SUMMARY We have generated an antibody which is absolutely specific for H. armigera over H. punctigera. Specificity has been demonstrated in a number of ways. For example, the antigenic protein from H. armigera and its homologue from H. punctigera were purified and probed with the kit MAb. No detectable reaction was observed against H. puncti.gera under conditions where a very strong reaction was observed versus the H. armigera protein. The experiments indicate that a very high level of species-specificity is an inherent property of the kit antibody. We have incorporated the anti.body into a prototype ID kit which has now been tested under field conditions. The kit is not yet of commercial quality and reliability. Nevertheless, for eggs collected from the field at a single time and place, there is a high correlation between the % H. armigera detennined by the kit and as determined by rearing (Trowell et al. 1992). This indicates that the basic design of the kit is sound and further development is worthwhile. We are working on reliability problems which have been thrown up in the field tests and have made significant progress in overcoming them. The problems are of the kind normally encountered in development of this type of test kit Together with a partner experienced in immunodiagnostic production, we expect to be able to produce a kit of commercial quality

To develop, validate and implement a regional model of Helicoverpa population dynamics which considers the abundance, movement, oviposition, development and mortality of H.armigera and H.punctigera on all major hosts within a given region. The purpose is to provide an interactive simulation model which can predict the regional dynamics of Helicoverpa populations in response to climatic, biotic, and agronomic conditions.

During August 1990, in company with Dr Norm Thomson, Mr Reid visited a number of research institution and companies form California to Mississippi. The main purpose of the trip were to survey trends in US cotton breeding, to get to know American breeders personally, and to become more familiar with the US cotton belt.

I was invited to speak at the conference to give a paper at one of the sessions. My paper was entitled "Mechanical Problems in Soil/fool Interaction", and covered the soil mechanics of tillage and compaction by vehicle tyres and tracks. The talk was based on my work in the cotton industry over the last few years.

A 20 saw gin was bought for $13,000 from the USA. It was installed and fitted with a motor in time to be used in the 1991 harvest It operated satisfactorily throughout the 1991 season.

This project was concerned with the transfer of cotton fibre testing from the Division of Wool Research, Geelong Victoria to the Cotton Research Unit at Narrabri Agricultural Research Station (NARS). It involved the construction of a fibre testing laboratory within the CSIRO field shed, the purchase and installation of a Spinlab 900 series HVI length, strength and micronaire instrument by January 1989 and the purchase and installation of a Shirley Fineness Maturity Tester (FMT III) the following year. The project also called for the employment of casual staff to operate the equipment under the supervision of CRU staff and provided for the maintenance of the equipment.

The aim of this project was to develop tool/s to inform grower decision making with regards to Verticillium wilt. Verticillium wilt is caused by the soil-borne fungal pathogen Vertillicum dahliae. Once introduced to a field, V. dahliae is considered impossible to eradicate. Failure to control the build up of disease inoculum can result in very large yield losses and fields becoming unsuitable for cotton production. Reports from growers estimate yield losses range from 10–62 per cent. As there are no control options for Verticillium, recommended best management is to rotate out of cotton to non-host crops until levels of V. dahliae. sufficiently reduce. Understanding the risk of verticillium disease prior to planting would mean growers could make informed decisions about whether it was safe to go back to cotton, potentially preventing significant yield losses.

Key outcomes:

- Diversity of V.dahliae virulence even within strains is quite high and some Australian isolates can cause more severe damage compared to international isolates.

- The development of a V. dahliae specific inoculum quantification assay was extremely challenging and semi-successful. The molecular soil assay can detect V. dahliae and the sensitivity of detection was 10-30 ppg in naturally infected soil. This is not sensitive enough when one propagule per gram of soil is enough to cause disease in more severe strains. A disease matrix was developed to industry that provides a guide to disease risk.

- A methodology was developed to determine the strain (VCG) of V.dahliae in soil using a combination of the dry plating soil assay and sequencing.

- A plant tissue molecular assay was developed that is faster than traditional isolating techniques and is capable of diagnosing V. dahliae and providing VCG in a higher proportion of infected plants. This molecular tool means industry has ability to quickly diagnose Verticillium down to VCG and growers and consultants can quickly determine which strain of V.dahliae they have, enabling Verticillium risk to be factored into decision to grow cotton.