Iprodione loss - The best thing that could ever happen - According to John Handley, Tehchnical Manager

John Handleyin Technical

Just in case you've been living on Mars for the last year, iprodione, the Active Ingredient (AI) in Cavron Green, Chipco Green, Emerald Turf, Green Turf King, Interface, MAC-Iprodione 255 SC, Mascot, Rayzor, Panto, Recover and Surpass Pro, is being withdrawn for use on managed amenity turf. Iprodione is a broad spectrum fungicide for a wide range of turf diseases, including anthracnose, dollar spot, fusarium patch, leaf spot, red thread and rust.

From a commercial perspective, the products which contained iprodione have been a steadfast part of the portfolio of all the major suppliers within the amenity sector. This chemistry has been a vital part of the armoury against turf disease for turf managers for decades. These products will be available for sale until the 5th March and can be used until the 5th June.

Turf managers will be facing this autumn deprived of what has become, for some of them, an integral part of their response to disease pressure. And, whilst the problems of September seem a million miles away, it is how we manage this transition to living without these products that may determine if, in the long term, they keep their jobs.

If you're reading this, then I suspect that it may be something that has concerned you and you may even be contemplating strategies to resolve this deficit. However, there will be managers out there who are resolutely refusing to contemplate a future without iprodione. Conversely, there are some people who may be thinking that this is the best thing that can possibly happen. Hopefully, by the time you've finished reading this article, you'll understand the justification behind the latter remark.

Fusarium

In a perfect world, there wouldn't be a need for fungicides: we could alleviate the stresses on the plant before they occur, reduce the amount of play, increase the height of cut, carry out maintenance operations at optimum times, and all with unlimited resources, but that's not the reality for anyone and, therefore, it's incumbent on every manager to give over a proportion of their strategic thinking as to how they will manage the threat of disease.

For some, the threat of a virulent pathogen is an opportunity to push out a weak and susceptible host. I recall the blank look on the faces of a group of Scottish links course managers when I mentioned turf disease Microdochium nivale. I'm from the era when it was referred to as Fusarium and Chipco Green was called Rovral Green and, coming from the Midlands where the idea of welcoming this disease, which was the scourge of Poa annua dominated greens, was as novel as the notion of a Caribbean holiday. I knew it occurred, but just not to me.

Turf disease does occur within the context of winter sports pitches, but the favoured grass species that is used in that context is Perennial Rye-grass. As a species, it's naturally resistant because of the waxy cuticle and capacity to outcompete pathogens even at low temperatures. Therefore, it is other factors, such as intense grow-in periods, reduced natural light and decreased air movement because of stadium construction, that tend to be the cause of disease within winter sports pitches.

The sector that is likely to most dread the loss of iprodione will be golf, and the cause of this distress is a set of practices which can only have come into existence because iprodione has been so extensively used. Many managers are so dependent upon iprodione that its withdrawal must lead to significant changes in the way they manage their turf.

Red Thread

There are credible people arguing that we're losing this AI because of our presence within the European Union. I'd point out that it is changes in the way AIs are assessed which has led to iprodione being withdrawn, because it has been found to be a possible cause of pulmonary problems and to be a probable human carcinogen.

When I started work, it was conventional to use mercury as a seed dressing and chlordane to control worms. Developments in our understanding of the way these products worked, and the potential hazard they presented, resulted in them being banned; improvements in knowledge drive development which has improved the working environment.

The last couple of decades has seen reductions in research and development within the British amenity sector. Development within the industry has been dominated by R&D that has found its way over here from the United States. This may continue whilst we lack a system that connects universities, PhD students in particular, and practitioners

The last couple of decades has seen reductions in research and development within the British amenity sector. Development within the industry has been dominated by R&D that has found its way over here from the United States. This may continue whilst we lack a system that connects universities, PhD students in particular, and practitioners. Companies need to invest in university research if they are to obtain credible methods and products.

Bringing a new product, based on new chemistry, to market is expensive and often takes more than a decade; there is a very strict registration process for fungicide and pesticide products. A significant quantity of data is necessary to scientifically prove that a product is not only completely new and different, but that it is fit for its intended purpose, and meets all environmental and safety criteria. Refining and re-testing is conducted with meticulous attention to detail from the laboratory, right through to field trials.

The dosage rate for all AIs is determined as the minimum effective dose: the days when the product was over-engineered for the circumstance are dwindling. All controls will work effectively in optimum conditions and it is, therefore, incumbent on the end-user to stack the odds in their favour: timing of applications is more critical and relies upon treating the disease in the early stages before symptoms are manifest in the plant. Managers will need to recognise this, and work with suppliers and agronomists who can advise appropriately.

Models have conventionally been used to help us think about turf diseases. The plant disease triangle (figure 1) is a model that demonstrates that all three aspects need to be present for disease to be expressed within the plant. A virulent pathogen operating within a favourable environment that contains a susceptible host will lead to disease. Focusing on any of these elements can help us reduce the likelihood of an outbreak, i.e. making the environment less favourable or making the host less susceptible.

Models already exist that can help us understand the pathogen and the susceptibility of the host, i.e. phenology models have existed within agriculture for decades e.g. Growth Degree Days, temperature and leaf wetness. Developed in the United States, where there is a strong background of incorporating science into the practical management of turf-grasses, the relative success obtained from developing and using these models will ultimately shape the outcome of which companies will be providing advice to turf managers in the future.

Other models can help us understand the various stages of disease and when we need to be targeting the various methods we'll be using (figure 2). Critically, the disease only becomes evident within the plant in the latter stages and preventative treatments will need to be focused on the first two stages.

Supplier relationships are important within the amenity sector and the technical knowledge of individuals, not only about their product range but also an understanding of plant health and disease management, will become increasingly important.

Turf managers that relied on conventional practices - note the use of the word conventional as opposed to traditional - will start to disappear. Sales people who lack an understanding of plant health and turf disease management will become fewer, particularly as an appreciation of the harm that overzealous use of iron can induce.

We will witness more products coming onto the market that state "they will do one thing" when the reality will be that they do something entirely different. As an industry, we have already embarked upon that journey and, although I welcome change, I also have grave reservations, particularly in the use of unregistered products which are being used to control problems without sufficient regard for the consequence of their use

Changing regulations, loss of professional Plant Protection Products and a lack of legal enforcement means that we're heading for an era of 'grey' products. We will witness more products coming onto the market that state "they will do one thing" when the reality will be that they do something entirely different.

As an industry, we have already embarked upon that journey and, although I welcome change, I also have grave reservations, particularly in the use of unregistered products which are being used to control problems without sufficient regard for the consequence of their use.

Not all of these 'grey' products will prove to be problematic and I imagine that it will lead to a stratification of the supplier network: managers will have suppliers they buy most of their consumables from, informed suppliers that work hard to provide reliable products and have a sophisticated knowledge on how these products interact, suppliers that offer specialist products, and 'dirty' suppliers that don't particularly care about the consequence of the commodities they sell as long as there's a profit to be derived.

Skilled managers will be able to communicate the implications of these changes and the need to address the shortfall in available tools and, as a consequence, they will progress within their careers. Throwing ones hands up in the air and declaring that "our arms are tied and that the tools to do the job are gone" is a poor defence; we are employed to find solutions, not pass on problems.

So why am I so excited about losing iprodione? For many, the loss of this curative fungicide will lead to an increased scrutiny of our own practices and on the advice we seek from suppliers and other professionals. Going back to develop our own knowledge, in the light of our experience, will hopefully prove to be a useful, if salutary, experience.

Innovations will come as a response to the changing practices; new ways of thinking about the plant, substrate, microorganisms and the environment; and the interactions that take place between all of these. We're entering an era of biostimulants which will necessitate an improved understanding of a set of complex processes.

This is occurring simultaneously with the adoption of technologies such as robotics, Geographical Information Systems (GIS) and remote sensors.

Many of these technologies have already been adopted within agriculture, and companies within the amenity sector are looking to capitalise on the experience gained there.

A project currently running at Harper Adams University is attempting to grow a crop from ground preparation through to harvest using machinery that doesn't involve people.

There are threats too. In these challenging financial times, the opportunity to reduce costs will be a significant driver. Younger greenkeepers will emerge who are more capable of adapting to these technologies and less accepting of the status quo. It will naturally become more data driven as technologies become adopted and course managers will be making decisions via computer or their mobile phone, aspects that require increased integration and connectivity.

Change is occurring within the amenity sector, and I commend the BIGGA committee responsible for putting together the "Continue to Learn" programme at BTME. The standard of talks was excellent, with many contributors getting to grips with the challenges that the industry faces; this is a valuable source of the lifelong education and professional development that is needed through these uncertain times and the best way they can support their members.

Change wasn't evident within the exhibition halls at BTME this year but, talking to various companies, there's a recognition that the changes that are occurring provide opportunities to improve. I suspect that the next decade will witness losses and gains and a response that will galvanise our industry so that we can continue to reinforce our reputation on the international stage.