Nitrification inhibitors were successfully used to improve the recovery of fertilizer N in the irrigated cotton-growing system. By slowing the rate of nitrification of applied ammonium-N, it was shown that the loss of N through denitrification was limited by the reduced concentration of nitrate in the soil. The effectiveness of recognised and experimental nitrification inhibitors to inhibit nitrification and reduce N loss through denitrification were compared in field and laboratory experiments. The more effective inhibitors (2-ethynylpyridine (2-EP), Terrazole and N-Serve) were able to reUird nitrification for more than 8 weeks. They also improved N fertilizer recovery (from 35 to 50% in one situation) and enabled the cotton crops to better utilise fertilizer N where denitrification loss was severe. In some instances, lint yields were increased significantly (up to 18%) to where the profitability of cotton-growing was substantially improved.

A new glasshouse was constructed at Narrabri to enable an expansion of the backcrossing of genetically engineered characters into CSIRO cotton varieties. The glasshouse was constructed and in operation within three months

The Second Canberra Bacillus thuringiensis Meeting was held in the Manning Clark lecture theatre complex at the Australian National University from 21st to 23rd September 1993. The Meeting was organised by the CSIRO Division of Entomology with financial support from R&D Corporations (CRDC, RIRDC), AIDAB. The British Council and 11 Bt production and distribution companies. It was attended by 120 registrants. including 29 from 10 other countries in Asia, Europe. New Zealand and North America. The registrants were drawn from research institutions, universities, commercial interests, regulatory bodies. and R&D Corporations. The opening address by Professor B.A. Federici. University of California Riverside. provided a global view of knowledge of Bacillus thuri.ngiensis (Bt) and its various uses and opportunities for expansion of those uses. The 19 invited papers. 13 contributed papers and 13 posters explored details of the mode of action of Bt toxins, resistance to Bt toxins, novel toxins, production and application technologies. use of Bt genes in transgenic organisms, and conventional spray usage of Bt. Bt in transgenic plants. the social and environmental impact of Bt. and regulation of Bt products were the subject of extended discussion forums.

The anisotropic nature of the soil continuum does not lend itself to classification schemes constructed as many are by predetermined hierachical classes. Membership to classes are hard and are hence unable to consider the reality of the continuum, which ultimately manifests itself in the resultant soil map which delineates areas of supposed similarity. Further, the soil profile acts as the individual which itself varies vertically, with depth. In the following report the rather novel approach of fuzzy classification or continuous classification is used to classify individual soil layers from the lower Namoi Valley in an attempt to better represent the anisotropy of the soil continuum. Essentially 1419 chemical soil layers with particle siza analysis data taken from specified depths within 227 soil profiles were classified using fuzzy kmeans. Ten soil layer classes or clusters were identified within the data, which were then reclassified to consider an additional extrade layer class or outlier class. When reassembled into their constituent profiles the layers from these classes formed readilly identifiable profile sequences which were classified accordingly. The resultant proflies once mapped corellated well with field perceptions of the geology and geomorphology of the lower Namoi Valley. As with the classificatory difficulties associated with soil classification many land evaluations are constructed in a similar fashion in which subjective cut offs are used to delimit areas or tracts of land which are better suited than others. Continuous classification was applied to a quantitative land evaluation introduced for New South Wales for wide variety of land utilisations by using a function which by its nature produces a continuous membership between two classes, suitable and non suitable to any particular land utilisation. The following report illustates the potential of such a classification scheme which could be used in a number of disciplines where the continuous nature of a medium can be expressed and has potentially many practical applications. As a consequence of the work undertaken and presented within this report new directions and technologies are suggested which could be undertaken for further research

The work has identified condensed tannin (CT) as occurring in cottonseed hulls but not in cottonseed kernels. Approximately 20% of the CT in cottonseed hulls is extractable and 80% is bound to protein and fibre. This contrasts with forage plants, where 75% of CT is extractable and 25% is bound. As Australian cottonseed meal (CSM) contains some hulls, this explains its content of CT (0.8-1.6% DM). Animal nutrition experiments were then conducted to study the effect of adding hulls upon the digestion and availability of kernel protein to ruminant and monogastric animals. During 1993 and 1994 all experiments were done with solvent-extracted unheated kernel.

This project commenced on the 1st July, 1993. Since that time the following has occurred

I have prepared these notes for our meeting of July 2S. They describe some of the activity of many people who have given us insight into the processing characteristics of eight major cotton varieties grown at Narrabri and Merah North in the Namoi valley. As the industrial practice of blending bales into a mix always loses the varieties' identity, the trial provided a rare look at the pure varieties in yam and fabric form, u well as their behaviour throughout spinning, knitting, preparation and dyeing. The possibility of converting them into varietal garmentss remains, but is beyond the present budget.

A number of laboratory experiments have been run since 1989 to address the area of distribution variation. Of these experiments, the latest two (A and B) have compared 10 different metering and distribution systems, compiled of current commercial metering systems fitted with their commercial distribution/manifolds systems and the same metering systems fitted with a range of prototype manifold distributors or other attachments developed during the previous experimental phase

This project supports the maintenance of fibre testing facilities at the Australian Cotton Research Institute. The major activities are associated with the cotton breeding program with close to 20,000 samples being processed each year in the three months after harvest. This procedure enables early generation testing of fibre properties where inferior types can be culled from further testing.,

Objectives To continue the development and validation of a series of micro-computer based decision support packages (initially hydroLOGIC and entomoLOGIC) under the generic name CottonLOGIC.,