ABSTRACT: Samples of leaves, buds, fruits, and fruit clusters of pistachio (Pistacia vera) were collected during the middle crop seaason from different localities in the Central Valley, California. Washings of the plant samples were sprayed on acidified potato dextrose agar (APDA), and fungal isolates were made by transfering them to PDA plates. Twenty six genera, representing fifty six fungal species, including four ascomycetes, one basidiomycete, 48 mitosporic fungi, two zygomycetes, and one yeast, were recovered from both leaf and fruit cluster washings and surface sterilized tissues. Forty four fungi are recorded for the first time from pistachio in the world. A new species of Exserohilum, E. parlierensis sp. nov., is described and illustrated, and its affinity to closely related species in the same genus is discussed to show the distinguishing morphological features.

KEYWORDS: pistachio, Exserohilum parlierensis, new species

NOMENCLATURAL NOVELTIES:
Exserohilum parlierensis W.Q. Chen & Michailides, p. 153