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Resistance to aphids in melon was first identified in 1944. This resistance targets Aphis gossypii, a cosmopolitan species that is highly polyphagous. Resistance is observed in several melon accessions, and is controlled by a gene cluster. Since the description of the ‘aphid side’ of the pleiotropic Vat phenotype in the late 1960s, each decade has contributed to our knowledge and exploitation of this amazing gene. The ‘virus side’ of the pleiotropic phenotype was elucidated in the late 1970s, the first Vat cultivars were developed and deployed in the 1980s, with mapping in the 1990s. In the first decade of the 21st century, the Vat gene was assigned to the NBS-LRR R gene family, providing clues to its mode of action. We now have at least a partial understanding of this mode of action. During this period, a succession of new technologies such as electropenetrography provided insight into the pleiotropic phenotype of Vat melons. Our knowledge of the genetic diversity of A. gossypii has also been refined over time. This aphid species is composed of genetic clusters corresponding to different host races specializing on a particular plant family. The cucurbit host race contains lineages regularly observed on melon. The genetic diversity of the Cucurbit host race challenges Vat resistance in the field, but it also provides us with new opportunities to deepen our knowledge of the mechanisms underlying Vat resistance.

Frontiers in Plant Science, 7 (1420) DOI : 10.3389/fpls.2016.01420