Apple Pest Management in the West: Strategies to Deal with Inevitable Change

Apple Pest Management in the West: Strategies to Deal with Inevitable Change

Background 1960s: Resistance to chlorinated hydrocarbons in many pests Spider mites elevated to key pest status - resistance to miticides and no biological control Stan Hoyt develops integrated mite management - selective insecticides plus biological control of mites. 1970s: Stable chemical control of key pest (codling moth) with organophosphate insecticides Resistance starts to develop in secondary pests - leafhoppers Integrated mite management remains stable

Background 1980s: Resistance to organophosphate insecticides develops in more pests, e.g. leafrollers Leafminer outbreaks (insecticide resistance induced) occur and spread, biological control established in majority of orchards Number of insecticide applications to control codling moth increases Integrated mite management effective but less stable, more specific miticides used

Background Early 1990s: Resistance to organophosphate insecticides develops in the key pest, codling moth Public opinion about safe food, environmental quality and farm worker safety drive regulatory debate Food Quality Control Act of 1996 changes the way pesticides are reviewed and registered Mating disruption shows promise for managing codling moth Growers use biological insecticides (Bacillus thuringiensis) to soften control programs for leafrollers and to conserve leafminer natural enemies

Codling moth is the KEY PEST in pome fruit production in Washington. It represents the greatest potential for crop loss and more pesticides are specifically used to control this pest than any other. Percent Codling Moth Damage 100 90 80 70 60 50 40 30 20 10 0 Harvest 1994 1st gen. 1995 Harvest 1995 1st gen. 1996 Harvest 1996 Codling moth well adapted to hot-dry climate. Capable of rapid population increase causing severe crop loss. WSU-TFREC JFB, 2000

Primary insecticides used to control the codling moth in Washington from 1989 through 1997. Codling moth Key Pest Ave. No. of applic./a (% area) Insecticides 1989 1991 1993 1995 1997 azinphosmethyl 2.9(98) phosmet 2.4( 4) methyl parathion 1.1(17) 2.8(90) 2.1( 9) 1.5(28) 3.3(81) 1.1(19) 1.2(24) 3.3(94) 2.4( 2) 1.2(19) 2.9(91) 1.2(<1) 2.0(33) WSU-TFREC JFB,1999

Male Moth Orientation to Pheromone and Mate Location Pheromone plume Female moth Male moth

PHEROMONE DISPENSER MATING DISRUPTION MECHANISM False Trial Following Female moth Male moth

Preliminary research codling moth mating disruption Percent fruit injury - ALL Sites Percent fruit injury - Sites 1,2,4, and 6 0.4 0.3 1.6 1.2 0.8 0.4 Conventional Mating disruption 0.2 0.1 0.0 1991 1992 1993 Percent fruit injury - Sites 3 and 5 5 4 3 2 0.0 1991 1992 1993 1 0 1991 1992 1993

Apple Production Without use of Neuroactive Insecticides Six sites Jointly funded by SARE and WSTFRC Direct comparison of the economics and ecology of Delicious apple orchards managed without using neuroactive insecticides or managed conventionally

Apple Production Without the Input of Neuroactive Insecticides Six sites Paired comparison NNI CONV Washington Tree Fruit Research Commission provided crop loss insurance, $50,000/year to reduce grower risk 20 acre apple orchards divided into two 10 acre blocks

Example of Site Layout Site: W2 Twin WW Orondo, WA NNI CONV 10 acres

Pest Control Tools Pest Codling moth Leafrollers Aphids Leafhopper Leafminer Campylomma Mites, scale CONV Guthion Lorsban, Bt Provado Sevin Vydate Lorsban oil/lorsban NNI Isomate-C+, oil, Confirm Bt, Confirm M-Pede, Neemix insecticidal soap, Vaporgard, oil, Neemix oil Neemix oil

MONITORING ACTIVITIES Pest, natural enemies Codling moth Leafrollers, parasites Aphids, predators Leafhopper, parasites Leafminer, parasites Campylomma Mites, predators Pesticide use Pest control programs Monitoring methods or records Pheromone traps, fruit damage Pheromone traps, shoots, fruit damage Visual inspection of shoots Nymphs on leaves, adults on traps, eggs Mines in leaves, parasite in mines Beating trays counts Leaf brushing Spray records Cost of products and applications

Apple Production Without the Input of Neuroactive Insecticides % codling moth injury 3.0 2.5 2.0 Conventional NNI 1.5 1.0 0.5 0.0 1995 1996 1997

Apple Production Without the Input of Neuroactive Insecticides % Leafroller injury 4.0 3.5 3.0 Conventional NNI 2.5 2.0 1.5 1.0 0.5 0.0 1995 1996 1997

Apple Production Without the Input of Neuroactive Insecticides Leafhopper nymphs per leaf 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0.00 1995 1996 1997 Leafhopper nymphs per leaf 3.0 2.5 2.0 1.5 1.0 0.5 0.0 1995 1996 1997 Conventional NNI Leafhopper densities in the CONV orchards was suppressed by Sevin (carbaryl) when used as a fruit thinner. In the second generation leafhopper densities were about the same in CONV and NNI orchards. The dramatic decline in leafhopper densities in 1997 is attributed in part to activities of the egg parasite, Anagrus sp.

Apple Production Without the Input of Neuroactive Insecticides 3.0 2.5 2.0 1.5 1.0 0.5 0.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0.0 Leafminer density (mines/leaf) 2nd generation 1995 1996 1997 3rd generation 1995 1996 1997 Conventional NNI The densities of leafminer was generally higher in CONV than NNI orchards. Some CONV orchards applied specific controls for leafminers. In all NNI orchards treatment thresholds were not exceeded. In 2 CONV orchards insecticides were needed in 2 years to suppress leafminer below damage levels.

Apple Production Without the Input of Neuroactive Insecticides 70 60 50 40 30 20 10 0 90 80 70 60 50 40 30 20 10 0 % parasitism of WTLM 1995 1996 1997 3rd generation 2nd generation 1995 1996 1997 Conventional NNI Parasitism of leafminer by Pnigalio flavipes was generally higher in the NNI orchards. Pnigalio flavipes is known to be resistant to azinphosmethyl (Guthion) so was not suppressed by CONV pest control programs.

Apple Production Without the Input of Neuroactive Insecticides 300 250 200 Cost ($) per acre of pest control tactics Conventional NNI 150 100 50 0 1996 1997

Apple Production Without the Input of Neuroactive Insecticides 1997 1996 1995 Major pests 0 2 4 6 8 Conventional NNI The number of insect control tactics applied against major pests was about the same in 1995 and 1996 but declined in the NNI program in 1997. 1997 1996 1995 Minor pests 0 2 4 6 8 Ave. number of applications per acre The number of insect control tactics (insecticides) applied against minor pests in the CONV program remained constant but was low and declined in the NNI program plots.

225 200 175 150 125 100 75 50 25 0 Abundance of six invertebrate groups collected in pit fall traps # of individuals NNI CONV Earwigs Carabidae Harvestment Spiders Collembola Snails/ slugs

Codling Moth Areawide Management in the Western United States Codling moth control using pheromones Reduction of broad-spectrum insecticides Intensive monitoring of other pests Enhanced biological control of secondary pest

Codling Moth Mating Disruption in Washington State Number of acres treated 90000 80000 70000 60000 50000 40000 30000 20000 10000 0 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000

Areawide Codling Moth Management Sites Lake Osoyoos; 160 hectares - Apple Howard Flat; 440 hectares - Apple Parker Heights; 180 hectares - Apple/Pear Carpenter Hill; 160 hectares - Pear Randall Island; 300 hectares - Pear WSU-TFREC JFB,1999 Total project = 1240 hectares

Howard Flat CAMP Site - Lake Chelan Howard Flat CAMP site

Howard Flat CAMP site (Codling moth Areawide Management Project) Geographically isolated Primarily apple production 36 growers; 16 fieldmen 4 packing houses 1,200 acres total Management Board Science Advisory Committee USDA funding $50 per acre project subsidy WSU-TFREC JFB, 2000

Howard Flat CAMP Site Chelan, Washington 1994 Pre-program data; 1995-1998 Codling Moth Areawide Management Project results. Average number of moths per trap Average percent fruit injury Average number of sprays per acre Moths per trap per year 35 30 25 20 15 10 5 0 No. traps: 95-97 = 450, 98 = 326 1994 1995 1996 1997 1998 Percent fruit injury at harvest 0.8 0.7 0.8 0.6 0.5 0.4 0.55 0.3 0.2 0.2 0.1 0 1994 1995 Average number sprays/acre 1996 1997 1998 3.0 2.5 2.0 1.5 1.0 0.5 0.0 1994 1995 1996 1997 1998

Fruit damage by codling moth Howard Flat: 1995-1996 1995 0.55% 0.20% 2-5% 1-1.9% 0.5-0.9% 0.25-0.49% 0.25-0.01% 0.0%

Howard Flat CAMP Site Chelan, Washington 1994 Pre-program data; 1995-1998 Codling Moth Areawide Management Project results. Average number of moths per trap Average percent fruit injury Average number of sprays per acre Moths per trap per year 35 30 25 20 15 10 5 0 No. traps: 95-97 = 450, 98 = 326 1994 1995 1996 1997 1998 Percent fruit injury at harvest 0.8 0.7 0.8 0.6 0.5 0.4 0.55 0.3 0.2 0.2 0.1 0.01 0.02 0 1994 1995 Average number sprays/acre 1996 1997 1998 3.0 2.5 2.0 1.5 1.0 0.5 0.0 1994 1995 1996 1997 1998

Fruit damage by codling moth Howard Flat: 1997-1998 0.01% 0.02% 2-5% 1-1.9% 0.5-0.9% 0.25-0.49% 0.25-0.01% 0.0%

Areawide Codling Moth Management Program Enhance activities of natural enemies on secondary pests by reducing the use of broadspectrum insecticides. 1996 1997 1998 1996 1997 1998 Example #1 Leafhopper Overwintering Eggs 41.4 13.7 20.9 9.6 44.3 20.3 0 20 40 60 80 100 0 20 40 60 80 OW WALH eggs % parasitized % parasitized a CONV b MD a b a b

Areawide Codling Moth Management Program Enhance activities of natural enemies on secondary pests by reducing the use of broadspectrum insecticides. 1996 1997 1998 1996 1997 1998 0.0 0.11 0.03 Example #2 Predatory Mites - June 0.21 0.20 0.23 CONV MD 0.2 0.4 Predatory mites/leaf (June) 0.47 0.6 0.0 0.2 0.4 0.6 Mites/leaf a a b a b a

Codling Moth Mating Disruption in Washington State Number of acres treated 90000 % acres treated in WA 45% 80000 70000 60000 30% 50000 40000 30000 20000 10000 0 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000

Future? 2000s: FQPA will eliminate or severely limit the use of traditional chemical control tools in apple pest management New insecticides with novel modes of action will be registered for use on apple Mating disruption continue to grow as a pivotal tactic in apple pest management Biological control of many pests will improve through use of selective insecticides and habitat management Global competition for apple markets will continue to increase The structure of Washington s fruit industry will change: consolidation, new varieties, stable acreage Water will become a limited resource

Key Pest Leafroller Selective chemicals IGR, Bt Mating Disruption Leafminer Oil Leafhopper Soap, oil Organophosphate Carbamate Insecticides Aphids Provado WSU-TFREC JFB/1996