Literature review: Impact of Chilean needle grass ... - Weeds Australia

Nematodes of grasses and grasslands
Nematodes (Phylum Nematoda) constitute a vast, poorly explored taxon and are “the most abundant multicellular animals on
earth” (Baldwin et al. 2004 p. 84). As many as 500,000 species have been predicted to exist, of which only 10,000 were known
in 1951 (Meglitsch 1972). Most are entirely free-living in soil, water, etc. and a comparitively small proportion are plant
parasites (Baldwin et al. 2004). Many of the parasitic groups have free-living stages and there is a full suite of intermediate
lifestyles from fully sedentary ecto- or endoparasitism to migratory endoparasitism (Siddiqi 1986, Baldwin et al. 2004). Many of
the plant parasitic nematodes are ecto- or endo-parastites of grasses. Secretion products from plant parasistic species promote
plant pathologies including nurse cells, root-knots and cysts specific to particular taxa, while some groups transmit viruses to
their hosts (Baldwin et al. 2004). The order Tylenchida, commonly called plant nematodes, is the largest and most economically
important group of plant parasites, and its members damage all plant organs including seeds, flowers and especially roots
(Siddiqi 1986). However the orders Dorylaimida and Triplonchida also include plant parasites (Baldwin et al. 2004).
Johnston (1938) recorded numerous species from unidentified grasses in Australia, along with species that attack sugar cane and
cereals, but no records from native grasses. McLeod et al. (1994) recorded 42 taxa from unspecified grass or grasses in Australia
and listed the nematode species found on a wide range of other grasses in Australia.
In the Stipeae, Anguina sp. is recorded from Austrostipa drummondii (Steud.) Jacobs & Everett and A. nitida (Summerh. & C.E.
Hubb.) Jacobs & Everett in Victoria, A. trichophylla (Benth.) Jacobs & Everett in Western Australia and from “Stipa” sp. in
NSW, Neodolichodorus adelaidensis and Xiphinema monhystereum are recorded from “Stipa” sp. in South Australia, and
Pratylenchus neglectus is recorded from Austrostipa trichophylla (Benth.) Jacobs & Everett in Queensland (McLeod et al.
1994).
No species were known from Themeda triandra in south-eastern Australia, but 19 species have been found associated with the
plant in Queensland (McLeod et al. 1994). Radopholus intermedius Colbran was described from material taken from around the
roots of Allocasuarina torulosa (Aiton) L. Johnson and T. triandra, and R. laevis Colbran has also been found in this situation
(Colbran 1971). The genus Radopholus Thorne contains 22 root endoparasitic species all but one of which are indigenous to
Australia (Siddiqi 1986).
Table A2.2. Literature records of the hosts of grass-inhabiting Nematoda recorded in south-eastern Australia. Grasses included
are inhabitants or probably occur in temperate south eastern Australian grasslands. South-eastern Australia excludes Queensland.
Nematodes recorded from unspecified grass or grasses are not included. The list is indicative only, since a large proportion of the
distribution records are not from grasslands. All data from McLeod et al. (1994). Nematode family assignment from Siddiqi
(1986).
Grass Nematode Family Distribution
*Agrostis capillaris Belonolaimus sp. Dolichodoridae NSW
Helicotylenchus dihystera Tylenchidae NSW
*Agrostis stoloniferea Paratrichodorus lobatus ? NSW
Paratylenchus nanus Paratylenchidae NSW
*Avena fatua Paratylenchus sp. Paratylenchidae Vic
*Avena sativa Ditylenchus dipsaci Anguinidae SA
Heterodera avenae Heteroderidae NSW, SA, Vic
Meloidogyne javanica Meloidogynidae NSW
Paratylenchus neglectus Paratylenchidae SA, Vic
Pratylenchus thornei Pratylenchidae SA
Pratylenchus sp. Pratylenchidae Vic
Scutellonema brachyurum Hoplolaimidae NSW
Austrodanthonia caespitosa Paralongidorus sacchari ? SA
Xiphinema monohysterum Neotylenchidae SA
Austrodanthonia setacea Paratylenchus sp. Paratylenchidae SA
Austrostipa nitida Anguina sp. Anguinidae Vic
*Bromus catharticus Ditylenchus dipsaci Anguinidae NSW
*Bromus sp. Meloidogyne sp. Meloidogynidae SA
*Chloris gayana Meloidogyne incognita Meloidogynidae NSW
*Cynodon dactylon Belonolaimus lolii Dolichodoridae NSW
Criconema mutabilie Criconematidae SA
Ditylenchus intermedius Anguinidae NSW
Helicotylenchus dihystera Tylenchidae NSW
Hemicriconemoides minor Criconematidae Vic
Hemicycliophora labiata Hemicycliophoridae NSW, SA
Hemicycliophora saueri Hemicycliophoridae Vic
Hemicyliophora truncata Hemicycliophoridae NSW
Heterodera graminis Heteroderidae NSW
Heterodera sp. Heteroderidae NSW
Macroposthonis sp. Criocnematidae Vic
Morulaimus whitei Dolichodoridae Vic
Paralongidorus eucalypti ? Vic
Paratrichodorus lobatus ? NSW, SA
Paratrichodorus minor ? NSW
Rotylenchus brevicaudatus Hoplolaimidae NSW
Scutellonema brachyurum Hoplolaimidae NSW, SA
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