At that time the company didn’t use Huwa-san technology to disinfect the irrigation water. Most greenhouses have irrigation systems with long pipes in which the water stands still quite often and when no qualitative disinfectant is present in the water, microorganisms get the chance to multiply and form a biofilm. Plant pathogens, such as the fungus Fusarium spp. or the water mold Pythium spp., are given free rein. These two pathogens can cause damping off of tomato youngplants, also called ‘seedling disease’.

Nursery for Processing Tomatoes

The challenge
Damping off can be caused by the fungus Fusarium spp., but also by Rhizoctonia spp., possibly together with the water mold Pythium spp.. Damping off can be recognized by failed emergence of seedlings. When seedlings do emerge, their stems and leaves discolour gray to brown. Further the stems appears to be watersoaked and the plant will fall over, eventually leading to stunted growth and wilting of the seedling. An infected seedling will only occasionally survive to cultivate a vigorous plant.
Our solution
The company already used Huwa-San TR-50 at their location in Europe and decided to do the same at their location in California. Our Roam advisors proposed to install a dosing system to inject Huwa-San TR-50 into the irrigation system (Figure 2a). The recommended dosage Huwa-San TR-50 was based on the quality of the water system and measured at the end of the irrigation system (Figure 2b).


Using Huwa-San has not significantly improved my yield, but in terms of maintaining a residual and providing protection agains potentially catastrophic blight, it’s the most inexpensive insurance I could ever buy.
Giancarlo Tomelleri, Manager
Used products
Huwa-San TR-50 is a registered biocide. Use biocides safely. Before use, read the label and product information.