The objectives of this project were to sample Gossypium sturtianum (Sturt's Desert Rose) in the Flinders and Barrier Ranges and multiply the samples for research and conservation. The area for exploration forms the southern boundary of the genus. Specimen records from major herbaria were used. to plan the field trip. This was carried out 8-19 February, and samples of individual capsules were obtained from 23 sites. including the .three most southerly populations, and eight new populations. This represents a substantial sampling of a very rare plant. The typical habitat for the species was a well drained bank of a dry creek, protected from winter exposure and with local air drainage. Throughout the area of study. the plant was very rare. At about one third of the sites, only a single plant was found and only four sites had appreciable populations. Most populations showed little .sign of herbivore damage. Plants have been established from the seed samples in the glasshouse at Canberra and seed will be harvested, evaluated and processed for storage over the subsequent twelve months as part of the germplasm program

In this and a related project funded by ARC, four fungal isolates of each of two common species were compared for their effect on plant growth. From this research we have concluded that the variation within one species is as great as the variation between species of VAM fungi. The first aim was to develop our understanding of each fungus so that we could predict the effect that fungus would have on growth of cotton. The practical consequence of our work is that knowing the species of fungus present in a soil provides us with little capacity to predict how it will influence plant growth

This project focused on the control of nutgrass. Nutgrass (Cyperus rotundus) is considered to be the world's worst weed and inf es ts over 15% of the cotton growing area. Nutgrass adversely affects cotton by competition for light, nutrients and water, and indirectly through lint c ontamination. reduced irrigation efficiency and increased soil problems. The project assessed the effects of herbicides, cultivation and rotation crops on nutgrass control using a number of field experiments located throughout the NSW cotton area. Most of these experiments will run for at least 2 seasons. but only the results of the first season are covered in this report.

Aim: To investigate the sensitivity or tolerance of Australian cotton varieties to levels of UV-B expected to exist in the foreseeable future

To develop cotton varieties capable of germinating and establishing in cool soils, seed of Siokra S324 was mutated to induce variation. Ii. was anticipated that increased levels of unsaturated fatty acids in seed oil would lead to more rapid cotton-seed germination in cold soils, as had been observed in sunflowers.

The aim of this project is to.assess the efficacy of three new classes of hydrolase genes that might have insecticidal activity when introduced into transgenic cotton. These genes encode hydrolytic enzymes including lipases; phospholipases and phosphatases. Feeding studies on Heliothis armigera larvae indicate that crude preparations of these hydrolytic enzymes significantly retard the growth of these insects on a synthetic diet and may lead to larval death. More refined studies on purified proteins and isolated genes will be required to demonstrate the usefulness of these gens in insect control

The spatial variation in crop yield, and the field-based factors that contribute to it, is developing as a subject of importance to both the farming and wider communities. Increasing attention is being focused on the notion that agricurally productive land can be managed as a relatively homogeneous unit at the 'within-field' scale. Such an assumption may lead to inappropriate resource application and associated financial, environmental and social costs. The significance of these imposts, such as input waste, yield reduction and soil, water and air contamination has been identified in the Cotton Research and Development Corporation (CRDC) publications compiled by Anthony et al. (1992) and Hearn (1993). Preliminary research has prompted the proposal of site-specific management as a remedy to many of these environmental and resource-use inefficiency problems (Larsen & Robert 1991). Figure 1 outlines the simple rationale that justifies and supports site-specific management

To help coordinate and ensure good collaborative ties between these research groups and to broaden the understanding of soil salinity within the industry, the CRC initiated the development of a Strategic Plan on salinity research and management for the cotton growing areas of Australia. The following Plan complements the comprehensive salinity management strategy document of NSW Agriculture. This Plan's main purpose is to: a) briefly state the current extent of soil salinity and shallow water tables within the cotton growing areas b) raise awareness and educate the industry as to the potential threat of soil salinity c) provide a framework for best management strategies to minimise the threat or spread of soil salinity d) identify key gaps in knowledge to ascertain the potential threat to cotton production e) describe and outline the linkages between current work in progress provide a time frame for the completion of key actions

The Cotton Research and Development Corporation Project US05C aims to provide techniques for the rapid assessment of rootzone salinity for cotton growing soil profiles of northern New South Wales and south-eastern Queensland. Many of the techniques currently being investigated in the lower Namoi valley of NSW, where instigated at the United States Salinity Laboratory (i.e., EM38). The laboratory is located in the city of Riverside in southern California, approximately 60 miles east of downtown Los Angeles

The Australlan Entomological Society Conference in Cairns from 3 to 8 July 19S3, was attended by Melina Miies (Department of Entomology, UQ).