2018 ASHS Annual Conference

Compared to many fruit and nut crops grown in California, pistachio (Pistacia vera L.) is relatively slow to provide an economic return to growers. Typically, the first harvest does not occur in the San Joaquin Valley of California until the trees are five or six years old. Precocity, the ability of a cultivar or variety to produce nuts in a reduced time interval after planting, is a desirable characteristic in that producers can begin recouping their initial investment earlier. However, many of the cultivars grown in California, have not been compared in replicated and randomized scientific trials with the objective of evaluating differences in precocity, bloom timing, and nut quality characteristics. The objective of this research was to address this deficiency by comparing cultivars that are currently grown or were grown in California and variety selections that appear to have commercial potential from the U.C. breeding program or from farmer collections. In this single trial, planted in 2010 on clonal rootstock and located within the pistachio growing area of the southern San Joaquin Valley, we compared the following cultivars: Golden Hills, Joley, Kalehghouchi, Kerman, Lost Hills, Pete 1, Red Aleppo, Ruehle, and Sirora; and the varieties KB25-78, KA22-80 and Velez. Differences were found in precocity, bloom timing, nut weight, shell splitting and other nut quality characteristics, which should be of interest to commercial pistachio producers, processors and breeders.