EFFECT OF GENOTYPE ON SOMATIC EMBRYOGENESIS IN PISTACHIO (PISTACIA VERA L.)

Genotypes representing eight botanical cultivars of pistachio (Pistacia vera L.) were assessed for somaticembryogenesis and subsequent plant conversion from immature kernels. Embryogenic masses (EMSs) wereproduced from kernels of immature fruit of pistachio cultured in liquid MS medium with Gamborg vitamins,supplemented with 100 mgl1 casein hydrolysate, 100 mg l-1 L-Ascorbic acid, 3% sucrose, and BAP. EMSdif-ferentiated directly from the kernels after culture for 2 weeks in liquid medium with 0.5 mg l-1 BAP.Genotype x collection date had large effects on initiation of somatic embryogenesis. Embryogenic tissuescontaining em-bryoid or individual somatic embryos were isolated from the original tissue and used to initiaterepetitive liquid or agarified cultures. To determine the effects of genotypes during maturation on thesubsequent germination and plantlet generation, clusters of EMSs from the different genotypes weretransferred from liquid medium onto the surface of 5.7% ağar solidified MS medium with Gamborg vitamins,containing 4% sucrose, 1.0 mg l1 BAP and 0.5 mg l-1 IBA. After 4 weeks, individual or clusters of maturesomatic embryos were transferred from maturation medium onto the germination medium (GM). The numberof matured and germinated somatic embryos was influenced by the genotype in the maturation medium.Acclimatized plantlets resumed growth after transfer to a soil and peat mixture, and many developed tomaturity.