Identifying the IPM needs of the Fresh market Tomato Industry in Northern Victoria Sze Flett et a I Dept of Natural Resources and Environment Project Number: VG98150 VG98150 This report is published by Horticulture Australia Ltd to pass on information concerning horticultural research and development undertaken for the vegetable industry. The research contained in this report was funded by Horticulture Australia Ltd with the financial support of Northern Victoria Fresh Tomato Industry Development Committee. All expressions of opinion are not to be regarded as expressing the opinion of Horticulture Australia Ltd or any authority of the Australian Government. The Company and the Australian Government accept no responsibility for any of the opinions or the accuracy of the information contained in this report and readers should rely upon their own enquiries in making decisions concerning their own interests. ISBN 0 7341 0577 0 Published and distributed by: Horticultural Australia Ltd Level 1 50 Carrington Street Sydney NSW 2000 Telephone: (02) 8295 2300 Fax: (02) 8295 2399 E-Mail: [email protected] © Copyright 2003 Horticulture Australia The Horticultural Research and Development Corporation Project VG98150 (Completion date: 30th June 2002) Identifying the IPM needs of the Fresh Market Tomato Industry in Northern Victoria Final Report Sze Flett et al Project SF97006 Principal Investigator Dr Sze Flett Contact Details NRE Tatura Private Bag 1 Ferguson Road TATURA VIC 3616 Tel: (03) 5833 5222 Fax: (03) 5833 5299 Email: sze.flett(5)nre.vic.gov.au Project Team Sze Flett (10%), Cathy Mansfield (50%), Joanne Dawson (100%)-NRE Tatura Purpose of the Report This report fulfils the requirements of Horticulture Australia Limited for a final report on project VG98150. Aims of this project were: a) To investigate the incidence and management of bacterial canker. b) To investigate current pest and disease management practices Funding Acknowledgments The researchers acknowledge the financial support for this project from Horticulture Australia Limited, Northern Victorian Fresh Tomato Industry Development Committee and the Department of Natural Resources and Environment. Date of the report November 2002 Disclaimer Any recommendations contained in this publication do not necessarily represent current HRDC policy. No person should act on the basis of the contents of this publication, whether as to matters of fact or opinion or other content, without first obtaining specific, independent professional advice in respect of the matters set out in this publication. The advice provided in this publication is intended as a source of information only. The State of Victoria and its employees do not guarantee that the publication is without flaw of any kind or is wholly appropriate for your particular purposes and therefore disclaims all liability for any error, loss or other consequence which may arise from you relying on any information in this publication. Contents Media Summary 1 Technical Summary 2 Introduction 4 Materials and Methods 6 1. Investigating the incidence and management of bacterial canker in fresh tomatoes... 6 1.1 Bacterial Canker Survey 6 1.2 Bacterial Canker - development and implementation of disease management strategies 6 2. Investigating current pest and disease management practices of the fresh market tomato industry 7 2.1 Incidence and impact of tomato pests, diseases and beneficials 7 2.11 Monitoring 7 2.12 Level of parasitism of Helicoverpa in fresh tomato crops 8 2.13 Harvest assessments 8 3. Developing a Helicoverpa monitoring technique for the fresh tomato industry 10 4. Chemical usage in the fresh market tomato industry 11 4.1 Current chemical use and its affects on pests and diseases 11 4.2 Resistance testing on Helicoverpa 11 4.3 Preliminary Targeted Chemical trial 11 Results 12 1. Investigating the incidence and management of bacterial canker on fresh market tomatoes 12 1.1 Bacterial Canker Survey 12 1.2 Bacterial Canker - development and implementation of disease management strategies 12 2. Investigating current pest and disease management... practices of the fresh market tomato industry 13 2.1 Incidence and impact of tomato pests, diseases and beneficials 13 2.11 Pests 13 2.12 Diseases 15 2.13 Beneficials 16 2.14 Physiological and nutritional disorders 18 2.15 Overview of fruit damage from harvest assessments 18 3. Developing a Helicoverpa monitoring technique for the fresh tomato industry 20 4. Chemical Usage in the fresh market tomato industry 21 4.1 Current chemical use and its affects on pests and disease 21 4.2 Resistance testing on Helicoverpa 22 4.3 Preliminary targeted chemical trial 23 Discussion 24 Technology Transfer 27 Recommendations 29 Acknowledgments 30 Appendices 31 Appendix 1 32 Bacterial Canker Report 32 Media Summary The Victorian fresh tomato industry currently relies on routine chemical applications to maintain a high quality product. However, in order to meet consumer demands for 'clean, green' blemish free products, for both domestic and export markets, the industry is keen to explore the potential of Integrated Pest Management (IPM). This project was conducted to provide baseline data on pests and diseases in fresh market crops and quantifying the associated fruit loss, which are essential for the development of an effective IPM strategy. Studies on the parasitism of Helicoverpa by the parasitic wasp Trichogramma were also conducted. Our results showed that up to 50% of the Helicoverpa was parasitised during the growing season. This project investigated current grower practices to control pests and diseases and their impact on yields and pest pressures. Results showed that current practices could lead to increased risk of insecticide resistance developing in Helicoverpa (otherwise known as Tomato Grub). Our research suggests that modification of current practices, including improved timing of chemical applications to target pests when they are in high numbers and at the most susceptible stage of the life cycle may maximise pest control and ensure long term environmental sustainability. This project emphasises the need for grower awareness of pest and disease monitoring as a tool to target control measures to minimise crop damage. To promote industry awareness of the project outcomes nine presentations and two workshops were conducted betweenl999 and 2002. Two posters aimed at providing a pictorial guide to tomato pests and diseases were developed and distributed to all growers. Based on the findings of this project, a new project titled 'Integrated crop management of fresh market tomatoes', project VX02013, will commence in October 2002. 1 Technical Summary The Victorian fresh market tomato industry does not currently practice Integrated Pest Management (IPM). Spray programs based on routine chemical apphcations, every 7-10 days, are used to manage pests and diseases in this industry. This practice results in unnecessary spray applications and misses key insecticide application windows leading to an increase in production costs and high fruit damage. IPM uses a range of techniques to effectively control pests and diseases. A variety of biological, chemical and cultural methods provide growers with more options for controlling pests and diseases than their current spray programs. To successfully manage pests and diseases, information is needed on the key pests and diseases, their pressures and the level of fruit damage, current chemical usage and the levels of beneficial insects. The project obtained information by monitoring tomato crops, harvest assessments and by assessing chemical spray records for timing of chemical applications and effectiveness of those applications in reducing pest numbers. The primary pest in fresh market crops was Helicoverpa. As only a few tomato crops were monitored each season the full impact of secondary pests may not have been observed. Secondary pests may have been more of a problem in other tomato crops. The other pests found were thrips, leafhoppers, aphids and mites. The main disease problem was bacterial canker. Other disease problems were powdery mildew, big bud, bacterial speck and tomato spotted wilt virus. Other disorders such as scarring, blossom end rot, zippering and catface may cause up to 19% fruit damage at harvest. This project found gaps in growers spray programs, which coincided with high oviposition by Helicoverpa. Helicoverpa needs to be targeted at its most vulnerable stage, ie the first instar larvae. For growers to target this vulnerable life stage, they need to be monitoring the crops. Improving the timing of chemical applications would improve the impact of chemical applications on pest populations. Growers' spray records also showed that the same chemical group was being applied over several generations of Helicoverpa. This practice can lead to the development of Helicoverpa resistance to insecticides. A preliminary study on resistance in Helicoverpa was undertaken in this project. Resistance testing of Helicoverpa caterpillars to two commonly used chemical groups, pyrethroids and carbamates, was conducted. In the laboratory, there was Helicoverpa resistance to both of these commonly used chemical groups. Resistance was demonstrated when Helicoverpa was sprayed with insecticides from these chemical groups at doses that usually cause mortality in Helicoverpa. In order for growers to reduce the risk of resistance problems arising in the future they need to change the way they spray so that they are rotating groups of chemicals