A ProMED-mail post <http://www.promedmail.org>
ProMED-mail is a program of the International Society for Infectious Diseases <http://www.isid.org>
Date: Fri 8 Mar 2019
Source: Farmers Weekly [edited]
<https://www.fwi.co.uk/arable/sugar-beet/virus-yellows-warning-for-beet-growers-after-mild-winter-and-loss-of-neonics>
Sugar beet crops are at high risk from virus yellows this summer [2019] because of higher aphid populations arising from the mild winter. Virus yellows is a largely forgotten disease carried by aphids that for many years has been well controlled by the routine use of neonicotinoid seed treatments. However, this coming season [2019] is the 1st time in 25 years that these treatments are not available to protect the crop from aphids, leaving beet vulnerable to the disease.
In northern France in 2017, the French sugar beet growers association reported heavy (25%) infection with virus yellows when neonicotinoid seed treatments were not used. This resulted in a 36% reduction in sugar yield in infected patches.
The British Beet Research Organisation (BBRO) has produced disease forecasts and in the worst-case scenario, it predicts more than 50% infection. However, they point out that the risk can be reduced by a timely application of aphidicide, along with good crop hygiene, monitoring and ensuring crops reach the 12-leaf stage as quickly as possible.
[byline: Richard Allison]
--
communicated by: ProMED-mail <promed@promedmail.org>
[Virus yellows is an important disease affecting yield in sugar beet in the UK and elsewhere. The beet yellows complex may include one or several viruses. In the UK, the main viruses involved are _Beet yellows virus_ (BYV; genus _Closterovirus_), _Beet mild yellowing virus_ (BMYV; genus _Polerovirus_) and _Beet chlorosis virus_ (BChV; genus _Polerovirus_). These viruses are transmitted by aphids, including the peach aphid (_Myzus persicae_). Disease management usually includes phytosanitation as well as vector control by field applications and seed treatments with insecticides. Resistance breeding for multiple pathogens is difficult because host susceptibility is likely to involve different genes for the different pathogens.
In the UK, the disease had already been considered a re-emerging threat even with 90% of the crop receiving an effective
(neonicotinoid) seed treatment (ProMED-mail post http://promedmail.org/post/20100220.0582). Banning of neonicotinoids, the emergence of vector resistances to some foliar insecticides, as well as the warming climate favouring an increase in aphid numbers, suggest that integrated management strategies will be required in the future to control the disease.
Maps
UK:
<http://www.lib.utexas.edu/maps/europe/united_kingdom.gif> (with
counties)
Pictures
Sugar beet virus yellows leaf symptoms:
<https://cropscience.bayer.co.uk/media/102725813/virus-yellows-beet-1200.jpg>,
<http://www.inra.fr/hyp3/images/6030601.jpg> and <https://c8.alamy.com/comp/APFJJ7/sugar-beet-virus-yellows-sbvy-infection-on-mature-sugar-beet-plant-APFJJ7.jpg>
Sugar beet field affected by virus yellows:
<https://bmcontent.affino.com/AcuCustom/Sitename/DAM/147/050517_p12_13_BB_Virus_yellows_Main.jpg>
and
<https://c8.alamy.com/comp/X9TB4J/sugar-beet-virus-yellows-foci-of-infection-in-a-sugar-beet-crop-X9TB4J.jpg>
Aphids:
<https://d1o50x50snmhul.cloudfront.net/wp-content/uploads/2013/11/dn24513-1_800.jpg>
Links
Additional news story:
<https://www.fwi.co.uk/arable/crop-management/pests/tips-on-growing-beet-without-neonic-seed-treatments>
and
<https://www.fginsight.com/news/news/beet-growers-alerted-to-virus-yellows-threat-in-new-season-crop-79395>
Information on sugar beet virus yellows:
<https://cropscience.bayer.co.uk/threats/diseases/sugar-beet-diseases/virus-yellows-beet/>,
<http://www7.inra.fr/hyp3/pathogene/6beyevi.htm>,
<https://www.bcpc.org/wp-content/uploads/2018/10/5-s-Mark-Stevens.pdf>,
<https://www.researchgate.net/publication/8449937_Decision_making_in_controlling_virus_yellows_of_sugar_beet_in_the_UK>
and
<https://naldc.nal.usda.gov/download/CAT87201161/PDF>
Virus taxonomy via:
<https://talk.ictvonline.org/taxonomy/>
Information on aphid vectors via:
<http://www.cals.ncsu.edu/course/ent425/text18/plantvectors.html>
British Beet Research Organisation:
<http://www.bbro.co.uk/>. - Mod.DHA]
[See Also:
2010
---
Rhizomania, virus yellows, sugarbeet - UK: new strain
http://promedmail.org/post/20100220.0582
2007
---
Beet and cucurbit viruses, multiple hosts - China: 1st reports
http://promedmail.org/post/20070516.1564
2005
---
Beet yellow vein virus, sugarbeet - Morocco: 1st report
http://promedmail.org/post/20051112.3310
2002
---
Beet necrotic yellow vein, sugar beet - UK (England)
http://promedmail.org/post/20020827.5164
Beet viruses, sugar beet - Syria
http://promedmail.org/post/20021218.6089
and additional items on beet viruses in the archives]
Topics
Species
