INBREEDING, COANCESTRY, AND FOUNDING CLONES OF ALMONDS OF CALIFORNIA,MEDITERRANEAN SHORES, AND RUSSIA

The mean inbreeding and coancestry coefficients were calculated for al mond, Prunus dulcis (Miller) D.A. Webb, cultivars from the United Stat es, France, Spain, Israel, and Russia. To improve cultivars to meet ma rket demand, the recurrent use of four selections as parents in U.S. b reeding programs has resulted in a mean inbreeding coefficient (F) of 0.022 in this collection. In France, a single cultivar, Ferralise, has an inbreeding value of F = 0.250, while cultivars of other almond-pro ducing countries are noninbred (F = 0). Due to the use of common paren ts, U.S., Russian, and Israeli cultivars share coancestry, while coanc estries also exist between French and Spanish almond germplasm. Cultiv ars of known parentage in the United States, Russia,Israel, France, an d Spain trace back, respectively, to nine, eight, three, four, and thr ee founding clones. Future almond-breeding programs may narrow the gen etic base and thereby limit genetic gain.