Organosilicone Surfactants – Use With Care
Organosilicone Surfactants are being actively promoted as excellent penetrators as well as good surfactants with superior rain-fastness properties.
They are definitely recommended for use with herbicides, which will have their effects considerably enhanced because of the properties of the organosilicones.
But then, nobody cares what happens to the weeds, and hopes that they die and disappear quickly and don’t come back!
Now, this is not the kind of approach for crops that we want to grow, nurture, and develop into quality, profitable products. And here are the reasons why:
- Organosilicones are so efficient at spreading materials, that they have been known to enter plant stomata and hydathodes - organs not normally penetrated by other surfactants.
Hydathodes are the tiny openings along the leaf margins that allow excess water to escape during the night. This type of action can lead to the penetration of unwanted bacteria that could cause serious plant disease problems1.
- Because of their rain-fastness properties: silicone type sealing of stoma, they would also act as anti-transpirants that would be detrimental to respiration, especially under warm and sunny growing conditions.
- Due to their enhanced penetration qualities, organosilicones would promote uptake into the stoma cells of spray materials that should remain on the surface(epidermis), hence possible damage or injury to the plant. They definitely should not be used in conjunction with oils or metals (fungicides).
Consequently, care must be exercised when selecting a surfactant or sticker/spreader, and one must first consider the safety and health of the crops.
Crop Protection, when promoted by commission and quota driven salespeople, can often turn into an "Oxymoron".
Auburn University: “researchers evaluated the use of an organosilicone surfactant to promote bacterial infection of leaves for biological weed control. The data indicate that a stomata-penetrating surfactant can facilitate bacterial infections in the absence of wounds and/or free moisture on the leaf surface. Further, in field experiments, high levels of infection were attained under hot, dry and sunny conditions.”