Pterotylenchus cecidogenus

 

Contents

 

Rev 11/30/2022

  Classification Hosts
Morphology and Anatomy Life Cycle
Return to Pterotylenchus Menu Economic Importance Damage
Distribution Management
Return to Anguinidae Menu Feeding  References
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Classification:

      Tylenchida
       Tylenchina
        Tylenchoidea
        Anguinidae

          Pterotylenchus cecidogenus Siddiqi & Lenne, 1984
Type species of the genus
  
  Synonyms:
     
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Morphology and Anatomy:

 

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Females: 

  • Cuticle and subcuticle finely annulated; annules 0.8-1.1 um wide. Lateral fields about 20% of body diam, with four incisures, inner two close together.
  • Cephalic region 5.5-6 um wide by 2-4.5 um high.
  • Stylet with conus about half its length; basal knobs small, rounded,
  • DEGO dorsal gland about 2 um behind stylet base.
  • Esophageal corpus 61-64 um long, with a slight swelling posteriorly where subventral glands open,
  • Isthmus slender, gradually enlarging to an elongate basal bulb; dorsal gland extending for about one body-width over intestine subdorsally and laterally.
  • Nerve ring at middle of isthmus.
  • Excretory pore at about base of isthmus.
  • Deirid just behind level of excretory pore.
  • Vulva about half body diam long; partially covered by large cuticular flaps
  • Crustaformeria of 32-36 cells in four rows followed by a valvula and then a collapsed and empty spermatheca of 24 cells
  • Ovary with oocytes in one or two rows, reaching near to esophageal base.
  • Post-vulval uterine sac 12-25 um long, empty.
  • Rectum shorter than anal body diam.
  • Tail elongate-conoid to a sharply pointed tip, nearly as long as vulva-anus distance

 

Cuticular flaps partly covering the vulva of Pterotylenvhus cecidogenus
Scanning elecron micrograph from Siddiqi and Lenne (1984)
Scale bar = 5um

  

Reported median body size for this species (Length mm; width micrometers; weight micrograms) - Click:

 

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Distribution:

First reported from CIAT in Carimagua, Colombia.

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Economic Importance:

The type host, Desmodium ovaliforlium is a tropical pasture legume.

 

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Feeding:

The nematode forms galls om stems of the host.

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Hosts:

Desmodium ovalifolium is the type host. of P. cecidogenus. Many cultivars produced by CIAT are susceptible, to P. cecidogenus, but several are resistant (Stanton et al., 1990).

For an extensive host range list for this species, click


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Life Cycle:

Males have not been found and sperm has not been seen in the spermatheca.  Reptoduction in the species is probably parthenogenetic.

Ecophysiological Parameters:

For Ecophysiological Parameters for this species, click If species level data are not available, click for genus level parameters
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Damage:

The stem galls are not easily detectable; they form at nodes and  divisions in the stem. The galls cause considerable disruption of the vascular system and eventually to death of the plants.(Siddiqi and Lenne, 1984).


Arrows point to galls caused by Pterotylenvhus cecidogenus on stems of  Desmodium ovalifoliun
Photograph froSiddiqi and Lenne ( 1984)

 

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Management:

Host Plant Resistance, Non-hosts and Crop Rotation alternatives:

For plants reported to have some level of resistance to this species, click
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References:

Fortuner and Maggenti, 1987.  Rev. Nematol. 10(2):163-176.

Siddiqi, M.R. and Lenne, J.M. 1984. Pterotylenchus cecidogenus n. gen., n. sp., a New Stem-gall Nematode Parasitizing Desmodium ovalifolium in Colombia. J. Nematol. 16:62-65

Stanton, J. M., C. A. Garcia and C. Torres. 1990. Resistance and tolerance of Desmodium of ovalifolium to tanton, J. M., C. A. Garcia and C. Torres. 1990. Resistance and tolerance of Desmodium of ovalifolium to PPterotylenchus cecidogenus, the stem gall nematode. Nematologica 36:424-433.

 

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Copyright © 1999 by Howard Ferris.
Revised: November 30, 2022.