A Review of Transport Practices and Mortalities in pigs in Australia

The closure of abattoirs in Australia dictates that pigs will be transported over greater distances resulting in increased costs and reduced margins for producers. Factors contributing to reduced margins could include increased freight costs, reduced scale weight as a result of reduced killing out percentage and condemnations (due to injuries) plus possible increased deaths in transport. More information is needed in Australia on transport practices and mortalities to address knowledge deficiencies in our understanding of the welfare implications of road transport

Contributions of soil and crop factors to plant available soil water capacity of annual crops on Black and Grey Vertosols

Improved methods for field measurements of plant available soil water capacity (PAWC) of Black and Grey Vertosols in Australia’s north-eastern grain region were employed to characterise 83 soil–crop combinations over 7 depth intervals to 180 cm. Soil sub-order was shown to influence all components of PAWC (means of 224 and 182 mm in Black and Grey Vertosols, respectively) with drained upper limit (DUL), bulk density (BD), and crop lower limits (CLL) showing clear separation between soil sub-orders and a trend with soil depth. In addition to soil sub-order and soil depth effects, CLL showed crop effects such that expected PAWC of various crops when adjusted for soil sub-orders were: cotton 240 mm; wheat 233 mm; sorghum 225 mm; fababean 209 mm; chickpea 197 mm; barley 191 mm; and mungbean 130 mm. A total of 549 measured CLL values were used to develop a predictive model for estimating CLL from the soil sub-order, depth, DUL, and crop by predicting a CLL as a function of DUL and a depth-dependent variable for each crop–soil sub-order. The model CLL = DUL * (a + b * DUL) explained 85% of observed variation in the measured data with no significant bias between observed and predicted data. While properly measured data would be more reliable than estimated data, where specific site accuracy is less critical, this model may be used to estimate PAWC with an acceptable degree of accuracy

Spatial and Electronic Manipulation of Silicon Nanocrystals by Atomic Force Microscopy

[As silicon-based devices shnnk, interest is increasing in fast, low-power devices sensitive to small numbers of electrons. Recent work suggests that MOS structures with large arrays of Si nanocrystals comprising a floating gate can be extremely fast, reliable and nonvolatile relative to conventional floating gate memories. In these structures approximately one electron is stored per nanocrystal. Despite promising initial results, current devices have a distribution of charge transit times during writing of nanocrystal ensembles, which limits speed. This behavior is not completely understood, but could be related to a dispersion in oxide thicknesses, nanocrystals interface states, or shifts in the electronic bound states due to size variations. To address these limitations, we have developed an aerosol vapor synthesis/deposition technique for silicon nanocrystals with active size classification, enabling narrow distributions of nanocrystal size (~10-15% of particle in the 2-10 nm size range). The first goal of these experiments has been to use scanning probe techniques to perform particle manipulation and to characterize particle electronic properties and charging on a single-particle basis. Si nanocrystal structures (lines, arrows and other objects) have been formed by contact-mode operation and subsequently imaged in noncontact mode without additional particle motion. Further, single nanocrystal charging by a conducting AFM tip has been observed, detected as an apparent height change due to electrostatic force, followed by a slow relaxation as the stored charge dissipates. Ongoing and future efforts will also be briefly discussed, including narrowing of nanocrystal size distributions, control of oxide thickness on the nanocrystals, and measurements of electron transport through individual particles and ensembles

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

Are mungbean-compatible wild bradyrhizobia more resilient to abiotic stress?

Bradyrhizobia required by mungbean for nitrogen fixation can be impacted by abiotic stresses, reducing nitrogen fixation and yield. Wild bradyrhizobia were collected from ten sites in the dry tropics of Queensland and compared with the commercial strain for performance of inoculated mungbeans, under neutral and acid soil conditions. We found thirteen of the fifteen strains tested promoted growth at least as well as the commercial strain under both acid and neutral conditions. Two significantly outperformed the commercial strain under neutral conditions. This study suggests that gains could be made in mungbean performance through use of better-adapted bradyrhizobia

The longevity of para-aminopropiophenone (PAPP) wild dog baits and the implications for effective and safe baiting campaigns

Considerable effort goes into mitigating the impacts caused by invasive animals and prohibiting their establishment or expansion. In Australia, management of wild dogs (Canis lupus dingo and their hybrids) and their devastating impacts is reliant upon poison baiting. The recent release of baits containing the humane toxin para-aminopropiophenone (PAPP) offers potential improvements for control of wild dogs, but little is known about the environmental persistence of PAPP in manufactured baits that could be used to inform best practice guidelines. We investigated the degradation rate of PAPP wild dog baits (DOGABAIT™) under typical field usage and storage conditions in north-eastern Australia and calculated optimal deployment and withholding periods. The PAPP content of buried baits declines faster than surface-laid baits, but both presentations retained lethal doses to wild and domestic dogs for considerable periods (6–16 weeks). Domestic or working dogs should be suitably restrained or excluded from baited areas for extended periods, particularly under dry conditions, to minimise poisoning risk. The period of persistence of PAPP baits may provide opportunities to improve the duration or longer term efficacy of baiting campaigns, but care is needed to protect domestic and working dogs to ensure responsible and safe use

Imazapic and diuron availability and toxicity in different soils

Take home message • Herbicide residue levels can be measured in soil, but to interpret what soil analysis results mean for the subsequent crop, information about crop toxicity thresholds, and soil-specific herbicide availability is needed. • An approach has been developed to derive toxicity thresholds and predict herbicide availability in different soils to provide a prediction of safety for cropping. • Soil analysis for herbicide residues is not a replacement for using herbicides according to label requirements. • Additional ground truthing of this proof-of-concept research across a wider range of soil types and environments will strengthen the predictions

Cereal and Pulse Crops with Improved Resistance to Pratylenchus thornei Are Needed to Maximize Wheat Production and Expand Crop Sequence Options

n the subtropical grain region of eastern Australia, two experiments were conducted, one initially with 2490 P. thornei/kg soil, the other with 8150 P. thornei/kg soil at 0–0.9 m soil depth. We determined the effect of P. thornei, residual from a weed-free fallow and pre-cropping with several cultivars each of barley (Hordeum vulgare), faba bean (Vicia faba), chickpea (Cicer arietinum), and wheat (Triticum aestivum) (Phase 1), on the growth of wheat cultivars with intolerance or tolerance to P. thornei (Phase 2). Pratylenchus thornei substantially increased after growing all cultivars of the Phase 1 faba bean, barley, and most cultivars of chickpea and wheat, and decreased after two moderately resistant wheat cultivars and the fallow treatment. The biomass of the Phase 2 tolerant cultivar ranged from 5070 to 6780 kg/ha and the intolerant cultivar 1020 to 4740 kg/ha. There was a negative linear relationship between P. thornei population densities and biomass of the Phase 2 intolerant cultivar but not of the tolerant cultivar. Growers are at risk of financial loss because they are restricted in their choice of crops to reduce damaging population densities of P. thornei. The development of resistant and tolerant crop genotypes can maximize production in P. thornei-affected farming systems