PISTACHIO BREEDING AND GENETICS PROGRAM AT THE UNIVERSITY OF CALIFORNIA
An active program of pistachio breeding and genetic research is being conducted at the University of California, Davis. The cultivar development program was begun in 1989 with initial set of 1940 P.vera progeny from 78 crosses. In 1990, an additional 5470 seedlings were produced from 176 controlled crosses. These materials were planted out at 3 locations for evaluation. Each progeny family was divided into 6 groups, randomized and planted in 2 blocks per location. The locations selected for this research span the range of environments in which pistachio is likely to be commercially grown in California. Replication provides insurance against unexpected disasters such as localized soil pathogen problems. All seedlings were planted on their own roots, since trying to handle such a large number of unique genotypes in a nursery situation as well as the required grafting would have made the establishment of the program very expensive. During 1992 and 1993 about 2000 additional seedlings from interspecific crosses have been developed for use in rootstock and genetic studies. In addition to develpoment of materials for beeding and selection the program has also supported development of technologies for micropropagation of pistachio. This can now be done easily with immature P. vera, P. Integerrima, and some hybrid roodstocks. During 1992 and 1993 the phylogenetic relationships of 10 Pistacia species was studied using chloroplast DNA. Both RFLP and PCR approaches were used to reveal variation at the species level for classification. In addition to revising traditional claasifications for Pistacia species this study suggests that the genus have evolved very slowly. New counts of chromosome numbers for these species are being conducted with completed results expected by September. Preliminary results suggest that prior published results for several species are correct. The numerical series 24, 28 and 30 suggest an unusual evolutionary pathway for the genus.
Parfitt, D.E., Badenes, M.L., Ferguson, L., Maranto, J., Almehdi, A. and Guo Yang, L. (1995). PISTACHIO BREEDING AND GENETICS PROGRAM AT THE UNIVERSITY OF CALIFORNIA. Acta Hortic. 419, 279-280