Ana lysis of the Genetic D iversity of Sweet Tha i Tamr indIntroduced from Tha iland Ba sed on RAPD Markers

Random amp lified polymorphic DNA (RAPD) was emp loyed to study the genetic variation and genetic relationship of 10 sweet Thai tamarind ( Tam arindus ind ica) cultivars introduced from Thailand. The RAPD analysisshowed that 34 of 52 amp lified bands (65. 38% ) were polymorphic within the species, while the mean percentageof polymorphic bandswithin cultivarswas 25. 96%. The number of alleles Ao , effective number of alleles Ae , Nei’sgene diversity H, and Shannon’s information index I for the species were 1. 653 8, 1. 199 9, 0. 137 1 and 012279, respectively, and for the cultivarswere on average 1. 259 6, 1. 164 7, 0. 094 6 and 0. 140 3, respectively. Thelargest p roportion of the total RAPD diversitywas found within, rather than among the cultivars (GST = 0. 163). Thegenetic distance between cultivars ranged from 0. 013 1 to 0. 124 4, and on average was 0. 047. An analysis of 10cultivars using UPGMA showed that the introduced sweet Thai tamarind cultivars could be divided into three group sby 0. 02 genetic distance, the first group included Zichupoton,Buangka,Barchan, Shampoo and Ziton cultivar, thesecond group included Sritong, Srichompo, Prakaythong and Sritongbao cultivar, and the third group included onlyBargeton cultivar. The basic data were p rovided for further development and imp rovement of the cultivars in thisstudy.