Cucurbit Genetics Cooperative Report 8:76-77 (Article 29) 1985
Lack of Resistance to Zucchini Yellow Mosaic Virus in Accessions of
New York State Agricultural Experiment Station, Cornell University, Geneva, NY 14456
USDA Northeast Regional Plant Introduction Station, Geneva, NY 14456
Zucchini yellow mosaic virus (ZYMV) is one of the most destructive pathogens infecting cucurbits, and although of recent identification (1981), it is known to be present in 15 countries on five continents (1, 2, 3, 5). Epidemics have occurred in Europe, the Middle East, and in the United States and particularly devastated were melon (Cucumis melo) and summer squash (Cucurbita pepo) (1,5, 6). Efforts to find sources of resistance in accessions of C. pepo
have been unsuccessful, however, C. ecuadorensis
and an accession of C. moschata are resistant (1, 5).
The search for additional sources of resistance or tolerance to ZYMV in other Cucurbita
species has continued, and this report deals with the evaluation of the C. maxima
available at the USDA Northeast Regional Plant Introduction
Station, Geneva, New York. This collection comprises
418 accessions, of which
386 bear the Plant Introduction numbers (P.I.), and 32
the Geneva State numbers (G). These accessions were originally
collected in 35 countries
on six continents, and they are listed in the Northeast
Regional Plant Introduction Station Serial Publications
N° 24 (1975) and N° 24C
In screening for resistance to ZYMV, ten plants of each accession were mechanically inoculated at the first leaf stage with each of the two known strains of the virus present in the United States: ZYMV-CT and ZYMV-FL (5). Plants which failed to develop symptoms after the first inoculation were reinoculated with the pertinent strain. All tests were conducted in an insect-free greenhouse maintained at 25-30 C.
None of the 418 accessions tested was resistant or tolerant to either strain of ZYMV. All plants develop a persistent and rather prominent mosaic, foliar distortion and severe stunting.
Considering the number of lines involved, their origin and diversity, the lack of resistance or tolerance in C. maxima
is disappointing. However, some accessions of this species were demonstrated to be resistant or tolerant to other cucurbit viruses (4).
- Lecoq, H., M. Pitrat, and M. Clement. 1981. Identification et
caracterisation d'un potyvirus provoquant la maladie du rabougrissement
jaune du melon. Agronomie
- Lecoq, H., V. Lisa, and G. Dellavalle. 1983. Serological identity of
muskmelon yellow stunt and zucchini yellow mosaic viruses. Plant
- Lisa, V., G. Boccardo, G. D'Agostiono, G. Dellavalle, and M. D'Aquino.
1981. Characterization of a potyvirus that causes zucchini yellow
- Provvidenti, R. 1982. Sources of resistance or tolerance to viruses in
accessions of Cucurbita maxima. Cucurbit Genetics Coop. 5:46-47.
- Provvidenti, R., D. Gonsalves, and H. S. Humaydan. 1984. Occurrence of
zucchini yellow mosaic virus in cucurbits from Connecticut, New
York, Florida, and California Plant Disease
- Provvidenti, R., H. M. Munger, and A. O. Paulus. 1984. Epidemics of
zucchini yellow mosaic virus and other cucurbit viruses in Egypt in
the spring of 1983 Cucurbit Genetics Coop. 7:78-79.