The research trial was carried out at University of California, Davis, Agriculture and Natural Resources, Cooperative Extension–Kearney Agricultural Center (KAC). Part of the scientific work in the laboratory started from November 1, 2001 throughout the end of February 2002. This trial was conducted using Pistacia vera; the female variety ‘Kerman’ and its pollinator, variety ‘Peters’;… both are grafted on the rootstock UCB1.