A flight study of the pasture soldier fly

Oil-bath trap records over a period of 4 years on the Northern Tablelands of Queensland, together with field collection records, showed that flights of the pasture soldier fly (Altermetoponia rubriceps (Macq.)) occurred each year in the period from April to June, with a peak in early to mid May

Flight studies of pasture webworms

Oil-bath trap records over a period of 4 years on the Northern Tablelands of Queensland together with numerous field collection records showed that flights of Oncopera brachyphylla Turn. occurred in the period from February to early April, with a peak close to the beginning of March, and that flights of Oncopera mitocera (Turn.) occurred in the period from early March to early May, with a peak close to the beginning of April

Adaptations of locusts and grasshoppers to the low and variable rainfall of Australia

In Australia, where approximately 80% of the land area is arid or semiarid, rainfall is the major factor limiting acridid populations. Rainfall is not only limiting in terms of quantity but also in being highly variable, both temporally and spatially. In this paper, the main adaptations seen in Australian Acrididae to overcome limiting rainfall are discussed with special reference to economically important species. In the arid to semiarid subtropics (lat 23–33°S) rainfall is slightly summer-dominant but extended dry periods can occur in any season. Chortoicetes terminifera, the main pest species, avoids dry periods through embryonic diapause or survives dry periods as quiescent eggs or adults. Migration is critical for survival as it allows locusts to locate areas of localized rainfall. Outbreaks are frequent and develop when enough rain falls to allow continuous breeding over three to four generations. In temperate areas of subcoastal southern Australia, summers are dry and most rain falls in winter or early spring. Austroicetes cruciata, a univoltine pest species, avoids the dry summers by having an embryonic diapause between summer and early winter. In the tropical north (lat 13–23°S), rainfall is strongly summer-dominant and Austracris guttulosa, another univoltine species, survives the dry winter as immature adults in reproductive diapause. Adults mature after feeding on the green vegetation present following early rains of the wet season. But the early rains are often localized and adults migrate until they encounter these localized areas of rain. Adults then mature and lay, but the survival of their offspring eggs and very young nymphs is assured only if there is further rain within 6 weeks. Outbreaks develop only when there are several years of regular rains both in outbreak areas and adjacent areas of the arid zone. Locusta migratoria does not have a stage that can survive extended dry periods. Consequently, it is mainly restricted to subcoastal areas of moderate rainfall. In the main outbreak areas of subtropical Queensland, populations often decline during the commonly dry winters but outbreaks develop when good rain falls in all seasons

Growth and yield of 3 hybrid papayas (Carica papaya L.) under mulched and bare ground conditions

At Yarwun (151.3˚E, 23.75˚S), Australia, papaya Hybrid 29 yielded twice as much fruit as Hybrid 11 and 30% more than Hybrid 13. The plots mulched with coarse grass hay yielded 50% more fruit than the plots with bare ground. The highest yielding treatment, Hybrid 29 + mulch, averaged the equivalent of 81 t/ha.year over the 16.5-month harvest period. The yields were achieved in spite of inadequate water supply due to drought and the loss of 877 plants from 1441 plant positions (4 plants per position) due to the 3 phytoplasma diseases; dieback, yellow crinkle and mosaic. Hybrid 29 produced higher yields than the other hybrids by flowering early on shorter plants with thicker stems and setting more fruit that commenced lower down on the stem. Hybrid 13 was intermediate in size and the amount of fruit setting between Hybrid 29 and Hybrid 11 but was the slowest to flower and set fruit. Hybrid 11 had the thinnest and tallest stems, flowered at an intermediate time between the other 2 hybrids and produced fewer flowers and fruit resulting in the lowest yield. Mulching increased stem height and thickness, promoted earlier flowering and increased fruit set, yield and average fruit weigh

Post-ratoon growth and yield of three hybrid papayas (Carica papaya L.) under mulched and bare-ground conditions

At Yarwun (151.3°E, 23.75°S), a trial was conducted to compare 3 papaya hybrids (Hybrid 29, Hybrid 11 and Hybrid 13) under mulching with grass hay or in bare ground. The viability of ratooning a papaya crop was also investigated. After a 16-month cropping season plants were cut to a 750-mm stump (ratooned) about monthly over a 3.5-month period and, following a 4.5-month regrowth period, were harvested for a period of 11 months (post-ratoon). Hybrid 29 yielded (by weight) 54% more than Hybrid 11 and 92% more than Hybrid 13 during the 3.5-month ratooning period. At the commencement of ratooning, Hybrid 29 plants were 41–58 cm shorter than Hybrid 11 and 13 plants, allowing the Hybrid 29 plants to be retained for longer before being ratooned. Hybrid 29 also returned to fruiting more quickly with a greater proportion of plants (97%) with fruit at the first post-ratoon harvest compared with Hybrid 11 (87%). Following regrowth (post-ratoon) the 3 hybrids produced similar yields. All 3 hybrids were equally susceptible to the 3 phytoplasma diseases and to nematodes. The plots mulched with coarse grass hay yielded 70% more during the ratooning period and 116% more post-ratoon than the plots with bare ground. This difference was attributed in part to fewer root-knot nematodes, the roots being more heavily infected with vesicular arbuscular mycorrhiza, the use of the complete upper soil profile by the roots, reduced rainfall run off and less soil loss in the mulched treatment. The highest yielding treatment, mulched Hybrid 29, averaged the equivalent of 55 t/ha.year during ratooning, 43 t/ha.year over the 11-month post-ratoon harvest period and 65 t/ha.year over the entire plant–ratoon cycle. These yields were achieved in spite of drought conditions and quite severe outbreaks of the phytoplasma diseases, dieback, yellow crinkle and mosaic, with 60% of plant positions infected with dieback during the post-ratoon period. Theoretical yield estimations using the data from the plant and post-ratoon crops indicated that ratooning may give superior average monthly yields compared with 2 successive plant crops because of the reduced time required for the ratooned crop to return to production. The study demonstrated the benefits of mulching, the superiority of Hybrid 29 and that ratooning may be successfully used in papaya. In environments similar to Yarwun, Hybrid 29, or similar hybrids, with mulching is recommended for commercial production. If land, time or finances are limiting, consideration should be given to ratooning the plant crop based on monthly cut outs over a 3–4-month ratooning period with vacant plant positions replanted during ratooning

Growth, yield and phenology of 2 hybrid papayas (Carica papaya L.) as influenced by method of water application

Highly variable, outcrossed papaya lines irrigated with overhead sprinklers were grown at Yarwun (151.3˚E, 23.75˚S) in Queensland, Australia. The inherent variability made scientifically based comparative studies impractical. The advent of uniform hybrid papaya lines allowed the testing of 2 of these hybrids under 3 irrigation methods, 2 of which had the potential to greatly reduce water use compared with overhead sprinklers. Yields of 92 t/ha.year were achieved by both papaya Hybrids 29 and 1E. Water application method did not influence yield. About 26% of plants were lost due to the phytoplasma diseases dieback, yellow crinkle and mosaic over the life of the trial. Downward yield fluctuations were related to poor fruit set in winter when pollinators (Family Sphingidae) were not present and growth was slow due to hot dry periods affecting fruit set. The resultant fruit (about 6 months later) were small and reduced in number. Irrigation with overhead sprinklers using saline water (1400–4000 S/cm) damaged leaves and reduced growth of plants. Winter spot was most severe in July, August and September, in Hybrid 29 with overhead irrigation. Height of plants 13 weeks after planting was greater under trickle irrigation due to less damage from the saline water supply than in the overhead sprinkler treatment. Hybrid 29 set fruit at 94.3 cm above ground compared with 117.6 cm for Hybrid 1E

International survey on high- and low-dose synacthen test and assessment of accuracy in preparing low-dose synacthen

OBJECTIVE: The short synacthen test (SST) is widely used to assess patients for adrenal insufficiency but the frequency and protocols used across different centres for the low-dose test (LDT) are unknown. This study aimed to survey centres and test the accuracy of ten different synacthen preparation strategies used for the LDT. METHODS: Members of six international endocrine societies were surveyed regarding diagnostic tests used for adrenal insufficiency, and in particular the SST. Synacthen was diluted for the LDT and concentrations measured using a synacthen ELISA. RESULTS: Survey responses were received from 766 individuals across 60 countries (52% adult, 45% paediatric endocrinologists). The SST is used by 98% of centres: 92% using high-dose (250 μg), 43% low-dose, and 37% both. Ten low-dose dilution methods were assessed and variation in synacthen concentration was demonstrated with intra-method coefficients of variation (CV) ranging from 2.1% to 109%. The method using 5% dextrose as a diluent was the least variable (CV of 2.1%). The variation in dilution methods means that the dose of synacthen administered in a LDT may vary between 0.16 μg and 0.81 μg. CONCLUSIONS: The high-dose SST is the most popular diagnostic test of adrenal insufficiency but up to 72% of paediatric endocrinologists use a LDT. There is considerable variation observed both within and between low-dose synacthen dilution methods creating considerable risk of inaccurate dosing and thereby invalid results

Multivariable model to predict an ACTH stimulation test to diagnose adrenal insufficiency using previous test results

Context The adrenocorticotropin hormone stimulation test (AST) is used to diagnose adrenal insufficiency, and is often repeated in patients when monitoring recovery of the hypothalamo–pituitary–adrenal axis. Objective To develop and validate a prediction model that uses previous AST results with new baseline cortisol to predict the result of a new AST. Methods This was a retrospective, longitudinal cohort study in patients who had undergone at least 2 ASTs, using polynomial regression with backwards variable selection, at a Tertiary UK adult endocrinology center. Model was developed from 258 paired ASTs over 5 years in 175 adults (mean age 52.4 years, SD 16.4), then validated on data from 111 patients over 1 year (51.8, 17.5) from the same center, data collected after model development. Candidate prediction variables included previous test baseline adrenocorticotropin hormone (ACTH), previous test baseline and 30-minute cortisol, days between tests, and new baseline ACTH and cortisol used with calculated cortisol/ACTH ratios to assess 8 candidate predictors. The main outcome measure was a new test cortisol measured 30 minutes after Synacthen administration. Results Using 258 sequential ASTs from 175 patients for model development and 111 patient tests for model validation, previous baseline cortisol, previous 30-minute cortisol and new baseline cortisol were superior at predicting new 30-minute cortisol (R2 = 0.71 [0.49-0.93], area under the curve [AUC] = 0.97 [0.94-1.0]) than new baseline cortisol alone (R2 = 0.53 [0.22-0.84], AUC = 0.88 [0.81-0.95]). Conclusion Results of a previous AST can be objectively combined with new early-morning cortisol to predict the results of a new AST better than new early-morning cortisol alone. An online calculator is available at https://endocrinology.shinyapps.io/sheffield_sst_calculator/ for external validation