Ann.M. A. Bangladesh Kader, I. H. Agric. Mian (2018)and M. 22M. (1) Hossain : 37-49 ISSN 1025-482X (Print)37 2521-5477 (Online) PLANT PARASITIC ASSOCIATED WITH RHIZOSPHERE SOILS OF POTATO IN MUNSHIGONJ AND BAGURA DISTRICTS M. A. Kader1*, I. H. Mian 1 and M. M. Hossain1 Abstract A survey was conducted to identify plant parasitic nematodes and their prevalence associated with rhizosphere soils of potato (Solanum tuberosum) in Munshigonj and Bogra districts of Bangladesh during 2014-2015 and 2015-2016 cropping seasons. A total of 17 under 12 genera were recorded from rhizosphere soils of potato collected from two districts. The identified nematodes in the order of prevalence were Meloidogyne incognita, claytoni, Pratylenchus pratensis, Aphelenchoides sp., Cephalenchus emerginatus, Helicotylenchus dihystera, Hoplolaimus indicus, Tylenchus davainei, Tylenchorhynchus cylindricus, Tylenchorhynchus annulatus, Tylenchorhynchus sacchari, Pratylenchus penetrans, Pratylenchus coffea, , Hirschmaniella sp., Aphelenchus avenae, and Criconemoides sp. having their prevalence of collected soil samples by 35.5, 18.03, 9.59, 9.42, 5.50, 4.22, 3.55, 3.07, 2.90, 2.45, 1.25, 2.19, 2.05, 1.32, 1.21, 1.19 and 1.00%, respectively. The findings indicate that at least 17 species of plant parasitic nematodes are associated with rhizosphere soils of potato in two important potato growing districts of Bangladesh. Keywords: Potato, rhizosphere, plant parasitic nematodes, prevalence.

Introduction Javid (2010) reported that 30% yield loss of Potato (Solanum tuberosum) is a tuber potato due to attack by nematodes in Punjab, crop under the genus Solanum of family Pakistan. According to International Potato Solanaceae. It occupies the fourth place Centre, more than 40 nematode species infect amongst the major food crops including rice, potatoes throughout the world (Jatala, 1986). wheat and maize (Horton et al., 1984). In Hafez and Portenier (2011) reported that more Asia including Bangladesh, potato is mainly than 68 species of nematodes belonging to 24 consumed as a vegetable. So far 57 diseases genera are associated with potatoes in different and disorders of potato have been reported parts of the world. In Bangladesh, reports in Bangladesh (Ali et al., 1990). Among the on nematode disease of potato are limited pests and diseases responsible for low yield of (Choudhury et al., 1981; Timm and Ameen, potato, plant parasitic nematodes play a vital 1960; Sam, 1979; Mian, 1987). Mian (1987) role. Plant parasitic nematodes can reduce conducted a survey during 1984-85 potato both yield and tuber quality of potato (Hooker, growing season and recorded Aphelenchoides 1981). A report from India reveals that plant sp., , Helicotylenchus parasitic nematodes caused yield loss of 32% sp., Meloidogyne sp., M. incognita, M. in potato (Singh and Kumar, 2013). Anwar and javanica, Neotylenchus sp., Pratylenchus

1Department of Plant Pathology, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur 1706, Bangladesh. *Corresponding author: [email protected] 38 Plant Parasitic Nematodes Associated With Rhizosphere Soils coffea, P. penetrans, Rotylenchulus sp., Identification of nematodes Rotylenchus sp., Tylenchorhynchus claytoni Based on recorded morphological and Xiphinema sp. with rhizosphere soils of characteristics and morphometric parameters, potato. So the current survey has been taken to identification was done with the help of to find out the present status of plant parasitic Commonwealth Institute of Helminthology nematodes associated with rhizosphere soils (CIH) Descriptions of Plant parasitic of potato cultivated in Bogra and Munshigonj Nematodes and Pictorial Key by Mai and districts of Bangladesh. Lyon (1975).

Materials and Methods Population of nematode associated with the collected soil samples. Populations Collection of soil samples of nematode species associated with soil The survey was conducted in two extensively samples collected two districts were recorded. potato growing districts of Munshigonj and An amount of 50 ml soil was used for each Bogra districts during potato growing seasons sample (Kimpinski, 1987). Populations of of 2014-2015 and 2015-2016. Soil samples nematodes were determined using calibrated of potato root zone were collected from counting slides. The results were expressed randomly selected 10 fields for each locations in percentage based on total number of soil of Shirajdikhan, Tongibari and Sadar upazilla samples used for nematode extraction. of Munshigonj; Sherpur and Nondigram upazillas of Bogra districts at tuber formig Results and Discussion stage of the crop. The soil samples were collected from 8-10 places of each field at a Identified nematodes and their prevalence depth of 15-20 cm from rhizosphere. All soil During the survey, a total of 17 nematode species viz. Aphelenchoides sp., Aphelenchus avenae, samples of each field were mixed thoroughly Cephalenchus emerginatus, Criconemoides sp., to have a composite sample. About 2.5 kg Ditylenchus dipsaci, Helicotylenchus dihystera, sub-samples were drawn from the composite Hirschmaniella sp., Hoplolaimus indichus, sample. The soil samples were brought to the Meloidogyne incognita, Pratylenchus coffea, laboratory in polythene bag and stored at 10°c P. penetrans, P. pratensis, Tylenchorhynchus for further use. annulatus, T. claytoni, T. cylindricus, T. sacchari, Tylenchus davainei under 12 genera Extraction of nematodes were found to be associated with rhizosphere About 25 working samples drawn from soils of potato in the districts of Bogra and mixture of sub-samples for each districts were Munshigonj (Table 1). The population of used for nematode extraction. Nematodes M. incognita was the maximum percentage were extracted from the soil samples following of soil samples followed by T. claytoni, P. Baermann funnel method and Centrifugal- pratensis, Ahelenchoides sp., C. emerginatus, flotation method (Mian, 1994). Helicotylenchus dihystera and Hoplolaimus M. A. Kader, I. H. Mian and M. M. Hossain 39 indicus. Their average population was 35.5, Morphometric and morphological descriptions 18.03, 9.59, 9.42, 5.50, 4.22, and 3.55%, of identified plant parasitic nematodes of soil samples respectively. On the other Aphelenchoides sp. hand the population of Criconemoides sp. was the lowest followed by A. avenae, The identification of Aphelenchoides sp. Hirschmaniella sp., Ditylenchus dipsaci, was done based on the descriptions of Allen P. coffea, P. penetrans, T. annulatus, T. (1952). Body of adult female was slender, cylindricus and Tylenchus davainei. Their straight or arcuate when relaxed. Length of average prevalence was 1.00, 1.19, 1.21, adult female was 557 µ, a (ratio of body length 1.32, 2.05, 2.19, 2.45, 2.90 and 3.07%, and maximum body width) = 27.85, b (ratio of soil samples respectively. The average of body length and esophageal length) =5.05 prevalence of nematode was 6.68% of soil and c (ratio of body length and tail length) = samples in Munshigonj and 5.89% of soil 15.91. Lip region is smooth, elevated. Stylet samples in Bogra district (Table 1). slender about, 10-11 µ long; basal bulb minute

Table 1. Population of plant parasitic nematodes associated with rhizosphere soils of potato in Bogra and Munshigonj districts of Bangladesh (2014-2015 and 2015-2016) Percentage of soil samples having nematodes Nematode species (Alphabetically) Munshigonj Bogra Average of two districts Aphelenchoides sp. 9.65 7.20 8.42 Aphelenchus avenae 1.13 1.26 1.19 Cephalenchus emerginatus 5.03 5.98 5.50 Criconemoides sp. 2.00 0.00 1.00 Ditylenchus dipsaci 2.65 0.00 1.32 Helicotylenchus dihystera 4.14 4.31 4.22 Hirschmaniella sp. 0.00 2.42 1.21 Hoplolaimus indichus 2.10 5.01 3.55 Meloidogyne incognita 38.20 32.80 35.50 Pratylenchus coffea 2.09 2.01 2.05 P. penetrans 2.05 2.33 2.19 P. pratensis 9.74 7.24 8.59 Tylenchorhynchus annulatus 3.10 1.80 2.45 T. claytoni 19.76 16.30 18.03 T. cylindricus 3.45 2.35 2.90 T. sacchari 1.50 1.00 1.25 Tylenchus davainei 2.90 3.25 3.07 Average of population 6.78 5.89 40 Plant Parasitic Nematodes Associated With Rhizosphere Soils

Table 2. Morphometrics of the identified plant parasitic nematode species

a (ratio of body b (ratio of L (total length c (ratio of body length and body length Identified nematode species of adult female) length and tail maximum body and esophageal (µ) length) width) length) Aphelenchoides sp. 557 27.85 5.05 15.91 Aphelenchus avenae 720-740 31 6 35 Cephalenchus emerginatus 500-580 * * * Criconemoides sp. 506.5 12.65 4.22 16.87 Ditylenchus dipsaci 557 32.46 5.40 11.14 Helicotylenchus dihystera 630-810 30 6 * Hirschmaniella sp. 2100 42 17 23 Hoplolaimus indichus 1104-1202 28.78 8.2 53.82 Meloidogyne incognita * * * * Pratylenchus coffea 450-710 25-35 5-7 17-22 P. penetrans 628 24.80 4.96 20.66 P. pratensis 480-600 24-32 4.6-6.0 16-22 Tylenchorhynchus annulatus 648 28 5.3 14 T. claytoni 680- 750 * * * T. cylindricus 650-990 28-34 4.2-6.0 13-20 T. sacchari 650-730 23.6 4.3 11.8 Tylenchus davainei * * * * *Data were not recorded due to insufficient number of sample but distinct. Esophagous aphelenchoid type. was consulted (Goodey and Hooper, 1965). Esophageal gland elongate, extending over Female body is cylindrical usually with slight intestine. Vulva transverse slit. Ovary single ventral arcuate when killed by heat, widest just anteriorly outstretched. Tail elongate conoid. in front of the vulva. Important morphometrics Adult male has well developed spicule (Plate of adult female are L = 720-740 µ, a = 31, b = 1. a, b). 6, c = 35. Stylet length is 15 µ. Head is bluntly *Prevalence was calculated by the occurrence rounded to flattened and not offset from the of larval stage only and identification was body. Esophagus aphelenchoid type, median done by studying perineal pattern of adult bulb well developed and squarish. Esophageal female. So morphometrics were not taken. lumen of dead nematode is straight. Vulva is a transverse slit. Ovary is monodelphic, Aphelenchus avenae prodelphic and outstretched. Tail is 1.77 µ For identification of Aphelenchus avenae, anal body diameter and tail tip is bluntly CIH description of plant parasitic nematodes rounded (Plate 1.c, d). M. A. Kader, I. H. Mian and M. M. Hossain 41

Cephalenchus emerginatus is tylenchoid type; basal bulb is abutting. Vulva is a transverse slit at 70-72% of body The nematode was identified based on characteristics described by Hooper (1974). from the anterior end. Ovary is monodelphic, Body of adult female is vermiform, relatively prodelphic and outstretched (Plate 1. e, f, g). slender with slight curve ventrally in heat killed specimen. The nematode is smaller in Criconemoides sp. (Ring nematode) size, only 500-580 µm long, narrows only The nematode was identified using the a little anterior but posterior to the vulva it descriptions of Loof (1974). Body of the adult tapers sharply forming a narrow long fine female is short and fusiform, both terminus tail with a pointed terminus. Stylet is well spherical to truncate under light microscope. developed with round knobs. Esophagus Body consists of 92-112 annules. Annules

Plate 1. Microphotographs showing adult female of a) Aphelenchoides sp., b) adult male Aphelenchoides sp.; c) adult female of Aphelenchus avenae, d) Anterior region of Aphelenchus avenae; e) adult female of Cephalenchus emerginatus, f) anterior and g) posterior region of C. emerginatus. 42 Plant Parasitic Nematodes Associated With Rhizosphere Soils course, retrose, margin irregularly serrated. bulb overlaps anterior part of intestine from Average length of adult female is 506.5 ventral side. Ovary is didelphic, amphidelphic µm, a=12.65, b=4.22 and c=16.87. Stylet and outstretched. Vulva is transverse slit like strong, with anchor shaped base. Esophagus at 65-70% of the body from anterior. Tail is criconematoid type. Excretory pore is just short, conoid with a narrow terminus called behind the esophageal base. Vulva is a mucron (Plate 2. g, h, i). transverse slit. Ovary single, reaches beyond the esophagous base. Anus is very indistinct. Hirschmaniella sp. Tail conoid, terminus truncate to broadly For identification of Hirschmaniella sp. rounded (Plate 2. a, b, c). descriptions of Luc and Goodey (1964) were consulted. Body of adult female is elongate, Ditylenchus dipsaci (Stem nematode) straight or ventrally curved when heat relaxed. The nematode was identified consulting the The length of adult female is 2100µ, a = 42, b descriptions of Evans and Fisher (1970). = 17, and c = 23. Labial framework heavily Body of adult female is vermiform with slight sclerotized. Stylet is long (over 40 µ), with ventral curvature when killed by heat. The rounded basal knobs. Median esophageal length of adult female is 557 µ, a= 32.46, bulb ovoid; esophageal glands elongate, b = 5.40 and c = 11.14. Lip region low and overlapping intestine ventrally or latero- flattened. Labial framework moderately ventrally. Two genital branches. Tail elongate- developed; stylet 10-14 µ long with distinct conoid (Plate 2. j, k, l). basal knobs. Median bulb fusiform, isthmus narrow; basal bulb overlaps the intestine. Hoplolaimus indicus (Lance nematode) Ovary is single, prodelphic; vulva distinct, Body of adult female is elongate-cylindrical, anteriorly outstretched. Tail is conoid with tapering towards both ends. Length of the body slight ventral curvature with a narrow rounded is 1104-1202 µ, a, b and c values are 28.78, 8.2 terminus (Plate 2. d, e, f). and 53.82, respectively. Cephalic framework strongly sclerotized. Head is distinctly set off, Helicotylenchus dihystera (Spiral nematode) 10.1 µ in height. Stylet massive, 35 µ long Identification of spiral nematodes upto with anteriorly projected knobs. Esophagus species level was done by satisfying the tylenchoid, 131µ long. Esophageal gland characteristic features described by Siddiqi overlaps the intestine dorsally and laterally. (1972). Body of adult female is spiral, length Ovary two, outstretched. Vulva is conspicuous, is 630-810 µ, a=30, b = 6. The body shape transverse slit, 10.0-12.0 µ wide with two becomes coiled after death due to heat. Lip distinct lips. In female, tail short, 22.1-22.4 µ region hemispherical, cephalic framework long, 25.5-26.5 µ wide at anal body, with round is conspicuous, head slightly set off and terminus. In male, tail conoid, enveloped by conoid. Stylet is well developed. Dorsal bursa. Anus is circular, 2.0-2.2 µ diameter. All esophageal gland orifice (DGO) is situated morphological characters described above are at less than half of spear length behind the similar as described by Handoo and Golden knob. Esophagus is tylenchoid type. Basal (1992) (Plate 3.a, b). M. A. Kader, I. H. Mian and M. M. Hossain 43

Plate 2. Microphotographs showing a) adult female, b) anterior and c) posterior region of Criconemoides sp.; d) adult female, e) anterior and f) posterior region of Ditylenchus dipsaci; g) adult female, h) anterior and i) posterior region of Helicotylenchus dihystera; j) adult female, k) anterior and l) posterior region of Hirschmaniella sp. 44 Plant Parasitic Nematodes Associated With Rhizosphere Soils

Meloidogyne incognita (Root- knot nematode) slender, almost straight when killed by gentle The morphological features of head, anterior heat and 628 µ long; a = 24.80, b = 4.96 and body, labial disc of larvae and perineal c =20.66. Basal knob of stylet is broadly pattern were the same as described for the rounded, sometimes cupped anteriorly. species (Eisenback, 2010). The head of Esophageal lumen is not straight, median larva is not offset, truncate cone shape in bulb is broadly oval in shape. Basal bulb lateral view and sub-hemispherical in dorso- overlaps the intestine ventrally. Excretory ventral view. Spear knob prominent and pore is located at just anterior to the esophago- rounded. Esophagus overlaps intestine. Tail intestinal junction. Ovary is monodelphic, is tapering to subacute terminus. Perineal prodelphic. The vulva is transverse and about pattern with striae closely spaced, very wavy 75% from the head. Tail generally rounded to zigzag especially dorsally and laterally. and smooth (Plate 3. j, k, l). Morphological characteristics of larvae (Plate 3. f, g, h) Perennial pattern were Pratylenchus pratensis (Lesion nematode) studied (Plate 3. i) and compared with the The species P. pratensis was identified description of Barker et al., (1985) confirmed consulting the description of Loof (1991). the species. Female body is vermiform, more or less Pratylenchus coffea (Lesion nematode) straight when killed by heat or on relax and 480-600 µ long; a = 24-32, b = 4.6-6.0 and The species of lesion nematode was identified c =16-22. Stylet has three well separated consulting the description of Loof (1991). knobs. Median bulb is broadly oval in shape. Female body is vermiform, more or less Basal bulb overlaps the intestine ventrally. straight on relaxed body posture and 450-710 Ovary is monodelphic, prodelphic. The µ long; a = 25-35, b = 5-7 and c =17-22. Basal knob of stylet is round to oblong. Esophageal vulva is transverse slit and about 72-77% lumen is not straight, median bulb is broadly from the head. Tail with 25-28 annules and oval in shape. Basal bulb overlaps the intestine the terminus is slightly curve ventrally (Plate ventrally. Excretory pore is located at just 3. m, n). anterior to the esophago-intestinal junction. Ovary is monodelphic and prodelphic. The Tylenchorhynchus annulatus (Stunt nematode) vulva is transversely slit and about 72-77% The species of stunt nematode was identified from the head. Tail 1.5-2.0 times anal body consulting the descriptions of Golden (1971). width in adult female; terminus truncate, Adult female body is ventrally arcuate, irregularly crenate or indented (Plate 3. c, d, e). distinctly annulated by deep striae. Body length of female is 648 µ, a =28, b =5.3 and Pratylenchus penetrans (Lesion nematode) c=14. Stylet is 17-18 µ long, slender with The species of lesion nematode was identified round basal knobs. DGO is obscure. Median consulting the description of Loof (1991). bulb is oval, its valve located halfway along Female body is vermiform, moderately esophagus. Isthmus is long and narrow, M. A. Kader, I. H. Mian and M. M. Hossain 45

Plate 3. Microphotographs showing adult a) female and b) male of Hoplolaimus indicus; c) adult female, d) Anterior and e) posterior region of Pratylenchus coffea; f) larva, g) anterior, h) posterior region and i) perineal pattern of Meloidogyne incognita; j)adult female k) anterior region and l) posterior region of Pratylenchus penetrans; m) adult female and n) adult male of Pratylenchus pratensis. 46 Plant Parasitic Nematodes Associated With Rhizosphere Soils terminal bulb pyriform, with conspicuous half body width long. Ovary is didelphic, dorsal gland nucleus. Vulva transverse, amphidelphic, outstretched. Tail is elongate- vagina straight less than one-half body width conoid, with unstriated, smoothly rounded long. Ovary is didelphic, amphidelphic, distal end (Plate 4. f, g, h, i). outstretched. Tail is sub cylindrical, almost straight to slightly arcuate ventrally (Plate 4. Tylenchorhynchus sacchari (Stunt nematode) a, b, c, d). Identification of the nematode species was done consulting descriptions by Sivakumar Tylenchorhynchus claytoni (Stunt nematode) and Muthukrishnan (1983). Body of adult Descriptions of the species used for female is straight to slightly arcuate in fixed identification by Loof (1960) were also used specimen, tapering at both ends. Length of in the present investigation to identify the the adult female is 650-730 µ, a = 23.6, b nematode. Adult female body is cylindrical, =4.3 and c =11.8. Stylet well developed, with with weakly curve ventrally when relaxed. large anteriorly cupped basal knobs. Median Body length is 680- 750 µ with coarse bulb is large, oval; basal bulb elongate transverse striae. Lateral field consists of 4 pyriform. Ovary is didelphic, amphidelphic, longitudinal lines. Stylet is slender with round outstretched. Tail shape is clavate having 18- basal knobs. Median bulb is oval; its valve 22 annules, tail terminus hemispherical with located halfway along esophagus, terminal smooth annulation (Plate 4. j, k, l). bulb pyriform, with conspicuous dorsal gland nucleus. Vagina is less than one-half body Tylenchus davainei width long. Ovary is didelphic, amphidelphic, Tylenchus davainei was identified using the outstretched. Rectum is about one-half the description of Andrassy (1979). It is a small anal body width. Tail is tapering towards end nematode. Cephalic framework is moderately with smooth terminus (Plate 4. e). sclerotized. Head region slightly set off from the body. Stylet with distinct knobs. Median Tylenchorhynchus cylindricus (Stunt nematode) bulb is prominent with vulvular apparatus. Descriptions of the species by Allen (1955) Basal bulb is abutting with cardia over the for identification were also used in the present intestine. Ovary is monodelphic prodelphic. investigation to identify the nematode. Body Vulva lip is raised and well posterior to middle of adult female is straight to slightly arcuate of body. Tail is filiform with pointed terminus in fixed specimen, tapering at both ends. (Plate 4. m, n, o). Length of the adult female is 650-990 µ, a = Available reports from different potato growing 28-34, b =4.2-6.0 and c =13-20. Stylet well countries of the world revealed that potato is developed, with large anteriorly cupped basal attacked by large number of plant parasitic knobs. Median bulb is large, oval, basal bulb nematodes (Jatala, 1986; Hafez and Portenier, elongate pyriform. Vagina is less than one- 2011 and Soomro et al., 2002). As a major M. A. Kader, I. H. Mian and M. M. Hossain 47

Plate 4. Microphotographs showing morphology of a) adult female, b) adult male, c) anterior and d) posterior region of Tylenchorhynchus annulatus; e) adult female of Tylenchorhuynchus claytoni ; f) adult female, g) anterior, h) posterior region and i) vulva of Tylenchorhynchus cylindricus; j) adult female k) anterior and l) posterior region of Tylenchorhuynchus sacchari ; m) adult female n) anterior and o) posterior region of Tylenchus davainei. 48 Plant Parasitic Nematodes Associated With Rhizosphere Soils nematode pest of potato, Meloidogyne incognita, potato is Meloidogyne incognita. Further study Pratylenchus penetrans, Pratylenchus coffea, may be undertaken to determine the effects of Pratylenchus pratensis and Ditylenchus dipsaci these nematodes on yield of potato. were identified in this study. References In Bangladesh, Aphelenchoides sp., Ali, M. S., Bari, M. A. and Khan, A. L. 1990. Ditylenchus destructor, H. dihystera, Pathological constraints of seed potato. Longidorus sp., M. incognita, M. arenaria, production in Bangladesh. In: Proc. seed M. javanica, Meloidogyne sp., Neotylenchus potato in Bangladesh, BADC. 187-199 P. sp. Pratylenchus coffea, P. penetrans, Allen, M. W. 1952. Descriptions of plant parasitic Rotylenchulus sp., Rotylenchus sp. Trichodorus nematodes: Aphelenchoides sp. Proc. Helminth. Soc. Wash. 19: 108-120. sp. T. claytoni and Xiphinema sp. have been found to be associated with rhizosphere soils and Allen, M. W. 1955. A review of the genus Tylenchorhynchus. Univ. Calif. Publns. root samples of potato (Mian 1986). Findings Zool. 61(3): 129-165. of the present study reveal that A. avenae, C. Andrassy, I. 1979. The genera and species of emerginatus, Criconemoides sp., Ditylenchus the family Tylenchidae Orley 1880 dipsaci, Hirschmaniella sp., H. indicus, P. (Nematoda). The genus Tylenchus Bastian, pratensis, T. annulatus, T. cylindricus, T. 1865. Acta zool. Hung. 25: 1-33. sacchari and Tylenchus davainei are also Anwar, S. A. and N. Javid. 2010. Meloidogyne associated with soil of potato fields. This is incognita infecting dahlia. Pakistan J. the first report to identify these nematodes Zool. 42: 348-350. associated with potato field soil collected from Barker, K. R., C. C. Carter and J. N. Sasser. 1985. two different district of the country. However, An advanced treatise on Meloidogyne. the nematodes have been reported as pests of Volume II. North Carolina State University Graphics, Raleigh, North Carolina: potato from different countries of the world Methodology. A cooperative publication (Hafez and Portenier, 2011). of the Department of Plant Pathology and Conclusion the United States Agency for International Development; 1985. 69-77 P. Potato grown in Bangladesh is attacked by at Choudhury, B. C., M. C. Isabel and M. O. Hoque. least 17 species of plant parasitic nematodes. 1981. A preliminary investigation on plant These are Meloidogyne incognita, Hoplolaimus parasitic nematodes associated with banana indicus, Helicotylenchus dihystera, in Joydebpur, Bangladesh. Bangladesh Hort. 9: 41-44. Pratylenchus pratensis, Pratylenchus coffea, Pratylenchus penetrans, Tylenchorhynchus Eisenback, J. D. 2010. A new technique for photographing perineal patterns of root- claytoni, Tylenchorhynchus annulatus, knot nematodes. J. Nematol. 42(1): 33-34. Tylenchorhynchus cylindricus, Cephalenchus Evans, A. A. F. and J. M. Fisher. 1970. The emerginatus, Tylenchus davainei, excretory systems of three Ditylenchus spp. Hirschmaniella sp., Ditylenchus dipsaci, J. Nematol. 2(3): 260-264. Tylenchorhynchus sacchari, Criconemoides Golden, A. M. 1971. Plant parasitic nematodes. sp., Aphelenchus avenae and Aphelenchoides New york Academic press, Inc., 1. vol. Pp. sp. The most prevalent nematode parasite of 191-232. M. A. Kader, I. H. Mian and M. M. Hossain 49

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