Limagrain is at the forefront of bringing varieties to market that are able to better withstand seasonal yield variability by ‘bundling’ genetic traits – and this is the very latest development to come out of this approach, explains Dr Vasilis Gegas, Limagrain’s European oilseed rape portfolio manager.
The first commercially available variety containing this trait is Ambassador, the highest yielding hybrid on the 2020-2021 AHDB Recommended List. New candidate variety, LG Aviron, also has the nitrogen efficiency trait, N-FLEX.
“We know that yield variability in oilseed rape is a challenge on farm – that is the difference between the genetic yield potential of the variety and what’s in the trailer at harvest.”
“One of the key challenges in meeting yield potential in oilseed rape is the way that the plant utilises nitrogen and the difficulty in achieving optimal N; there are many factors that influence this as OSR has a yield potential that’s set not just by its genetics, but also the parameters of its site.”
“Soil structure, biology and weather conditions lead to leaching and low solubilisation or mineralisation. Rotations and cover cropping also affect nitrogen levels, and of course legislative guidelines dictate how much can be used and where.”
Our challenge was to look at how we could use genetics to cope with these ambiguities and introduce varieties that would be able to maintain high yields in lower than ideal nitrogen conditions by optimising every unit of available nitrogen.
“For OSR the key factor is nitrogen use efficiency – this is how well a plant assimilates and mobilises nitrogen from the soil moving it up into the pods and ultimately the seed.”
“A high yielding oilseed rape variety has to mobilise a lot of N during pod fill. Too little and pods don’t develop and fill, too much and it can kill off the canopy.”
We have focused on how OSR moves plant protein from the stems, leaves and pods into the seed- transforming N into yield – this is the basis of the N-Flex trait.
Hybrids containing the trait use each unit of available N more efficiently than those which don’t have the trait. In the field, this translates into varieties with the N-Flex trait producing more stable yields year to year, with less in field yield variability.
This claim is backed up by a series of trials across Europe conducted by Limagrain, where leading varieties including Ambassador were given optimal, medium and high N-stress.
In all three scenario’s, Ambassador containing the N-Flex trait, was able to maintain its yields over and above varieties that did not contain the N Flex trait.
Source: Limagrain Europe; Three years’ trials (2017-19) at 15 locations in France, UK, Germany, and Hungary; Comparisons – average of Optimal N calculated by N balance method; Medium N stress had N reduced by 50-80 kgN/ha; High N stress had N reduced by 80-130 kgN/ha.