March 18, 2022

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: February 2022
Source: European Plant Protection Organisation (EPPO) Reporting Service 02/2022/043 [summ. Mod.DHA, edited]
https://gd.eppo.int/reporting/article-7273

Cucurbit chlorotic yellows virus (CCYV) is transmitted by whiteflies It was first identified in 2004 causing damage to melon (_Cucumis melo_), watermelon (_Citrullus lanatus_) and cucumber (_Cucumis sativus_) crops in China, Japan and Taiwan (EPPO RS 2011/007). It then spread to Africa (RS 2012/038) and the Middle East (RS 2015/119).

It has recently been reported from several countries in the EPPO region: Greece (Islands of Rhodos and Kriti) in 2014; Turkey in 2015; Israel in 2016; Algeria in 2018 (RS 2020/048); Spain in 2018 (RS 2021/166) and recently in watermelon and courgette (_Cucurbita pepo_) on Tenerife Island.

In the Americas, it has been reported from the USA in 2018 and in additional areas in 2021 in melon, watermelon and courgette (squash).

In Asia in 2021, it was reported from the Philippines (RS 2021/185), South Korea in melon (_Cucumis melo_ and _C. melo_ var. _makuwa_) and cucumber, and from India in pumpkin (_Cucurbita moschata_).

--
Communicated by:
ProMED

[Cucurbit chlorotic yellows virus (CCYV) has not yet been approved as a taxonomic species due to its as yet incomplete or unverified sequence information. It is still designated as an unclassified virus related to genus _Crinivirus_ by the International Committee on Taxonomy of Viruses (ICTV; see links below).

The whitefly species _Bemisia tabaci_ has so far been shown to be a vector of CCYV; further work is needed to assess other potential whitefly vectors. Both cucurbit species (Cucurbitaceae) and species in other families have been reported as natural or experimental hosts, including some wild species which may serve as virus or vector reservoirs for infection of crops.

CCYV symptoms on cucurbits include brittleness, thickening and interveinal yellowing of leaves, often resembling nutritional deficiencies. Similar symptoms in crops can also be caused by _Crinivirus_ species such as _Cucurbit yellow stunting disorder virus_, _Beet pseudoyellows virus_; or by _Polerovirus_ species such as _Cucurbit aphid-borne yellows virus_ and _Pepo aphid-borne yellows virus_.

Criniviruses are transmitted exclusively by their insect vectors, they cannot be spread with seed or by mechanical means. Outbreaks are usually associated with high vector populations. Weed hosts may serve as virus and/or vector reservoirs. Control of whitefly  transmitted viruses is particularly difficult in open field crops due to the widespread presence and wide host range of whiteflies. Disease management of these viruses is difficult and includes vector control, removal of reservoirs of both virus and vectors, use of crop varieties with increased pathogen tolerance, and clean planting material.

Pictures
CCYV symptoms on cucurbit leaves:
https://bugwoodcloud.org/images/1536x1024/5556501.jpg,
https://bugwoodcloud.org/images/768x512/5556502.jpg and
https://bugwoodcloud.org/images/768x512/5556503.jpg
Whiteflies:
https://www.planetnatural.com/wp-content/uploads/2012/12/whitefly.jpg
and
https://www.pinpointpestcontrol.com/images/whitefly-on-plant.jpg

Links
Information on CCYV and characterisation:
https://gd.eppo.int/taxon/CCYV00,
https://www.cabi.org/isc/datasheet/110472,
https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&id=558690,
https://doi.org/10.1094/PDIS-02-17-0164-RE, via
https://doi.org/10.1016/B978-0-12-816030-5.00012-4 and
https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/cucurbit-chlorotic-yellows-virus
CCYV transmission by _B. tabaci_ vector:
https://doi.org/10.1016/j.jviromet.2015.04.014 and
https://doi.org/10.1038/srep36604
Description of genus _Crinivirus_:
https://talk.ictvonline.org/ictv-reports/ictv_online_report/positive-sense-rna-viruses/w/closteroviridae/1293/genus-crinivirus
Virus taxonomy via:
https://talk.ictvonline.org/taxonomy/
Information on whitefly vectors:

http://www.ipm.ucdavis.edu/PMG/r783301211.html and
http://www.issg.org/database/species/ecology.asp?fr=1&si=106
- Mod.DHA]

[See Also:
2021
----
Lettuce infectious yellows virus - Europe: 1st rep (Spain)
http://promedmail.org/post/20210820.8608396
Multiple viruses, tomato - India: (MH)
http://promedmail.org/post/20210705.8495612
2020
----
Tomato chlorosis virus: 1st reports, new hosts
http://promedmail.org/post/20200607.7428940
2018
----
Tomato chlorosis virus - Netherlands
http://promedmail.org/post/20180719.5914214
2017
----
Cucurbit yellow stunting disorder virus - Italy: 1st rep (Sardinia)
http://promedmail.org/post/20170111.4753360
2015
----
Vegetable viruses - Spain: (AN) alert
http://promedmail.org/post/20151204.3839034
and additional items on criniviruses in the archives]

Website: http://www.isid.org

Published: March 21, 2022