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: Mon 13 Nov 2017
Source: HortiDaily [edited]
<http://www.hortidaily.com/article/39132/Spain-New-Delhi-virus-reduces-and-delays-courgette-production>
The courgette [zucchini] season is developing in Almeria [Andalusia] with a lower production that was marked by the impact of the New Delhi virus. "The New Delhi virus has caused a delay in the harvest [and] is limiting the courgette production. This year [2017], there will be a lower production compared to previous years," says the Almeria-based company Escobi [which] handles a volume of around 20 million kilos [about 44 million lb] of courgettes. The demand for courgettes is on the rise.
--
Communicated by: ProMED-mail <promed@promedmail.org>
[_Tomato leaf curl New Delhi virus_ (ToLCNDV; genus _Begomovirus_) has been reported to cause severe yield losses on tomato and watermelon crops on the Indian subcontinent. It belongs to the tomato leaf curl and yellow leaf curl clades of the genus. Known species in these clades cause similar diseases on solanaceous and other crops and can lead to considerable yield losses. Begomoviruses are transmitted by different whitefly vectors (such as _Bemisia tabaci_ biotypes), and many can also be transmitted by mechanical means and grafting, but they are not seed transmitted.
Whiteflies in themselves are serious pests of many vegetable crops. If virus sources are available locally, high vector numbers are often reflected in high levels of the viral diseases they transmit.
Begomovirus control is particularly difficult in open field crops due to the widespread presence and wide host range of whiteflies. Disease management may include pathogen exclusion, vector control, as well as elimination of possible pathogen and/or vector reservoir plants. In some cases, crop cultivars with increased virus resistance are available.
ToLCNDV was limited to Asia until it was reported from Europe for the 1st time in 2013 on cucurbits in Spain (ProMED-mail post http://promedmail.org/post/20131223.2131729). It has since also been reported from Italy (ProMED-mail post
http://promedmail.org/post/20160327.4121164) and Tunisia and was included in the EPPO alert list. ToLCNDV has a wider host range than the related _Tomato yellow leaf curl virus_, which had previously been present in the region.
The source of the Mediterranean incursion so far remains unknown.
Recent research (see link below) has shown that a novel recombinant strain causes the severe damage to cucurbit crops in the region, but poorly infects tomatoes. In Spain, a genetically uniform virus population was identified which would be compatible with a recent introduction. Major concerns in the region are a continued spread, both geographically and in host range, and the potential of coinfections with other begomoviruses already present which may lead to synergistic enhancement of symptoms as well as emergence of further strains due to additional recombination events.
Maps
Spain:
<https://www.ezilon.com/maps/images/europe/political-map-of-Spain.gif>
and
<http://healthmap.org/promed/p/6672>
Provinces of Spain:
<http://www.venamicasa.com/wp-content/uploads/2012/03/spain_map3.gif>
Pictures
ToLCNDV symptoms:
<http://cienciacebas.files.wordpress.com/2013/09/aranda-1.jpg>
(zucchini) and
<http://cienciacebas.files.wordpress.com/2013/09/aranda-2.jpg>
(cucumber and melon)
Photo gallery of symptoms of different begomoviruses:
<http://www.forestryimages.org/browse/TaxImages.cfm?fam=651&genus=Begomovirus>
Links
Information on ToLCNDV:
<https://www.eppo.int/QUARANTINE/Alert_List/viruses/ToLCNDV.htm>
Information on leaf curl viral diseases on different hosts:
<http://www.oisat.org/pests/diseases/viral/leaf_curl__virus.html> and <http://www.daff.qld.gov.au/plants/health-pests-diseases/a-z-significant/tomato-leaf-curl-virus>
Characterisation of recombinant ToLCNDV strain in the Mediterranean
region:
<https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5127021/>
ToLCNDV taxonomy & current species list of the clade via:
<https://talk.ictvonline.org/taxonomy/>
EPPO quarantine alert list:
<https://www.eppo.int/QUARANTINE/Alert_List/alert_list.htm>
Escobi:
<http://www.escobi.es>
- Mod.DHA]
[See Also:
2016
----
Vegetable viruses - Jamaica
http://promedmail.org/post/20160421.4173419
Tomato leaf curl virus, eggplant - India: (TN)
http://promedmail.org/post/20160415.4160915
Tomato leaf curl New Delhi virus, cucurbits - Italy: 1st rep (SC)
http://promedmail.org/post/20160327.4121164
2015
----
Vegetable viruses - Spain: (AN) alert
http://promedmail.org/post/20151204.3839034
2014
----
Tomato yellow leaf curl virus - Ghana: (TV)
http://promedmail.org/post/20140717.2616753
Tomato leaf curl New Delhi virus - Spain: (AN) alert
http://promedmail.org/post/20140321.2345942
2013
----
Tomato leaf curl New Delhi virus, zucchini - Spain: (MU) 1st report
http://promedmail.org/post/20131223.2131729
Yellow leaf curl & blights, tomato - Pakistan: (SD)
http://promedmail.org/post/20130206.1531086
2011
----
Vegetable viruses - Australia: (WA, QL)
http://promedmail.org/post/20110314.0817
Tomato yellow leaf curl, cowpea - China: new host, (SH)
http://promedmail.org/post/20110121.0244
2010
----
Tomato yellow leaf curl virus - Spain: (AL)
http://promedmail.org/post/20100923.3444
and older items in the archives]
Topics
Species
