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Females of the Queensland fruit fly (QFF), Bactrocera tryoni, are amongst the most damaging pests of horticulture in Australia and neighboring countries. Females can lay eggs into more than a hundred species of fruits and vegetables, resulting in large crop losses. Sexually mature males can be managed sustainably with traps baited with long-lasting synthetic lures, and sexually immature males and females can be attracted and killed by short-lived protein baits applied directly on surfaces, with a low success rate (< 20%). No long-lasting attractants for virgin or mated females exist. With the aim of developing a female attractant for surveillance, we collected and analyzed the odors of four ripe host fruits: orange, cherry guava, banana and feijoa. Virgin and mated female QFF were tested with gas-chromatography coupled with electro-antennographic detection to identify electrophysiologically (EAD)-active compounds. We detected 41 EAD-active compounds, with seven found common for more than one fruit. Overall, mated females responded more often and with higher intensity than virgin females. In particular, five compounds present either in cherry guava or feijoa triggered a significantly higher EAD response from mated females than from virgins. Twenty-six EAD-active compounds were selected and tested individually in a Y-tube olfactometer to measure attraction of both virgin and mated females. Behavioral responses differed significantly amongst the compounds, but not strongly between virgin and mated females. We did not find any correlation between electrophysiological and behavioral responses. Further field testing with behaviorally-active compounds is needed for the development of a new QFF female lure. [ABSTRACT FROM AUTHOR]

Fiji leaf gall has been a major disease in the Australian sugarcane industry, causing extensive crop losses in the 1970–1990 period. The disease has been managed via a number of measures including varietal resistance, disease-free plant sources, termination of heavily-infested crops, quarantine and rogueing of disease stools. These measures have been highly effective and reduced detected disease incidence to zero in several districts. Over 32,000 crop inspections have been undertaken since the last known diseased crop was sighted in the Central Queensland region. All disease inspection data were collated and analysed for this region, with modelling undertaken to determine the probability of the disease being present but remaining undetected. These analyses suggest that it is very highly unlikely to be present; a proposal is made therefore to declare 'area freedom from Fiji leaf gall' for the Central Queensland region. •. FLG has caused extensive crop and financial losses within the Australian industry. •. It is over 25 years since the disease has been detected in Central Queensland. •. Over 32,000 crop inspections failed to detect the disease. •. Probability modelling suggests FLG is extremely unlikely to be present in CQ. •. We suggest 'area freedom' be declared for Central Queensland. [ABSTRACT FROM AUTHOR]

In Queensland, Australia, strawberry (Fragaria × ananassa Duchesne) is grown in open fields and rainfall events can damage fruit. Following a rain event, damage was evaluated on three commercial cultivars. ‘Rubygem’ (80%) had more fruit damaged than ‘Strawberry Festival’ (55%) and ‘Camarosa’ (61%). “Etch,” where the surface of the fruit is eroded and, consequently, the seeds are raised relative to the damaged surface, was the most frequently occurring (>80%) damage type and was distributed on the body and tip of the fruit, while some fruit (<16%) showed cracking. Fully mature fruit was damaged (>80%) more than partially mature fruit, which differed between ‘Strawberry Festival’ (16%) and ‘Rubygem’ (68%). Cultivars that are resistant to rain damage would reduce losses and lower risk for the growers. [ABSTRACT FROM AUTHOR]