Karyotype analysis of microprogated mature male and female pistachio trees (Pistacia vera L.)

First, in this study methods are described for the microprogation of mature apical shoot tips of male and female Pistacia vera L. cv. Siirt, then only the root tips of male micropropagated shoots and in vitro germinated seeds were used for karyological studies and the karyotyping of male and female Pistacia vera L.Before the axenic cultures were initiated on a MS medium supplemented with 1.0 mgl?1 BA, the explants were disinfested in 15% NaOCl (40 min.). BA again at 1.0 mgl?1 as this gave the best results for shoot multiplication studies. It was determined that the optimum dipping concentration and time are: l grl?1 and 20 s. for rooting studies conducted by dipping the basal-cut-ends of in vitro micropropagated shoots into a dense IBA solution.Second, a successful karyotype analysis was developed for the whole root tips propagated in vitro. The conclusions obtained from the morphological analyses of the chromosome studies determined the chromosome complement as 2n = 30 with metacentric, submetacentric, subtelocentric and telocentric pairs. Neither polyploidy nor satellite were detected on any of these chromosome plaques.It was found that the biggest chromosome pairs on the complement have metacentric centromer, and these chromosome pairs were heteromorph in the male metaphase plaque; whereas they were homomorph in the female plaques. It was also determined that they are the sex chromosomes for Pistacia vera L. The karyotype formula for this can be stated as: K(2n:28+XX/Xy): 8sm+3m+2st+1t+XX/Xy. These results are then discussed for the sexual determination strategies of Pistacia vera L.