Purchasing a Pesticide: Pesticide Action, Formulations, and Adjuvants Montana State University Pesticide Safety Education Program 2008

What is a formulation? How a pesticide is packaged. Contains: – –Active Ingredient – –Inert Ingredient

Active Ingredients Has the pesticidal effect Its on the label Properties of the a.i. influence the Formulation A.I. derived from: – –Plants – –Minerals – –Microbes. Nicotine, Pyrethrum, and Rotenone Copper, and Sulfur Bacillus thuringiensis, Metarhizium anisopliae

Inert Ingredients “Inactive” ingredients mixed with a.i. To make formulation easier to handle or store. Toxic or non-toxic

Can you get the same reaction from the same active ingredients regardless of inert ingredients? NO, Inert Ingredients are often patented and are only known to the company. Many times this is the difference between a product working effectively and not at all. BANDED, SEED, FOLIAR applications all different yet the same!

Types of Formulations Liquid (Wet) – –Mixed with water / oils / diesel fuel / kerosene – –More easily absorbed Dry – –More easily inhaled

Liquid Formulations (Wet) EC –emulsifiable concentrate S – soluble Flowables ULV – ultra low volume (approach 100% active ingredient)

Soluble Advantage: – –☺ Will not separate or settle out when mixed with water. – –☺ Not as harmful to non-target plants and animals Disadvantage: – –Not many disadvantages. – –Readily absorbs into skin

Emulsified Concentrates (1 or more petroleum based solvents) ADVANTAGES – –☺ Little agitation required. Won’t settle out when equipment is turned off. Does not plug equipment – –☺ Relatively non-abrasive. – –☺ Easy to handle, store and transport DISADVANTAGES – – Because of the solvents and emulsifiers, EC’s are a hazard to non-target plants and animals. Easily absorbed through skin of plants and humans. – – Solvents may cause rubber or plastic hoses & gaskets to deteriorate. - May cause pitting of painted finishes, and may be corrosive

Flowable ADVANTAGES ☺ Easy to handle and apply ☺ Seldom clogs nozzles. Finer ground carrier. DISADVANTAGES May leave visible residue. Requires agitation

Dry Formulations WP – Wettable powder F or DF – Dry Flowable WDG – Water Dispersible Granule D -Dust Baits  P or G – Pellets or Granules

Wettable Powders ADVANTAGES – –☺ Easy to store & transport. Smaller packaging. Won’t freeze. – –☺ Less inert ingredients in formulation. – –☺ Lower toxicity to plants than liquid formulations. – –The inert ingredients, clay or talc, are generally harmless to plants DISADVANTAGES – –Inhalation hazard when pouring and mixing. It’s dry! – – Needs vigorous & constant agitation in the spray tank. – – Abrasive to many pumps and nozzles.

Granules or Pellets ADVANTAGES – –☺ Ready to Use (RTU); no mixing – –☺ Low drift hazard as particles settle quickly. – –☺ In most cases, don’t need to mix with water first. DISADVANTAGES – –May need to be incorporated into the soil. – –Dust from application equipment might present hazard to applicator. – –May need to be activated by moisture – –Hazardous to some non-targets (birds) – –Easy to over apply

Effects of Different Formulations FormulationHazardsPhytoxEquipmentAgitate M or ME Dermal Safe okYes G or P Inhale Safe NA NA D Inhale Safe NA NA S Dermal Safe Non-abrasive No F or FL Dermal Maybe abrasive Yes EC Dermal Maybe Seals, gaskets No WP Inhale Safe abrasive Yes

Adjuvants Additives that are added to a spray solution in order to enhance or modify the performance of the spray mixture. #1 - Surfactants/wetting agents #2 - Oils #3 - Fertilizers #4 - Utility

Surfactants A broad category of adjuvants that facilitate and enhance the absorbing, emulsifying, dispersing, spreading, sticking, wetting and penetrating properties of pesticides. Some pesticides like Roundup Pro already have surfactants added. (14.5 %)

Why Surfactants Because of the high surface tension of water, spray mixture droplets maintain their roundness and can sit on the leaf hairs or leaf surface without much of the mixture actually contacting the leaf. Surfactants reduce angle and promote more absorption

Utility Acidifiers -neutralize alkaline solutions & lower pH. Buffering agents -stabilize the pH of spray solutions. Anti-foaming agents Compatibility agents Drift control agents Emulsification aids Suspension aids -added to a suspension in order to keep pesticide particles dispersed or to resuspend particles.

What formulation is this? FLOWABLE DERMAL ABSORPTION Examples: Bravo 720 F fungicide Furadan 4 F insecticide

Question #2 What formulation is this? Powdered Hand Soap Wettable Powder Easily Inhaled Examples: Sevin 50 W insecticide Kerb 50 W herbicide Sniper 50 W insecticide

Pesticide Properties Important to Know Prior to Purchase Formulation Adjuvants to use with this pesticide Other properties?

What to know when purchasing a Herbicide #1) Application Method –Foliar Applied Plant contact –Soil Applied Soil contact –Broadcast Entire area –Spot Specified area

What to know when purchasing a Herbicide #2) Application Timing –Preemergence Prior to seed germination –Postemergence After seed germination and active growth –Post-directed Directed to particular portion of plant once emerged and growing

Mode of Action Mechanism of Activity –Mode of action (MOA) How it kills

Herbicide Modes of Action Why is this important? 1. Plant Growth Regulation 2. Photosynthesis Inhibitors 3. Photosynthetic Pigment Inhibitors 4. Plant Growth Inhibitors 5. Amino Acid Synthesis Inhibition 6. Lipid Biosynthesis Inhibition 7. Cell Membrane Disruption 8. Unclassified Activity

Plant Growth Regulation Examples include: –2,4-D –Dicamba –Picloram –Clopyralid –Triclopyr

Plant Growth Regulation Mimics natural plant hormone – Auxins. Results in an imbalance of this growth regulating hormone. Cells of the leaf vein rapidly divide while cells between the veins do not. Cell division and respiration increase, while photosynthesis does not.

Common Leaf Symptoms from PGR Exposure normal cupped and blistered from PGR exposure

short internode accumulation In new growth Foliar PGR Application

How does this type of injury occur? Drift - both particle and vapor. Improper cleaning of equipment. Applying when air temperatures exceed those listed on the label. Exceeding the labeled rate.

Amino Acid Synthesis Inhibition Imidazolinones –Arsenal –Plateau –Sahara –Top Site Glyphosate –Roundup Sulfonylureas –Escort –Oust –Telar

Amino Acid Synthesis Inhibition Amino Acids = life!! Specific to plant AAs only Visual results are the result of secondary injury –the injury as the beginning of a chain of events that take place in the plant. –symptoms take time to develop – it is not an immediate process.

Amino Acid Synthesis Inhibition

May or may not have soil activity. Activity associated with a particular amino acid synthesis sequence. –Acetyl CoA Carboxylase (ACCase) - Select –Acetolacte Synthase (ALS) - Arsenal, Escort –EPSPase Inhibitor - Roundup Interference is translated to protein synthesis and inhibition of growth which takes time - slow acting.

Amino Acid Synthesis Inhibition What are you going to see visually? –Initially there will be a general yellowing of the treated plants. –After 5 to 10 days, chlorosis results in necrosis.

Plateau or Escort Injury Symptoms Stunting Chlorosis of youngest tissue

Glyphosate (Roundup) Drift chlorosis shortened internodes stem proliferation

How does this type of injury occur? Drift - application on a windy day. Movement of treated soil. Failure to apply the correct amount – the use rates are small and an error in measuring can make a large difference.

When purchasing pesticides know: Formulation Adjuvants How to use pesticide Pest Timing Mode of Action

Contact: Montana State University Pesticide Safety Education Program