At the 1982 Australian Cotton Growers' Research Conference the effects of land preparation at different soi1 water contents on soil structure and cotton growth was reported. In summary, land preparation on 'wet' rather than 'dry' soil led to (1) a significant reduction in the amount of water available to cotton plants, (ii) strong changes in soil structure visible in the soil profile, and (iii) smaller cotton plants with up to 50% fewer green bolls.

In recent years sap-sucking bugs have been associated with early season damage.to cotton crops in most of the production centres in New South Wales and Queensland. Four species have been included in this pest complex: the green mirid (Creontiades dilutus), the apple dimpling (Campylomma livida),.the brown smudge bug (Deraeocoris signatus) and the rutherglen bug (Nysius.vinitor). The University of Queensland has conducted a number of preliminary studies on these bugs, concentrating on the green mirid. The studies conducted prior to the 1982-83 season have been discussed by Bishop (1980).and Adams and Pyke (1982). This paper summarises some of the results and observations made since 1982 from field cage, glasshouse and laboratory studies as well as unsprayed and commercial cotton crops.

Intense selection pressure has led to the development of insecticide resistance

At Narrabri we are continuing our breeding program to develop locally adapted early maturing varieties. At present there are no early varieties available commercially in Australia hut we feel that they could play an important role

Catches in pheromone traps can provide two types of information of interest to growers and researchers. Firstly, trap catches may directly indicate the abundance of moths in an area and hence the level of egg laying.in the crop. Unfortunately there doesn't appear to be any close association. Despite accounting for the effects of temperature and wind speed, Rothschild.et al (1981) found the relationship between trap catches (in cannister traps).and egg numbers was too variable on a day to day basis to be a reliable indicator of oviposition activity. Twine (1982), using texas traps

Commercial cotton crops in the major New South Wales production areas were inspected during the 1983/84 growing season. The purpose of these surveys was to assess the relative distribution, incidence and severity of the various diseases which were found to be present. Information obtained during these surveys can give direction for the work of plant pathologists plant breeders and extension personnel and can also provide a basis for relating disease occurrence and severity to factors such as soil and climatic conditions or changes in cultural practices or crop cultivar

Resistance is seen as a manifestation of the most basic property of life, namely the capacity of organisms to evolve in response to changing environmental conditions and to adapt to new circumstances. Despite the detection of severe resistance as far back as the l940's-60's, the relative abundance of new insecticides in the 1950's, 60's and 70's circumvented the need to delay or prevent resistance. New chemicals were always available.to replace those to which the pests had become resistant. Only recently has the realisation emerged that the discovery of new insecticides will not keep pace with the development of resistance in many of our major insect pest species.

Bacterial blight [Xanthomonas campestris pv. malvacearum (Smith 1901) Dye.1972], of cotton produces angular spots on leaves and squares, causes defoliation, lesions on sterns and bolls and reduces yield. Downward spread of the disease from the principal veins of the leaf blade or by direct infection of lateral branches results in the black arm symptom. This is the most serious form of bacterial blight and occurs in seasons most favourable to the pathogen or when crops have been severely stressed. Each season bacterial blight is present in varying levels of severity in the majority of crops. The grower.is most aware of this disease by the damage it causes to the boll. This consists of discolouration of the lint, destruction of one or more locules,.bolls failing to open and increased boll drop.

The high quality cotton Namcala and its predecessor Hopicala have traditionally been grown on small percentages of the Australian cotton acreage (Mainly in NSW) as an alternative to the high yielding varieties such as Deltapine smooth leaf. Deltapine 16 and recently Deltapine 61

In agriculture we often hear reports of new wonder varieties that are about.to revolutionise agriculture, yet when these varieties are released, if.indeed they are released, they seem to fall far short of the publicity that.heralded them. A major technological break-through in variety development.is rare. Most improvements cane in rather small steps. In the next few.years improvements will be in small but positive steps..It is my endeavour here to present you with an objective assessment of what.you, the grower, can hope to expect from cotton varieties in the near future