NGIA recently commissioned the NSW Department of Primary Industries to undertake research around the efficacy of common water treatment disinfestation measures used in the Nursery Industry.
The report compared the efficacy of three treatment methods;
- Chlorine (sodium hypochlorite NaOCl),
- Chlorine dioxide (ClO2) and
- UV-C radiation.
The different treatment methods were employed using distilled water and dam water with a variety of pathogens and their respective propagules. The pathogen species included;
- Clavibacter michiganensis subsp. michiganensis
- Alternaria alternata
- Chalara elegans (Thielaviopsis basicola)
- Colletotrichum gloeosporioides
- Cylindrocladium sp.
- Fusarium oxysporum
- Phytophthora cinnamomi
- Pythium aphanidermatum
It was found generally that higher rates of treatment and/or longer exposure times were required for effective treatment of pathogens in dam water. This was attributed to variations in pH and organic matter present in the dam water. Likewise the report highlights treatment response variances between not only different pathogens but also different propagules of the same pathogen.
This range of responses reaffirms that the selection of an appropriate water disinfestation system is influenced by a number of factors including; water quality (pH, turbidity), plant species grown, pathogens present and the hygiene practices of the nursery.
The full report is available on the NGIA website and a Nursery Paper on this topic will be published in August. This nursery paper will be available through the print publication Hort Journal Australia and electronically through the NGIA website.
This work has been funded by Horticulture Innovation Australia Limited using the nursery industry levy and funds from the Australian Government.