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As Australian fruit and vegetable breeding programmes by public research institutions are progressively downsized or curtailed, new cultivars for production horticulture are increasingly being sourced from breeding programmes of overseas companies. Typically, such cultivars are purchased initially on the basis of their description and performance overseas, together with price. However, there is a significant risk that these could fail under Australian conditions and markets: for example, disease resistance claims may not hold up when exposed to different races of the causal organism in Australia; flavour and visual attributes may not suit Australian consumers; some cultivars may not prove as productive as found overseas; and unforeseen genetic weaknesses may become apparent. This paper reports results of irrigated field trials conducted in south-east Queensland over 2 years using melon (Cucumis melo) cultivars sourced from seed companies in Taiwan, Vietnam, China and USA. A preliminary screening trial in year 1 was used to shortlist a smaller number of cultivars for more detailed trials in year 2 to assess their potential productivity for commercial use and their novelty appeal for non-commercial markets.

Phytophagous mites were first identified as a problem in warm-season turfgrasses in Australia around 80 years ago. In production turfgrass fields, slower growth and weakening of sod strength by mites can cause serious commercial losses through breakage of harvested rolls. Elsewhere, mite infestation is associated with poor wear resistance coupled with very slow recovery of turf on playing fields, thereby reducing the usage that is possible on such fields. At the same time, knowledge about turfgrass mites is lacking: specifically, which mite group/species is/are causing damage and to which turfgrass species. There has long been an underlying assumption, based mainly on overseas literature, that mites of the family Eriophyidae are the main cause of the distorted growth symptoms frequently seen and attributed to mite damage. During the 2010/11 growing season, an Australia-wide survey was conducted, sampling seven warm-season turfgrass genera to determine the mites present in each case. This paper reports the results of that survey, together with data from more recent mite infestations sampled during the subsequent threeyear period. Based on their frequency of occurrence, tenuipalpid mites from the genus Dolichotetranychus appear to be at least as important as eriophyoid mites on Cynodon spp.; Dolichotetranychus mites were also recorded from two survey samples of Zoysia spp. but not in subsequent sampling. Eriophyoid mites of the genus Aceria were found on Cynodon spp., with possibly a second species on Zoysia species. A number of mixed tenuipalpid/eriophyoid populations have also been found on Cynodon species. A Steneotarsonemus species (Tarsonemidae) was found associated with Pennisetum clandestinum. Grass-webbing tetranychid mites (Oligonychus spp.) also occasionally affect a wide range of warm-season turf and other grasses non-selectively.

The modern Australian turfgrass industry developed from the period between World Wars I and II, in response to increasing urbanisation and construction of more sophisticated, higher quality sporting facilities. Its development intensified from the 1960s onwards with selection of the first widely used local varieties and import of new US-bred greens hybrids. This timetable, together with its underlying drivers, is similar to that in other developed countries in North America, Europe and southern Africa. However, supporting turfgrass education and research have developed very differently in Australia. Vocational greenkeeper training started in the 1940s with instructors from the NSW agriculture department, but moved into the Technical and Further Education (TAFE) system in the 1950s and has developed from there in all states. University-based training at post-graduate, and now undergraduate, level has become more available in the past 20-30 years, but is still a relatively small component within the overall tertiary education sector for agriculture and environmental science. In Australia, food-and fibre-based industries have been backed by strong, stable government research for over 100 years, in contrast to turfgrass (and lifestyle horticulture generally) where formal research support from state government departments has been limited, sporadic and lacked continuity. University research initiated in the past 20-30 years remains limited but is increasing in response to industry funding. Research into specific turfgrass problems has also been conducted over the past 50-80 years by private industry-funded providers, which have come and gone at regular intervals. Australia lacks a numerically strong nucleus of technically competent scientists and educators to provide independent advice to the turfgrass industry. The implications of this in terms of the quality of information accessed by practitioners are explored.

The lifestyle horticulture industry can best be described as a “living green industry”. It involves the production, sale, management and maintenance of plants used for environmental, recreational and leisure purposes. In Australia, this specialised sector of horticulture has become one of the more profitable and rapidly growing primary industries since World War II. This paper discusses the significance of the Australian lifestyle horticulture industry in terms of its environmental, aesthetic, social and recreational values in the urban environment where 87% of Australians live, work and play, as well as the impact of these commodities and services on the health and well-being of those communities. The industry also generates substantial direct and indirect economic benefits. However, the few available statistics from which the size of the industry can be assessed are, at best, unreliable. While these do indicate that the lifestyle horticulture industry is one of the largest agricultural industry groupings, they grossly underestimate the full value of lifestyle horticulture activities in Australia. As a result, the commodities and services associated with the lifestyle horticulture industry have been poorly recognised and undervalued by the wider agricultural sector. Governments at all levels, as well as the community at large, can be said to take the value and benefits from the lifestyle horticulture industry for granted. Greater discussion needs to take place between the government, industry and community to increase teaching, research and extension funding into the lifestyle horticulture industry that contributes so much to AustraliaRSQUOs livelihood, lifestyle and quality of life.

Wear damage is one of the biggest problems associated with continuous use on sports and recreational turfgrass fields. Wear tolerance of 8 bermudagrass (Cynodon spp.) genotypes including 6 ecotypes collected from regional Australia and two commercial cultivars were evaluated in the field. Green cover after wear treatment of ecotypes 394 and MED3 was over 50% higher than the lowest genotypes. The wear tolerant genotypes also had significantly higher acid detergent fibre content, cellulose, lignin and total cell wall content than wear susceptible genotypes. Optical and scanning electron microscopies were used to study stolon and leaf transverse sections and leaf surface characteristics, respectively. Transverse sections of stolons and leaves, suggested that the fibre area surrounding vascular bundles of the wear tolerant genotypes was about 50% higher than the wear susceptible ones. Scanning electron micrographs of the leaf surface suggested that the arrangement of epidermal cells formed a ridged pattern. The gaps between the ridges of wear tolerant genotypes were shorter than those of the wear susceptible genotypes. Collectively, these results suggested that the mechanism of wear tolerance was associated with high fibre content in stolons and leaves. In addition, we suggest that the wear tolerant genotypes have a denser ridge pattern of epidermal cells probably giving the leaves greater tensile strength.

This chapter focuses on the practical implications of physiological processes on seed crop location and management, and on seed germination and establishment. The tiller is the basic growth unit in grasses. Floral initiation signals the start of the reproductive phase. Flowering occurs when the flowers on the inflorescence finally emerge in clear view and pollen is dispersed during anthesis. The timing of flowering largely determines the date of harvest, as well as stresses that could affect the plant. Seed dormancy is the failure of an intact viable caryopsis, contained within any covering structures it may have, to complete germination when placed under favorable moisture, oxygen, and temperature conditions. Embryo growth is intrinsically associated with imbibition and dormancy. Knowledge of plant development and flowering behavior is reflected in the management of seed crops to maximize potential yields, and also can highlight important limiting factors in certain environments on the production of good quality seed.

Water use in both urban and rural communities has become an enormous environmental and social issue, and over 30% of domestic water consumption is applied outdoors. To use Australia's unique biodiversity to select turfgrasses that maintain quality with reduced inputs of water and nutrients, we have collected about 500 indigenous couch grass genotypes and have begun to characterise them using physiological and genomics tools. Here we report on experiments that aim to develop the methodologies for screening a large number of genotypes for water use efficiency. Eight Cynodon grasses were grown in 40-cm-long PVC tubes with two soil types, two cutting heights, and four replications. The plants were grown at field capacity for several weeks prior to applying a terminal water stress. A survival period was estimated based on the time from the last watering to the time that all green leaf was lost. Large genotypic differences in survival period of up to 14 days were observed. Two genotypes, '81-1' and 'CT2', outperformed the other genotypes for survival period, possibly due to lower rates of evapotranspiration either through lower stomatal conductance and/or lower leaf area.

Traction is recognised as an important component of the overall playability and safety of a sportsfield. It relates to the "grip", or footing, provided through an athlete's shoe when in contact with the surface, and is normally measured by the torque generated when a weighted studded disc apparatus is dropped onto the turf and twisted manually. This paper describes the development of an automated traction tester, which mechanises the dropping and twisting of the weighted studded disc. By standardising these operational stages, more repeatable and reliable results can be expected than from the original hand-operated design where positioning of the disc and speed of rotation are controlled manually and so can vary from one measurement to the next. As well as measuring the maximum torque reached during rotation of the studded disc, the automated traction tester generates a profile of torque showing changes over time and calculates the angle through which the studded disc moved before reaching maximum torque. These aspects are now covered by a utility patent (PAT/AU/2004270767). Use of the automated traction tester is illustrated by comparative data for a range of warm-season turfgrasses, by comparisons of traction under different surface conditions generated by wear on Cynodon dactylon cultivars, and by the effects of environment, management and playing patterns on traction across a multi-use sports stadium.

Available evidence suggests that there are at least two locations for dormancy mechanisms in primary dormant seeds: mechanisms based within the embryo covering structures, and mechanisms based within the embryo. Mechanisms within the covering structures may involve mechanical, permeability and chemical barriers to germination. Mechanisms within the embryo may involve the expression of certain genes, levels of certain plant growth regulators, the activity of important respiratory pathways or the mobilisation and utilisation of food reserves. In addition, some embryos may be too immature to germinate immediately and must undergo a further growth phase before germination is possible. An individual species could have one or several of these various dormancy mechanisms and these mechanisms need to be understood when selecting treatments to overcome dormancy. The way in which certain dormancy breaking agents are thought to work is discussed and practical applications of such agents in field situations are explained.