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The potato cyst nematode, Globodera rostochiensis, is a quarantine pest in Australia affecting a relatively small number of properties in three different production areas in the State of Victoria. The effects of susceptible (Trent, Sebago and Coliban) and H1‐resistant potato cultivars (Atlantic, Crop 13 and Nicola) on nematode populations were compared in two trials in a naturally infested field in the 2008/09 season (Trial 1) and in the 2009/10 season (Trial 2). The latter included a bare fallow treatment. The reproduction factor Pf/Pi (final compared with initial nematode population) was used to determine treatment effects. Initial population density was very high, averaging 111 and 119 eggs g−1 soil in Trial 1 and 2, respectively. The Pf/Pi of population density (eggs g−1 soil) was greater after growing susceptible cultivars (average 1.74 and 2.92 in Trials 1 and 2, respectively) than after growing resistant cultivars (average 0.72 and 0.61 in Trials 1 and 2, respectively), or after a bare fallow (1.09) in Trial 2. This correlated with higher Pf/Pi values of cysts 500 g−1 soil and eggs cyst−1 for susceptible cultivars than for resistant cultivars. Average Pf/Pi values greater than one in both trials are consistent with more cysts and an increased population density after growing susceptible cultivars. There was a trend of population decline, that is, Pf/Pi < 1, after growing resistant cultivars (average Pf/Pi values of eggs cyst−1 of 0.77 and 0.35 and of eggs g−1 soil of 0.72 and 0.61, for Trials 1 and 2, respectively). However, Trial 2 showed that these Pf/Pi values were not significantly less than those for the bare fallow (0.68 eggs cyst−1 and 1.09 eggs g−1 soil). The susceptible cultivars Trent and Sebago produced lower yields than the resistant cultivars in both trials. In contrast, the susceptible Coliban yielded as well as the resistant cultivars, suggesting a high level of tolerance of this cultivar to infestation by the nematode. The resistant cultivar Crop 13 produced 34% and 36% greater total yields in Trials 1 and 2, respectively, than the once popular, but susceptible cultivar Sebago. This is the first report of the effects of potato cultivars on a population of the potato cyst nematode in an Australian field. The use of H1‐resistant potato cultivars can feasibly reduce populations of G. rostochiensis Ro1 on infested land and reduce PCN risk on land regulated as "linked" with infested land. [ABSTRACT FROM AUTHOR]

The western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), is an important pest of fresh horticultural produce and as such is considered a biosecurity risk in many countries from which it is absent. Information is needed on the radiation tolerance of important surface pests of quarantine importance such as F. occidentalis so that phytosanitary irradiation treatments for exported fresh commodities can be lowered to below the 400 Gy generic treatment currently approved for most insects in the United States and Australia. Lowering the dose will help minimize any product quality problems, reduce costs, and shorten treatment time. In large-scale confirmatory trials conducted in two independent laboratories in Hawaii and Australia, a dose of 250 Gy (measured doses 222–279 Gy) applied to adult F. occidentalis on green beans resulted in no reproduction in 5,050 treated individuals. At 250 Gy, the effective dose is significantly below the 400 Gy generic dose, demonstrating that irradiation at this lowered level is an effective method for the disinfestation of F. occidentalis from fresh horticultural produce. [ABSTRACT FROM AUTHOR]

Abstract: Light brown apple moth Epiphyas postvittana is a significant horticultural pest native to Australia that currently has a limited global distribution. However, this pest can tolerate very heterogeneous climates and has a wide host range. It has recently established in California with considerable consequences for US international and domestic trade. It has resulted in increasing calls for targeted risk assessment so that appropriate quarantine measures can be put in place to prevent its entry into new regions and further spread. Potential global distribution has been predicted by comparing the climatic conditions of its native (Australia) and long-established (New Zealand) ranges to the rest of the world using CLIMEX. It was suggested that E. postvittana has potential to establish mainly in countries in Central and South America, southern Africa, Western Europe and Southeast Asia. The study provides basic information for further assessment of the establishment capacity of this species in new habitats, and adds to the knowledge required to make science-based decisions in biosecurity. [Copyright &y& Elsevier]

Adult bean thrips, Caliothrips fasciatus (Pergande), overwintering inside the navel of navel oranges shipped from California to Australia, are an actionable pest for the importing country, i.e. infested lots are fumigated with methyl bromide. Strict quarantine regulations regarding C. fasciatus prompted studies on the best colour sticky trap that might be used to monitor for bean thrips populations in the vicinity of California citrus groves prior to harvesting fruit for export. Preliminary experiments identified the most attractive trap of each of four colours (blue, green, white, yellow) commonly used to sample adult Thysanoptera. Three trials of a field study were conducted, comparing C. fasciatus capture on the best card of each colour using asparagus ferns naturally infested with high levels of this pest. Based on significantly higher catch on green sticky cards, this colour trap is recommended for potential use in California's bean thrips mitigation plan designed to reduce thrips levels on citrus exported to Australia. [ABSTRACT FROM AUTHOR]