With a broad range of surfactants from a number of manufacturers to choose from, rural retailers and agronomists can be forgiven for becoming confused about which product is the best one to buy, and which one to recommend.
So to help, here is a guide:
Wetting Agents i.e. 1000g/L and 600g/L:
These simply act to break surface tension, and act as a simple non-ionic surfactant and spreader. They are relatively non persistant, and will wash off with rainfall, needing to completely dry on the crop surface for best sticking. Old technology products are based on alcohol alkoxylates (BS1000®, Agral®). New up-to-date products such as Econ-A-Wett® 1000 are based on nonyl phenols and alcohol ethoxylates. Best options are quality wetters that have low foam formulations, avoiding problems with froth overflowing the tank.
Specialist wetters such as Prowet® 1040 (Wetter TX) are used for use with glyphosate for control of certain harder to kill grass weeds.
Prosil® 1000 (Pulse®) is an example of an organosilicant based surfactant/penetrant that is used with fungicides , insecticides and herbicides. It acts as a spreader, wetter and penetrant, but has little sticking ability or rainfastness.
This is where there has been much change over the years with many people not keeping up with the changes in technology.
These are the original spray oils that represent the oldest technology. They act as wetters, spreaders and penetrants. They can cause some direct phytotoxicity seen as speckling on the foliage. Examples are Austec® Spraying Oil or Uptake® Oil.
The next improvements over mineral oils were the Crop Oil adjuvants such as Protec® Oil, or Synertrol®. These are based on straight untreated crop oils such as canola. They improve wetting, spreading, sticking and also greatly improve penetration of sprays.
These treated oils such as Protec Plus® represent the latest and best technology in crop oil adjuvants, using esterfied canola oil plus surfactant package to provide the broadest range of features and benefits. Lighter than ordinary oils, these products mix very readily with water. They provide the best available wetting, spreading, sticking, penetration, rainfastness, and drift retardation. Protec Plus also includes a low foam surfactant package. Promax®, a unique product is suited for use with very hard water, such as bore water due to its unique surfactant package.
Includes acidifying products such as acidifiers (Probuff® 700, LI 700) whose main purpose is to acidify the spray to improve effectiveness of glyphoste. They carry a basic surfactant package to provide a level of wetting and spreading.
More information is available on this website simply by going to Crop Protection and clicking on adjuvants.