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The Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) is one of the most economically important pest insects of fruit crops worldwide. Mediterranean fruit fly can cause up to 100% crop loss in susceptible fruit. In order to formulate best management practices, it is critical to understand how Mediterranean fruit fly overwinters in a given geographical location and bridge the gap between autumn and spring populations. In this study, we evaluated the overwintering potential of Mediterranean fruit fly immature and adult stages in two locations in Perth Hills, Western Australia. We also monitored wild adult Mediterranean fruit fly populations for 2 yr. Adults were present year-round with captures very low in winter to early spring relative to summer and autumn. Field experiments revealed that immature stages in apples (eggs/first instar) and soil (pupae) remained viable in winter, emerging as adults at the onset of warmer weather in spring. In field cages, adults survived 72-110 d, and female laid viable eggs when offered citrus fruit, though only 1-6% eggs survived to emerge as adults. Adults survived longer in field cages when offered live citrus branch. The findings suggest that all Mediterranean fruit fly life stages can survive through mild winter, and surviving adults, eggs in the fruit and/or pupae in the soil are the sources of new population that affect the deciduous fruit crops in Perth. We recommend that Mediterranean fruit fly monitoring is required year-round and control strategies be deployed in spring. Furthermore, we recommend removal of fallen fruit particularly apple and other winter fruit such as citrus., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The use of dwarfing genes has resulted in the most significant improvements in yield and adaptation in cereal crops. The allelic dwarfing gene sdw1/denso has been used throughout the world to develop commercial barley varieties. The sdw1 gene has never been used successfully for malting barley, but only for a large number of feed varieties. One of the gibberellin 20-oxidase genes (Hv20ox₂) was identified as the candidate gene for sdw1/denso. Semi-quantitative real-time RT-PCR revealed that Hv20ox₂ was expressed at different levels in various organs of barley. Transcriptional levels were reduced in leaf blade, sheath, stem and rachis tissue in the barley variety Baudin with the denso gene. Subsequently, the relative expression levels of Hv20ox₂ were determined by quantitative real-time RT-PCR in a doubled haploid population and mapped as a quantitative trait. A single expression quantitative trait locus (eQTL) was identified and mapped to its structural gene region on chromosome 3H. The eQTL was co-located with QTLs for yield, height, development score, hectolitre weight and grain plumpness. The expression level of Hv20ox₂ was reduced fourfold in the denso mutant, but around 60-fold in the sdw1 mutant, compared to the control variety. The reduced expression level of Hv20ox₂ enhanced grain yield by increasing the number of effective tillers, but had negative effects on grain and malting quality. The sdw1 gene can be used only in feed barley due to its severe reduction of Hv20ox₂ expression. The gene expression marker for Hv20ox₂ can be used to distinguish different alleles of sdw1/denso.

Field trials were conducted in Western Australia to compare captures of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), in a standard male-targeted trap (Lynfield trap baited with Capilure) with a synthetic, female-targeted attractant marketed as BioLure. BioLure was also compared with other fenale attractants (orange ammonia, liquid protein bait) and tested in plastic McPhail, Tephri, and Lynfield traps. The possibility of using one trap to monitor female and male C. capitata populations was also tested by combining BioLure in a trap with the male attractant, Capilure. The results of these experiments show that BioLure outperformed the female-targeted system currently used for monitoring female C. capitala (liquid protein in MePhail trap). More male C. capitata were caught in the standard male-targeted trap, but more females were caught in traps baited with BioLure irrespective of trap type, climate, host tree, or population level. Combined lure traps caught equivalent total numbers of C. capitata to the standard male-targeted trap, but fewer females were captured. Tephri traps caught more flies than McPhail traps, but McPhail traps caught equivalent proportions of females. We compared the performance in commercial orchards of the standard male-targeted trap with a female-targeted trap (McPhail with BioLure). We found that the male trap detected C. capitata more often, caught more flies, triggered the economic threshold more often (66% of the time) and was more cost effective. The male-targeted trap is recommended for use on commercial orchards if cost is limiting. However, using both male and female-targeted traps increases the chance of detecting flies and triggering the economic threshold level. The synthetic female attractant is recommended for replacement of protein hydrolysate lures and may be used in either Tephri or McPhail traps.