- - AGRICULTURE CORE CURRICULUM - - (CLF7000) Advanced Core Cluster: PLANT AND SOIL SCIENCE (CLF7350) Unit Title: PLANT PATHOGENS AND PESTS ____________________________________________________________________________ (CLF7356) Topic: INSECTICIDE Time Taught in Year(s) CONTROL 1 hour 3 and 4 ____________________________________________________________________________ Topic Objectives: Upon completion of this lesson the student will be able to: Learning Outcome #: (Supplemental) - Understand that many factors go into making a control decision. If an isecticide is used, selection of the "insecticide" is based on several factors. Use of insecticides requires consideration for hazards to people wildlife, environment, and natural enemies. Special Materials and Equipment: References: Davidson and Lyon. (1989). INSECT PESTS. John Wiley and Sons. Davis, Hoyt, McMortry and Ali Niazee (eds). (1979). BIOLOGICAL CONTROL AND INSECT PEST MANAGEMENT. University of California Agriculture and Natural Resources Publication, 4096. Watson, Moore, and Ware. (1975). PRACTICAL INSECT. Pest Management. W.H. Freema. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ THIS TOPIC IS PROVIDED AS SUPPLEMENTAL INFORMATIN ONLY. IT GOES BEYOND THE SCOPE OF THIS CLUSTER. IT IS PROVIDED FOR ENRICHMENT PURPOSES AT THE INSTRUCTORS DISCRETION. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ TOPIC PRESENTATION: INTRODUCTION A. In the insect biology topic we discussed the various characteristics by which we can identify insects. B. Selecting the best control method(s) and, if needed, the correct pesticide requires proper identification. Identification which helps to determine when and where to focus control efforts. C. Different insects require different control methods. D. Also timing of your control method is extremely important. E. Our control measures can include one or more of the following methods: 1. Biological Control. 2. Cultural Control. 3. Physical or mechanical control. 4. Chemical control. NOTE: The above were discussed in our topic on Integrated Pest Management. CHEMICAL INSECT CONTROL A. An important distinction for insecticide control of insects attacking plants is the type of mouthparts that they have. Most modern insecticides kill by contact, therefore the most important consideration is getting the insecticide onto the body of the insect or surfaces the insect contacts. "Organic" materials, such as B.T., need to be ingested. 1. Chewing insects such as caterpillars and larvae and adults of other orders feed on flowers, foliage, fruit and shoots of plants. a. Poisonous sprays or dusts can be applied on any surface of the plant parts that they eat. b. When the insect consumes the plant part it also eats the poison, then dies. Systemic insecticides are applied to the soil or injected into trees, etc. to kill aphids and other sucking insects. 2. Sucking insects like aphids, leafhoppers, and scales probe into the interior of plants and suck out plant fluids. a. They can be killed by direct contact with an insecticide. b. Or they can be controlled by a insecticide that has been applied to the plant surface over which they move. B. Insecticides are classified into several categories. 1. They can be grouped according to the chemical composition of the insecticides. These include: a. Chlorinated hydrocarbons i.e., DDT, chlordane, methoxychlor (many of these have been banned because of their persistence in the enviornment, harmful to people and wildlife), b. Organophosphates (i.e. parathion, diazinon), c. Carbamates (carbaryl (sevin), aldicarb, methomyl), d. Natural organics (pyrethrin, rotenone, sulfur, sabadilla), e. Microbial pesticides (bacillus thuringiensis), f. Petroleum oils, and g. Insect Growth Regulators (I.G.R.s) 2. They can be classified according to the several ways they enter or affect insect bodies: a. Stomach toxicants, 1) Enter the insect body through the mouth and disgestive tract, from either being applied to plant surfaces eaten by insect or sap fed on by insect. b. Contact toxicants pass through the insect's outer body covering. c. Fumigants are volatile and enter the insects body as a gas through the respiratory system. d. Systemic toxicants are applied to plant parts, absorbed by the plant, then move through the plant to untreated parts (translocated). e. Suffocation action results from applying oils or soaps (soaps dissolve waxy coatings causing water loss - desication) which clog the breathing mechanism of the insect. C. Many factors are considered when making pesticide use decisions. 1. In residential and urban areas pests are usually controlled when people working or living in these areas can no longer tolerate them. a. Pesticides are chosen according to their safety, speed and effectiveness. b. In agriculture and other commercial business economics of pest control is also important. 2. For some pests (mostly insects, nematodes and mites) treatment thresholds have been established. a. These thresholds indicate what population levels can be tolerated without loss and at what level a pesticide loss will pay for itself. b. Such treatment thresholds must be flexible, allowing for changes in the market price for crops. 3. Decisions are based on extensive sampling, pest monitoring, and life history information. D. Selecting the right pesticide also requires additional thought and planning. 1. Often several pesticides can be used for control of any particular pest. 2. Information of pesticides for specific uses can be obtained from pesticide label books, farm advisors, agricultural commissioners, licensed pest control advisors, pesticides chemical handbooks, and from various agricultural colleges and university publications. IMPACT (Integrated Management of Production in Agriculture using Computer Technology) is an example of a computer network that is part of the university of California Statewide Integrated Pest Management Program. Pesticide use guidelines, toxicology information, and pest management techniques are available through this direct computer hook-up. 3. When selecting a pesticide the following listed factors also need to be considered: a. Cost of the pesticide, b. hazards to the user, c. plantback restrictions, d. persistence characteristics, e. ease of use and the pesticide's ability to combine with other materials, f. its effect on beneficial insects and natural enemies, and g. required reentry intervals and harvest limitations. E. Remember to apply pesticides: 1. to an identified pest at the susceptible life stage; 2. only when necessary based on monitoring, thresholds, crop stage, etc; 3. where they are needed; 4. in recommended amounts; 5. according to label directions; and 6. use pesticides along with other methods of control. F. Of special concern is the possible damage to beneficial insects when we are controlling problem pests. 1. One third of our agricultural crops require pollination. 2. Bees and other pollinating insects pollinate over $300 million worth of crops in California annually. 3. Under California law beekeepers can request notification of intended pesticide usages so they can move their bees or protect them in some other way. a. The applicator is required to inform the beekeeper of his planned application. b. He must inform the beekeeper of: 1) the time and place of application, 2) crop to be treated, 3) acreage to be treated, and 4) the type and amount of pesticide to be applied. c. Bees are important and much more damage is done to natural enemies through indescriminate use of insecticides. 7/24/90 gfv/sg #%&C