2009 two basic genotypic groups o s secundatum exist

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farms” (Loch et al., 2009). Two basic genotypic groups of S. secundatumexist in Australia, the sterile triploid Cape deme (common buffalo grass) and a normal fertile diploid race (established along the mid-north coast of NSW). Most of the development of commercial cultivars of buffalo grass has beenbased on selections from the latter group (Loch et al., 2009). Historically, buffalo grass used for household and public lawns in Australia was propagated from runners of the introduced common buffalo grass. Shademaster was the first soft-leaf cultivar developed and commercialised in Australia, released in the 1990s (Buffalo Lawn Care). It was selected from a population of normal S. secundatumin the lower Hunter Valley of NSW (Loch et al., 2009). Many later cultivars either had Shademaster as parent material or were similarly selected from naturalised plant populations in the Hunter or Hawkesbury regions of NSW (Loch et al., 2009).15
The biology of Stenotaphrum secundatum (Walt.) Kuntze — Buffalo grassOffice of the Gene Technology RegulatorImprovements of buffalo grass in Australia have targeted superior physical characteristics such as colour and greater leaf to stem ratio. Loch et al. (2009) concluded that future commercial development of the species should focus on the capacity of buffalo grass to tolerate wear, management (especially mowing), varying levels of shade, water use and herbicide tolerance. The authors also identified the future challenge of developing varieties that meet the conflicting demands of turf producers and turf consumers. Producers prefer aggressively growing types that can be harvested frequently, whereas turf managers and home gardeners prefer less spreading types that require less mowing. Some USA cultivars of S. secundatumhave become established in Australia. These have been developed from “normal” diploid types in the USA, and show distinctly different DNA profiles compared with Australian-derived "normal" types (Loch et al., 2009). As with commercial cultivars in Australia, commercial cultivars in the USA have historically been produced by clonal propagation.Breeding between different races of S. secundatumhas been impeded by differences in ploidy levels.The perennial nature of S. secundatumhas also limited breeding efforts, as long-term field evaluationis required to ensure exposure to environmental and biotic problems and for the plant to exhibit tolerances or sensitivities to these factors (Busey, 1995). There has been limited or no public expenditure on the improvement of S. secundatum in the US, compared with other turf grasses, as the species is predominantly used for lawns rather than golf or sports turf (Busey, 2003b; Cakir et al., 2017).Recent characterisation studies highlight the benefits of gaining more knowledge of genetic relationships between groups and types of S. secundatum, in order to more effectively and strategically use germplasm across ploidy levels for cultivar development (Milla-Lewis et al., 2013; Mulkey et al., 2014).2.4.2 Genetic modificationA number of turf grass species, particularly C3 plants but also the C4 plants

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