DSV United Kingdom Ltd.

Troy - Semi Dwarf

 
Ideal combination of hybrid and low biomass features in rape
 
Several years ago low biomass or shorter varieties of oilseed rape were introduced to the UK market and caught the imagination of growers because of their ease of management and potential lower cost of production. These varieties were open-pollinated varieties. More recently hybrid rape varieties were launched and now dominate the sector due to their overall performance and crop vigour. It is only recently that the oilseed rape types - semi-dwarf and hybrid - have been brought together in the one variety type, offering growers a desirable combination of characteristics.
 
Colin Button, Seed Manager for national distributor HLHutchinson, reports that nationally between 60 and 65% of seed sales are hybrids. “For Hutchinsons this is even higher at over 80% of our seed sales. This is because hybrid rape offers both high performance and excellent vigour. Hybrids show better vigour at establishment, which is a very important time in the crops’ life, but also in the spring when the crop bounces back from the winter and starts to extend. It is a benefit that farmers can see easily for themselves in the field.”
 
Colin has noticed on their five variety trials sites, the hybrid rape variety Troy from DSV has shown positive vigour. “This variety is in the Candidate Recommended List trials this year and it has certainly looked the part. Not only can we plant a lower seed rate (40 – 45 seeds per sq m) being a hybrid, but its early vigour has been shown to be a benefit when it comes to competing with black-grass early on in the crops life, where the crop can be sown a little thicker (50 – 55 seeds per sq m) to ensure good ground cover and a suppression of black-grass and not run the risk of lodging as with higher seed rates of other normal height hybrids.”
    
Troy is one of the first hybrid semi-dwarf varieties, combining one of the highest yields of any semi-dwarf plus all the benefits of a hybrid. “Troy is consistently short at around 138 cms height, which means, as with semi-dwarf types, it is easier and cheaper to manage. Troy is also almost totally resistant to lodging. It has ratings of 8 for stem stiffness and an 8 for resistance to lodging.”
 
“One aspect we have noticed in trials is that although the semi-dwarfs are shorter in the aerial part of the plant, they still have a very strong and robust rooting system, so the dwarfing gene applies to above ground parts, not below,” comments Colin.
 
At harvest Colin Button reckons you can combine Troy twice as fast as some other taller varieties. “It will present well to the combine cutting table, with less pod shatter. It also ripens more evenly as there is no compression of pods from the top part of the canopy. I have noticed too that Troy appears to dry earlier in the morning and later in the evening due to its compact canopy structure. Overall growers have very worthwhile time advantages and measurable fuel savings. I anticipate that growers will like a lower biomass variety combined with hybrid vigour and that Troy will see good success in the market as a consequence.”
 
Semi-dwarf hybrids still perform well compared with taller hybrids. Troy, for example yields 107% with a good oil content of 44.8%, better than most other hybrids.
 
Colin Button advises that a variety such as Troy should be sown early and on high fertility sites to make the most of their advantages.
 
Sarah Lockhart of DSV says that Troy is the first semi-dwarf from DSV. “We already have an excellent range of hybrid rapes, but Troy is our first semi-dwarf and appears to represent a jump forward in this breeding technology, outperforming all the controls and the majority of varieties in trials. Being around 16 cms shorter than the hybrid Excalibur, it has all the management pluses associated with a low biomass variety and all the performance pluses of a hybrid.”