One new and three known species of Paratylenchus (Nematoda: Tylenchulidae)
from Manipur, India
M.Pramodini 1 & N. Mohilal2
1,2 Parasitology section, Department of Life Sciences, Manipur
University, Canchipur, Manipur 795003, India
Email: 1 cd_paralab@indiatimes.com, 2 mohilaln@yahoo.co.in
(corresponding author)
Date of
publication 26 March 2009
ISSN 0974-7907
(online) | 0974-7893 (print)
Editor: Anwar L. Bilgrami
Manuscript
details:
Ms # o1744
Received 26
March 2007
Final received
16 August 2008
Finally accepted
16 December 2008
Citation: Pramodini, M. & N. Mohilal (2009). One new and three known species of Paratylenchus (Nematoda:Tylenchulidae) from Manipur, India. Journal of
Threatened Taxa 1(3): 177-179.
Copyright: © M. Pramodini & N. Mohilal 2009.
Creative Commons Attribution 3.0 Unported License. JoTT allows unrestricted use of this article in any medium
for non-profit purposes, reproduction and distribution by providing adequate
credit to the authors and the source of publication.
Acknowledgements: The
authors express sincere thanks to the Head of Department of Life Sciences,
Manipur University for providing laboratory facilities.
For
Tables & Figure – click here
Species
of Paratylenchus Micoletzky,
1922 commonly known as “pin nematodes” are well-known plant pathogens of
various agricultural crops. During a
study of the plant parasitic nematodes associated with plant communities in
Manipur, three known and one new species of Paratylenchus were recovered.
The
nematodes were killed in hot water, fixed in 4% formaldehyde solution,
dehydrated in Glycerine-Alcohol and were mounted in glycerine (Seinhorst 1959, 1962).
Measurements were taken using an ocular micrometer.
Paratylenchus canchicus Mohilal & Dhanachand 2004
Dimensions: Refer Table 1.
Description
Female: Body an open
“C” after fixation. Head not set off,
bluntly rounded, almost hemispherical, cephalic framework weakly developed. Stylet well-developed, styletknobs posteriorly directed. Orifice of dorsal oesophagealgland located at 4.5±0.3 (4-5) µm from styletbase. Excretory pore distinct. Nerve ring located at 65.5±3.5 (60.8-70.4) µm
from the anterior end. Oesophago-intestinal
valve prominent. Ovary outstretched, spermathecaprominent. Tail narrows gradually to a
rounded terminus. Lateral field with
four incisures, equally distinct. Body annules 1.4±0.2 (1.4-1.6) µm wide. Vulva-anus distance 36.5±0.5 (36.0-37.6) µm
or more than one tail length long.
Male: Not found.
Habitat and
locality
Soil
around the roots of Alocasia indica Roxb. from Kakwa, ImphalWest district.
Remarks
The
morphological characters and dimension of the present specimens are in
agreement with those original descriptions and dimensions provided by Mohilal & Dhanachand (2004).
Paratylenchus lepidus Raski 1975
Dimensions: Refer Table 1
Description
Female: Body arcuate ventrally to an open ‘C’ after fixation, slightly
more curved ventrad posterior to vulva. Body cuticle marked by fine transverse striae, about 1.0µm wide. Head rounded, without distinct annules. Stylet knobs
squared-off or slightly posteriorly directed. Dorsal oesophagealgland orifice opens into lumen of oesophagus, about
7±0.8 (6-8) µm behind the basal knobs. Oesophaguscomposed of distinct amalgamated procorpus and corpus
with posteriorly located valve plates, narrow isthmus
and rather rounded basal bulb. Cardia small, round. Nerve
ring surrounds isthmus.
Ovary
mono-prodelphic and outstretched. Spermathecaovoid, prominent, with small spermatozoa. Vulva flaps distinct, large and rounded. Tail tapers gradually to a finely rounded
terminus. Lateral field with four
incisures, inner two slightly less distinct than outer two.
Male: Not found.
Habitat and
locality:
Soil
around the roots of Crotalaria juncea Linn. from Wakha, ImphalEast district, Manipur.
Remarks
The dimensions
and descriptions of the present specimens agree well with those provided by Raski (1975).
Paratylenchus longicaudatus Raski 1975
Dimensions: Refer Table 1
Description:
Female: Body curved ventrally
upon fixation more towards posterior region of vulva. Cuticle with fine
transverse annulations. Body
gradually narrows at anterior end to head which is conoidand truncate. Lip region rounded with
indistinct annules. Lateral fields with four incisures. Stylet slender with slightly posteriorly directed knobs. Orifice of dorsal oesophageal gland located at
5.4±0.4 (5-6) µm from stylet base. Median oesophagealbulb located at 63-88% of total oesophageallength. Nerve ring at 77.6±1.8 (75-80) µm
from anterior end of body encircling the isthmus region. Cardia round,
distinct.
Reproductive
system mono-prodelphic and outstretched. Spermatheca oval shaped, with small spermatozoa. Vulval flaps large
and rounded. Tail
tapering to a finely rounded terminus.
Male: Not found.
Habitat and
localities
Soil
round roots of Cynodon dactylon (L) Urban from Lamka, ChurachandpurDistrict.
Other recorded
habitats and localities of Manipur:
Soil
around roots of 1. Allium hookeri Thw.
from Tronglaobi, BishnupurDistrict; 2. Banana, Musa sp. from Elangbam Leikei, Imphal District, Manipur.
Remarks
The dimensions
and morphological characters of the present populations correspond well with
type specimen described by Raski (1975).
Paratylenchus thysanolus sp. nov.
(Fig. 1)
Material
examined
Holotype: 28 May 2004, on
slide no. PD 295, ParasitologyLaboratory, Life Sciences Department, Manipur University, Canchipur,Imphal.
Paratype: Same
information as above. on slides PD 288 (1-3), PD
295(1-4)
Dimensions: Tables 2 &
3
Etymology: The species is
named after its host plant.
Description
Female: Body ventrally
curved when relaxed, tapering at both ends but become swollen in pre-vulval region. Lateral field with three lines. Lip continuous with body contour, bluntly rounded, not setoff,
almost hemispherical, with a slightly sloping side and a distinct depression at
the oral apperture. Body cuticle marked by fine striae, nearly 1µm apart. Stylet slender with stout prominent knobs, which are backwardly directed. Excretory pore situated in the anterior
region of basal bulb of the oesophagus. Oesophagus typical of the genus. Cardia small and rounded, about 4.2 ±0.3 (3.4-5) µm long.
Reproductive
system mono-prodelphic, ovary outstretched with a
single row. Spermatheca almost spherical and
filled with small spermatozoa. Vulva, a transverse slit with prominently rounded lateral vulvar membrane. Tail tip curved gently ventrad, conoid, narrows gradually to a bluntly rounded terminus.
Male: Body gently
ventrally arcuate after fixation. Body narrows at anterior end to a rounded
head at terminus and posterior from the region of the cloacato an acute terminus. Head sloping with fine annule and sclerotization very
light. Stylet lacking. Oesophagus degenerated.
Excretory pore
distinct, near the nerve ring. Lateral
field with three lines. Body annules very fine. Testis full of large
refractive spermatozoa. Anal sheath prominent and short. Spiculecurved slightly. Tail
straight, narrows to give a very slender conoidoutline with an acute terminus.
Type habitat and
locality
Soil
around the rhizosphere of Thysanolaenamaxima (Roxb.) Kuntz. from Waithou hill, Thoubal district,
Manipur.
Diagnosis and
relationships
Paratylenchus thysanolus sp. nov. is distinct in having
smaller body, bluntly rounded lip with a distinct depression at the oral
aperture and heterogeneous tail shape in between male and female. The new species comes close to P. variatus Jairajpuri, 1982 andP. colbrani Raski,
1975. From P. variatus,
it differs in the body length, stylet length, oesophagus length and shape of tail (L = 0.21-0.31mm, b =
3.6-4.3, stylet = 15-16µm, oesophagus= 55-65µm, tail conoid with variable shape, often digitate or indented in P. variatus). It is distinguished from P. colbrani in its smaller body length, value of ‘a’, ‘b’,
lesser excretory pore length, prorhabdion and lateral
fields (L = 0.28-0.33mm, a = 19-26, b = 3.7-5.4, prorhabdion= 8-10µm, excretory pore = 63-79µm, lateral fields = 4 lines in P. colbrani). The present specimen also differs from P.canchicus, P. longicaudatus and P. lepidus in
its smaller body length, lesser value of ‘a’, smaller length of stylet and oesophagus, much
smaller tail length.
References
Jairajpuri, M.S. (1982). Three new species of nematodes from sugarcane. Revue Nematol. 5(2):
214-246.
Micoletzky, H. (1922). Die freilebenden Erd-Nematoden. Arch.Naturg. Berlin Abt.
Mohilal,
N. & Ch. Dhanachand (2004). Two new species of Paratylenchidae from
Manipur. Uttar Pradesh Journal of Zoology 24(2): 173-177.
Raski, D.J. (1975). Revision of the
Genus Paratylenchus Micoletzky,
1922 and descriptions of new species - part I. Journal of Nematology 7(1): 15 - 34.
Seinhorst, J.W. (1959). A rapid method for the transfer of nematodes from fixative to anhydrous
glycerin. Nematologica 4: 67-69.
Seinhorst,
J.W. (1962). On the killing, fixation and
transferring to glycerine of nematodes. Nematologica 8: 29-32.