galled roots of eggplant, Solanum melongena L., from Puerto Rico. The perineal pattern of females is round to ovoid with fine, widely spaced striae. It has occasional breaks of striation laterally and a circular tail tip area lacking striae. The stylet, 15.8 μm long, has reniform knobs that merge gradually with the stylet shaft. Males have a high, rectangular, smooth head region, not set off from the body contour. The labial disc is continuous with the medial lips which do not slope posteriorly. The styler, 22.9 μm long, has large rounded backward sloping knobs; the shaft is of uneven diameter. Mean body length of second-stage juveniles is 453.6 μm. The truncate head region is not annulated, and the rounded, slightly raised labial disc and the crescentic medial lips form dumbbell-shaped lip structures. The stylet, 11.6 μm long, has rounded, posteriorly sloping knobs. The slender tail, 54.4 μm long, gradually tapers to a bluntly pointed tip. Tomato, tobacco, pepper, and watermelon are good hosts; cotton and peanut are not hosts. M. mayaguensis n. sp. reproduces by mitotic parthenogenesis and has a somatic chromosome number of 2n = 44-45. The enzyme patterns are unique among Meloidogyne species.  相似文献   

3.
Meloidogyne hispanica n. sp. is described and illustrated from specimens obtained from peach rootstock, Prunus persica silvestris Batsch, from the Seville district of Spain. The perineal pattern of the female is oval shaped to rectangular with low dorsal arch and often widely spaced lateral lines with fringe-like striae. The stylet, 14.1 μm long, has broad, distinctly set off knobs. Males have a high, rounded head cap that slopes posteriorly. Labial disc and medial lips are fused to form elongate lip structures. The robust styler, 23.5 μm long, has large, rounded knobs that are slightly set off from the shaft. Mean second-stage juveniles length is 392.6 μm. The truncate head region is generally not annulated. The distinctly rounded and raised labial disc and the crescent-shaped medial lips form dumbbell-shaped lip structures. The stylet, 11.1 μm long, has rounded, posteriorly sloping knobs. The slender tail, 46.4 μm long, has large irregular-sized annules in the posterior region and ends in a bluntly rounded tip. Tomato was a good host; tobacco, pepper, and watermelon were poor hosts; cotton and peanut were nonhosts. Meloidogyne hispanica n. sp. reproduces by mitotic parthenogenesis and has a somatic chromosome number of 2n = 33-36. The esterase pattern is unique among Meloidogyne species.  相似文献   

4.
Meloidogyne pini n. sp. is described from sand pine, Pinus clausa, in Georgia. The perineal pattern of the female has a large cuticular ridge surrounding a deeply recessed perivulval area. The lateral fields are marked by transverse striae. The female stylet is 14.6 μm long, and the knobs are small, rounded, and set off from the straight and narrow shaft. The excretory pore is near the level of the base of the stylet. The labial disc of the male is large, rounded, and fused with the crescent-shaped medial lips. The head region is smooth, the styler is 20.8 μm long, and the cone is more than twice as long as the shaft. The knobs are rounded and set off from the shaft. In the second-stage juvenile, the labial disc, medial lips, and lateral lips form one smooth, continuous, ovoid head cap. Mean juvenile length is 434 μm, stylet length is 12.8 μm, and tail length is 44.4 μm. M. pini n. sp. also parasitizes loblolly and slash pine. Additional morphological details of M. megatyla are presented.  相似文献   

5.
Meloidogyne morocciensis n. sp. is described from specimens parasitic on peach rootstock from Morocco. This species exhibits a combination of morphological characters similar to M. arenaria, M. incognita, and M. javanica. The perineal pattern of females is oval to squarish with a moderately high to high dorsal arch, and widely spaced, smooth striae; lateral lines are absent. The stylet, 16.5 μm long, has transversely ovoid, set-off knobs. Males have a set-off, annulated head region. The large, rounded labial disc is distinctly demarcated from the crescent-shaped medial lips; lateral lips are absent. The robust stylet, 24.6 μm long, has large, rounded knobs that taper slightly posteriorly. Mean second-stage juvenile (J2) length is 401 μm. The set-offhead region has incomplete annulations; the lip structures are dumbbell shaped. The stylet, 12.3 μm long, has rounded knobs that slope posteriorly. The J2 tail, 52.6 μm long, has irregularly sized annules in the posterior region and ends in a bluntly rounded tip. Tomato, tobacco, pepper, and watermelon are good hosts; cotton and peanut are not hosts. Meloidogyne morocciensis n. sp. reproduces by mitotic parthenogenesis and has a somatic chromosome number of 47-49. Its esterase phenotype is identical with the three-banded phenotype (A3) of M. arenaria.  相似文献   

6.
Meloidogyne trifoliophila n. sp. is described from white clover collected at Ames Plantation, Fayette County, Tennessee. The perineal pattern is rounded, with long, smooth striae and rounded arch, and without distinct lateral lines or perivulval striae. The female stylet is 12.6-15.5 μm long, the excretory pore is level with or up to one stylet length posterior to the stylet knobs, and the vulva is subterminal. The posterior terminus is weakly protuberant. The male lateral field is composed of approximately eight repeatedly broken or forked incisures. The male stylet is 17.0-18.9 μm long, the stylet knobs are rounded and sloping, gradually merging with the shaft, and the head region consists of one large annule. Second-stage juveniles are 357-400 μm long, with a stylet length of 11.9-13.6 μm and one head annule. The tail tapers to a slender tip. This new species is similar to M. graminicola and M. triticoryzae but differs from them in perineal pattern and lateral field morphology, and numerous morphometric characters.  相似文献   

7.
A root-knot nematode parasitizing coffee in Paran  State, Brazil, is described as Meloidogyne paranaensis n. sp. The suggested common name is Paraná coffee root-knot nematode. The perineal pattern is similar to that of M. incognita; the labial disc and medial lips of the female are fused and asymmetric and rectangular; the lateral lips are small, triangular, and fused laterally with the head region. The female stylet is 15.0-17.5 μm long, with broad, distinctly set-off knobs; the distance from the dorsal esophageal gland orifice (DGO) to the stylet base is 4.2-5.5 μm. Males have a high, round head cap continuous with the body contour. The labial disc is fused with the medial lips to form an elongate lip structure. The head region is frequently marked by an incomplete annulation. The stylet is robust, 20-27 μm long, usually with round to transversely elongate knobs, sometimes with one or two projections protruding from the shaft. The stylet length of second-stage juveniles is 13-14 μm, the distance of the DGO to the stylet base is 4.0-4.5 μm, and the tail length is 48-51 μm. Biochemically, the esterase (F₁) and malate dehydrogenase (N₁) phenotypes are the most useful characters to differentiate M. paranaensis from other species. However, the esterase phenotype appears similar to that of M. konaensis. Reproduction is by mitotic parthenogenesis, 3n = 50-52. In differential host tests, tobacco, watermelon, and tomato were good hosts, whereas cotton, pepper, and peanut were nonhosts.  相似文献   

8.
Meloidogyne enterolobii n. sp. is described and illustrated from roots of pacara earpod tree, Enterolobium contortisiliquum (Vell.) Morong, on Hainan Island in China. The perineal pattern of the female is usually oval shaped, the striae are fine to coarse, the dorsal arch is moderately high to high and usually rounded, and the phasmids are large. The stylet knobs in females are divided longitudinally by a groove so that each knob appears as two. The mean distance of the excretory pore to the anterior end in the female is 62.9 μm. Males have a large, rounded labial disc that fuses with the medial lips to form a dorso-ventrally elongate head cap. The labial disc is slightly elevated, and the medial lips are crescent shaped. The second-stage juvenile mean body length is 436.6 μm. The lateral lips are large and triangular in face view. The tail is 56.4 μm long and narrow with a broad, bluntly rounded tip. M. enterolobii n. sp reproduces well on E. contortisiliquum and causes severe damage. Other good hosts include cotton, resistant tobacco ''NC 95,'' pepper, watermelon, and tomato.  相似文献   

9.
Meloidogyne platani n. sp. is described and illustrated from specimens obtained from roots of American sycamore, Platanus occidentalis, in Virginia. This new species shows certain similarities with M. arenaria but differs from it by a number of distinctive characters. The perineal pattern of females is rounded with fine, wavy to zig-zag striae and raised, convoluted striae in the inner lateral line regions. The stylet of females is 16.5 μm long with large, rounded stylet knobs set off from the shaft. Males have a low head cap and smooth head region. The styler length is 22.0 μm, and the stylet knobs are rounded and set off from the shaft. Mean second-stage juvenile length is 443.0 μm, and stylet length is 12.2 μm. The head region of juveniles is not annulated, and the tail has a definite terminus. This nematode causes severe galling and reproduces well on sycamore. Other good hosts include white ash and tobacco cv. NC 95. M. platani n. sp. reproduces by mitotic parthenogenesis and has a somatic chromosome number of approximately 45 (2n).  相似文献   

10.
Meloidogyne konaensis n. sp. is described from coffee from Kona on the island of Hawaii. The perineal pattern of the female is variable in morphology, the medial lips of the female are divided into distinct lip pairs, and the excretory pore is 2-3 stylet lengths from the base of the stylet. Mean stylet length is 16.0 μm, and the knobs gradually merge with the shaft. The knobs are indented anteriorly and rounded posteriorly and the dorsal esophageal gland orifice (DEGO) is long, 3.5-7 μm. The morphology of the stylet of the male is the most useful diagnostic character, with 6-12 large projections protruding from the shaft. One medial lip may be divided into distinct lip pairs. A large intestinal caecum often extends nearly to the level of the DEGO. Mean juvenile length is 502 μm, mean stylet length is 13.4 μm, and mean tail length is 58 μm. The tail may be distinctly curved ventrally and the phasmids are located in the ventral incisure about one anal body width posterior to the anus.  相似文献   

11.
Meloidogyne carolinensis n. sp. is described from cultivated highbush blueberry (cultivars derived from hybrids of Vaccinium corymbosum L. and V. lamarckii Camp) in North Carolina. The perineal pattern of the female has a large cuticular ridge that surrounds the perivulval area, and the excretory pore is near the level of the base of the stylet. The stylet is 15.9 μm long and the knobs gradually merge with the shaft. The head shape and stylet morphology of the male are quite variable. The typical head and four variants, as well as the typical stylet and two variants, are described. The labial disc, medial lips, and lateral lips of second-stage juveniles are fused and in the same contour. The head region is not annulated. Mean juvenile length is 463.7 μm, stylet length is 11.9 μm, and tail length is 42.5 μm.  相似文献   

12.
Aphelenchoides microstylus n. sp. and Seinura onondagensis n. sp., a nematode predator, are described from dead Scots pine (Pinus sylvestris L.) in Onondaga County, New York. Females of A. microstylus are 370 to 485 µm long. The body is slender and tapers posteriorly to an amucronate, pointed terminus. The head is continuous with the body, and lips bear a stylet guide. Diagnostic characters of females are three incisures in the lateral field, a short stylet (6-7.5 µm) with small basal knobs, a single row of oocytes, and a long postuterine sac (25-50 µm). Males are characterized by small spicules (10-11µm); two pairs of post-anal, subventral papillae; and a single row of spermatocytes. A bursa and gubernaculum are absent. Seinura onondagensis females are characterized by a body of moderate length (475-595 µm), finely annulated cuticle, and a slightly set-off head. Diagnostic characters are four incisures in the lateral field, long stylet without basal knobs (17-22 µm), single row of oocytes, and presence of a postuterine sac (14-38 µm). Males are unknown. The monospecific genus Indaphelenchus is proposed as a synonym of Seinura, and S. siddiqii n. comb. is proposed for the only species, I. siddiqii.  相似文献   

13.
Meloidogyne polycephannulata n. sp. is described from specimens collected from an area cultivated with carrot cv. Brasilia, in the city of Rio Paranaíba, in the region of Alto Paranaíba, Minas Gerais State, Brazil. The perineal pattern of the female is circular to ovoid with a high dorsal arch that has widely spaced, coarse annulations. The lateral field may have a deep furrow separating the dorsal and ventral arches. The medial lips are short and wide, whereas the lateral lips are large and triangular. The female stylet is 15-16 μm long with wide knobs, distinctly divided by an indentation in the center. Its tip is slightly curved dorsally. The excretory pore opens 34-65 μm from the anterior end. Females retain eggs and second-stage juveniles in their body cavity, similar to that of the cyst-forming nematodes. Males are 1.3-1.7 mm long and have a high head cap that is rounded and slopes posteriorly. The labial disc is fused to the medial lips. The head region has several irregular annulations that are similar in appearance to the first or second body annules that are likewise irregular, making the head region appear to be extremely large. The stylet of the male is 21-24 μm long; it is slender, and has small, rounded knobs, that are distinctly indented medially and appear heart-shaped. The shaft has several tiny projections throughout its length. Mean second-stage juvenile length is 411.7 μm. The juvenile head cap is elevated, the medial lips are small, and the lateral lips are elongate to triangular-shaped. The head region has several short, incomplete and irregular transverse annulations. The juvenile stylet is 14-23 μm long with small, rounded, and sloping knobs. The thin tail ends with a short hyaline portion that is variable in size (16-26 μm) and with a small, rounded tip. Isozyme profiles of esterases from Meloidogyne javanica show 3 strong bands (SB) at Rm 46, 59, and 66; profiles of M. polycephannulata n. sp. show a SB at Rm 47 and a weak band (WB) at Rm 52; M. petuniae has two SB at Rm 44 and 53; M. phaseoli has a SB at 53, 58, and 64 Rm; M. brasilensis has three SB at Rm 40, 58, and 66 and a WB at Rm 71; M. pisi has a SB at Rm 40, 60, and 64 and two WB at 46 and 50 Rm. Data from sequencing the 18S rDNA region of M. polycephannulata n. sp. confirms that it is different from M. arabicida, M. arenaria, M. ethiopica, M. incognita, M. javanica, M. paranaensis, and M. thailandica. Sequence identity among these eight species ranged between 85 to 93.4%. Meloidogyne polycephannulata n. sp. reproduces very well on carrot and tomato; poorly on pepper; and not at all on cotton, peanut, tobacco, watermelon, and sweet corn.  相似文献   

14.
15.
Meloidogyne microcephala n. sp. is described and illustrated from specimens obtained from tobacco (Nicotiana tabacum L.) in Thailand. The female perineal pattern usually has a low dorsal arch, coarse striae, and a series of small cuticular flaps around the tail terminus. The stylet of the female is 14.4 μm long, with large, square to rectangular stylet knobs, The distinctive male head region is narrow, small, and truncate with a low, flattened head cap. The stylet length is 20.6 μm, and the knobs are small, angular, and set off from the shaft. Mean length of second-stage juveniles is 457.5 μm, and stylet length is 9.3 μm. The tail tip in the juveniles is set off from the rest of the tail as a small finger-like projection. M. microcephala reproduces by mitotic parthenogenesis, and has a chromosome number of 2n = 36.  相似文献   

16.
Four new species of Criconematoidea are described from Hoste Island, Chile. Criconema certesi n. sp. is distinguished by the fine, spine-like, cuticular extensions on body annuli; projection of annuli into rows of scales on posterior part of body; single, smooth, labial annulus set off by short collar from second (first body) annulus which is about same diameter as first (labial) annulus. Male with prominent caudal alae, slender curved spicules, and four incisures in lateral field. Ogma terrestris n. sp. is distinguished by small scales with rounded tips bearing minute, short bristles; scales number 21 at mid-body; and first (labial) annulus rounded, not retrorse, not set off from succeeding annuli, narrower in diameter from second (first body) annulus. Hemicycliophora macrodorata n. sp. is distinguished by its large size (L = 1.52 [1.28-1.72] mm); large stylet (146 [127-161] μm); annuli = 297 (280-315); tail slightly spicate, lateral field with or without interruptions of incisures, occasional anastomoses; and males with U-shaped spicules. Paratylenchus fueguensis n. sp. is distinguished by its prominent stylet with large, rounded knobs (4-5 μm across); cephalic region rounded not at all set off; lateral field with four incisures; lateral vulvar membranes present; and male tail short, strongly curved (almost 180°) ventrad.  相似文献   

17.
A root-knot nematode from Portugal, Meloidogyne lusitanica n. sp., is described and illustrated from specimens obtained from olive trees (Olea europaea L.). Females of the new species have a characteristic perineal pattern with medium to high trapezoidal dorsal arch with distinct punctuations in the tail terminus area. The excretory pore is located posterior to the stylet, about 1.5-2.5 stylet lengths from the anterior end. The stylet is 17.1 μm long with pear-shaped knobs. Males have a rounded, posteriorly sloping head cap and head region not annulated. The robust stylet, 24.5 μ long, has large, elongate knobs. Mean length of the second-stage juveniles is 449.5 μm, stylet length 14.2 μm, and tail length 44.1 μm. Scanning electron microscope observations provide further details of perineal patterns and head and stylet morphology of females, males, and second-stage juveniles. Meloidogyne lusitanica n. sp. did not reproduce on any of the differential hosts used to separate the four most common Meloidogyne species. The common name "olive root-knot nematode" is proposed for M. lusitanica n. sp.  相似文献   

18.
Males and females of Paurodontella auriculata n. sp. are described and illustrated and the genus emended. The species is characterized by a short, robust body of 355-525 μm, a stylet length of 7-8 μm, lateral field with 5-6 incisures, and a conoid, attenuated tail 1.5 times the vulva-anus distance. Primary characters used in emending the genus are asymmetrical stylet knobs, absence of lateral lips, a deep slit-like amphid dividing the submedian lips to base of head, where open lateral sides are covered by a large auriform cuticular flap, and variable length of the basal esophageal bulb stem and male bursa.  相似文献   

19.
Pratylenchoides hispaniensis n. sp. is described and illustrated from a bisexual population found in a natural habitat at Santa Elena, Jaen, central Spain. Its main distinctive characters are very long esophageal gland lobe (81-117 μm; N'' = 51-71) overlapping the intestine 3 to 5 times the body width; lateral field with six incisures; stylet knobs sloping posteriorly; labial disc encircled by the irregular sectors of the first annule; tail cylindrical, extremity annulated, and frequently with a slight dorsal indentation of the hyaline portion at the end of the lateral field. Pratylcnchoides hispaniensis n. sp. appears closely related to P. megalobatus and P. nevadensis. It differs from the former primarily by its longer body length (761-998 vs. 430-621 μm), longer stylet length (20.5-24.4 vs. 18-21 μm), six incisures in the lateral field vs. four for P. megalobatus, and posteriorly sloping stylet knobs vs. rounded or anteriorly flattened knobs in P. megalobatus. It differs from P. nevadensis mainly by the shape of the stylet knobs (sloping in P. hispaniensis vs. rounded in P. nevadensis), length of esophageal lobe (81-117 vs. 34-82 μm), and position of esophageal gland nuclei (all posterior to esophago-intestinal junction in P. hispaniensis vs. at least one nucleus anterior to junction in P. nevadensis).  相似文献   

20.
Meloidoderita salina sp. n. is described and illustrated from the halophytic plant Atriplex portulacoides L. (sea purslane) growing in a micro-tidal salt marsh in the Mont-Saint-Michel Bay in France. This new species is the first member of Meloidoderita Poghossian, 1966 collected from a saline environment, and is characterized by the following features: sedentary mature females having a small swollen body with a clear posterior protuberance; slightly dorsally curved stylet, 19.9 µm long, with posteriorly sloping knobs; neck region irregular in shape and twisted; well developed secretory-excretory (S–E) pore, with markedly sclerotized S-E duct running posteriorly; prominent uterus bordered by a thick hyaline wall and filled with eggs. The adult female transforms into a cystoid. Eggs are deposited in both egg-mass and cystoid. Cystoids of Meloidoderita salina sp. n. display a unique sub-cuticular hexagonal beaded pattern. Male without stylet, pharyngeal region degenerated, S-E duct prominent, deirids small, developed testis 97.5 µm long, spicules 18.4 µm long, cloacal opening ventrally protruded, small phasmids posterior to cloaca opening and situated at 5.9 (3.2–7.7) µm from tail end, and conical tail ending in a rounded terminus marked with one (rarely two) ventrally positioned mucro. Additionally, some young malesof the new species were observed enveloped in the last J2 cuticle. Second-stage juvenile body 470 µm long, with a 16.4 µm long stylet, prominent rounded knobs set off from the shaft, hemizonid anterior and adjacent to S-E pore, small deirids located just above S-E pore level, genital primordium located at 68–77% of body length, phasmids small and located at about 19 µm from tail tip, and tail 38.7 µm long, tapering to finely pointed terminus with a finger-like projection. Phylogenetic analyses based on the nearly full length small subunit ribosomal DNA sequences of Meloidoderita salina sp. n. revealed a close relationship of the new species with Sphaeronema alni Turkina & Chizhov, 1986 and placed these two species sister to the rest of Criconematina.  相似文献   

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