Top Yields From High Tillering Types– Despite Rust

According to KWS UK wheat breeder Mark Dodds, this year, high tillering types with strong grain-fill characteristics have top-performed, hanging on to eek the most out of the dull weather during maturity.

“In 2006, it was high temperatures at the end of grain-fill that adversely affected a lot of varieties,” he says. “This year, varieties such as Robigus and Oakley, which are capable of filling grain over a long period have been able to, and have reaped the benefits of a completely different, dull, damp summer.”

According to Mr Dodds, while the hot, dry April affected tillering in all varieties, the stronger tillering ones established more tillers and thereby dropped less during this period of stress. This provided a better platform for higher yields, which the better filling types were able to build on during grainfill.

“In 2006, in contrast, high tiller numbers proved to be a disadvantageous. In this season, wheats couldn’t find enough water to keep going. As a result it was varieties with thicker stems and lower tiller numbers, such as Humber and Einstein that produced higher yields.”

Mr Dodds points out that the dull weather during grainfill has also highlighted differences between a variety’s ability to produce bold grain. Typically fuller grained varieties such as Cordiale have also done well and this has helped the Group 2 variety close the yield gap on Einstein.”

KWS UK agronomist Simon Francis reckons that lower than normal yields were always on the cards following the particularly wet autumn. “Rooting was restricted and as a result many crops couldn’t source the nutrients needed during early spring and summer,” he says.

While he admits there were some problems in traditional rust hotspots, in general growers got on top of the disease in what was a high rust pressure season.

“In developing a market for Robigus, we have always highlighted its relatively poor susceptibility to yellow rust. But at the same time we have stressed that it is not like Brigadier and will still perform in a bad rust year.

“Trials by ADAS back in 2002 and 2003 where inoculated, untreated plots were completely swamped by rust show there are clear differences in a variety’s ability to cope with the disease. While yellow rust wiped 8t/ha off Brigadier’s yields, Robigus lost just 1t/ha, around 10% of its yield potential,” he says.

“This year the season conspired to produce high rust pressure, but at the end of the day, while yields are down, the additional benefits of Robigus in terms of its ability to retain green-leaf and repel septoria counteracted any set backs from rust.

Mr Francis says that right from day one, everything pointed towards a high rust pressure year. “We saw carry-over and rust infections in the autumn and then few significant frosts to reduce disease levels.

“The warm, wet start to the spring maintained inoculum at the bottom of the crop which then had the potential to develop strongly in the hot, dry April.

“These conditions coincided with an unfortunate breakdown in resistance to brown rust in many widely grown, popular varieties, including Alchemy, Robigus and Claire.

“While I suspect that many growers didn’t get a T0 onto these crops and had a difficult spring, trying to get T1s and T2s effectively applied, what they used worked and it is only in hotspots where significant rust escaped.

“Next year the rust risk is in place with susceptible varieties already in the ground,” he points out. “So, if early conditions again favour the disease, then it will pay to get in early, knock it out and keep it out as the year progresses.

“This will include the use of a T0 such as a low rate of Caddy, or Opus, Folicur or Tracker mixed with Bravo for Septoria. If eyespot is a key target, then Tracker or Proline will be the preferred options,” suggests Simon Francis.