IN THE FLESH
CEREALS 95 will provide many oilseed rape growers with their first chance to see the latest recommended winter varieties, says NIABs oilseeds specialist Simon Kightley.
All three, which joined the list with a provisional tag last autumn, should be available commercially for next seasons sowings. Their main competitor is likely to be Apex, says Mr Kightley. "Seed statistics suggest it accounted for 43-44% of this years crop."
For a detailed insight into the full potential of all varieties, including spring types, he advises a read of the Oilseeds Variety Handbook*, which includes regional yield results. The latest edition contains a financial evaluation of the benefits of fungicides on winter rape. It also has sections on turnip rape, linseed, sunflowers, evening primrose and borage.
Nickel, from CPB Twyford, the highest yielder of the trio has been in NIAB trials for two years compared with Apexs four. Yields were identical in treated plots. But Nickels untreated output (11% above Apex) last year, when light leaf spot was dominant, is "particularly interesting". "You have to be wary of one years results, but its yield was significantly better."
The downside is that in strong winds during flowering in 1993 Nickel was "noticeably susceptible to lodging". This is reflected in a recommended list note that it is not entirely suitable for heavy land. "Last year it escaped completely – there was no serious lodging in any NIAB trials." Care may be needed not to sow it too thickly, adds Mr Kightley.
Amber, Apexs stable-mate from Zeneca, is slightly taller and later than other recommended varieties, which could limit its potential in the north. But because of its canopy structure and moderately good standing ability it is easily managed. "It is not likely to become a tangled mess," says Mr Kightley.
In treated yields it was only 1% below Apex. Like Nickel it has a provisional light leaf spot resistance rating of 9, which probably accounts for its good performance in untreated trials last season. Oil content at 45.1% is also higher than average (44.2%).
Commanche, from CPB Twyford, is provisionally recommended for the northern region where it "shared top spot" for yield in treated trials with Nickel. "But it has much better standing ability and it is earlier, which is significant in the north." Elsewhere treated and untreated yield have been "moderate".
Commanche merits an 8 for light leaf spot resistance and has the second highest oil content of the listed varieties at 45.2% (Express is best for oil at 45.6%).
* The 56-page booklet costs £8 incl p & p.