A ProMED-mail post <http://www.promedmail.org>
ProMED-mail is a program of the International Society for Infectious Diseases <http://www.isid.org>
In this posting:
 Germany (Bavaria)
 Indonesia: 1st rep (Java)
 Germany (Bavaria)
Date: Mon 13 Jan 2020
Source: Top Agrar [in German, trans. & summ. Mod.DHA, edited] <https://www.topagrar.com/acker/news/neues-gurken-virus-setzt-sich-in-deutschland-fest-11952499.html>
_Cucurbit aphid-borne yellows virus_ (CABYV) was recently identified in Bavaria (ProMED-mail post http://promedmail.org/post/20191217.6846213). But according to the Leibniz Institute, crops in Bavaria were already infected with the virus early in 2019 when farmers had complained about huge crop losses of up to 50 percent, attributed to an undiagnosed disease. A disease incidence of up to 90 percent had been observed.
CABYV is spread by aphids and is present in the Mediterranean region.
Scientists fear that the occurrence in Germany is only the beginning of a spread throughout central Europe, supported by more favourable conditions for the vector insects to survive increasingly warmer winters. The virus has now also been detected in Slovakia and Poland.
[Byline: Alfons Deter]
Castleview English Longhorns
Gut Laach, D-52385 Nideggen
 Indonesia: 1st rep (Java)
Date: Thu 9 Jan 2020
Source: Journal of General Plant Pathology [edited] <https://link.springer.com/article/10.1007/s10327-019-00905-2>
[ref: L Listihani et al (2020): First report of cucurbit aphid-borne yellows virus on cucumber in Java, Indonesia. J Gen Plant Pathol, First Online; doi: 10.1007/s10327-019-00905-2]
Since its initial description, _Cucurbit aphid-borne yellows virus_
(CABYV) has been reported to infect cucurbits in progressively more countries, and it was recently reported to infect faba bean in Turkey.
Chlorosis and yellowing with green-vein banding on older leaves were observed in surveys of cultivated cucumber fields in 2016 in Java, Indonesia. Initial dot immuno-binding assays detected 7 different viruses varying in frequency among over 500 samples from 27 locations.
CABYV was detected at a frequency approaching 100% in 4 provinces in Java. The coat protein nucleotide and amino acid sequences of 4 isolates had highest identity with that of CABYV isolate Aileu in East Timor, indicating that the outbreak and rapid expansion of CABYV throughout the world may involve host and vector abundance and geographical distance.
This is the 1st report of CABYV infection of cucumber in Indonesia [and] the 1st report that a major cause of cucurbit viral diseases in Java is CABYV. Other cucurbit and host species need to be surveyed for CABYV and coinfection with other viruses in the future to identify natural sources of the virus and to develop appropriate strategies to control the disease.
Communicated by: ProMED-mail <email@example.com>
[_Cucurbit aphid-borne yellows virus_ (CABYV; genus _Polerovirus_,
Luteoviridae) affects primarily cucurbit crops (such as cucumber, zucchini, melons, pumpkins, squashes), but has also been reported from lettuce and beet. Symptoms may be confused with nutritional problems and vary with crops, cultivars and environmental conditions. They may include interveinal yellowing, thickening and brittleness of leaves, complete yellowing of whole plants and loss of plant vigour leading to reduced flowering and fruit production. Yield losses of up to 50 percent for cucumbers and 15 percent for melons have been reported.
The virus resides in phloem tissue and can be spread by several aphid species in a persistent manner. Different aphid species vary in their efficiency of CABYV transmission, with _Aphis gossypii_ being one of the most efficient. Infectious insects can be spread with plant material or carried on air currents for long distances. The virus cannot be transmitted mechanically or by seed. Weed species serve as pathogen reservoirs. Disease management of aphid transmitted viruses is difficult and may include vector control, removal of virus reservoirs, phytosanitation and cultural measures (such as barrier plantings).
The currently known luteoviruses are mostly important crop pathogens and include _Potato leafroll virus_, _Turnip yellows virus_, _Maize yellow mosaic virus_, and several barley yellow dwarf viruses (see previous ProMED-mail posts in the archives).
<http://healthmap.org/promed/p/3744> and <http://www.lib.utexas.edu/maps/europe/germany.jpg> (with states) Europe, overview:
CABYV symptoms on cucurbits:
Additional news stories:
<https://idw-online.de/en/news729656> (in German) and <https://innovationorigins.com/dangerous-cucumber-cabyv-virus-is-spreading-to-northern-europe/>
Information on CABYV:
First report of CABYV in Germany:
Virus taxonomy via:
Information and taxonomy for aphid vectors:
Cucurbit aphid-borne yellows virus - Germany: (BY)
Cucurbit aphid-borne yellows virus - Iran: 1st Report
Cucurbit aphid-borne yellows virus - Tunisia
Cucurbit virus diseases - Sudan
Cucurbit aphid-borne yellows virus - Spain (Murcia)
and additional items on poleroviruses in the archives]