Tissue culture and subsequent field evaluation of strawberry

Strawberry plants of cv. Redlands Crimson, free of strawberry mild yellow edge virus (MYEV), have been produced by apical tip culture on a modified Adams (1972) medium. Explants from six other cultivars were grown on this medium and considerable variation in growth response was observed. No shoot growth was obtained on this medium with explants of cv. Phenomenal, however, growth was initiated on a modified Lee and De Fossard (1975) medium. Low media pH (4.2) inhibited shoot growth. Yield of six clones of cv. Redlands Crimson, free of MYEV and one virus infected clone were monitored for a fruiting season. Removal of MYEV had no effect on fruit quality, but uninfected clones had a 13% yield advantage of marketable fruit over the whole season. This increase was shown to occur during the two fruiting flushes and was a result of more vigorous plants having the capacity to produce more fruit. Commercial plantings of clones free of MYEV over five seasons have been characterised by high early yields

Phosphorus fertilizer for nitrogen fertilized dairy pastures. 1. Long term effects on pasture, diet and soil

The phosphorus fertilizer requirements and long term productivity of nitrogen-fertilized Gatton panic (Panicum maximum cv. Gatton) pastures, grazed by lactating dairy cows, were evaluated over 7 years. Cows grazed at 2·6 cows/ha on pastures that received annually 100 or 300 kg N/ha at each of 0, 22·5 or 45 kg P/ha. Phosphorus treatments were applied as single superphosphate, balanced for calcium by applications of gypsum. The soil had an initial available soil phosphorus content of 40 mg/kg (bicarbonate extraction). At zero P fertilizer (0P), extractable soil P declined at the rate of 1·9 mg/kg each year; at 22·5P it was maintained close to the original level while at 45P it increased at 6·6 mg/kg each year. Increased P fertilizer caused significant (P<0·01) increases in plant P concentration from year 2 onwards. In years 6 and 7 there was significantly less green pasture and leaf on offer in 300N pastures at 0P than with 22·5P and 45P. There was no influence of rate of P fertilizer at 100N on pasture quantity on offer in any year. There were clear trends at 100N of decreasing total pasture and green dry matter (DM) on offer over the 7 years, but not at 300N. Cows at 300N consumed more leaf in the diet in autumn and winter than at 100N. Leaf was 55–60% of the diet in summer and autumn, but decreased to 21% (100N) and 37% (300N) in winter. Dead material in the diet was always higher at 100N. Pasture leaf percentage and leaf yield were the best individual predictors of leaf percentage in the diet. Diet P selected from pasture was reduced by the higher rate of N fertilizer in each season. Estimated P concentrations of the diet selected from pasture for summer, autumn and winter averaged 0·30, 0·38 and 0·28% DM for 100N and 0·19, 0·24 and 0·18% DM for 300N treatments, respectively. The response to P fertilizer was dependent on the rate of N fertilizer applied. The critical bicarbonate extractable soil P level for this soil type, below which pasture responses occurred, was 30 mg/kg at 300N. The critical level at 100N was not reached, but was <23 mg/kg P

Parallel run length encoding compression: Reducing I/O in dynamic environmental simulations

Dynamic simulations based on time-varying inputs are extremely I/O intensive. This is shown by industrial applications generating environmental projections based on seasonal-to-interannual climate forecasts that have a compute to data access ratio of O(n) leading to significant performance degradation. Exploitation of compression techniques such as run length encoding (RLE) significantly reduces the I/O bottleneck and storage requirements. Unfortunately, traditional RLE algorithms do not perform well in a parallel vector platform such as the Cray architecture. This paper describes the design and implementation of a new RLE algorithm based on data chunking and packing that exploits the Cray gather-scatter vector hardware and multiple processors. This approach reduces I/O and file storage requirements on average by an order of magnitude. Data intensive applications such as the integration of environmental and global climate models now become practical in a realistic time frame

Composition of chemical attractants affects trap catches of the Australian sheep blowfly, lucilia cuprina, and other blowflies

Numbers of Lucilia cuprina (Australian sheep blowfly), Chrysomya spp., and Calliphora spp. blowflies caught on sticky traps baited with various synthetic attractants or a standard liver/sodium sulfide attractant in western Queensland were recorded. Numbers of each genus collected were influenced by the composition of the chemical attractants. Attractant mixtures based on 2-mercaptoethanol, indole, butanoic/pentanoic acid, and a sodium sulfide solution gave 5- to 20-fold higher L. cuprina catches than the liver standard. These blends attracted similar numbers of Chrysomya spp. (0.85–2.7× ) and fewer Calliphora spp. (0.02–0.2× ) compared to the liver standard. These synthetic attractants were more effective and selective for L. cuprina than the standard liver/sodium sulfide attractant, and they can be packaged in controlled-release dispensers to generate constant, prolonged release of the attractant

Downscaling global information for regional benefit: Coupling spatial models at varying space and time scales

Every environmental activity to a large extent is dependent on climate as natural processes are intrinsically linked with the waxing and waning of the seasons. The goal is to integrate global seasonal climate forecasts with local environmental decision support systems within an operational framework to deliver community benefits. This framework is designed to support the downscaling of coarse resolution seasonal forecasts to drive biological or hydrological applications at the regional level. Some of the challenges and complexities in coupling spatial simulations operating at varying spatial and temporal resolutions will be discussed from several viewpoints, illustrating the value of multidisciplinary collaboration in a virtual team and benefits from the globalisation of research. This project demonstrates how a state Government is evolving an existing service to enhance the use of seasonal climate forecasts for sustainable environmental and natural resource management.Every environmental activity to a large extent is dependent on climate as natural processes are intrinsically linked with the waxing and waning of the seasons. The goal is to integrate global seasonal climate forecasts with local environmental decision support systems within an operational framework to deliver community benefits. This framework is designed to support the downscaling of coarse resolution seasonal forecasts to drive biological or hydrological applications at the regional level. Some of the challenges and complexities in coupling spatial simulations operating at varying spatial and temporal resolutions will be discussed from several viewpoints, illustrating the value of multidisciplinary collaboration in a virtual team and benefits from the globalisation of research. This project demonstrates how a state Government is evolving an existing service to enhance the use of seasonal climate forecasts for sustainable environmental and natural resource management

Composition of chemical attractants affects trap catches of the Australian sheep blowfly, lucilia cuprina, and other blowflies

Numbers of Lucilia cuprina (Australian sheep blowfly), Chrysomya spp., and Calliphora spp. blowflies caught on sticky traps baited with various synthetic attractants or a standard liver/sodium sulfide attractant in western Queensland were recorded. Numbers of each genus collected were influenced by the composition of the chemical attractants. Attractant mixtures based on 2-mercaptoethanol, indole, butanoic/pentanoic acid, and a sodium sulfide solution gave 5- to 20-fold higher L. cuprina catches than the liver standard. These blends attracted similar numbers of Chrysomya spp. (0.85–2.7× ) and fewer Calliphora spp. (0.02–0.2× ) compared to the liver standard. These synthetic attractants were more effective and selective for L. cuprina than the standard liver/sodium sulfide attractant, and they can be packaged in controlled-release dispensers to generate constant, prolonged release of the attractant