Phomopsis is a genus of ascomycete fungi in the family Diaporthaceae. It was previously in the Valsaceae family.

Species

680 records are listed by Species Fungorum; See List of Phomopsis species (for full list of species). Selected species list includes; Formerly placed here:

Dead-arm infection

One of the species of this genus, P. viticola, cause a grape disease called Phomopsis or dead-arm. Usually, infections begin during early growth stages in spring. This affects leaves, fruit, rachises, and shoots of a plant. This disease causes the formation of lesions on shoots, leaves, and rachises, but also can cause fruit rot. It causes significant economic damage to grape vines. Another Phomopsis species, P. juniperovora, infects junipers, and is a particularly important pest of seedlings and juvenile plants in the nursery industry.