AP113 Developing an eradication strategy for codling moth. Bill Woods Agriculture Western Australia

Transcription

1 AP113 Developing an eradication strategy for codling moth Bill Woods Agriculture Western Australia

2 API 13 This report is pubushed by the Horticultural Research and Development Corporation to pass on information concerning horticultural research and development undertaken for the apple and pear industry. The research contained in this report was funded by the Horticultural Research and Development with the support of the WA Fruit Growing Industry Trust Fund. All expressions of opinion are not to be regarded as expressing the opinion of the Horticultural Research and Development Corporation or any authority of the Australian Government. The Corporation 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. Cover price: $20.00 HRDC ISBN Pubhshed and distributed by: Horticultural Research & Development Corporation Level 6 7 Merriwa Street Gordon NSW 2072 Telephone: (02) Fax: (02) hrdc@hrdc.gov.au Copyright 1997 HRDVC HORTICULTURAL RESEARCH & DEVELOPMENT CORPORATION Partnership in horticulture

3 Table of Contents Summary PI Recommendations P2 Technical Report P3-5 Figures 1-8 P6-10 Appendix 1 Pll, 12 Appendix 2 PI 3, 14 Appendix 3 PI5, 19

4 1. Summary (1) Multi-Pher traps last longer and maintain moths in better condition for identification, but catch less moths and are more expensive than Delta traps. (2) Delta traps can be made inexpensively using local materials. The major part of the cost is for the pheromone. (3) To be effective a trapping grid must be thorough. A skeleton grid gives a false sense of security. (4) Neglected orchards harbour pests. They should be removed if possible. (5) Eradication plans should be worked out in advance rather than after a pest is established. 1 -

5 Recommendations (1) Extension/adoption The Western Australian pome fruit industry needs to budget to finance an early warning trapping system for Codling moth and to finance any fiiture eradication programs. (2) Directions of future research The pome fruit industry Australia wide needs to be looking at developing early warning systems and eradication plans for key overseas pests not yet in Australia. New pests will enter Australia. The choice is eradicate or live with them. (3) Financial/commercial benefits The earlier an exotic pest outbreak is discovered the more likely eradication is to be successful and the less it is going to cost. 2-

6 3. Technical Report Introduction Western Australia is separated from the rest of Australia by desert and because of this separation and strong quarantine barriers, some pests present in the Eastern states have not established a foothold in W.A. Examples are pests such as Oriental Fruit Moth, Queensland Fruit fly. Codling moth. Phylloxera and European Red Mite. Periodic outbreaks occur but to date these have been eradicated. Before this project was commenced an outbreak of Qfly had been found in W.A. As no early warning system was in place the pest was well established before found. It was successfully eradicated but at a cost of over $7 million. Codhng moth seemed a likely candidate for introduction to W.A. Not only had it been introduced 18 times in the past but increased tourist traffic increased the likelihood of this happening again. The cost/benefit of eradicating Codling moth was also likely to be favourable because of the high cost of control and the value of new apple varieties such as Pink Lady and Sundowner. Therefore the aim of the project was to develop and fine tune an early warning system against this pest, utilising sex pheromone traps. We also planned to prepare a contingency plan for eradication should a Codling moth infestation be found, and to simulate an outbreak in the field to test eradication procedures. The project commenced in June Pheromone traps were tested in the spring/summer of 1992 and Before we could simulate an outbreak a real one was found in January 1993 at Bridgetown. We quickly had to put into place an eradication strategy. What started as a $5,000 p.a. research project ended as a multi million dollar eradication program. Materials & Methods Mr Woods travelled to New South Wales in January 1992 to test two different types of Codling moth traps; the non-sticky "Multi-Pher" and the sticky Agrisense "Delta" trap (Fig. 1). Testing was carried out in apple orchards at Bathurst and Orange with the cooperation of Mr G. Thwaite, Senior Entomologist, Department of Agriculture, Orange Moths were attracted to both traps by a rubber septa impregnated with Agrisense' sex pheromone which attracts the male moth. In the triangular shaped cardboard Delta traps moths were caught on the sticky, polybutane base. In the plastic Multi-Pher traps moths were killed by a small section of pest strip which releases the pesticide dichlorvos. Long life Delta traps can be used for a couple of seasons whilst Multi-Pher traps have a longer life but are more expensive to purchase initially. The delivered cost of Delta traps was $7.50 and of Multi-Pher $ In general reusable Delta traps are approximately half the cost of Multi-Pher traps. -3-

7 Orchards with a history of bad Codling moth infestations were used in the trials. Five traps of each type were tested at each site. Delta traps were ahemated with Multi-Pher traps along a row of apples. Traps were rotated one position each week, checked weekly for seven weeks and the moth catch compared. Results and Discussion Although Multi-Pher traps caught 70% less moths than the Delta traps, moths were in better condition and this made moth identification more reliable (Table 1). This is important when staff have had little or no previous experience with a pest. Table 1. Moths caught in Delta (D) and Multi-Pher (M) pheromone traps in apple orchards inn.s.w. Orange Date Total Trap D M D M D M D M D M D M D M D M Total Bathurst Date : Total Trap D M D M D M D M D M D M D M D M * Total Therefore a mixed grid of Multi-Pher/Delta traps was placed out in key orchard areas in W.A. in spring of 1992 Fifteen traps were placed in the Manjimup/Bridgetown area, fifteen in Donnybrook and fifteen in the Perth hills. These traps were all placed on commercial orchards. -4-

8 In January 1993 Codling moth larvae were discovered in apples on a hobby farm at Bridgetown (Fig. 2). Subsequent inspections found neglected orchards to be severely infested (up to 70% infestation) (Fig. 3). No Codling moth were found on the commercial orchards in the Bridgetown area where we had 3 traps but when a much more intensive trapping grid was put in place moths were trapped only 200 metres from such an orchard. The trapping grid obviously did not give sufficient early warning of Codling moth infestations as we concentrated on commercial orchards when neglected orchards, backyards and hobby farms were the focii of the Bridgetown infestation. After Codling moth was found in Bridgetown an eradication program was commenced (Appendix 2). An important part of the program was trapping both in Bridgetown and in other areas of the state (Appendix 3). At first we used off the shelf Delta (Fig. 4) and Multi-Pher traps but due to cost constraints we soon began to manufacture our own traps based on a CSIRO/NSW Agriculture design (Fig. 5) (Thwaite : pes.comm.). Traps (Fig. 6) were made locally at a sheltered workshop at a cost of 50 cents per trap (Fig. 7). Although we purchased pheromone in bulk it still remained the major cost of the trap ($1.20 per lure). Traps and pheromone were replaced monthly. Locally made traps proved to be reliable and moth identification was not a problem when traps were checked regularly (Fig. 8). To give eflfective warning for Codling moth infestations in the fijture both neglected and commercial orchards need to be targeted. Where possible neglected orchards should be removed. Trapping in these orchards should be carried out by government agencies with grower funding. Commercial orchards should be trapped by the growers themselves with traps supplied at a cost from a central source. A compromise always exists between extent of trapping and cost. The more traps the higher the certainty of detection but also the higher the cost. A full risk analysis needs to be carried out to determine what trapping regime is appropriate and what degree of risk is acceptable. The Codling moth eradication campaign began with little warning. Eradication plans had to be prepared under great pressure in a short time. No local media material on Codling moth was available and had to be produced quickly (Appendix 3). However, experience gained from the Qfly eradication program, this project and the expertise of Graham Thwaite stood us in good stead and the program seems to be on track for eradication. Acknowledgements Graham Thwaite freely gave his very valuable time and expertise to help with this project. The project was initially flinded by the W. A. Fruit Industry Trust Fund with matching funding from HRDC. -5-

9 Fig. 1 (a): Multi-Pher trap (b): Graham Thwaite checks Agrisense Delta trap at Orange, NSW

10 Fig. 2. APB officer Patrick Walsh checks a Muhi-Pher trap at the hobby farm where Codling moth wasfirstfound in Bridgetown. A trap was placed in this orchard after fruit damage suggested Codling moth attack, and a trapped moth confirmed Codling moth presence. -7-

11 Fig. 3. Neglected orchard at Bridgetown (February 1993). Thirty five percent of apples from this orchard were infested with Codling moth. Fig. 4. Bill Woods and Dr Nic Monzu check Agrisense Delta trap in neglected orchard at Bridgetown. Note apple tree poking out from bracken.

12 Fig. 5. CSIRO/NSW Agriculture Delta trap on which W.A. model was based. Fig. 6. W.A. Delta trap made from 2L orange juice carton -9-

13 Fig. 7. Making Delta traps at Activ Industries shehered workshop at Manjimup, W.A.. Fig. 8. Debbie Thompson changing Deha trap in neglected orchard near Bridgetown - 10-

14 '., ^ Appendix 1 Paper presented to Australian Entomological Society Annual Conference in Adelaide, September J.i- " i 11

15 DEVELOPMENT OF A PROTOCOL FOR ERADICATION OF CODLING MOTH FROM WESTERN AUSTRALIA Bill Woods and Graham Thwaite Agriculture Western Australia, N.S.W. Agriculture In late January 1993 Codling moth was found at Bridgetown in Western Australia. Western Australia and Japan are the only major apple producers free of this pest, and it was necessary to develop a protocol for its eradication. The protocol was initially developed in February 1993 and was modified to deal with another outbreak discovered at Albany in April The protocol outline the steps required to accomplish the two main aims of the program ; firstly containment to Bridgetown and Albany areas and secondly eradication from Western Australia. Pheromone trapping and fruit dissection has been used to measure the progress of the program. Containment was accomplished by restriction on fruit movement from the quarantine areas. The placement of quarantine checkpoints on roads leaving the area in the first year ensured movement guidelines were adhered to. Severe restrictions were placed on the sale of both pome and stone fruit in year one. These restrictions were slightly relaced in year two. Fruit and tree removal and destruction are the major components of the eradication strategy. In the first year all stone and pome fruit from backyard orchards was collected and destroyed. In year two pome fruit from backyard growers was stripped and destroyed. Fruit removed was buried in pits and covered with at least a metre of soil. In year one fruit was stripped from 30,000 trees. Over 15,000 trees have been removed and burned in the program to date. Trunk scraping and banding was used on over 4,000 younger or smaller trees. The eradication program appears to be running to schedule. A concerted publicity campaign and the use of 2,000 pheromone traps has not detected any more infestations outside the Bridgetown and Albany regions. Only 13 moths were caught from September to December 1993, and one since that date despite the presence of over 500 traps in the Bridgetown area. This compares with 140 moths caught in February and March Inspection and dissection of over 50,000 fruit yielded only 2 small larvae in December 1993 and none since that date. At Albany no moths were caught in traps and no larvae found in dissected fruit. - 12

16 Appendix 2 Summary of Codling moth trapping information - 13-

17 1993/94 SEASON TOWNS Albany Bridgetown Bunbury Esperance Kalgoorlie Katanning Manjimup Narrogin Northam Perth Total NUMBER OF TRAPS /95 SEASON TOWNS Albany Bridgetown Donnybrook Manjimup Perth and Hills Total NUMBER OF TRAPS

18 CODLING MOTH Adult codling moth (insert actual size) Infested apples showing codling moth damage Codling moth larve leaving apple, note frass near exit hole Larvae tunnel into the fruit, eat the seeds and then tunnel out again. Larva pupate under barl<. Large photo of moth by C. Bower (t^sw Agriculture). All others by Robyn Knox.

19 CODLING MOTH What you should know about codling moth Codling moths are found in all the world's major apple and pear growing areas, except Japan and Westem Australia. Because of the damage they cause to the fruit industry it is illegal to bring codling moth or Infested fruit into the state. They are "declared" by the Agriculture Protection Board. WA fruit growers have a tremendous advantage over other states because we can market low-pesticide, pest-free fruit. Why codling moth matters to you Codling moth is the most damaging insect pest of apples and pears. It can tunnel Into every single fruit on a tree. Damaged fruit may fall prematurely and no one wants to buy fruit with tunnels filled with larval excreta (frass). To prevent codling moth infestation growers have to spray up to 10 times each season with broad spectrum insecticides. These chemicals also kill beneficial insects, increase the amount of pesticide in the environment and cost growers dearly in both time and money. Codling moths prefer apples, but they will also attack pears, nashi, quince and crab apples (the pome fruits). They have attacked stone fruit overseas, but this has not yet been seen in Australia. On rare occasions they attack walnuts. What you should look for Adult moths are dull brown and about one cm long. They have a dark patch with metallic bronze markings at the end of each wing. You will rarely see any eggs. They are small (one mm), round and flattened. Larvae are less than two mm long when hatched, but reach up to two cm long when full grown. You can tell if fruit contain codling moth larvae by the abundant frass seen on the outside of the fruit. Cocoons are tough, white and stick firnily to the bark of the fruit tree. Pupae are dark, orange-brown and about one cm long. Why codling moth might succeed in WA Codling moth has three generations every year in WA. Generation 1: The larvae over-winter cocooned in cracks and under bark of infested trees. They pupate in early spring; emerge in October and November, soon mate and lay eggs on the surface of small developing fruit. The larvae hatch out and burrow into the fruit to reach the core where they eat the seeds. As the fruit develops so does the moth larvae. By December the first lan/ae have reached full size. They drop to the ground on a silken thread and crawl to the trunk. There they spin a cocoon and pupate under the bark. Generation 2: Moths emerge in December and January, mate and lay eggs on fruit. The larvae bore into the fruit, feed, leave, and pupate in the same way. Generation 3: Moths emerge in February and March, repeating the process yet again. However the resulting larvae spin cocoons and over-winter in them. They pupate the following spring. Early warnings Codling moths fly at dusk, but only from October to April. Male moths are attracted to females by a strong scent (pheromone). Traps give early warning of the presence of codling moth. They attract moths by synthetic pheromones, released from tiny rubber plugs. They catch moths on a sticky inside surface. Traps are effective in catching male codling moths from October to April. Site them in apple or pear orchards and replace them every month. Pheromone traps give early warning of codling moth infestations and allow us to carry out cost-effective eradication programs. What you can do about it If you find an apple or other pome fruit with a frass-filled tunnel reaching into the core, take it to the nearest Agriculture Protection Board or Department of Agriculture office for identification. Other pests, such as the light brown apple moth and fruit fly can cause damage similar to codling moth, but these insects do not tunnel to the core and eat the seeds. Most important, do not bring fruit into WA from the eastem states or from overseas. Declare any you have with you at the checkpoint or dispose of it at the airport. Where to find out more For more information ring the Codling Moth Operations Centre at Bridgetown (097) or the Agriculture Protection Board, Baron-Hay Court, South Perth Telephone (09) Text by Bill Woods, WA Department of Agriculture, entomologist

20 THE DLINCT moth story The serious apple pest, Codling moth was discovered at Bridgetown in January 1993 and at Upper Kalgan in April The discovery of this pest resulted in a three season eradication campaign to save Western Australia's $35 million apple industry. Codling moth was beaten by a strategy of minimum reliance on pesticide and with the support of the local community. WHAT DOES IT MEAN l l POME Fruit Family - Apples, pears, quinces, crabapples, nashi fruit. g PHEROIUIONE - a natural scent which is placed in traps to attract male moths. ll FRASS - Brown saw dust like excreta produced by the Codling moth caterpillar. Western Australia is fortunate to be free of the world's most serious apple pest Codling moth, (Cydia pomonella). and WA are the only apple growing regions without estabushed populations of this insect. The Moth Codling moth is only about 1 cm long. It is a grey/brown colour and it is distinguished by a copper coloured band near the tip of each forewing. Codling moths prefer apples, but will attack other pome fruit. The Problem Codling moths lay eggs on or near fruit. Later larvae emerge and tunnel into the fruit to reach the core, enlarging the Spraying with DDT (1956) HISTORY OF THE MOTH PROBLEM An ovenvintering Codling Moth larvae in its cocoon under the bark of a tree Japan tunnel as they go and expeuing frass through the entry point. When the larva reaches the core of the fruit it feeds on the seeds. After maturing, it makes a new tunnel to the outside using another path. A fruit infested with the CodUng moth lama is very unpleasant to eat. To control the moth once estabhshed, it is necessary to spray trees up to 10 times each season with pesticides. This is what we are trying to avoid in Western Austraha. There have been 17 outbreaks of Codling moth in Western Australia, Apples showing larvae and frass since All were eradicated. The previous largest outbreak was detected at Bridgetown in February 1956 and involved eight orchards including one which was severely infested. Eradication was achieved by 1959 using pesticides such as DDT and lead arsenate. During this time, some 113 orchards occupying 600 ha were quarantined.

21 ^^ " ^.VtijftSCiV-^K,:" PREVIOUS OUTBREAKS The Bridgetown and Kalgan areas were important orcharding areas before about Decline of the industry saw many orchards subdivided into smaller hobby farm type blocks. Many fruit trees were left on these properties and not cared for as well as they may have been in a productive orchard. This resulted in many old neglected trees with the potential to harbour any number of pests. 995 BRIDGETOWN AND K,4LGAN The latest outbreak of Codling moth probably occurred because an infested fruit was brought into Western Australia, and thrown away when a Codling moth grub emerged. Although our State has stringent quarantine laws, which ban the introduction of pome fruit into Western Austraha, sometimes fruit still gets through. With the increased number of tourists visiting WA, this risk is greater every year. The chance discovery of a larva in an apple at Bridgetown on Janviary 31, 1993, and in Kalgan on April 14, 1993, began an eradication program which lasted three seasons and cost over.$2 million. The program was run jointly with Agriculture Protection Board, Department of Agriculture and WA Quarantine and Inspection Service staff. The eradication plan was developed together with Graham Thwaite, the foremost Codling moth expert in Australia, from NSW Agriculture. Because of the spread of the infestation in Bridgetown and Kalgan, the moth may have been in the areas for at least 2 years. In one orchard in Bridgetown over 70% of fruit was infested. Fortunately in Kalgan, the infestation was on an isolated property and the infestation did not spread from there. ^ ^ ^ * * 1 - PROPERTY UNDER QUARANTINE A _ NO UNAUTHORISED ENTRY '] CODLING MOTH INFESTATION NO FRUII IS TO BE BEMOVED FBOM THIS PROPERTY WITHOUT PEBMISSiON OF AN INSPtCIOR PENALTY FOR NON-COMPLIANCE UPTOS10000 Ph M^ :' "%/ Y X^" Under the Plant Diseases Act, properties infested with Codling moth had to display a quarantine sign

22 To help protect our Codling moth FREE State, DO : i ^ Check your own fruit for signs of Codling moth; look for holes in the skin with frass hanging out. D^ Declare any fruit at the border, if you have visited the eastern states. C^ Under no circumstances bring any fruit into Western Australia. C^ Tell your friends about Codling moth and why we need to keep the pest out of our State. [ THE STORY IN NUMBERS ^ NUMBER OF JAN 1993/ JULY 1993 JULY 1993/ JULY 1994 MOTHS TRAPPED STAFF EMPLOYED TOTAL PROPERTIES Commercial Orchards JULY 1994/ JULY 1995 FRUIT INSPECTED 56,000 51,000 35,000 FRUIT TREES STRIPPED 32,000 11,000 8,000 FRUIT TREES REMOVED 29, C^ Bring in any fruit that has some thing inside it that you are not sure about, to any Agriculture office for identification. MONEY SPENT (does not include permanent staff salary costs). $900,000 $400,000 $323,000 WHAT IS A CODLING MOTH TRAf Codling moth traps monitor tlie level of insect activity in an area. oo HUW UOES ACODLING MOTH TRAP W0Ri^9 The trap has a sticky base on which a pheromone plug is placed. The female pheromone attracts the male moth, which gets stuck on the sticky base. DOES ATRAP ERADICATE CODLING MOTH'' No, a trap only tells us there are certain insects in the area. It only traps the male moth, the female moth may well lay many eggs to continue the lifecycle. For further information contact your local Agriculture office. Other measures to interupt the lifecycle are therefore required. AGRICULTURE PROTECnON ^ak\ BOARD OF WA DEPARTMENT Of AGRICULTURE WESTERN AUSTRALIA

23 WHY it is important to keep Codling moth out of Western Australia! ^ COST - Our apples and pears are cheaper because less sprays need to be applied. About 10 sprays would be required a season if Codling moth became established at a cost of over $5 millior^ to the industry, ^ MARKET ADVANTAGE - Countries all over the world prefer produce grown with few pesticides. Our apples and pears can be marketed using [he "green and clean'' image. > LIFESTYLE - We are fortunate to be able to pick an unsprayed apple from a tree, and enjoy the apple without a Codling moth grub inside. roi^g 66 President Bridgetown Fruit Growers Association During the campaign individuals suffered loss of income, precious trees and some privacy for the good of the WA pome fruit industry as a whole. But Bridgetown has also benefited by the removal of many derelict trees. ACPOWLEDGEMENTS Program l^anager Greg Power Program Entomologist Bill Woods Editor Diny Monaghan Graphic Designer Jookie Wong Photograpiis Robyn Knox, Frank Smith, Bill Woods and Col Bower ) > ^