The BBRO has announced preliminary results from 2018 trials work to study the impact of virus yellows on 10 commercial sugar beet varieties. This trial was sown on 12th May 2018 and harvested in January 2019.
According to BBRO, every plant within the replicated plots was inoculated by hand with aphids, in early June, carrying either beet yellows virus (BYV) or beet mild yellowing virus (BMYV).
From this trial yield losses of up to 42 per cent and 20 per cent were recorded across varieties due to the infection with either BYV or BMYV respectively.
This confirms previous findings of the significance of these viruses on yield potential of sugar beet. The charts (below) show the relative performance of the varieties in 2018 infected with either BYV or BMYV.
Although 10 varieties were tested only those varieties commercially available in 2019 are presented below.
BBRO says that it would normally wait until it had more results than just one trial in one season before releasing any information, particularly as 2018 was an atypical season due to the wet March and summer drought.
However, in light of the potential virus yellows pressure forecast for 2019, it believed it should release some of these provisional data as it may help growers reflect on the order in which they drill varieties and harvest them.
It is important to note this data is from a BBRO research project and is not directly linked to the Recommended List, it adds.
BBRO says that it has not been able to test all commercial varieties to date and performance of most varieties on sale has yet to be determined.
Growers should note some infected varieties that had less visible damage to the foliage during the season were low yielding, while, on the other hand, some with damaged foliage were high yielding, points out BBRO.
The conclusion (albeit from one trial in one ‘unusual’ season) is that the state of the foliage of current varieties may not necessarily be an indicator of yield under virus infection. The organisation is still trying to understand this relationship and continues to work on this on behalf of the industry, it adds.
BBRO says it welcomes feedback of experiences in 2019. For the future, breeders are working to produce true tolerant/resistant varieties and are collaborating with BBRO to help develop these for the future, it concludes.