Tech Notes Issue 2 - Take All
Early start for take-all patch symptoms
Due to the warm spring and early summer, take-all patch symptoms were starting to be noted in early June this year, a full month ahead of when we normally see the first symptoms in Yorkshire, for example.
View GreenCast details of take-all patch
Take-all patch is most common on newly established golf greens, especially on sand based rootzones where the pH is more alkaline. This is due to a lack of antagonistic fungi and bacteria in the rootzone. As the profile matures, the dominance of the pathogen that causes take-all patch (Gaeumannomyces graminis) diminishes and a natural equilibrium forms.
|The brown rings of take-all patch can seriouslyaffect newly established greens, or turf under soil-induced stress.|
However, if the equilibrium is upset, G. graminis can dominate the rootzone again and take-all patch may re-emerge. I have most commonly seen this occur following the application of alkaline materials, such as lime or, in one case, where an irrigation water acidifying unit malfunctioned, resulting in alkaline irrigation water being unwittingly applied.
Fungicide with systemic properties will be required to
get down to the roots and kill the take-all patch pathogen,
reports Dr Ruth Mann.
If take-all patch occurs, changes to some management practices can help to alleviate the problem. Fertilising with ammonium forms of nitrogen, rather than nitrates, can help reduce the severity of attack.
Ensuring the grass plant has sufficient manganese is also important; manganese can be bound up at high pH and unavailable to the plant. Gaeumannomyces graminis also actively oxidises manganese, making it unavailable. Therefore, by supplying more manganese in a form usable by the grass plant, symptoms may not be as severe.
Fungicidal control of take-all patch can be difficult as the active ingredient must be able to get to the roots where the pathogen has colonised. HERITAGE (azoxystrobin) is systemic and can be absorbed by root, stem and leaf material, enabling the active ingredient can get to the pathogen and control take-all patch.
HERITAGE is the only fungicide in the UK that has full label approval for control of take-all patch.