There are many uncertainties around tillage farming currently with weather, grain markets, land supply and input costs being the most important ones – all of which are key ‘core’ elements in successful and profitable cereal production.

Good decision making is another key part of tillage farming but it is much easier to execute when there is more certainty around the fundamental aspects – so 2024 is a unique season with growers facing the challenge of good decision making in such a chaotic environment.

Good disease control in cereal crops is very important in the Irish climate – the uncertainty of weather brings the risk of high disease incidence as our cool moist climate can be ideal for wet weather diseases in barley. It’s not all a negative – this cool moist climate is also ideal for high barley yields. Climate is changing and this is another big challenge for crop yields and good farming. The last nine months of weather speaks for itself.

A cool moist climate is our comparative advantage compared to growing barley just about anywhere else in the world – it’s ideal for higher yield and better quality – and it’s a unique advantage – and we must not forget this.

Dr Tom McCabe on barley yields.

The advantage is real – good barley crops, winter or spring, grown on good land anywhere in Ireland can be very high yielding and should have high quality and be pushing the genetic ceiling of barley yields in a good summer. A good summer for cereal yields is cool and bright – which is normal, nice weather – nothing spectacular needed but it’s all about a nice, bright June and July.

High Yields can have Unexpected Beginnings

  • Don’t let a messy late spring and waterlogged fields in March (which are terribly frustrating) make one think a good barley crop won’t happen. Winter barley can find so much recovery in good late-spring / early summer weather and the first ever 10t/ha spring barley trials we harvested on heavy land at UCD Lyons Estate was early May drilled cv Cooper after the very wet spring of 1994 – but the months that followed were great weather for cereals and big yields followed – this scenario could not have been imagined in the endless wet weeks of March or early April. One key footnote here – the conditions at drilling in May: the seedbed / the tilth / the crop emergence were really nice – patience was rewarded.
  • Fast forward 20 odd years to 2013. There was a fodder crisis and bad spring but spring barley yields to remember. UCD Boortmalt trials with delayed drilling until mid-April in south Wexford delivered stunning barley crops on lovely brown earth and yields touching 11t/ha. So it’s important to remember the highs but also to recall the unlikely origins they often emerge from.
  • Ideal climate for disease

    So, a cool bright and moist weather pattern is perfect for barley, but this cool moist climate is ideal for wet weather disease and this is also a reality and barley growing must be approached in this context. The diseases in focus are Rhyncosporium, net blotch and ramularia leaf spot.

    Whether it’s a winter barley or spring barley crop all three diseases are important and need attention. Rhynco likes wettish springs and early summers, net blotch is favoured by warm and moist periods and ramularia seems to thrive once it’s not a long dry spell in summer. All can hit yield and quality hard, but crop protection options are good and effective and are very cost effective.

    Fungicide resistance risk is everywhere with these key barley pathogens and has been a constant and evolving threat for the last 30 years, but it’s well managed by an IPM approach which is carefully planned and well executed fungicide programmes combined with good overall crop agronomy

    Spring barley responds to fungicides

    As reported in last year’s Crop Protection Supplement the DAFM variety evaluation team reported on an important and very comprehensive three year study (2020-2022) on yield response to fungicide use across three spring barley cultivars with an average yield response of 15-20% recorded.

    Spring barley receiving a T1 fungicide.

    Planet is the outstanding spring barley of its era. It has at best moderate disease resistance and it continues to be the most important current spring barley variety. Planet gave an average grain yield response of 25% in this study, which is highly cost-effective on a yield basis before factoring in any upside on quality. This is a very noteworthy outcome on yield response for a three-year period in what I would describe as low-moderate disease pressure with extended ‘drought’ periods recorded in both 2020 and 2022. This study clearly shows that spring barley is not a low response crop to fungicide use.

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    Timing is more important than product choice

    Timing in the early part of the season is about keeping Rhynco and net blotch to the lower leaves and protecting the middle crop canopy. Remember fungicide options are very good here – and will give a high level of control once the basics of the fungicide programme are followed correctly, so keep the fungicide rates at moderate levels and get sprays well-timed.

    Triazole fungicides have played a huge role in barley disease control for the last five decades and are still central to the programme, with prothioconazole and metfentrifluconazole the key actives currently.

    Prothio has been a uniquely important chemical for barley disease control and continues to be a key base to a fungicide programme with its broad-spectrum activity across all key diseases. Metfen comes into play with its extra efficacy for ramularia control. The combining of an azole with a strobilurin or SDHI is a very good technical approach for barley disease control and trials in Ireland in recent years show very clear complementary benefits in disease control efficacy from the mixture of products. A key level for disease control in barley is 80% and the fungicide mixture approach brings the efficacy to this threshold consistently in trial studies with 85-90% control achieved with the most effective treatments in UCD trials in 2022 and 2023. The fungicide mixture products do consistently add to the cost-effectiveness of the T1 or T2 treatment and also have a very important role in fungicide resistance management.

    The head emerging on barley.

    It’s basically the best way to protect each of the chemistries in a high resistance risk scenario.

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    While there is technical merit in getting into the complexity of individual active ratios and grams of components on a product-by-product basis when looking at fungicide options it is exhaustive, and it’s more important to have a treatment which is well-balanced combining two or three key chemistries.

    Folpet

    Folpet is important – but needs to be used with skill.

    Ramularia control is trickier since chlorothalonil products left the market and Folpet is the replacement contact option and it’s a good chemical and should be in the programme – it’s proven its worth repeatedly in trials. But it’s much less ‘flexible’ than chlorothalonil which was so good you invariably always got a good result no matter how you used it.

  • Folpet is less rate flexible, less timing flexible and less persistent in relative terms. On both winter and spring barley where a high-pressure ramularia scenario is expected a split-timing approach may be a good strategy and the total Folpet dose would be in the range 1.5-2.0l/ha.
  • If it’s a single application of Folet in a T2 treatment then the timing needs to be very sharp, in the flag leaf to first awns peeping window, and the rate needs to be kept robust to deliver persistence of control.
  • Folpet will add to the performance of all fungicide products currently on the market and it’s also a very important product for resistance management as resistance to ramularia is widespread at moderate levels in all of the other chemistries.
  • There are no easy outs on ramularia control as it can be tricky at both ends of the season. That’s the reality since chlorothalonil lost its approval – but it can be achieved to a high level once one is sharp on timing and understands the need for protection over an extended period of the season – it needs to be planned from early flag leaf (think T1.5) on winter barley and needs to be watched to the bitter end in late-drilled spring barley so there is no scope for shortcuts here. This may mean more than one treatment targeting ramularia control for both crops, so think with flexibility of timing and dose.
  • Late-sown spring barley crops are very prone to ramularia as the crop stress levels tend to increase into mid-summer.
  • The pathogen has its ideal conditions with temperature and humidity in mid-summer and also inoculum and incidence on barley crops peak later in the season so these crops need proper protection. The spend can be modest – if it’s a two-spray approach the fungicide dose rates are flexible on a crop-by-crop basis.