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Up to 32 Colletotrichum species have been reported to be associated with pre‐ or postharvest diseases of citrus globally, while in Australia, six species have been reported to cause citrus leaf and fruit disease. Twig or shoot dieback has recently been observed as an emerging disease in citrus orchards in Western Australia. Colletotrichum species were isolated from diseased twigs showing dieback (withertip) or lesions, with or without gummosis, collected from 12 varieties of orange, mandarin and lemon. Colletotrichum gloeosporioides sensu stricto, Colletotrichum karstii and Colletotrichum novae‐zelandiae were identified using a polyphasic approach that included multigene phylogenetic analysis using sequences of internal transcribed spacer and intervening 5.8S nrDNA (ITS), glyceraldehyde‐3‐phosphate dehydrogenase (gapdh), β‐tubulin (tub2), actin (act) and histone (his3) for isolates in the boninense species complex, and Apn2–Mat1–2 intergenic spacer and partial mating type (Mat1–2) (ApMat) and glutamine synthetase (gs) for isolates in the gloeosporioides species complex, as well as morphological characteristics. C. gloeosporioides was the most prevalent species associated with twig dieback in Western Australia, while C. novae‐zelandiae was reported for the first time in Australia. Pathogenicity tests on shoot twigs from lemon and orange trees confirmed C. gloeosporioides, C. karstii and C. novae‐zelandiae as the cause of twig dieback, with C. gloeosporioides being the most aggressive species. Knowledge of the species causing twig dieback and their lifestyle will assist the development of integrated control methods. [ABSTRACT FROM AUTHOR]

This study reports the performance of seven Valencia (Citrus sinensis) selections grafted to four Trifoliata (Poncirus trifoliata) rootstocks in the Riverina region of south-east Australia. Six of the Valencia selections (numbered as Valencia 1 to 6) were from orchards in the Riverina region, and the seventh was a standard commercial variety 'Keenan' (control). Three of the four Trifoliata rootstock selections ('Zao Yang', 'Tanghe', and 'Donghai') were imported from the People's Republic of China, and the fourth was the 'Tri22' (control) selection used commercially in Australia. 'Valencia 5' produced the highest cumulative (162 kg/tree) yield over the five harvest seasons and increased levels of Total Soluble Solids (TSS, 1.7 °Brix) compared with the current industry standard, 'Keenan'. Trees grafted to 'Zao Yang' produced higher yields than any of the other Trifoliata selections, again outperforming the current industry standard, 'Tri22'. The new combination of 'Valencia 5' scion on 'Zao Yang' rootstock represents an opportunity to significantly improve orchard productivity, particularly for juice production. 'Valencia 6' on Zao Yang' had the highest percentage (58%) of fruit >75 mm in diameter compared with other scion/rootstock combinations and creates an additional opportunity for fresh market production. Significant differences in tree size, growth rates, and productivity were identified. Results from this evaluation have resulted in the commercialisation of 'Valencia 5' and 'Valencia 6' scions and 'Zao Yang' rootstock as three new citrus varieties for sweet orange production in Australia. [ABSTRACT FROM AUTHOR]

The subcutaneous parasitic mite Hemimyialges macdonaldi was found in a specimen of the Orange‐bellied Parrot Neophema chrysogaster that died in captivity. A review of the host range and geographic distribution of this mite shows it is cosmopolitan and occurs in a very wide range of birds. It does not appear to be a cause of significant mortality in its hosts. [ABSTRACT FROM AUTHOR]

"Washington Navel" orange is the principal mid-season maturing cultivar grown in south-eastern Australia. The cultivar has strong export potential and earns high returns for citrus growers. However, trees bear a large number of small-sized fruit in an on-year followed by a small number of large-sized fruit the next year if crop load is not properly managed. Thinning can be used as a crop management strategy to adjust crop load. A thinning experiment was conducted, and crop loads were adjusted on a whole tree basis to 2, 4, 6 or 8 fruit/0.125 m3 canopy volume (CV), removing 46%, 30%, 20% and 8% of the crop respectively, and compared to non-thinned control trees. Fruit diameter was measured at regular intervals from February to July. Fruit yield and number were recorded for two consecutive seasons. Return bloom after thinning was also recorded. Thinning treatments 2, 4 and 6 fruit/0.125 m3 CV resulted in higher fruit growth rates of 24%, 9% and 14% compared to the control. Thinning to a crop load of 6 fruit/0.125 m3 CV produced the best results for fruit size and yield during the treatment year. The following year return bloom was increased in the 2, 4 and 6 fruit/0.125 m3 CV compared to the control. The 6 fruit/0.125 m3 CV treatment resulted in a higher cumulative yield of 169 kg/tree over two cropping seasons and 42% fruit in the size class > 75 mm diameter compared to the control. Economic analysis revealed that 6 fruit/0.125 m3 CV could generate an extra $4,240/ha of income for citrus growers. It was concluded that a fruit load of 6 fruit/0.125 m3 CV was required to produce high yields and large fruit size over two cropping seasons. [ABSTRACT FROM AUTHOR]

The present study investigated whether temperate wrasses in a geographical location in the southern hemisphere break open crab prey on anvils. Here, tool‐use behaviour is reported in two temperate wrasses, the orange wrasse Pseudolabrus luculentus and the doubleheader Coris bulbifrons, at Lord Howe Island, Australia. In addition to the previous observations of this behaviour, these findings suggest that tool use is common and may be ubiquitous, in medium‐sized carnivorous wrasses that are undergoing an ontogenetic shift from soft‐bodied to hard‐shelled prey. [ABSTRACT FROM AUTHOR]

Purpose: Higher total fruit and vegetable (FV) intakes have been associated with lower perceived stress. The relationship between specific types of FV and perceived stress remains uncertain. The aims of this cross-sectional study were to explore the relationship between consumption of specific types of FV with perceived stress in a population-based cohort of men and women aged ≥ 25 years from the Australian Diabetes, Obesity and Lifestyle (AusDiab) Study. Methods: Dietary intake was assessed using a validated Food Frequency Questionnaire (n = 8,640). Perceived stress was evaluated using a validated Perceived Stress Questionnaire, with values ranging 0–1 (lowest to highest). High perceived stress cut-offs of ≥0.34 for men and ≥0.39 for women were obtained from the highest quartile of the perceived stress score for each sex. Multivariable-adjusted logistic regression was performed to investigate the associations. Results: The mean age of participants (50.1% females) was 47.8 (SD 15) years. Persons in the highest, versus lowest, quartiles of apples and pears, orange and other citrus, and banana intakes had a significantly lower odds (24–31%) of having high perceived stress. Similarly, persons with higher intakes of cruciferous, yellow/orange/red, and legume vegetables had significantly lower odds (25–27%) of having high perceived stress. Conclusion: In Australian adults, a higher consumption of apples and pears, oranges and other citrus, and bananas, as well as cruciferous, yellow/orange/red, and legume vegetables were associated with lower odds of having high perceived stress. The recommendations of "eating a rainbow" of colours may assist in preventing and/or reducing perceived stress. [ABSTRACT FROM AUTHOR]

The prevalence ofmental illness is a critical public health issue. In Australia, the prevalence of mental illness is similar across all settings, however, people living in rural and remote areas experience worse outcomes than their urban counterparts. Access to mental health services is critical, however, the notion of accessibility needs to be understood in the context of the uniqueness and variability of the rural experience. The Orange Declaration on Rural and Remote Mental Health recognized that rural areas face a series of interconnected challenges and called for place-specific responses and new funding models that reward collaboration and local partnerships. In this paper, we argue that recent mental health planning, policy and service development uses a narrow interpretation of the notion of accessibility that is out of step with current thinking on the heterogeneity of the rural experience. We use some examples of our own research and experience in rural Western Australia to argue that the current commissioning model is not aligned with the Orange Declaration, and remains largely metro-centric and reliant on a narrow conceptualization of service accessibility. We argue that what is needed is a dynamic, responsive, context-sensitive understanding of accessibility that is informed by the distinctiveness of rural adversity, and recognizes the heterogeneity and variability of the rural experience whilst acknowledging rural agency and social capital, and we suggest that applying a socio-ecological approach to the development of new commissioning models provides a way forward. [ABSTRACT FROM AUTHOR]

Dejan Stojanovic and Robert Heinsohn introduce the Critically Endangered orange-bellied parrot from Australia. [ABSTRACT FROM AUTHOR]

During standardised bird surveys in September 2021 in the West Kimberly, two independent observations of an orange pigment variety in a male Black-bellied Crimson Finch Neochmia phaeton phaeton were recorded. This is the first documented observation of a wild Black-bellied Crimson Finch with this coloration. [ABSTRACT FROM AUTHOR]

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]

Citrus growers in Australia need to be able to produce large fruit size for premium returns in domestic and overseas markets. Therefore, it is important to manipulate the tree canopy by hedging in a “heavy-flowering” year to decrease crop load and enhance fruit size the following year. A two-year study was conducted on the relationship of fruit size to different inflorescence types that developed on bearing branch units (BBU) that developed in the summer following mechanical hedging during flowering in spring compared with non-hedged branches. Spring hedging produced a “stronger” vegetative growth flush compared to the non-hedged branches: BBU developing on hedged branches produced more sprouts, flowers, leafy inflorescences and 3.6 to 5 mm larger fruit size than BBU from non-hedged branches. Moderate severity mechanical hedging in the spring of “on-flowering” years is recommended as a practical means to manage the existing crop load, enhance fruit size and alleviate alternate bearing for the following year. [ABSTRACT FROM AUTHOR]

Abstract: Apple, orange and pineapple juices were used to prepare thickened fluids from six Australian commercially available food thickeners that are based on guar gum, modified starch and xanthan gum. Using a strain-controlled rheometer, changes in shear stress with the rate of shear (1–100s−1) at 20°C were independent of the thickener or fruit juice. As the solids content of the fluids increased, so were the viscosity, density and extrapolated yield stress. The density, yield stress and viscosity of the thickened fluids were not significantly influenced (p >0.05) by fruit juice, but the type of thickener significantly (p <0.05) affected these properties. The Herschel–Bulkley model was found to be the most suitable in describing the rheological data of the thickeners in the fruit juices. The relevant parameters obtained for the recommended models can be used to obtain a known viscosity of the thickened fluids, match to fluids used in videofluoroscopy and obtain objective classification of the thickened fluids. Sample calculations are included. [Copyright &y& Elsevier]

New early- and late-maturing navel orange varieties have expanded the navel orange season for California's domestic and export fresh-fruit market. For 5 years, we evaluated the fruit-quality characteristics of purported late-season varieties imported from Australia to determine whether they have any advantages over Lane Late, the first late-season navel orange imported from Australia and grown in California. Of the six varieties evaluated, Autumn Gold, Barnfield, Chislet, Powell and Lane Late had late-maturing characteristics, but none of these varieties stood out as having the lates maturing fruit for all traits associated with maturity at all nine locations studied. For certain locations, sample dates and years, there were significant differences among the varieties for quality traits associated with maturity, such as solids-to-acid ratio, percentage acidity and puncture resistance, but these differences varied depending upon location. [ABSTRACT FROM AUTHOR]

Green mould (Penicillium digitatum) and sour rot (Geotrichum citri-aurantii) in early season, thin-skinned navel oranges (Citrus sinensis) are of serious concern to the Australian citrus export industry. The pathogen causing the disease sour rot is particularly problematic because the control method for the Australian domestic market is to use fungicides containing guazatine, a chemical that is restricted for important export markets. In this study, we have examined possible alternative treatments to combinations of the two pathogens including the use of non-restricted fungicides in combination with gibberellic acid (GA3), generally regarded as safe (GRAS) compounds, and/or elevated temperature. When inoculated fruit were dipped in solutions containing the fungicide imazalil alone and in combination with GA3, thiabendazole, or carbendazim, the infection rate was reduced. GRAS compounds, sodium carbonate, and mineral oil, were also effective in reducing infection rates when mixed with imazalil, as was sodium carbonate alone and when mixed with GA3. GA3 was not effective at the rate tested (50 mg litre-1). Elevated temperature in most instances did not reduce disease incidence in fruit, although in experiments with control levels of inoculation below 80%, temperature was a factor in some treatments. Further experiments are necessary to demonstrate the potential of alternative treatments to limit sour rot and mould development on export fruit. [ABSTRACT FROM AUTHOR]

Development of Epipyas postvittna (Walker) (Lepidoptera: Tortricidae), on leaves and fruit of 'Valencia', 'Washington navel', and 'Navelina' orange trees was studied under constant and fluctuating temperatures. E. postvittna was able to complete its life cycle feeding exclusively on leaves or fruit of orange trees. However, larval survival rate was very low (<20%) on orange tissues compared with that on noncitrus hosts. Among the four types of orange tissues, young orange leaves and fruit afforded larvae higher survival rates than mature orange leaves and fruit. Fruit (young or mature) produced heavier pupae than leaves (young or mature). Larvae developed more slowly on mature orange fruit than on other orange materials and more slowly on orange leaves than on leaves of most noncitrus hosts. Degree-day accumulations based on the fastest developmental rates obtained in this study suggested that E. postvittna is capable of completing 4.4-4.7 generations per year in orange orchards in the Riverina region of New South Wales, Australia. Implications of the results in the management of the insect in citrus are discussed. [ABSTRACT FROM AUTHOR]

Three large-scale mating disruption (MD) trials were conducted from 2001 to 2004 in an organic citrus orchard in inland southeastern Australia to evaluate the effectiveness of the MD dispenser Isomate LBAM Plus in controlling lightbrown apple moth, Epiphyas postvittana (Walker), in citrus. At the application rate of 364–728 dispensers per ha, the dispensers reduced pheromone trapping of E. postvittana to almost undetectable levels for ≈6 mo in the treated area. During this period, most sentinel females in the treated area failed to mate. Infestation by E. postvittana in the treated area was reduced by >50%. If distributed in citrus orchards in late winter (August), the dispensers can be expected to remain effective until next February in southeastern Australia, covering the period when most fruit scarring caused by its larvae occurs. [ABSTRACT FROM AUTHOR]