Choosing your sugar beet variety

Choosing sugar beet varieties for 2011

Making the choice of the right sugar beet varieties for your farm has never been more complex. As well as factors such as Rhizomania and Beet Cyst Nematodes to considered, there is the issue of the unusually high failure rate of official trials in recent years, leading to a paucity of reliable data.

The best "trial" is, of course, the one on your farm - growing the variety for yourself. Growers who have achieved individual record yields, or yields of more than 70 tonnes per hectare with a chosen variety, may understandably take some persuading to switch to untried varieties.  There is, after all, a big difference between the 3kg of seed, which is all that is needed for three years of official trials, and the 20 tonnes of seed of a market leading variety such as TRINITA delivered to farms this year.

Here are some of the other important issues worth considering in selection of conventional, Rhizomania-resistant and double-tolerant (BCN + Rhizomania) varieties:

The current Recommended List of sugar beet varieties is based on a limited number of trials.  Differences in yield figures of less than 3 % should be treated with caution. The effects of other factors on your farm, especially the time of drilling, the quality of the seed bed and the ongoing agronomy of the crop can lead to differences of 10-20% or more in eventual yield, more than twice the difference of the full range of the Recommended List .

  • Bolting: The threat of serious bolting is always there. Varieties with good resistance to bolting are essential to unlock the flexibility and yield benefits of early drilling. Being able to drill sugar beet as early as conditions allow can make a difference of 10% or more to the eventual yield - a much greater difference than that between varieties on the Recommended List. SARACEN, TRINITA and OPTA all offer excellent bolting resistance, while SENTINEL is the best of the Rhizomania resistant varieties.
  • Dirt & crown tare: All our current varieties have an improved root shape, with a shallower groove that retains less soil, and a biologically smaller crown.  This makes for easier, cleaner harvesting and lower dirt and crown tares.  These features put more beet on every load leaving the farm - particularly significant for those at a greater distance from the factory.
  • Large tops: Gaining a good canopy as quickly as possible is essential in the development of any sugar beet crop. Maximum light interception is key to the developing plant and helps build a robust crop with a high yield potential. A good canopy can also reduce weed growth and conserve moisture in the early stages of the crop and protect from cold and frost as the crop matures towards harvest. All Syngenta sugar beet varieties have large, or very large, tops and vigorous growth and are especially noted for canopy development and ground cover. At the BBRO Open Days this year, the Syngenta conventional varieties time after time showed the best canopy development and ground cover. Our varieties show good establishment and vigorous, early growth to provide good ground cover, rapid canopy expansion and the maximum opportunity for intercepting sunlight. Large healthy tops also help to protect later lifted crops from frost. SARACEN and TRINITA are particularly good for large tops.

Following crops: Your plan as to what will follow your sugar beet could well have an impact on your variety choice.  For many growers, ensuring that a field can be cleared, prepared and drilled with winter cereals in ideal conditions is an important factor. A beet variety with early maturity can help you to take this opportunity and may help in giving you more wheat yield. OPTA is a conventional variety well-suited to early lifting , whilst AIMANTA has a genetic early maturity and is ideal for the first 6 weeks of harvest.

Conventional Varieties

In the absence of Rhizomania, the ideal combination of attributes for a successful sugar beet variety is high yield, high sugar and low bolting.

And it still important not to underestimate the importance of bolting. The ability to drill as early as conditions allow can make a big difference - up to 10% - to the eventual yield, more than the difference in Adjusted Tonnes between all the varieties on the Recommended List

Good bolting resistance allows you to drill with confidence in the first weeks of March. If that drilling window is missed, conditions may not come right for another few weeks and later drilled beet may never make the crop of the earlier drilled beet.

TRINITA, SARACEN and OPTA offer the lowest susceptibility to bolting among the conventional varieties: SENTINEL the lowest among the Rhizomia-resistant varieties.

Numerous growers of TRINITA and OPTA obtained record yields of beet, many over 100 tonnes/ha, in 2009, and are looking forward to strong performances again this season.

Rhizomania resistance and an extra tonne of wheat

What follows the beet crop is not often an issue in variety selection.  However, growers who are drilling cereals after beet, particularly on heavy land, are keen to get a good crop of beet lifted early so they can be sure of time to get a good seed bed prepared.

When you consider that the optimum seed bed can make a difference of a tonne of wheat per hectare in the following crop, you can see why AIMANTA has attracted considerable interest.

AIMANTA is an early-maturing Rhizomania-resistant sugar beet that will give profitable yields from crops lifted at the beginning of the campaign. Its yields exceeded those of many of the top rhizo-resistant varieties in 2009.

The affordable answer to Beet Cyst Nematode

We are in the early years of a genetic solution to BCN. The first tolerant variety was launched this season. Whenever a new trait such as this is introduced it usually takes a few years of breeding work to bring yields up to those of conventional varieties.

SENTINEL virtually eliminates this 'yield drag', delivering yields within 1% of the mean of the Recommended varieties.  This an important benefit since nematode infestations occur in patches that are not always easy to map. SENTINEL delivers good yields on both infected and uninfected parts of the field.

In infected conditions, SENTINEL has shown a yield response of between 10 and 85%, depending on the level of infestation. SENTINEL also has the lowest susceptibility to bolting of any rhizo-resistant variety, making it easier to gain the yield advantage from early drilling.

The BCN problem

There is no reliable indication of the extent of BCN infestations in the UK beet growing areas, although BBRO are undertaking a comprehensive survey this year.  Low level infestations may not be visible but can depress yield by 10%.

In Sweden, Nordic Beet Research has tested all available varieties under infected and uninfected conditions.  Some 30% of the growing area is above the recommended threshold of 1 egg or larva per gram of soil. Some 45% of the crop is now in double tolerant varieties.  The Syngenta variety NEXUS, which is similar to SENTINEL has 32% of the overall market.

For more information about recognising and dealing with BCN, download our booklet by clicking here