GENETIC VARIABILITY OF TEAK (Tectona grandis Linn. F.) BASED ON ISSR MOLECULAR MARKERS AND MORPHOLOGICAL CHARACTERIZATION

The aim of this work was to evaluate 50 genotypes of teak based on molecular markers ISSR. Among the genotypes studied, 12 were candidate trees, 36 were surrounding the candidates and 02 trees were considered superior based on the phenotype, according to the assessment of the producers. These genotypes were propagated through seminal via and are 10 to 12 years old in the field. For this study, young and expanded leaves of each genotype were collected in the field. Total DNA was extracted and the amplifications were made by PCR with 12 primers ISSR, previously selected. The samples were applied in agarose gel 1.5% and subjected to electrophoresis running. For visualization of the amplified products, the gel was stained with ethidium bromide and photodocumented in UV transilluminator. Data were analyzed using the program POPGENE 1.31 and diversity parameters were estimated. Dissimilarity analyzes were estimated by Jaccard Index and the dendrogram construction was made based on the UPGMA method. At the same time, the phenotypic analysis of morphological data regarding the candidate trees was conducted by multicategorical analysis. All analyzes were performed with the assistance of Genes Program. The 12 primers amplified 56 fragments. For polymorphic information content the indicators UBC 841, UBC 857 and UBC 807 provided higher values, 0.329, 0.327 and 0.303, respectively. The genetic diversity of the candidate trees (H = 0.1601 and I = 0.2301) was similar to the neighbors (H = 0.1507, I = 0.2178). The dendrogram generated by the UPGMA method formed 14 groups, while the grouping based on Tocher, 15 groups were formed. For the phenotypic analysis, the variable that most contributes to the diversity was the formation of catana. These results reflect that there is variability among the genotypes. It is possible to note, therefore, the need to expand the variability of the material, by introducing genotypes of different origins and genetically unrelated.