The area sow n to oilseed rape has fluctuated in recent years from roughly 9,000ha to 12,000ha, partly due to weather. The overall area is up in 2021 and this may not just be a coincidence of weather.

The past number of years have brought considerable improvement to the genetic capability of the crop and growers are beginning to recognise this.

The most obvious and measurable consequence is the ongoing improvement in yield potential. Many more growers are now exceeding the previously elusive 5t/ha target and genetics play a big part in this, coupled with a range of other beneficial traits.

Perhaps the most critical of these is the presence of pod shatter resistance in most, but not all, varieties. This provides insurance against things going wrong at the end that might previously have caused considerable seed loss ahead of harvest.

Resistance to light leaf spot and phoma have also been considerably improved and many varieties carry these traits. Resistance to sclerotinia is also beginning to appear in some varieties.

However, the trait that may be most beneficial to yield potential is turnip yellows virus (TuYV) resistance. This is now present in some of the newer varieties coming through. This trait seems to help a crop to realise its potential.

Evaluation of varieties

Assessing the area makeup of oilseed rape varieteis is more difficult than with cereals as all of the seed is imported. With cereal seed, very little is normally imported and native production is well documented.

It has also been the situation that the recommended list has not been the primary driver of variety choice for oilseed rape because some breeders did not put their varieties through the evaluation process. That has since changed and now virtually all varieties are tested for the recommended list and this provides additional assurance to growers.

Because winter oilseed rape is an 11- to 11.5-month crop, it is not possible to get trials harvested and produce a new recommended list ahead of the next planting season.

For this reason, the 2021 winter oilseed rape recommended list is assembled using information from the three previous harvests. Because of this, candidate varieties are often grown commercially before recommendation.

As well as the actual varieties that are recommended, many others are being evaluated and after two years of assessment these varieties become potential candidates for recommendation after their third year.

Stem length, strength and stiffness are important characteristics that can be managed with the help of growth regulators.

The varieties now in their third year of assessment include LG Ambassador, LG Artemis, Aurelia, Darling and PT279 CL.

The three recommended varieties – Anastasia, Aquilla and DK Expansion – will be accompanied in the market by varieties not yet recommended but most are in the trialling system. These will include Acacia, Aurelia, DK Exstar, DK Expectation, DK Imprint CL, LG Ambassador. LG Artemis, P303 and PT279 CL.

2021 recommended list of winter oilseed rape varieties

The 2021 winter oilseed rape recommended list sees four varieties dropped and one variety added with provisional recommendation.

The four varieties that have been dropped since 2020 are Alizze, Dariot, PX113 and SY Harnas.

The newcomer is the hybrid DK Expansion.

This comes with high yield potential and while the variety is only just recommended, it has been grown widely for the past few years.

Interest

It is possible that we will see an increased interest in this crop for 2022, especially for autumn planting.

So it is important to have a basic knowledge of the varieties on offer and their strengths and weaknesses.

Details of the varieties are shown in Table 1. Recommended varieties

  • Anastasia: this is a conventional or non-hybrid variety with good yield potential. Its early vigour is ranked as moderate and it is the shortest variety on the recommended list. It has very good lodging resistance and good stem stiffness. Anastasia is late to flower but it has an early maturity rating. It has good light leaf spot resistance and seed shedding resistance.
  • Aquila: this is a hybrid variety with high yield potential. It has moderate early vigour, with good lodging resistance and stem stiffness. It is early to flower and early maturing. It has good shedding resistance but only moderate light leaf spot resistance scores.
  • DK Expansion (provisionally recommended): this hybrid variety is the highest yielder on the list and it shows very good early vigour. It is the tallest of the three recommended varieties but it has good lodging resistance and stem stiffness. It is somewhat later to flower but still has an early maturity rating. It has good light leaf spot and very high shedding resistance (contains the anti-pod shatter gene) scores.
  • + The control varieties used were Anastasia, DK Extrovert and SY Harnas in 2018 and Alizze, Anastasia and SY Harnas in both 2019 and 2020. Yield and oil content are expressed relative to the mean of the control varieties (100 = mean of control varieties). The mean yield and mean oil content of the control varieties was 5.2t/ha and 45.1%, respectively, when adjusted to 9% moisture content.

    Non-recommended varieties

    The following is some pertinent information on the other varieties known to be in the market this autumn.

  • Acacia: this is likely to be one of two conventional varieties on offer, along with Anastasia. It is not yet in the Irish evaluation system but it has been performing very well across the water where it seems to be right up there with the best hybrids. It is by far the highest yielding of the conventional varieties in the UK and seems to exhibit many of the useful characteristics of hybrids. It has really good lodging resistance and exceptional stem stiffness. It has good light leaf spot resistance but only moderate resistance to phoma. It does not carry the anti-pod shatter gene and it is not resistant to TuYV.
  • Aurelia: this hybrid variety is in its third year of evaluation for the Irish recommended list. It yielded 109 and 112 in the past two years, so it looks very promising. It has a very solid package of traits, with good straw characteristics, early flowering and average maturity. It carries both the pod shatter gene and TuYV resistance, which are a great accompaniment to high yield potential. It has good light leaf spot and phoma resistance, but it is not top of the class for either.
  • DK Exstar: this hybrid is not currently in the recommended list evaluation system, either here or in the UK, so there is no independent experience of it yet. However, it is said to be high yielding with high oil content. It shows vigorous establishment along with rapid autumn development. It is said to have very stiff stems and be highly resistant to lodging. It carries the pod shatter gene and is highly resistant to light leaf spot and phoma.
  • DK Expectation: this hybrid is in the variety evaluation systems both here and the UK. It is in its first year here in Ireland so there are no previous relative yields to guide us. It has been yielding well in the UK but does not seem to like more northerly locations. It has good resistance to lodging and quite stiff stems. It is very early to start flowering but only moderately early maturing. As with all other DK varieties, it has very good resistance to light leaf spot and excellent resistance to phoma. It is resistant to TuYV.
  • DK Imprint CL: this hybrid variety is in year one of its evaluation here and is new to the UK AHDB list. There are no Irish yield figures yet but UK results suggest it has broadly similar yield to PT279 CL. It is regarded as being good against lodging but its stem stiffness before harvest might only be moderate. It is slightly later to begin flowering but its maturity is average. It shows excellent resistance to phoma but it is only moderately resistant to light leaf spot. It also has the pod shatter resistance gene. Its rapid autumn development is said to help with later drilling, tough soil conditions and moderate pest issues.
  • LG Ambassador: a hybrid variety in its third year in the recommended list system. In 2020 and 2019, it yielded 107 and 113 relative to controls, so it has been showing excellent yield potential to date. It has very good standing power, along with high resistance to light leaf spot and phoma. It is resistant to pod shatter. It is early flowering and relatively early maturing. It is resistant to TuYV.
  • LG Artemis: another hybrid variety and a sister variety to LG Ambassador. It is in its third year of recommended list trials here, with previous yields of 106 and 114. It has excellent yield potential. It seems to have good stem stiffness and lodging resistance but it is relatively tall. It is relatively early maturing and average for earliness of flowering. It is moderate against light leaf spot and phoma and resistant to TuYV.
  • PT303: this is a Pioneer or Corteva hybrid variety and it is in its first year in the evaluation process here, so there are no independent yield numbers yet. It is not on the UK list yet either, so there is little in the way of independent data available. It is said the be very strong on lodging resistance, as well as having good disease resistance. It is said to be resistant to Sclerotinia.
  • PT279CL: another Pioneer hybrid and a Clearfield variety, as designated by the CL suffix. It is on the UK recommended list and it is in its third year of evaluation here, where it had a relative yield of 95 in the past two years. It has very good straw characteristics with slightly later flowering but relatively early maturity. It would not be great against light leaf spot or stem canker and it does not have TuYV resistance.
  • There will also be small quantities of LG Aviron and the Clearfield varieties, Plurax CL and Phoenix CL, available.

    Variety improvement, combined with good canopy management, has the potential to deliver high yields of oilseed rape.

    Increase in margin potential

    The substantial increase in oilseed rape prices has significantly increased its margin potential this year. While many growers did sell a proportion of their rape forward at prices lower than the current values in excess of €500/t, the average dry rape price is still likely to be in the high €400s/t.

    Table 2 compares the margins for the main crop alternatives based on current prices. At a price of €480/t (green), a 4.5t/ha crop of winter oilseed rape would leave a gross margin of €1,122/ha based on the Teagasc costs. This is about equivalent to an 11t/ha winter wheat crop and for those who might average 5t/ha of rape, the €1,362/ha margin is still higher than a 12t/ha crop of winter wheat. The equivalent prices used here for cereals are €200/t for wheat and €190/t for barley and oats.

    While the figures for beans do include protein aid, the 2021 figures in Table 2 do not include the higher aid level that is likely to apply for 2021. This would add over €50/ha to all the numbers for bean margins.

    One of the big challenges of good break crops like oilseed rape is attributing the benefits that they bring to the following crops. This would be a yield benefit in the case of any following cereal but there could also be an additional price premium benefit as a seed crop or gluten-free oats. The option to grow a high-margin crop which has the potential to add substantially to the margin of the following crop should be considered.

    Looking another year ahead

    The question now is whether or not the prices for all crops in 2021 can be repeated in 2022. History tells us that is highly unlikely but there are prices available today which support price levels that are much higher than what we have seen in recent years.

    Using current November 2022 prices for cereals and oilseed rape, I have guesstimated prices for 2022 on the basis that they are available today.

    Table 3 provides an estimate of margin for 2022 based on November 2022 prices. The crop values used are €180/t for wheat, €170/t for barley and oats, €400/t for oilseed rape and €235/t for beans. Straw values are kept the same but costs for seed and fertiliser have been increased.

    All margin estimates are well down for 2022 but good crops of oilseed rape are still up there with winter wheat and it will be much easier to get higher yields of wheat with the help of break crops and good soil management.

    The aid figure for beans is included at the basic level but this could alter either up or down depending on the total area of protein crops that will be declared next year.

    In short

  • One new variety has been added to the recommended list for 2021 plantings.
  • There will also be many non-recommended varieties in the marketplace, some of which may be recommended next year.
  • Higher prices for rape have pushed this crop into the top margin category for 2021.
  • Current prices indicate that oilseed rape could again fare favourably in 2022.