Molecular identification of stipoid grasses

Project summary

Stipoid grasses belong to the tribe Stipeae, which includes pasture grasses and weeds in genera such as Austrostipa, Nassella,Piptochaetium and Stipa. In the absence of flowers, stipoid grasses are often difficult to identify. This may present a serious problem for people needing to quickly identify these grasses, such as weed enforcement officers who require accurate identifications, especially for declared noxious weeds. Some invasive stipoid grasses have already become commercially devastating weeds in Australia (e.g., Nassella neesiana and N. trichotoma).

Staff at Royal Botanic Gardens (RBG) Melbourne, working in collaboration with the Victorian Department of Environment and Primary Industries, are developing molecular identification methods for native and introduced stipoid grasses in Australia. This includes the compilation of a DNA sequence reference database that can be queried for future identification needs.

Identification using DNA sequence data is often referred to as 'DNA barcoding'. An advantage of DNA barcoding over traditional morphological methods is that DNA can usually be collected from any part of an unknown plant: leaves, roots, stems or even seeds.

Authoritatively identified, vouchered reference material is an essential requirement for developing molecular identification techniques. Well characterised material allows taxon identification to be tied to a verifiable herbarium specimen – information that is not always associated with DNA sequence data from public online sequence databases. The National Herbarium of Victoria (MEL) at RBG Melbourne houses a large collection of grass samples, identified by authorities in grass taxonomy. We are grateful for the assistance of grass taxonomists and herbaria worldwide who have provided access to well verified herbarium specimens, particularly of taxa that are invasive in Australia.

Project team

  • David Cantrill (Royal Botanic Gardens Melbourne)
  • Daniel Murphy (Royal Botanic Gardens Melbourne)
  • Gareth Holmes (Royal Botanic Gardens Melbourne)
  • Val Stajsic (Royal Botanic Gardens Melbourne)
  • Neville Walsh (Royal Botanic Gardens Melbourne)
  • Aaron Dodd (Department of Environment and Primary Industries, Victoria)
  • Charles Grech (Department of Environment and Primary Industries, Victoria)
  • David McLaren (Department of Environment and Primary Industries, Victoria)

Publications

Syme, A.E., Udovicic, F., Stajsic, V. and Murphy, D.J. (2013). A test of sequence-matching algorithms for a DNA barcode database of invasive grasses. DNA Barcodes 2013, 19–26.

Syme, A.E., Murphy, D.J., Holmes, G.D., Gardner, S., Fowler, R. and Cantrill, D.C. (2012). An expanded phylogenetic analysis of Austrostipa (Poaceae: Stipeae) to test infrageneric relationships. Australian Systematic Botany 25, 1–10.