Grey mold is caused by the fungus Botrytis cinerea.

The Colonizer® bio-fungicide contains a microbe (Trichoderma koningii Td67) which is a natural enemy of Botrytis cinerea.  The microbe was found on an organic vineyard in southern Tasmania which suffered less Botrytis than surrounding conventional vineyards.

Botrytis cinerea initially infects grapes by growing into the flowers at the time of pollination.   Trichoderma Td67 in Colonizer® is especially well adapted to colonizing the grape flowers, and it competes with Botrytis cinerea, resulting in as much as 80% less grey mold at veraison.

       

Above: a grape flower (left) and Botrytis cinerea spores germinating on a leaf (right).

Colonizer® is a certified input for organic farming approved by NASAA (download NASAA approval).

Timing of application.

Colonizer® can be applied to the crop at any stage of growth including flowering, bunch closure and veraison.  Application during flowering is the most important treatment as it will allow Trichoderma Td67 to grow into the pollen receptacle and colonise the inside of the berries to eradicate Botrytis infections.  Experiments show that the most effective time for flowering applications of Colonizer®  is at 80% capfall.  This is the time when the maximum number of flowers are open.

Some growers who are under very high disease pressure apply Colonizer® at both 20% and 80% capfall and this does allow Trichoderma Td67 to grow inside a larger proportion of berries and does provide a higher level of disease control.  The experiments are explained in the attached flyer.

Download information on  Application Timing.

Compatibility with other sprays

The compatibility with chemical fungicides also should be considered in planning use patterns for Colonizer®.   Trichoderma Td67 is a living fungus, it is compatible with most chemical fungicides, but a few chemical fungicides can reduce it's survival if they are applied right after Colonizer® is applied. 

The risk of this occuring is greatest in the week after flowering application, while Td67 is still growing into the flowers and the developing berries are very small with thin skins.  The risk is much reduced as the season progresses.  Normally only very minor changes to spray programs are needed.

Download information on compatibility with other sprays.

Application and storage

Colonizer® is applied using conventional spraying equipment and has been tested and shown to survive nozzle pressure up to 800kpa, so should be satisfactory for most sprayers.   Colonizer® is supplied in a 100g package which is the quantity to treat 1Ha.

Colonizer® contains a living fungus and care must be taken to avoid storage at high temperatures (such as in a car on a hot day, or in a hot tin shed).

Download Directions for Use.

Download Colonizer®  MSDS.