Vat and Fn, Two Linked Genes in Muskmelon

admin

Cucurbit Genetics Cooperative Report 5:29-30 (article 15) 1982

M. Pitrat1, H. Lecoq2 and G. Risser1
I.N.R.A., B.P. 94, 84140 Montfavet-Avignon, France

Many viruses affecting melon are non-persistently aphid transmitted. Cucumber mosaic virus (CMV) is probably the most widespread, but Watermelon mosaic 1 and 2 (WMV-1 and WMV-2), and in France a third potyvirus tentatively named Muskmelon yellow stunt virus (MYSV) (3) may cause severe losses. This later virus seems to be very close to Zucchini yellow mosaic (ZYMV) recently described by Lisa, et at. (1981) in Italy.

A resistance to virus transmission by Aphis gossypii has been described as efficient against CMV transmission (1), and also against WMV-1, WMV-2 and MYSV transmission (2,7). Therefore, this resistance is not virus specific. Plants possessing this resistance may be infected by these viruses when inoculations are made mechanically, or using other aphid vectors such as Myzus persicae, A. fabae, or A. craccivora. The resistance is specific to the melon aphid A. gossypii.

Muskmelon lines from India (PI 164320, PI 414723) and from Far East (PI 161375, PI 255478, Ginsen makuwa, Kanro makuwa, Shiroubi okayama) possesses this form of resistance which has been shown to be governed by a single dominant gene (5). We propose for it the symbol Vat and the name Virus aphid transmission resistance.

MYSV induces various symptoms in muskmelon and two pathotypes have been described (3). F pathotype provokes a wilting and necrotic reaction on some cultivars (e.g. Doublon). This reaction is controlled by a semi-dominant gene which has been called Flaccida necrosis (Symbol Fn).

Vat segregates independently from Fom-1, Fom-2, ms-1, Wmv-1 and a but is linked with Fn (11.6+ 1.9 units).

Literature Cited

  1. Lecoq, H.S., Cohen, M. Pitrat, G. Labonne. 1979. Resistance to Cucumber mosaic virus transmission by aphids in Cucumis melo. Phytopathology 69:1223-1225.
  2. Lecoq, H., G. Labonne, M. Pitrat. 1980. Specificity of resistance to virus transmission by aphids in Cucumis melo. Ann. Phytopathol. 12:139-144.
  3. Lecoq, H. M. Pitrat, M. Clement. 1981. Identification et characterization d’un potyvirus provoquant la maladie du Rabougrissement Jaune du Melon. Agronomie 1:827-834.
  4. Lisa, V., G. Boccardo, G. d’Agostino, G. Dellavale and M. D’Aquiilio. 1981. Characterization of potyvirus that causes zucchini yellow mosaic. Phytopathology 71:667-672.
  5. Pitrat, M. H. Lecoq. 1980. Inheritance of resistance to Cucumber mosaic virus transmission by Aphis gossypii in Cucumis melo. Phytopathology 70:958-961.

1Station de.Amelioration des Plantes Maraicheres.
2Station de Pathologie Vegetale.