Spring forward for OSR hybrid vigour growth
Hybrid vigour has once again proven hugely important to bring on backward oilseed rape crops, after the late start to spring this season.
In Berkshire, Sutton Estates’ Farm Manager and iOSR grower, Joe Dilibero (below, spraying a late flower application in OSR), has seen his hybrid varieties rocket from below knee to above shoulder, in just six weeks growing. What has been especially pleasing is the side branches and main raceme all growing together – so flowering has been really condensed and the crop is setting pods evenly.
“We got good establishment in the autumn, with plant counts typically between 25 and 35 plants per m2,” he reported. “Although we sowed the same 45 seeds m2, overwinter populations were possibly lower than in the past, but was very even across most of the fields. Fortunately, pigeons were not much of a problem.
“What it has meant is that plants have had plenty of space to grow. The result has been incredible, with branching from low down and really strong growth.”
Even the crops growing on light soils over gravel have rocketed through spring growth, boosted by chicken manure in the autumn seedbed.
“It all looks really healthy and good leaf canopy, with only minimal fungicide inputs and fertiliser, apart from some extra Boron,” pointed out Joe. The quick and even flowering has also aided flowering spray application timing (below), with low sclerotinia risk in the dry weather and a greater focus on later diseases and healthy leaf retention,
Flowering this season was at least three weeks behind last year to start, he recalled, but the hybrids have all flowered remarkably quickly. The bulk of the crop was set to complete flowering in just 10 to 14 days; pod set (below) also looked to have been extremely good, he added.
A second consecutive season of prolonged winter conditions and delayed spring growth has reinforced the benefit of spring hybrid vigour, highlighted Syngenta OSR Seed Manager, Mark Bullen.
“Strong early emergence is crucial to get the crop up and growing, but once again we have seen very forward autumn crops go backwards in late winter,” recalled Mark (below).
“Establishment appears more about sowing date and conditions, rather than hybrid or conventional genetics,” he told iOSR growers.
“Varieties that use their hybrid vigour to kick start early spring growth, such as the new SY Iowa and George, have the chance to really grow away as soon as conditions allow.”
That early vigour has been especially important this year, to rapidly build the green leaf canopy that will enable crops to perform better in the relatively short growing season. That's been even more evident when allied to agronomic techniques advocated by most iOSR growers, such as split and later application of spring nutrition, PGR canopy manipulation and later Amistar treatments to retain green leaf for longer.
Mark pointed out that SY Iowa had good resistance to Light Leaf Spot and an excellent rating for Phoma. Its yield was delivered through a high number of pods, now recognised by YEN as essential to generate high output, as well as good resistance to pod shatter that ensured more seed could be safely harvested, as well as reduce the potential issues of volunteer seed return seen with conventional varieties.