Farmers have probably always realised that soil is alive. Good soil seems to have certain intangible qualities, over and above its physical structure and chemistry. There is something special about topsoil. What are these intangible qualities? We all know that microorganisms in the soil can cause disease. However, in the last 25 years scientists have started to recognise the importance of some very helpful soil inhabitants, especially the vesicular arbuscular mycorrhizal (VAM) fungi and beneficial bacteria.

The cotton whitefly Bemisia tabaci is a serious pest of fibre and horticultural and ornamental crops worldwide. When present in sufficient numbers, it can cause extensive damage through direct feeding, the production of large quantities of honeydew and as a vector of many viruses. A new biotype was first identified in the USA, known as the B-type or poinsettia strain. Overseas, the B-type B, fabric is a primary pest on cotton, other vegetable crops (curcubits, tomatoes, rock melons) and ornamentals. This strain is extremely virulent, insecticide resistant, adapts to temperate climates and has a host range of over 500 plants. B-biotype B.tabaci were detected for the first time in Australia in October 1994 in both Darwin and Tamworth. During 1994/95, the Cotton Research and Development Corporation funded a survey to determine the current Australian distribution of B-type B. tabaci and its insecticide resistance status. Investigations suggest that the B-biotype B.tabaci was first introduced into Australia in late 1993, via poinsettias which were legally imported from California in the United States to Coffs Harbour (NSW). Our surveys show that this whitefly is well established and widespread in eastern Australia and eradication is not considered possible. The whitefly has not yet been detected in Victoria, South Australia or Western Australia, however it is very likely that infested plants have been sent to these states.

This talk is heavily dependant on slides, so the following 1s really only a &quote;background&quote; paper. My approach when giving such a talk to canegrowers, has been to devote the first half to explaining why it is essential that an industry be seen to be environmentally sensitive. If you, the grower ( be it cane or cotton ) don't appreciate that need, you are not likely to listen with any degree of interest. I've heard Maree McCaskill, Executive Director of the Australian Cotton Foundation speak at a Canegrowers' conference, and imagine many of you are already aware of the public relations benefits of such an approach.

In Australia the primary pesticide for control of heliothis in cotton is the organochlorine endosulfan. In recent years it bus been supplemented by a variety of other pesticides including organophosphates, carbarnates, pyrethroids and trisect growth regulators in an effort to reduce the level of pesticide resistance. Endosulfan is toxic to aquatic life (either as the two parent isomers or as the breakdown product, endosulfan sulfate), with fish being reported as highly sensitive to the chemical. Concern over the environmental fate of cotton pesticides in the late 1980s, led the New South Wales Department of Land and Water Conservation DLWC) to undertake in 1992 biological monitoring of aquatic macro invertebrates to assess the impact of irrigated agriculture on the rivers in the north west region of New South Wales (Figure I). The work forms part of the Central and North West Regions Water Quality Program (CT. IWRWQP) which is jointly funded by the DLWC and the water users of the Gwydir, Macquarie, Namoi and Border Rivers valleys. The other major components of the CN\NRWQP focus on pesticide, physico-chemical and nutrient monitoring.

This is a Cotton Research and Development Corporation funded three year project toconsider the follong areas and address the issues developed below.Aims:To continue and develop the work begun in the existing project which focuses on residue handling in back to back cotton and rotation crops while optimising the control of diapausing heliothis pupaeTo visit growing areas (irrigated and rainfed) and confirm a basis for other machitiery needs in the industry, including planting and cultivation equipmentField test equipment changesSeek backing from commercial entities to limit funding drain of research moneysPursue the involvement of commercial manufacturers where appropriate to help in the adoption of improved technology.To monitor commercialisation of a fully tested computer based guidance system

Controlling heliothine caterpillars presents an ever greater challenge for the Australian cotton industry. The bollworm, Helicoverpa armigera, creates especial problems by evolving resistance to most major chemical insecticides. Chemical insecticides are furthermore associated with environmental dangers and increased production costs due to the need to overcome resistance.

Crop rotations, including wheat and sorghum, can provide stubble cover to protectthe soil while cotton is establishing. Controlled traffic layouts have the potential to evenly distribute runoff over the field and prevents concentrations in rill lines. Associated with controlled traffic, minimum tillage and soil compaction control can increase infiltration and reduce runoff. An experiment was established in 1993 to study the impacts of controlled traffic, using a bed and furrow system, on runoff and soil loss.

Cotton fibres are differentiated from single cells of the outer epidermis of ovules and originate at, or soon after, anthesis (Ramsey and Berlin, 1976). Cotton fibre differentiation, characterised by a precise and synchronous growth and uncomplicated by cell division, is a suitable experimental system in which to study cellular and developmental events. In addition, the commercial desirability of long fibres has stimulated studies of the factors involved in controlling the extent of fibre growth. The main aim of this project was to isolate and characterise cDNA clones of mRNAs which are specific to, or important in, cotton fibre development.

Tile green mirid, Creontiades dilutus (Stal) is one of the early season pests of cotton. This insect was identified in the late 1970's and can cause considerable damage to cotton seedlings and squares resulting in significant delays in growth and maturity of the plant (Bishop 1980; Adams and Pyke, 1982). Currently green minds are suppressed by synthetic insecticide sprays targeted for the control of Helicoverpa spp. in commercial cotton. With the proposed introduction of Bt cotton, green mirids are going to be very important since chemical sprays against Helicoverpa spp. Are expected to be reduced (Fitt, pers. communication). Despite the importance of the green mirid within the Australian cotton industry, there is no detailed information on the life cycle and general biology of this insect. A detailed biological information can provide a basis for ecological studies and the development of a sustainable pest control system. We report here the life cycle, oviposition behaviour, and the pest status of the green mind.

In developing a water management plan, f m water use efficiency can be broken down into three segments - plant, agronomic and irrigation efficiency. This paper will briefly discuss important aspects which can effect plant water use but mainly concentrate on water management efficiencies (agronomic and irrigation fallow efficiency). Topics relevant to both irrigation and dryland cotton production are discussed