discriminate analysis

Here and for the first time, this paper reports sex determination of cycad (Cycas revoluta Thunb.) befor maturity and cone formation. Sex determination in cycad is possible only after maturity and cone formation. At least, the 10 to 12 years in optimal conditions is needed for cycad to reach maturity. In this research, two-year old male and female off-shoots of cycad were separated from the adult male and female plants and were treated in natural conditions, uniformly. Morphological characteristics of male and female plants were visually compared. Anatomical features were studied on the sections prepared from primary leaf rachis, leaflet and root by light microscope. According to the Discriminate Analysis (DA) method, differences between morphological characteristics of male and female plants such as leaf rachis diameter, leaflets width, leaflets distance on the rachis, leaflets angle on the rachis, roots diameter and length, were significant. The arrangement of leaves in one third of middle part was bipinnate with opposite leaflets and bipinnate with alternate leaflets in male and female plants, respectively. New leaflet initiates to forms befor and after completely formation of previous leaflet in female and male plants, respectively. Anatomical studies showed that the difference between the lengths of lower stomata in male and female leaflets were significant. Type of stoma in cycad leaf is actinocytic.

Carpinus betulus is an important element in the Hyrcanian forests that extensively are distributed, therefore comprehensive studies on separation of phenotypes of the species is necessary. Most taxonomists approved the significance of the seed and bract traits in the taxonomy of the Carpinus so in this study these traits was utilized to identify different phenotypes of the C. betulus by 26 seed and bract characters. First multivariate analysis such as Cluster Analysis were used. Accuracy of the clustering was determined by Discriminate Analysis. Most important traits for groupings were surveyed by Wilks› Lambda values. The results showed the length of three lobes of bract had the most contribution in separation of the clusters. However some traits such as length, width and the ridge numbers o the seed are suitable in separation of the phenotypes. Also, examining the bract stomatal traits in different groups, showed this character-was efficient in identifying the different phenotypes. Additionally, we compared the results of this research with previously reportedvarieties of Carpinus betulus and we observed more variation than the prior studies. In fact this study showed extensive variability of Carpinus betulus especiallyin seed and bract characters, proving the taxonomy significance of these traits.