Yields of all varieties are expressed in the tables as percentages of the control.  For all crops the control is calculated as the mean (average) fungicide-treated yield of the control varieties that are selected on a UK basis.  Untreated yields are expressed as a percentage of the mean of the fungicide-treated controls also.  Both fungicide-treated and untreated yields represent the mean performance of the varieties in trials during the five-year period 2007 to 2011.

Fungicide programmes are applied to treated trials to keep disease incidences below 5% infection of the leaf area. Treated yields indicate the potential yield of the varieties in the absence of disease. Plant growth regulators are also applied to treated trials of winter wheat, winter barley and winter oats where the risk of lodging is high.

In untreated trials, where no fungicide treatment is applied, natural infections by a number of diseases may occur at various stages during the growing season. Varieties have differing levels of infection because they carry different types and levels of resistance to each of the diseases. Infection by disease reduces grain yield potential. Differences in yield between varieties in untreated trials are normally greater than in treated trials. Comments on untreated yields in variety descriptions refer to their performance relative to other varieties when untreated.

Growers have different approaches to the use of fungicides. Some prefer a programme that protects completely against all disease infection. Yields in the treated trials indicate which varieties are likely to give the best performances with this approach. Others prefer to use chemicals as and when disease occurs. Yields in the untreated trials indicate which varieties are likely to need fewer applications of fungicide in order to produce high yields and, conversely, where risks are greater if less-than-complete control of disease is achieved.

Information presented in the tables on specific weight and 1000 grain weight of spring barley, winter barley, winter wheat, spring oat and winter oat varieties and on kernel content of spring and winter oat varieties, is from the fungicide treated trials in Northern Ireland. Specific weight, measured in kilograms per hectolitre (kg/hl), is an important quality indicator when selling grain. If the specific weight of a crop is low, it may not reach trading contract requirements. For winter and spring oats, specific weight is determined on pre-cleaned grain. Although individual crops will vary, the information on specific weight, grain weight and kernel content, presented in this booklet, shows accurate relative values for the varieties.

Oat screenings can be important when selling grain to the quality market. Oat varieties are screened over a 2mm sieve for 15 seconds and the proportion passing through is recorded as a percentage. These fluctuate greatly from season to season. Empty husks (that is grains that fail to develop kernels) and free kernels may be present in harvested oats and are unwanted in milling. All current spring oat varieties produce few empty husks but vary in their tendency to produce free kernels. Some of the winter oat varieties are particularly prone to producing free kernels and some also produce empty husks. Details are provided in the variety descriptions of tendency to produce free kernels and/or empty husks.

Straw length is based on data from untreated Northern Ireland trials (except for winter oats where data from the fungicide-treated, but without plant growth regulator, trials are used). Straw length is expressed in centimetres relative to Quench for spring barley, Firth for spring oats, Saffron for winter barley, Robigus for winter wheat and Dalguise for winter oats.

Straw yields are determined from one spring barley and one winter barley trial each year. For spring barley, straw yields are expressed as low (less than 3.3 t/ha), intermediate (3.3 to 3.6 t/ha), high (3.7 to 4.0 t/ha) or very high (greater than 4.0 t/ha). For winter barley, straw yields are from the fungicide-treated plots in trials that also received a plant growth regulator and are described as low (less than 3.75 t/ha), intermediate (3.75 to 4.5 t/ha) or high (greater than 4.5 t/ha).

Standing power is calculated using both lodging and leaning data and expressed on a 1 to 9 scale, where a high figure indicates good standing power. Straw characteristics, such as brackling (in oats and barley) and necking (in barley only) are referred to in the variety descriptions. Brackling is buckling in the lower part of the stem and necking occurs directly below the ear. Brackling need not be damaging unless the ears lie on the soil surface. Necking can be more serious if a clean break occurs leading to ear loss in bad weather. These straw characteristics are determined from untreated trial data.

Resistance of varieties to disease is expressed on a 1 to 9 scale in the tables. A high figure means that the variety is very resistant. The resistance of varieties to other diseases is referred to in individual variety descriptions where necessary. Resistance ratings to disease are drawn from naturally occurring field infections in trial plots in Northern Ireland to which no fungicides were applied. Mildew, yellow rust and Fusarium ear blight scores in winter wheat are taken from the HGCA Recommended List 2012 due to insufficient disease in Northern Ireland trials.

Disease incidences on cereal crops in Northern Ireland tend to be more variable from year to year and from crop to crop than in Great Britain. There can also be a high degree of variability between trial sites. In Northern Ireland, crops emerged surprisingly well out of the very severe winter in 2010-11. March and April proved challenging though, with only 50% of rain falling compared to the 1971-2000 average. In April, the monthly mean temperature was 3.50C higher than the long-term average. This dry, warm weather led to slow development of the wet weather diseases. A summary of cereal disease incidences in the Northern Ireland trials in 2011 follows.

May and June were largely disease-free for the spring barley trials in 2011 and Rhynchosporium levels were lower than in 2010. Traces started to appear in all trials by the end of June with Strabane being worst affected, all varieties being infected with a maximum of 20% in Optic and Doyen. At Coleraine, maximum infections of 6% were recorded in Garner and again all varieties were infected. At Ballywalter and Crossnacreevy, infections were much lower, many varieties having none.

Ramularia was once again the most severe disease in terms of severity and the number of varieties infected. It is a late-season disease and symptoms generally appear post-flowering. By the end of July, all varieties in all trials were infected. At Ballywalter, all varieties had at least 20% infection, with a maximum of 42% in Summit and Odyssey. At Strabane and Coleraine, infections ranged from 10% in Doyen to 30% in Moonshine and from 35% in Propino to 7% in Westminster, respectively. At Crossnacreevy, levels of Ramularia were lower with Waggon, Armada and Dandy having 4% and Propino and Quench having more than 15%.

Mildew and net blotch were less widespread in 2011. There were traces of mildew at the end of June at Crossnacreevy and Ballywalter in Doyen, Optic and Propino. By the end of July mildew had increased to 17% in Optic at Crossnacreevy. There was no mildew recorded at Coleraine and at Strabane there were traces in just one variety, Panther. Traces of net blotch were recorded in a few varieties in Crossnacreevy. At Strabane, there were traces of this disease in most varieties with up to 4% in Summit and Propino.

Mildew was not observed in the spring oat trial until the end of June. Significant levels of infection were recorded in Atego (67%), Rozmar (20%) and Ascot (18%). Canyon, Husky and Firth had no mildew. There was no crown rust or Septoria avenae recorded in 2011 and scores for these two diseases are based on data from 2007-2010.

Ramularia was the most severe and widespread disease in winter barley in 2011. At Limavady significant levels were recorded in susceptible varieties (Retriever 25%, Pearl 15% and Florentine 9%). At Hillsborough all varieties were affected with the highest infection recorded in Pelican (17%) and the lowest in Matros (2%). At Downpatrick Ramularia was also the dominant disease reaching 18% in Sequel, although many varieties, (e.g. KWS Cassia, Saffron, California and Matros) had negligible levels of infection.

Rhynchosporium was slow to establish in 2011 but by mid-June there were significant levels in susceptible varieties such as Retriever, Camion, Saffron and KWS Cassia. Levels were highest at Limavady (with a maximum of 17% in Retriever in mid-June) and lowest in Downpatrick (maximum of 11% in Camion by the end of June) with many varieties, for example Volume, Florentine and Matros, having none.

There were significant levels of mildew recorded in Saffron and KWS Cassia at Hillsborough and by the end of June traces were beginning to develop in Saffron at Downpatrick, but none was recorded at Limavady or Crossnacreevy. Incidences of net blotch and brown rust were even lower. Net blotch was recorded at Downpatrick only – with traces of this disease being recorded in Pearl, Flagon and Retriever. Traces of brown rust were recorded in just one variety, the 6-row Escadre, at Limavady.

Septoria tritici, the main disease in winter wheat in 2011, was slow to develop due to the very dry spring. By mid-June, however, infections at Crossnacreevy were as high as 20% in Chilton. Conqueror, Denman, KWS Santiago, Beluga and Gallant all had infections over 10% with most varieties having at least 5%. Stigg was the only variety that had low levels of infection (<2%). There was some late Septoria development in the treated trial (which had received a comprehensive fungicide regime) with many varieties, including JB Diego, Kingdom, Beluga and Ketchum, having >10% infection. Stigg was the least affected with only 2%. At Limavady in the untreated trial, Ketchum, Duxford, Gallant, Cocoon, KWS Santiago and KWS Solo all had Septoria infections of more than 10% by mid-June. Only Stigg had levels of less than 1%. In the treated trial at Limavady, Kingdom, Cocoon, Gallant, Oakley, Duxford and KWS Santiago all had infections over 7%, with Stigg having none and Alchemy only 0.4%. Disease levels at Downpatrick were much lower than at Limavady or Crossnacreevy, with the highest infection of Septoria being 10% in Cocoon in the untreated trial. Several varieties, including Robigus, Grafton, Relay, Stigg and Monterey, had less than 1% Septoria. In the treated trial, only Chilton and Cocoon had more than 5% Septoria.

Yellow rust was recorded in three varieties at Crossnacreevy. Worst affected was Oakley with levels of infection of 25%. Robigus and KWS Santiago had 8 and 7%, respectively. Traces of yellow rust were also found in Oakley at Downpatrick with none being recorded at Limavady.

There were no other diseases recorded at significant levels on winter wheat in Northern Ireland in 2011 and scores for mildew, yellow rust and Fusarium ear blight are based on HGCA UK-wide data.

No disease was recorded in the winter oat trial in 2011 and disease scores are based on data from 2007-2010.

Spring barley varieties differ in maturity by approximately two weeks from earliest to very latest. There are only minor differences in maturity amongst spring oat, winter barley, winter wheat and winter oat varieties. Maturity of varieties is included in the tables for all crops as early (E), intermediate (I) or late (L) to ripen.