Thesis (BS Biology) -- University of the Philippines Mindanao, 2005

Fourteen durian cultivars from Alcon Farm in Davao City were analyzed using RAPD technique to determine their molecular characteristics and relationships. The five-arbitrary sequenced decamer primers generated a total of 30 distinct RAPD markers, ranging from 4 to 7 per primer. The sizes of the amplified products ranged from 51 to 2,572bp, both extremes recorded in Primer 2. The over-all extent of polymorphism was very high and the RAPD data were useful in detecting diversity among the 14 cultivars. There were however, cultivars like D-101, Chanee, Duyaya and Kob, which did not yield products in Primers 2,4,6 and 17 even after many attempts to amplify them. The five primers produced profiles that can collectively characterize all the 14 cultivars in terms of unique bands. The clustering analyses using different methods of dendogram construction (OARS and Fitch) had generated two identical topologies. Two lineages were identified among durian cultivars with a banana cultivar (Talip) used as outgroup. First the Seri Kembangan lineage and second the lineage of Umali, Lacson 2, Alcon Fancy, Arancillo, Oboza, Indonesian Native, Monthong Thailand, Monthong Sanchez and Puyat. This relationship was clearly supported by the bootstrap values in PARS (65%) and Fitch (66%). However, within the second lineage, diversity of these cultivars was detected though the bootstrap support in less than 50%. Probably the low bootstrap values on the node of the second lineage can be resolved if more RAPD primers were included in the analysis. The phylogenetic clustering of Monthong Sanchez and Monthong Thailand having strong bootstrap values (78%), Fitch (83%) and UPGMA (99%) was confirmed in these analyses. There is a high degree of genetic similarity at greater than 50% among cultivarsAlcon Fancy, Arancillo, Lacson 2, Monthong Sanchez, Monthong Thailand and Umali as validated in their PARS and Fitch clustering analyses