symptoms to occur as a result of product application


symptoms that resemble a ‘patch disease’. In these circumstances, inappropriate management using plant protection products will not only have a potentially adverse environmental impact in these situations but are also unlikely to manage the symptoms, allow the problem to progress unchecked, allow the possibility of repeated future problems and waste your resources of time and money. Once the disease is


accurately diagnosed, you can implement the most appropriate and effective management strategy. This could well involve an initial application of the most suitable plant protection product but more importantly, effect a change in your long-term cultural management plan to try and reduce the conditions that favour both initial fungal and disease development.


So what diseases should you be aware of? On fine turf areas, take-all patch disease is being increasingly seen on Poa annua plants. It has been known for many years that the fungus responsible for this disease can infect and cause disease in P. annua as well as in Agrostis species but


the disease has most frequently been seen in Agrostis species as these plants appear to be more susceptible to infection. The symptoms of take-all patch disease on P. annua will appear very similar to those on Agrostis swards but there are other, less common patch diseases that can also develop on P. annua and so it is always worth having the cause of the damage confirmed before any treatment in applied. There is increasing evidence to show that adequate availability of manganese can reduce the severity of take-all patch disease and may also lessen the development of the disease in new constructions, if added just prior to seeding. Manganese is used by the plants to produce compounds which are released around the roots and which serve as a defence against this particular root disease. The fungus, Gaeumannomyces graminis var. avenae, can effectively lock-up the manganese and make it unavailable to the plants, reducing the level of the plants defence against infection. A better result from manganese applications will generally be achieved with root uptake of the element


because manganese is immobilised in the phloem (the route of primary movement of materials from the leaf to the root). Fusarium patch remains


arguably our most common and most damaging turfgrass disease and over recent years, it has occurred with increasing frequency and severity on affected swards. The fungus that causes fusarium patch, Microdochium nivale, is able to live saprophytically on dead and decaying organic material and therefore, is able to respond rapidly to ideal environmental conditions that allow it to cause disease. The fungus will grow most actively under high pH conditions but any small increase in pH, even under generally more acidic conditions, will allow the fungus to grow more quickly than other organisms that normally ensure a healthy balance in the rootzone. In addition, this fungus is capable of growing at temperatures just above freezing and is not actually killed by frost. The ideal conditions for rapid growth of this fungus and for fusarium patch development and repeated cycles of frost and thaw or constant cool,


It is not unknown for


damp weather when turf growth is slow and the sward remains wet. Over the past few years, the winters have allowed many cases of ‘aggressive’ fusarium patch disease where treatments aimed at managing the disease have apparently failed. Due to the constant presence of this fungus and its ability to dominate the turf under cool, wet conditions, it is imperative that swards that are prone to fusarium patch disease are managed throughout the year to try and minimise favourable conditions from developing in the winter. Fusarium patch disease can and does develop all year round on certain turf areas, and where this is the case, it would be well worth while looking at nutrient input, the rootzone and surface drainage as possible reasons for the constant problem. Red thread disease appears to be increasing in occurrence on both fine and coarse turfgrass sward but in most cases, the damage is relatively superficial and restricted to the leaf. Only in extreme cases does the disease get in to the crown and cause lasting damage to the sward. In most cases it is possible to reduce the


Symptoms of fusarium patch


disease including yellowing plants, watersoaked leaf tissue and aerial mycelium of the fungus


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