It is likely that the greatest demand will be for both Propino and Sy Taberna.
There is very little difference in yield potential between the varieties, with Frontier and Snakebite at 99; Cropton at 100, Quench and Propino at 101 and Sy Taberna, the highest yielding, rated at 102.
However, that yield difference is enough to maintain the average annual yield increase of 1-1.5pc referred to above.
Propino and Sy Taberna are both tall-strawed varieties, similar to Cropton and rated at 5. Quench and Snakebite are still rated at 6 and Frontier has maintained its 7.
Resistance to lodging is highest with Snakebite and Sy Taberna, so these varieties are likely to stand better on fresher land where it is more difficult to predict organic nitrogen release. All varieties, with the exception of Snakebite (7), have a rating of 5 for straw breakdown.
Frontier is the earliest ripener with a rating of 7 and Sy Taberna (5) the latest . The other four varieties are rated at 6. Sowing early ripening varieties first will help to give an earlier start to the harvest.
Cropton and Quench have maintained their mildew resistance of 7 and have been joined by Sy Taberna. Frontier and Snakebite are rated at 5 and Propino has a 6. Select a variety with good mildew resistance if you are sowing late. Both Propino and Sy Taberna are rated at 7 for rhyncosporium, similar to Quench. The other recommended varieties all stand at 5. Select varieties with the higher resistance for wetter and more sheltered fields and in coastal areas.
In areas where brown rust is a problem, varieties with poorer resistance, such as Quench and Propino, need to be managed carefully. Snakebite has the highest resistance (7) and Cropton, Frontier and Sy Taberna all come in at 6. All varieties, with the exception of Cropton at 6, are rated at 7 for Net Blotch.
The 1,000 grain weight of varieties has increased in recent years from an average of 49g in 2009, 48g in 2010 and 50g in 2011 to 51g for this year.
The larger the seed the greater the seeding rate in order to get a similar plant stand. Propino has the largest grain size, followed by Snakebite, Cropton, Frontier and Sy Taberna, which are all similar in size. Quench is the smallest by far.
Based on the 1,000 grain weights on the recommended list, and assuming that you are sowing into good seedbeds, an expectation of 90pc establishment, (table 1 above) is a good guide.
The lower target of 250 plants/m2 is satisfactory for early sowing under good conditions into fertile soils.
Seeding rates must be increased for poorer conditions, later sowings or any factor which may reduce tillering or tiller survival.
Before you sow, do your own seed counts and check the label before finalising seed rates.
The increased acreage of winter wheat and disappointing results for spring wheat last year are likely to lead to less interest in this crop this year.
However, if conditions come good this month it will still be very tempting to sow land after potatoes or ley ground. Spring wheat has generally presented less of a challenge and lower costs in disease control. Goldcrop is the agent for three of the four varieties on the recommended list.
Estimated certified seed availability is 37pc Sparrow, 30pc Trappe, 22pc Granary and 11pc Raffles. Despite the fact that it is the oldest variety on the list, Trappe is the highest yielding variety at 103, Sparrow is at 101, Raffles 97 and Granary is 96.
All four varieties have similar straw-length strength, with the exception of Trappe, which is taller. Raffles is the earliest to ripen followed by Granary and Trappe and then by Sparrow. Sparrow is moderately resistant to mildew, while the others are all moderately susceptible. Raffles is weakest on septoria while the others are moderately susceptible.
Trappe is weakest on Yellow Rust (6) but both Granary and Sparrow, based on limited data, have good resistance (7) along with Raffles (8). All varieties have a similar rating of 6 for sprouting. Both Sparrow and Trappe are rated good for milling and baking quality.
There is considerable variation in grain size. Table 2 (above) indicates differing seeding rates in order to establish similar plant stands. But as for barley, check the seed count of your seed before deciding on seeding rates.
Barra is still commanding a considerable market demand. Despite the fact that it has been on the recommended list since 1985 and its yield potential has slipped to 94, Barra comprises 37pc of the certified seed availability in 2011/2012.
Husky, rated at 103, and comprising 28pc of seed availability, is generally sold out. A considerable amount of both these varieties was sown last autumn.
The availability of Circle, rated at 102, and Evita, at 103, may be somewhat better. There is very little of the highest yielding variety, Binary, at 108. Both Binary and Circle entered the recommended list last year and are still provisionally recommended this year.
Circle has a tall straw similar to Barra, but its resistance to lodging at (8) is substantially better than Barra (4). Binary has a short straw similar to both Evita and Husky (8) but is moderately susceptible to lodging. However, its rating of 5 is still better than Barra. Both Binary and Circle are rated at 6 for straw breakdown, similar to Evita and better than both Barra at 4 and Husky at 5. Both Binary and Circle have the same ripening rating as Barra at 6.
Circle has a disappointing 4 for resistance to mildew, but bear in mind that we have been managing Barra successfully with a score of just 3 for several years. Binary has good resistance to mildew at 7. All varieties are rated as 4 for crown rust with the exception of Binary, which is rated at 5.
Barra and Husky both have a relatively small seed size and should be sown at 150kg/ha or 9.6st/ac in order to establish 350 plants/m2. Evita, Binary and Circle have larger seeds and should be sown at 165kg/ha or 10.5st/ac to achieve a similar plant stand. Check individual seed lots or do seed counts before finalising seed rate. When it comes to hectolitre weight (kg/hl) Barra still stands out on top with 54.9. Binary has a rating of 53.8 and Circle 53.2.
Finally, if you are doing home saved seed it is important to pay royalties of €42.74/t for wheat, barley and oats. Consult the website www.pvdo.ie/ for further details on royalty payment and www.irishseedtrade.ie/ for details on certified seed.
Patrick J Phelan is a member of ITCA and may be contacted at email@example.com