Chapter 24

Greenhouse Pesticides

(draft book excerpts)

Greenhouse environments provide a variety of benefits for plant production; however, many greenhouses favor pest development as well. The warm, humid conditions and abundant food are ideal for pest build up. Natural enemies that serve to keep some pests under control in the field are absent in the greenhouse. For these reasons, pest problems often develop more rapidly and are more severe in enclosed systems, which require the use of pesticides. Pesticides include any substances used either to directly control pest populations or to prevent or reduce damage to the crops in the greenhouse. There are many pesticides available for use in greenhouses, all of which control specific pest and disease problems in growing crops. Although many pesticides are designed to kill pests, some may only inhibit their growth, or simply attract or repel them. There are several approaches to the classification of pesticide types. Pesticides are often referred to according to the type of pest they control. For example, insecticides are pesticides that target insects, fungicides target fungal diseases, and herbicides target weeds. Pesticides can also be organized by their chemical class. There are many classes of synthetic pesticides. The main classes consist of organochlorines, organophosphates, carbamates, and pyrethroids. We define conventional or chemical pesticides as those having a broad spectrum of activity and being more detrimental to natural enemies. Another way of classifying pesticides is how or when they work—contact, systemic, preemergent, postemergent, selective, and non-selective (or broad-spectrum). Pesticides can be grouped according to their mode of action or the way a pesticide controls the target pest. This is also referred to the primary site of action. For example, one insecticide may affect an insect’s nerves while another may affect moulting. Pesticides can also be classified as biorationals— pesticides that are more selective because they are most effective against pests with certain feeding habits, at certain life stages, or within certain taxonomic groups. These are also known as “least toxic” pesticides. Because the biorationals are generally less toxic and more selective, they are generally less harmful to natural enemies and the environment. A similar term used is “biopesticides.”

Click on the following topics for more information on greenhouse pesticides.

Topics Within This Chapter:

  • Insecticides
  • Methods of Application
  • Contact Insecticides
  • Systemic Insecticides
  • Mode of Action
  • Breadth of Activity
  • Broad Spectrum
  • Target-Specific
  • Fungicides
  • Mobility in the Plant
  • Contact Fungicides
  • Systemic Fungicides
  • Mode of Action
  • Target Site
  • Single-Site
  • Multi-Site
  • Role in Protection
  • Protectants
  • Penetrants
  • Herbicides
  • Methods of Application
  • Soil-Applied Herbicides
  • Foliar-Applied Herbicides
  • Time of Application
  • Chemical Management Strategies
  • Downy Mildew
  • Pre-Emergence
  • Post-Emergence
  • Mode of Action
  • Mobility in the Plant
  • Contact Herbicides
  • Systemic Herbicides
  • Target Site
  • Selective Herbicides
  • Non-selective Herbicides
  • Chemical Pesticides
  • Types of Chemical Pesticides
  • Biorationals
  • Biopesticides
  • Microbials
  • Bacteria
  • Fungi
  • Viruses
  • Botanicals
  • Spray Oils
  • Insecticidal Soaps
  • Minerals
  • Insect Pheromones
  • Insect Growth Regulators
  • Pesticide Formulations
  • Formulation Process
  • Sorption
  • Solution
  • Suspension
  • Emulsion
  • Liquid Formulations
  • Liquid Flowables (L or F)
  • Emulsifiable Concentrate (EC or E)
  • Solutions (S)
  • Dry or Solid Formulations
  • Dusts (D)
  • Granules (G)
  • Pellets (P)
  • Wettable Powders (WP)
  • Water-dispersible Granules (WDG) or Dry Flowables (DF)
  • Soluble Powder (SP or WSP)
  • Other Formulationss
  • Fumigants
  • Microencapsulated Pesticides (M)
  • Water-soluble Packets (WSB or WSP)
  • Spray Adjuvants
  • Types of Adjuvants
  • Buffers or pH Modifiers
  • Conditioning Agents
  • Compatibility Agents
  • Defoaming Agents
  • Drift Control Additives
  • Emulsifiers
  • Extenders
  • Safeners
  • Stickers
  • Surfactants
  • Thickeners
  • Pre-Mix versus Tank-Mix Pesticides
  • Pre-mixed Pesticides
  • Tank-mixed Pesticides
  • Compatibility of Pesticides
  • Physical Compatibility Test
  • Federal Law
  • Pesticide Product Labels
  • Material Safety Data Sheet
  • Parts of Pesticide Label
  • Identifying Information
  • Statement of Use Classification
  • Signal Words and Symbol
  • Hazards to Humans and Domestic Animals
  • Environmental Hazards
  • Directions for Use
  • Managing Pesticide Resistance
  • General Guidelines in Managing Pesticide Resistance
  • Adopt an Integrated Pest Management Plan
  • Consider Alternative (non-chemical) Pest Management Measures
  • Avoid Persistent Chemicals
  • Apply Only Recommended Pesticide Application Rates
  • Optimal Spray Coverage
  • Pesticide Mixtures
  • Use Different Modes of Action
  • Use Long-Term Rotations
  • Pesticide Laws and Regulations
  • Federal
  • Pesticide Registration
  • Licenses
  • Record Keeping
  • States
  • References