Gaseous Nitrogen Losses Following Soil Amendment with Biosolids under Controlled Conditions.

This paper quantifies gaseous N losses due to ammonia volatilisation and denitrification under controlled conditions at 30 degrees C and 75% to 150% of Field Capacity (FC). Biosolids were mixed with two contrasting soils from subtropical Australia at a rate designed to meet crop N requirements for irrigated cotton or maize (i.e., equivalent to 180 kg N ha(-1)). In the first experiment, aerobically (AE) and anaerobically (AN) digested biosolids were mixed into a heavy Vertosol soil and then incubated for 105 days. Ammonia volatilization over 72 days accounted for less than 4% of the applied NH4-N but 24% (AN) to 29% (AE) of the total applied biosolids' N was lost through denitrification in 105 days. In the second experiment AN biosolids with and without added polyacrimide polymer were mixed with either a heavy Vertosol or a lighter Red Ferrosol and then incubated for 98 days. The N loss was higher from the Vertosol with 16-29% of total N applied versus the Red Ferrosol with 7-10% of total N applied, while addition of polymer to the biosolids increased N loss from 7 to 10% and from 16 to 29% in the Red Ferrosol and Vertosol, respectively. A major product from the denitrification process was N-2 gas, accounting for >90% of the emitted N gases from both experiments. Our findings demonstrate that denitrification could be a major pathway of gaseous N losses under warm and moist conditions.

Controlled pollination methods for creating Corymbia hybrids.

Inter-specific Corymbia hybrids are of increasing interest to plantation forestry, yet there is little knowledge of the most suitable controlled pollination methods for this genus. Inter-specific crosses were made between C. torelliana [CT(maternal parent)] and C. citriodora subsp. variegata (CCV), C. henryi (CH) and C. citriodora subsp. citriodora (CCC) using conventional pollination, one-stop pollination (OSP) and artificially-induced protogyny on yellow buds (AIP Y) pollination methods. Additional treatments included AIP on green buds (AIP G) and the use of exclusion bags for the OSP and AIP methods. Inter-specific hybrids (CT x CCV, CT x CH and CT x CCC) were successfully created using all three pollination methods. The AIP Y treatment provided the highest seed yields and achieved time savings of >41% over the conventional and OSP methods, resulting in up to five-fold increases in operator productivity. However, the AIP Y treatment also had the highest C. torelliana contamination levels (9.3–13.2%). The use of exclusion bags with the AIP method had minimal effect on contamination rates, indicating a high proportion of selfpollen contamination. Contamination rates varied between maternal parents, suggesting variation in selfcompatibility for C. torelliana individuals. AIP using semi-ripe green buds was not effective at reducing selfing and had low operator productivity. The AIP method is suitable for use in a large-scale hybrid breeding program for C. torelliana. When self-pollination effects are managed, it could greatly reduce the costs associated with the production of seed of elite family crosses for commercial forestry deployment.

Improving production of cows and fattening cattle in Indonesia and north Australia

To increase numbers and reproduction in Ongole and Bali cows by as much as 60% in Indonesia requires use of rice straw for maintenance of cows and higher quality feed and crop by-products for growth and fattening of calves. These feedstuffs exist in large quantities. The project will couple feeding systems with management (controlled mating with a selected bull, weaning, compost production), previously developed by the project team, in village-based adaptive research across the main cattle regions of Indonesia, with emphasis on East Java. The project will link with research on nutrition interactions with reproduction of cows in indigenous pastoral systems in north Australia.

Effects of climate change on reproduction,larval development, and adult health of coral trout (Plectropomus spp.)

Climate change is emerging as the single greatest threat to coral-reef ecosystems.The most immediate impacts will be a loss of diversity and changes to fish community composition and may lead to eventual declines in abundance and productivity of key fisheries species. A key component of this research is to assess effects of projected changes in environmental conditions (temperature and ocean acidity) due to climate change on reproduction, growth and development of coral trout (Plectropomus leopardis).Ultimately, this research will fill key knowledge gaps about climate change impacts on larger fishes, which are fundamental to optimizing resilience-based management, and in turn improve the adaptive capacity of industries and communities along the Great Barrier Reef.

Controlled exposure as a management tool for Glassers disease

Control of bacterial disease of pigs.

Porous silica-based nanocapsules for targeted and controlled release of biocides

Develops a new technology for the delivery of biocides against agricultural pests, with biocides contained within silica nanocapsules which are themselves protected by an outer envelope, capable of being selectively broken down by the target pest. Will reduce the amount of biocide escaping into the environment, prolong the life of the biocide, reduce biocide usage rates, and reduce undesirable effects on non-target organisms.

CRC30032 Enhancing surveillance with remotely controlled aircraft

Detecting spores with UAV.

Economic evaluation of precision controlled traffic farming in the Australian sugar industry: a case study of an early adopter

Controlled traffic has been identified as the most practical method of reducing compaction-related soil structural degradation in the Australian sugarcane industry. GPS auto-steer systems are required to maximize this potential. Unfortunately there is a perception that little economic gain will result from investing in this technology. Regardless, a number of growers have made the investment and are reaping substantial economic and lifestyle rewards. In this paper we assess the cost effectiveness of installing GPS guidance and using it to implement Precision Controlled Traffic Farming (PCTF) based on the experience of an early adopter. The Farm Economic Analysis Tool (FEAT) model was used with data provided by the grower to demonstrate the benefits of implementing PCTF. The results clearly show that a farming system based on PCTF and the minimum tillage improved farm gross margin by 11.8% and reduced fuel usage by 58%, compared to producers' traditional practice. PCTF and minimum tillage provide sugar producers with a tool to manage the price cost squeeze at a time of low sugar prices. These data provide producers with the evidence that investment in PCTF is economically prudent.

Reproduction of phosphine resistant Rhyzopertha dominica (F.) following sublethal exposure to phosphine.

Phosphine fumigation is commonly used to disinfest grain of insect pests. In fumigations which allow insect survival the question of whether sublethal exposure to phosphine affects reproduction is important for predicting population recovery and the spread of resistance. Two laboratory experiments addressed this question using strongly phosphine resistant lesser grain borer, Rhyzopertha dominica (F.). Offspring production was examined in individual females which had been allowed to mate before being fumigated for 48 h at 0.25 mg L -1. Surviving females produced offspring but at a reduced rate during a two-week period post fumigation compared to unfumigated controls. Cumulative fecundity of fumigated females from 4 weeks of oviposition post fumigation was 25% lower than the cumulative fecundity of unfumigated females. Mating potential post fumigation was examined when virgin adults (either or both sexes) were fumigated individually (48 h at 0.25 mg L -1) and the survivors were allowed to mate and reproduce in wheat. All mating combinations produced offspring but production in the first week post fumigation was significantly suppressed compared to the unfumigated controls. Offspring suppression was greatest when both sexes were exposed to phosphine followed by the pairing of fumigated females with unfumigated males and the least suppression was observed when males only were fumigated. Cumulative fecundity from 4 weeks oviposition post fumigation of fumigated females paired with fumigated males was 17% lower than the fecundity of unfumigated adult pairings. Both of these experiments confirmed that sublethal exposure to phosphine can reduce fecundity in R. dominica.

Reducing the risk of herbicide runoff in sugarcane farming through controlled traffic and early-banded application

The off-site transport of agricultural chemicals, such as herbicides, into freshwater and marine ecosystems is a world-wide concern. The adoption of farm management practices that minimise herbicide transport in rainfall-runoff is a priority for the Australian sugarcane industry, particularly in the coastal catchments draining into the World Heritage listed Great Barrier Reef (GBR) lagoon. In this study, residual herbicide runoff and infiltration were measured using a rainfall simulator in a replicated trial on a brown Chromosol with 90–100% cane trash blanket cover in the Mackay Whitsunday region, Queensland. Management treatments included conventional 1.5 m spaced sugarcane beds with a single row of sugarcane (CONV) and 2 m spaced, controlled traffic sugarcane beds with dual sugarcane rows (0.8 m apart) (2mCT). The aim was to simulate the first rainfall event after the application of the photosynthesis inhibiting (PSII) herbicides ametryn, atrazine, diuron and hexazinone, by broadcast (100% coverage, on bed and furrow) and banding (50–60% coverage, on bed only) methods. These events included heavy rainfall 1 day after herbicide application, considered a worst case scenario, or rainfall 21 days after application. The 2mCT rows had significantly (P < 0.05) less runoff (38%) and lower peak runoff rates (43%) than CONV rows for a rainfall average of 93 mm at 100 mm h−1 (1:20 yr Average Return Interval). Additionally, final infiltration rates were higher in 2mCT rows than CONV rows, with 72 and 52 mm h−1 respectively. This resulted in load reductions of 60, 55, 47, and 48% for ametryn, atrazine, diuron and hexazinone from 2mCT rows, respectively. Herbicide losses in runoff were also reduced by 32–42% when applications were banded rather than broadcast. When rainfall was experienced 1 day after application, a large percentage of herbicides were washed off the cane trash. However, by day 21, concentrations of herbicide residues on cane trash were lower and more resistant to washoff, resulting in lower losses in runoff. Consequently, ametryn and atrazine event mean concentrations in runoff were approximately 8 fold lower at day 21 compared with day 1, whilst diuron and hexazinone were only 1.6–1.9 fold lower, suggesting longer persistence of these chemicals. Runoff collected at the end of the paddock in natural rainfall events indicated consistent though smaller treatment differences to the rainfall simulation study. Overall, it was the combination of early application, banding and controlled traffic that was most effective in reducing herbicide losses in runoff. Crown copyright © 2012

Issues and solutions for researching weed eradication target species

Species biology drives the frequency, duration and extent of survey and control activities in weed eradication programs. Researching the key biological characters can be difficult when plants occur at limited locations and are controlled immediately by field crews who are dedicated to preventing reproduction. Within the National Four Tropical Weeds Eradication Program and the former National Siam Weed Eradication Program, key information needed by the eradication teams has been obtained through a combination of field, glasshouse and laboratory studies without jeopardising the eradication objective. Information gained on seed longevity, age to reproductive maturity, dispersal and control options has been used to direct survey and control activities. Planned and opportunistic data collections will continue to provide biological information to refine eradication activities.

Synthesis of Silica Vesicles with Controlled Entrance Size for High Loading, Sustained Release, and Cellular Delivery of Therapeutical Proteins

A rationally designed two-step synthesis of silica vesicles is developed with the formation of vesicular structure in the first step and fine control over the entrance size by tuning the temperature in the second step. The silica vesicles have a uniform size of ≈50 nm with excellent cellular uptake performance. When the entrance size is equal to the wall thickness, silica vesicles after hydrophobic modification show the highest loading amount (563 mg/g) towards Ribonuclease A with a sustained release behavior. Consequently, the silica vesicles are excellent nano-carriers for cellular delivery applications of therapeutical biomolecules.

Controlled release of ethylene gas from the ethylene-α-cyclodextrin inclusion complex powder with deliquescent salts

Deliquescent calcium chloride (CaCl2) and magnesium chloride (MgCl2) were investigated for their practical application to release ethylene gas from an ethylene-α-cyclodextrin inclusion complexes (CD IC) powder at relative humidities (RHs) between 11.2 and 93.6 % at 18 °C. The IC powder and deliquescent salts were mixed at a ratio of 1:5, respectively. CaCl2 and MgCl2 started to deliquesce at 32.7 % RH. The IC powder dissolved in the concentrated salt solutions to release ethylene gas. Increasing the RH accelerated the release rate. Maximum release of ethylene gas was achieved after 24 h at 75.5 and 93.6 % RH for both IC powder-deliquescent salts mixture. The deliquescent salts proved to be a simple option for releasing ethylene gas from the IC powder.

The growth, reproduction and survival of 'Cascabela thevetia' seedlings under two levels of canopy cover

The ornamental tree 'Cascabela thevetia', from tropical America, has naturalised and formed large infestations at several locations in northern Australia. Some understanding of its ecology and invasiveness was gleaned from a field experiment undertaken in North Queensland. The experiment quantified the growth, time to seed formation and survival of seedlings of the peach biotype growing under light and dense canopy cover within a riparian habitat. Growth, reproduction and survival of young plants varied. Growth was most rapid for seedlings away from, or on the edge of infestations because they were constrained by parent plants. The findings also suggested that land managers have at least 12 months following control to detect new plants, or regrowth, before plants set seed and replenish soil seed banks.