New Disease Reports (2010) 22, 23. [http://dx.doi.org/10.5197/j.2044-0588.2010.022.023]
Get pdf (342 KB)

First report of Hirschmanniella gracilis in the UK causing necrosis to roots of tall fescue

T. Prior 1*, S. Hockland 1, R. Lawson 1 and G. Karssen 2

*thomas.prior@fera.gsi.gov.uk

Show affiliations

Published: 13 Oct 2010

In July 2009, the obligate migratory endoparasitic nematode Hirschmanniella gracilis (de Man, 1880) Luc & Goodey, 1964 was found parasitising roots of tall fescue (Festuca arundinacea Schreb.) collected from a riverbank, in the grounds of Castle Howard, York, UK (54.1236°N 0.9165°W). Symptoms of infestation included large necrotic lesions and stunting of roots. This is a new UK record for this genus, in which 37 of the 38 valid species (Sturhan & Hallmann, 2010) are listed in Annex IAI of Council Directive 2000/29/EC. This population has regularly areolated outer bands of the lateral field with occasional commissures present between inner incisures. The subventral pharyngeal glands end in a narrow extension. The shape of tail terminus and length of post anal intestinal sac were variable.Morphometrics of adult females were within reported ranges and are summarised thus (n = 9): L = 2.2 ± 0.1 (2.1-2.3) mm, a = 67.0 ± 5.2 (54.6-74.0), c = 17.8 ± 1.1 (15.6-19.0), c' = 5.4 ± 0.5 (4.8-6.7), V = 52.5 ± 1.7 (49.8-54.8), stylet = 22.5 ± 0.3 (22.1-22.8) μm, tail = 123 ± 12.1 (108-146) μm.

Specimens were preserved in TAF, processed to glycerol (Hooper, 1986) and deposited as voucher specimens in The Food and Environment Research Agency nematode collection.

Figure1+
Figure 1: Roots of Festuca arundinacea showing necrosis caused by parasitism by Hirschmanniella gracilis. (Scale bars: A = 20 mm; B = 5 mm).
Figure 1: Roots of Festuca arundinacea showing necrosis caused by parasitism by Hirschmanniella gracilis. (Scale bars: A = 20 mm; B = 5 mm).
Figure2+
Figure 2: Hirschmanniella gracilis ex. UK. A: anterior region; B: lateral field at mid-body; C: post-anal intestinal sac; D: posterior tail region (Bars: A, B, C, D = 20 μm).
Figure 2: Hirschmanniella gracilis ex. UK. A: anterior region; B: lateral field at mid-body; C: post-anal intestinal sac; D: posterior tail region (Bars: A, B, C, D = 20 μm).

References

  1. Sturhan D, Hallmann J, 2010. The genus Hirschmanniella (Tylenchida: Pratylenchidae) in Europe, with description of H. halophila sp. n. from Germany and notes on H. caudacrena. Nematology (in press).
  2. Hooper, DJ, 1986. Handling, fixing, staining and mounting nematodes. In: outhey JF, ed. Laboratory methods for work with plant and soil nematodes. Sixth Ed:MAFF, London. 59-80.

To cite this report: Prior T, Hockland S, Lawson R, Karssen G, 2010. First report of Hirschmanniella gracilis in the UK causing necrosis to roots of tall fescue. New Disease Reports 22, 23. [http://dx.doi.org/10.5197/j.2044-0588.2010.022.023]

©2010 The Authors