Choosing the correct variety of Oil Seed Rape (OSR) makes a huge difference in what you are going to have to spend and ultimately what you are going have to sell.
Looking at the HGCA harvest results (t/ha yield) for 2021 – PRACTICALLY - varieties break in to three groups with 0.1 t/ha difference between each group. With such little difference surely it makes sense to choose a variety that is LOW COST to grow. That is seed as well as input costs are low as well as low risk of failure should the season go against us?
Firstly, does Hybrid Vigour exist?
Yes, increased vigour over either parent of a cross between two inbred lines has been frequently reported in plant breeding. It is usually explained, in Mendelian terminology, as the result of association of several genes for plant size which had been isolated in either parent and subsequently as a loss of vigour in succeeding generations is attributed to segregation.
However, the story does not stop there. Growth of biomass requires the ready availability of the major nutrients. Where this occurs, the biomass produced, when compared to untreated plants, can easily double.
Drilling early allows more time for nutrient access and accumulation into biomass, however it also predisposes plants to a number of costly ailments. Not only this but it allows the plant to pass through its growth stages earlier than perhaps it should once more predisposing it to further inconsistencies in potential yield when harvest occurs July 2022 (something else seen in the 2021 HGCA trials data!)
Hence drilling Winter Oil Seed rape in mid-summer is a long-term recipe for increased risk and cost per ha.