With the introduction of CDC Maxim, CDC Impala and CDC Impress, lentil growers officially have a Clearfield variety in each class, with several new varieties in the pipeline. CDC Maxim is a small red lentil that yields 101 per cent of CDC Milestone. CDC Impala is an extra small red that yields 92 per cent of Milestone. And CDC Impress is medium green, yielding 94 per cent of Milestone.
In three growing seasons Clearfield varieties have gone from zero to the majority of red varieties planted and a good portion of green varieties, too. Mark Kuchuran, Sr., technical development specialist with BASF Canada, says that farmers’ adoption of the new varieties has been stellar. “We’re estimating 10 per cent of the large green crop and 60 per cent of all reds were Clearfield varieties in 2009,” he says.
The quick uptake and widespread adoption of the new varieties is understandable given that the Clearfield trait offers expanded in-crop weed control options that won’t knock back the crop.
“The biggest value really is that you’re spraying once, and there is no herbicide injury to the crop, unlike past options,” Kuchuran says. Clearfield varieties are tolerant to imidazolinone, thus the im in most new variety names, and as such can be sprayed with Odyssey DLX, Odyssey and Solo without risk of injury or crop setback. “After the first application, depending on the year, you may still have to go in to control volunteer cereals or wild oats, or for a fungicide application, such as Headline, for further yield protection,” he says.
Timing of spraying is also somewhat more flexible. “On conventional fields, you’re looking at going in when the crop is roughly four inches high. The five-node stage is the optimal staging with Clearfield varieties, but with the late spring and slow growing conditions this year, we went in as late as the seven-to 10-node stage and still had no crop injury,” he says. Waiting that long always carries a risk of the weeds being too large to get good control, however, and isn’t recommended. “Still, in a year like we just had, it bought us a bit of time,” he says.
The fact that this spraying advantage comes through conventional and not genetically modified means is also a plus. “We’ve discussed market access with processors and have been told there are no issues with Clearfield varieties. In fact we’ve been told they’re plumper seeds in some cases,” he says. Growers like the system because samples are usually cleaner with far less dockage.
Cleaner fields translate into higher yields, too. Kuchuran says grower trial plots comparing Clearfield varieties to conventional show a two bushel per acre yield gain on reds and a three-bushel gain on greens.
Bert Vandenberg at the University of Saskatchewan’s Crop Development Centre has four new varieties going into seed production for 2010. To round out farmers’ options, three new green varieties, one red and one niche market French variety are moving forward in the registration queue.
Vandenberg says that with advanced breeding techniques, incorporating the Clearfield trait into new varieties is not that difficult. “We can develop a new variety in five years,” he says. He adds that the pipeline is progressing and growers can look forward to new and improved Clearfield varieties in various classes for years to come.
Each class will eventually have several Clearfield choices. “Newer and better varieties will replace some of the first few out there,” he says.
While adoption of the varieties has been quick, Vandenberg says that farmers still need to be on the look out for weed resistance to the Clearfield weed control options. “Kochia and wild mustard with resistance to these chemicals is out there and a concern,” he says. Rotating modes of action and thinking about weed control in the fall and the spring, not just in crop, are necessary to manage weed resistance.
Lyndsey Smith is a field editor for Grainews. She lives in Lumsden, Sask.