Hybrid oilseed rape varieties have demonstrated they can withstand extremes of weather and are on target to virtually match last year's harvest, according to Simon Meakin of Springdale Farms where for example Borneo demonstrated an exceptional 5.13t/ha to achieve a gross margin on £708/ha.
He says this season's crop growth and development has been 'absolutely astonishing' among the 60ha commercial field scale trial of hybrids sponsored by Syngenta Seeds at Springdale' Farm, Rudston, near Driffield. "The prolonged dry period earlier in the year led spring nitrogen uptake to be around four weeks later than normal. Subsequently plants are approximately 30cm shorter than usual, making the crop easier to manage when we come to swath," he explains. "Overall the crop has compensated well, it is exhibiting greater stem branching, and pod formation and fill, and there have been very few pod abortions. Also rooting is deeper than normal and these roots appear to have developed more lateral branching."
Until last season, a high input high output regime had been assumed to maximize hybrid winter oilseed rape returns. However the Springdale trial arrived at a clear cut conclusion following harvest 2002 that not all varieties require the same level of inputs to maximize yield and subsequent gross margin. See table 1 below which shows yield and financial results from just some of the input combinations.
"Spring nitrogen is usually the determining input when it comes to final yield. We found that two of the three varieties demonstrated a yield and cost benefit with high inputs of nitrogen. For example Borneo demonstrated an exceptional 5.13t/ha to achieve a gross margin on £708/ha," he explains. "However we also arrived at the surprising conclusion that Royal achieved optimum yield and gross margin with a moderate 170kgN/ha. Furthermore, the Royal response was consistent with results from previous years."
