INDEPENDENT agronomist Andy Alexander is again advising growers to opt for Compass oilseed rape after assessed winter rape varieties.Mr Alexander assessed Compass from DSV alongside fellow hybrid Excalibur from Dekalb. Both were direct drilled and at identical low seed rates on similar soils, he said.
“Using low seed rates allows the plant to express itself more fully and it gives me the chance to monitor plant structure in detail in order to understand where yield is being built.
“Both crops were monitored in detail throughout the season. At harvest I found that Compass performed much better when it came to yield, yielding 5.2 t/ha compared with Excalibur’s 4.7 t/ha. Both varieties delivered good oil content.”
After analysing the results of this yield performance, the most obvious reason was that the Compass produced 24 seed heads per branch, compared with Excalibur’s 20 seed heads – 17% more.
“Consistently Compass had more flowers and more seed heads per branch and more lower down the stem. This characteristic appears to be an intrinsic part of the variety and is a highly valuable feature for pursuing high yields.”
Although Compass was slow coming out of the very cold winter, it flourished in the spring and appeared to be able to avoid pigeon damage to a good extent. At the end of the season, however, both varieties matured at the same time.
“I have been very impressed by the all-round performance of Compass,” said Mr Alexander. “This is based on just one seasons’ work, which I intend to repeat, but on the data so far, I will advising my growers to grow it again this year.”