The aims of this trip were to initiate research on HaSV RNA designed to improve our ability to express insect viral genes in transgenic cotton, and to attend two important conferences relevant to the long-term biological control of major cotton pests like Helicoverpa armigera: the International Workshop on the Molecular Biology and Genetics of Lepidoptera (Crete) and the International Colloquium on Invertebrate Pathology and Microbial Control (Montpellier

Frontiers of Population Ecology Meeting program and abstracts

In March 1995 I attended two Keystone Symposia, "Frontiers of Plant Morphogenesis" and "Signal Transduction in Plants", held concurrently at Hilton Head Island, South Carolina, U.S.A. This was made possible by the Smith-White Travel Grant A ward that I received from the Genetics Society of Australia last year, and substantial assistance was obtained from the Cotton Research and Development Corporation

This project has supported a wide range of cotton programs based at Narrabri covering all CRDC funded projects during this period. It has ensured that the best management practices are adopted for the experimental areas and that the quality of field research complements the high research standards maintained by the research group.

Project Objectives: Part A: (i) To study the effect of wet/dry cycles with drying by evaporation alone in ameliorating degraded furrows in retained hill cotton (at the Fressor site). (ii) To quantify the soil structure changes in (i) and relate them to soil physical properties. Part B: (i) To study the relative effect of rotation crops (evaporation alone and no crops) in ameliorating degraded furrows in retained hill cotton (at the Leadbetter site). (ii) To quantify the structure changes in (i) and relate them to growing rotation crops.

This project followed on from the production of the SOILpak manual (A soil management package for cracking clays). It is essential to be able to recognise features of soil structure in order to be able to use the SOILpak manual effectively. The "Soil Management Training" project addressed this issue. It trained cotton consultants, extension personnel, farmers and agronomists, in the skills required to diagnose soil structural condition. The trainees now use these skills to make, or help cotton growers to make, informed soil tillage decisions. Decision support materials in the form of videos, stereoscopic images and field guides were produced as part of the project. These materials are now available for use by the trainees to train others. Increasing the skill level in soil diagnosis has allowed those making tillage and other soil management decisions to see the results of their management and soil trafficking policies. On farm decision making has been improved as a result.

Mr. Martin Dillon was not able to attend the congress, as it coincided with the birth of his son on 24 November 1993. However, Martin Dillon and Dr. Gary Fitt were co-authors with others, on two papers presented at the congress by Mr. Wayne Rochester. As well as being published in the conference proceedings, both papers were also selected for publication in a special edition of the journal Ecological Modelling, and are currently in press. Copies of the papers are attached. After notifying the CRDC, the travel funds were used for Mr. Martin Dillon to attend the 1994 Conference of the Ecological Society of Australia at Alice Springs, 28 - 30 September 1994. This conference included a special symposium on "Applied spatially dynamic modelling" which was of particular interest to Mr. Dillon and his co-author Mr. Wayne Rochester. A number of valuable contacts were made with Australian and international scientists interested in modelling the spatial dynamics of organisms. A poster paper and an oral presentation were presented at the meeting (abstracts are attached). There were no proceedings published from this conference.

To make the OZCOT cotton crop simulation model more robust and versatile; enabling it to be used for decision support in a broader range of applications and situations. This involved five specific objectives: 1. Improve the water balance component of the model. particularly the parts dealing with water movement in the soil profile. by incorporating the CERES water balance subroutines. 2. 3. 4. 5. Incorporate the soil nitrogen subroutines from CERES to allow simulation of nitrogen and organic matter dynamics in the soil. Develop an explicit carbon balance for the model in which photosynthesis produces dry matter which is then partitioned between organs. In the past, carbon balance has been modelled implicitly by using "carrying capacity" (bolls supported per metre of row) as a surrogate for photosynthetic capacity. Develop subroutines to model the uptake and distribution of nitrogen within the cotton plant. This will allow the model to respond dynamically to nitrogen supply, introducing the capacity for consideration of tactical nitrogen issues. It is also a necessary interface for connection to the soil nitrogen sub-model. Collect data on key developmental parameters which characterise the differences in fruiting dynamics between cotton cultivars. These model parameters allow a degree of cultivar sensitivity in the simulation output. The data will be used to maintain the models relevance to current cultivars and to test the importance of variation in these parameters for simulation output

The aim of the project, to enable cotton to be grown in experiments in the disciplines of breeding, agronomy and entomology by the CSIRO Cotton Research Unit at the Australian Cotton Research Institute, has been met Over the three years of CSP34C (ln/91-30/6/94) a series of agronomic, breeding and pest management studies were completed. An indication of the scale of research is detailed below with that for 1993/94.

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.