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

To optimize catches of Heliothis punctigera and H. armigera pheromone blends, dispenser and trap design have been evaluated and modified over a.7 year period. A laminated plastic lure loaded with appropriate pheromone blends was.found to give a high and prolonged attraction of males of both species. A.hollow cone (Texas) trap has given higher catches than the standard dry.funnel trap, but the latter was more robust and less expensive..A tendency has been shown for pheromone traps to over estimate the.proportion of .H. armigera in comparison to that found in light trap.catches and egg identification of the two species. GLC. analysis of.weathered lures indicated a more rapid release of aldehyde than acetate.components of pheromone blends . Departure of blends from the optimum ratio.is more likely to affect the efficiency of H. punctigera lures which.contain both components, than those of H. armigera lures which contain.only aldehydes

A contribution was made to the last ACGRA conference on "The duration.of insecticidal activity against Heliothis larvae on cotton". This paper.is primarily an update of the previous contribution and the more detailed.results published in Pesticide Science (Wilson et al 1983). In addition.tests have been conducted over the past two years on other insecticides.including those now coming into general use.

The term 'genetics' encompasses a group of disciplines which study aspects of evolution. the first of these, molecular genetics, examines DNA, the raw material of evolution, and its organisation into genes. Genes code for information which, when. expressed, gives rise to the characteristics of the organism. It is changes at this level which yield the variation necessary for evolution to occur.

In response to the development of resistance to pyrethroids by Heliothis armigera in 1983, an Insecticide management strategy was devised.in an attempt to prolong the field effectiveness of this and indeed, the other groups of Insecticides used against H. armigera on summer crops in Australia. Basically, the strategy allows the use of pyrethroids on only one generation of the four or five generations which can occur during the season. Control at other times relies on the rotation of unrelated chemical .groups (e.g. organophosphates. carbamates, endosulfan etc.). The strategy. was first Introduced in the 19R3/R4 season and was closely monitored in the Intensive cotton growing areas of the Namoi and Lower Gwydir valleys. This paper deals with the acceptance of the strategy in that area and the monitoring results for the first season.

Consultation with growers about their key areas of interest identified the need for highly localised information about managing nutrition and how the plant reacts under different temperature situations to assist with better management of limited water.

The next question was being able to access this local information in a quick and cost effective way. This project was developed from this background work. By utilising some existing local data, a method was sought to combine this existing work with new trial work to deliver for growers relevant and local data that meets their needs.

Following the trial of delivering this information in a booklet format, it was decided that annual data records should be maintained ensuring the delivery of relevant and local data to growers each year, including based on our local trials undertaken.

The trial of the canopy temp sensors will help growers to get a good look at the new technology and also build the database of benchmarking information for the CSIRO .