Cucurbit Genetics Cooperative Report 3:30 (article 16) 1980
H. Lecoq and M. Pitrat
Station de Pathologie Vegetale, INRA, Domaine Saint Maurice, 84140 Montfavet, France (first author); Station d’Amelioration des Plantes Maraicheres, INRA, Domaine Saint Maurice, 84140 Montfavet, France (second author)
Aphid borne cucumber mosaic virus (CMV) causes one of the major disease affecting muskmelon crops in southeastern France. Risser et al. (1) have started a breeding program to introduce an oligogenic recessive resistance to CMV “common” strains found in Cucumis melo line PI 161375 (‘Songwhan Charmi’ = SC) into Charentais type muskmelon. However, this resistance does not prevent some CMV isolates (grouped in the “Song” pathotype) to infect SC after mechanical inoculation. “Song” pathotype represents 35% of over 1000 CMV isolates collected in naturally infected weeds and vegetables (3). It was important to look for any other form of resistance to CMV in C. melo. We report here the discovery, also in SC, of a resistance to CMV “Song” strains transmission by Aphis gossypii,one of the major vectors of this virus in our field conditions. The melon aphid, although transmitting very efficiently CMV “Song” strains to a susceptible muskmelon cultivar was found to be unable to transmit this virus to SC, even in conditions where 100% of the susceptible plants are infected (2).
This resistance is governed by a single dominant gene independent of the oligogenic recessive resistance to CMV “common” strains and this gene control a form of resistance of melon to A. gossypii by non-preference. This resistance was also found in five other melon lines: three from Japan (‘Ginsen Makuwa’, ‘Kanro Makuwa’ and ‘Shiroubi Okayama’) and two from India (PI 164320 and PI 414723).
Resistance to CMV transmission is specific to A. gossypii; indeed, Myzus persicae, another efficient CMV vector in our field conditions, is able to transmit CMV “Song” strains to SC, although it is with a lower efficiency than to a susceptible variety.
Literature Cited
- Risser, G., M. Pitrat, J. C. Rode. 1977. Ann. Amelior. Plantes 27:509-522.
- Lecoq, H., S. Cohen, M. Pitrat, G. Labonne. 1979. Phytopathol. 69:1223-1225.
- Leroux, J. P., J. B. Quiot, H. Lecoq, M. Pitrat. 1979. Ann. Phytopathol. 11:(in press).