Avoiding Pesticide Resistance

Transcription

1 Avoiding Pesticide Resistance Trent Taysom & Jeff Miller Assistance from Dr. Pam Hutchinson, Dr. Don Morishita, and Dr. Erik Wenninger, University of Idaho 1

2 What is Pesticide Resistance? The heritable change in the sensitivity of a pest population that is reflected in the repeated failure of a product to achieve the expected level of control when used according to label recommendation for that pest species. (IRAC, emphasis added) Not all pesticide failure is due to resistance 2

3 How do I know if I have resistance, or ineffective application? Same weed species healthy and dying in same area. Pests controlled in the past are not controlled now. Submit a sample for analysis. Example 1 Herbicide Resistance Photos by Dr. Joel Felix, Oregen State University 3

4 Why should we care? Resistance causes changes in management practices: Increased cost of pest management Reduction of effective options Yield and income loss Very few new pesticides are being developed. Need to maintain those that are currently available. Examples of Pesticides Acaricide Mites, ticks, spiders Molluscicide Snails and slugs Antimicrobial Attractant Bacteria, viruses, other microbes Attracts pests for killing or monitoring Nematicide Piscicide Nematodes Fish Avicide Birds Predacide Vertebrate predators Fungicide Fungi Repellant Repels pests Herbicide Weeds Rodenticide Rodents Insecticide Insects Synergist Improves performance of other products 4

5 Resources for Managing Pesticide Resistance Pesticide Group Numbers Members of same group target pests in a similar manner. Resistance to one group member may confer resistance to other group members. Effective tool for helping rotate active ingredients. 5

6 So how does pesticide resistance develop? Development of Pesticide Resistance Scenario 1 1. Mixed pest population (largely susceptible to pesticide ). 6

7 Development of Pesticide Resistance Scenario 2 1b. Mixed pest population (largely susceptible to pesticide ). Example 1 Insecticide Resistance 7

8 Did you know... WWI French drafted plans to release CPB on the Germans. WWII Germany attempted to develop a CPB army. Germany claimed US/Britain was doing the same. The American beetle will destroy our crops and threaten your livelihood! Saboteurs in American Services at work! Fight for peace! By Bundesarchiv, Bild / Biscan / CC-BY-SA 3.0, CC BY-SA 3.0 de, Cumulative Number of Active Ingredients Resistance in CPB Alyokin et al., AJPR 85:

9 Chemical Groups with CPB Resistance Carbamates Organophosphates Organochlorines Cyclodiene organochlorines Organotins Inorganics Pyrethroids Isoflavenes Neonicotinoids Avermectins Nereistoxin analogues Spinosyns Bt proteins Alyokin et al., AJPR 85: Mechanisms of Resistance Metabolism (breakdown) of insecticides Target site insensitivity Reduced insecticide absorption/increased excretion 9

10 Example 2 Fungicide Resistance Example 2 Fungicide Resistance Luna Tranquility, 11 fl oz/acre Endura, 5.5 oz/acre Early Blight/Brown Leaf Spot in Potato 10

11 Premium Early Blight Fungicides QoI Fungicides Group 11 Quadris Headline Evito Gem Tanos Reason Quadris Opti (also group M5) Quadris Top (also group 3) Organotin Group 30 Super Tin Stronger on late blight Triazoles Group 3 Revus Top (also group 40) Quadris Top (also group 11) Quash Carboxamides Group 7 Endura Luna Tranquility (also group 9) Vertisan Priaxor Pyrimethanil Group 9 Scala Luna Tranquility (also group 7) Strong on gray mold Strong against white mold Percent EB Control with QoI Fungicides (Group 11) Miller Research Trials Quadris Headline Tanos Reason

12 MOA Target Site Group Name Chemical Group Common Names FRAC Code Complex III SDHI (succinate dehydrogenase inhibitors) Pyradinyl-ethyl-benzamides Pyrazole-carboxamides Fluopyram Benzovindiflupyr Fluxapyroxad Penflufen Penthiopyrad Sedaxane 7 Pyridine-carboxamides Boscalid Respiration QoI fungicides (Quinone outside inhibitors) Methoxy-acralates Methoxy-carbamates Azoxystrobin Picoxystrobin Pyraclostrobin Complex II Oximino acetates Oxazolidine-diones Trifloxystrobin Famoxadone 11 Dihydro-dioxazines Fluoxastrobin Imidazolinones Fenamidone MOA Target Site Group Name Chemical Group Common Names FRAC Code Complex III SDHI (succinate dehydrogenase inhibitors) Pyradinyl-ethyl-benzamides Pyrazole-carboxamides Luna Tranquility Elatus Priaxor Emesto Vertisan Fluopyram Benzovindiflupyr Fluxapyroxad Penflufen Penthiopyrad Sedaxane 7 Pyridine-carboxamides Endura Boscalid Respiration QoI fungicides (Quinone outside inhibitors) Methoxy-acralates Methoxy-carbamates Quadris, Aproach Headline Azoxystrobin Picoxystrobin Pyraclostrobin Complex II Oximino acetates Oxazolidine-diones Gem Tanos Trifloxystrobin Famoxadone 11 Dihydro-dioxazines Evito Fluoxastrobin Imidazolinones Reason Fenamidone 12

13 Pesticide Resistance Influenced by: Nature of pesticide (protectant vs. systemic) Pesticide use patterns Biology of pathogen/pest Cross resistance = Development of resistance to one chemical also confers resistance to another chemical. Protectant vs. Systemic Fungicides Protectant Attack multiple sites in pest Protect where applied Not as effective as systemics Examples Chlorothalonil EBDC products Omega Super Tin Systemic Target one or few sites in pest Can move within the plant Highly effective Examples Quadris, Headline, Tanos Endura, Luna Tranquility Curzate, Previcur, Forum Ridomil Gold 13

14 How do you avoid pesticide resistance? 1. Use an integrated pest management approach. Use all management tools available. Do not rely on a single approach. Use cultural practices whenever possible. Reduce use of the pesticide whenever possible. 2. Use scouting and field history to determine pesticide need. 3. Use multiple modes of action. Rotation of chemistry Tank-mix 4. Apply at the recommended rate and timing. Sub-lethal doses can favor faster selection of resistance. We can t rely on new pesticide development. Last new herbicide mode of action was released 20 years ago. No products with new mechanisms in advanced development Most new fungicides are in existing fungicide classes. 14

15 Take Home Message Resistance management should be a high priority for you. Don t rely on a single mode of action. Rotate and tank-mix chemistries. 15