Characterization of commercial cultivars and naturalized genotypes of Stenotaphrum secundatum (Walter) Kuntze in Australia

Stenotaphrum secundatum (Walter) Kuntze, known as "St Augustinegrass" in the USA and "buffalo grass" in Australia, is a widely used turfgrass species in subtropical and warm temperate regions of the world. Throughout its range, S. secundatum encompasses a great deal of genetic diversity, which can be exploited in future breeding programs. To understand better the range of genetic variation in Australia, morphological-agronomic classification and DNA profiling were used to characterize and group 17 commercial cultivars and 18 naturalized genotypes collected from across Australia. Historically, there have been two main sources of S. secundatum in Austalia: one a reputedly sterile triploid race (the so-called Cape deme) from South Africa now represented by the Australian Common group naturalized in all Australian states; and the other a "normal" fertile diploid race naturalized north from Sydney along the NSW coast, which is referred to here as the Australian Commercial group because it has been the source of most of the new cultivars recently developed in Australia. Over the past 30 years, some US cultivars have also been introduced and commercialized; these are again "normal" fertile diploids, but from a group distinclty different from the Australian Commercial genotypes as shown by both DNA analysis and grouping based on 28 morphological-agronomic characteristics. The implications for future breeding within S. secundatum in Australia are discussed.

A review of the biology, ecology, distribution and control of Mozambique tilapia, Oreochromis mossambicus (Peters 1852) (Pisces: Cichlidae) with particular emphasis on invasive Australian populations

Oreochromis mossambicus (Peters 1852) are native to the eastward flowing rivers of central and southern Africa but from the early 1930s they have been widely distributed around the world for aquaculture and for biological control of weeds and insects. While O. mossambicus are now not commonly used as an aquaculture species, the biological traits that made them a popular culture species including tolerance to wide ranging ecological conditions, generalist dietary requirements and rapid reproduction with maternal care have also made them a 'model' invader. Self-sustaining populations now exist in almost every region to which they have been imported. In Australia, since their introduction in the 1970s, O. mossambicus have become established in catchments along the east and west coasts and have the potential to colonise other adjacent drainages. It is thought that intentional translocations are likely to be the most significant factor in their spread in Australia. The ecological and physical tolerances and preferences, reproductive behaviour, hybridization and the high degree of plasticity in the life history traits of O. mossambicus are reviewed. Impacts of O. mossambicus on natural ecosystems including competitive displacement of native species, habitat alteration, predation and as a vector in the spread of diseases are discussed. Potential methods for eradicating or controlling invasive populations of O. mossambicus including physical removal, piscicides, screens, environmental management and genetic technologies are outlined.

Analysis of Crude Protein and Allergen Abundance in Peanuts (Arachis hypogaea cv. Walter) from Three Growing Regions in Australia

The effects of plant growth conditions on concentrations of proteins, including allergens, in peanut (Arachis hypogaea L.) kernels are largely unknown. Peanuts (cv. Walter) were grown at five sites (Taabinga, Redvale, Childers, Bundaberg, and Kairi) covering three commercial growing regions in Queensland, Australia. Differences in temperature, rainfall, and solar radiation during the growing season were evaluated. Kernel yield varied from 2.3 t/ha (Kairi) to 3.9 t/ha (Childers), probably due to differences in solar radiation. Crude protein appeared to vary only between Kairi and Childers, whereas Ara h 1 and 2 concentrations were similar in all locations. 2D-DIGE revealed significant differences in spot volumes for only two minor protein spots from peanuts grown in the five locations. Western blotting using peanut-allergic serum revealed no qualitative differences in recognition of antigens. It was concluded that peanuts grown in different growing regions in Queensland, Australia, had similar protein compositions and therefore were unlikely to show differences in allergenicity.