Pharmacology and Ethnopharmacology

Biography

Biography: Hoa Tran

Abstract

Xerospermum noronhianum (Blume) Blume, locally known as ké (leech’s longan) is a multipurpose fruit tree species of high economic importance, native to the limestone forests of Vietnam. This species along with lychee (Litchi chinensis Sonn) belong to the Sapindaceae family. The fruits of X. noronhianum are edible, with a sweet and pleasant taste, resembling those of Nephellium lappaceum, another Sapindaceae species that yields the commercially important Rambutan tropical fruit. The fruit of X. noronhianum is too small to be of any commercial value, but the species is a source of medicines against diarrhea, stomach pains and Alzheimer disease. Recently, ké has emerged as a high-priority species for domestication in Vietnam after a national survey and ranking of non-timber forest products. Information on the level of genetic variation and the extent of genetic diversity within and between natural and managed populations is needed to develop strategies for domestication and to define units of in situ conservation as natural gene pools or forest gene banks for this species. Microsatellites (SSRs) provide an ideal tool to investigate genetic variation pattern. However, given the time-consuming and expensive process of isolating SSRs, it is advantageous to utilize primer sequences already identified in other closely related species. We investigated the transferability of 14 lychee (L. chinensis) Simple Sequence Repeat (SSR) loci to ké (X. noronhianum).Ten primer pairs were found to be transferable (71.4%), whereas seven revealed polymorphisms (70%). The average number of alleles per locus has dropped from 6.1 for lychee to 4.7 for ké. The loci were polymorphic in 110 individuals from 5 populations in Vietnam, with 2 to 10 alleles per locus and observed heterozygosity ranging from 0.14 to 0.76. The relatively high frequency of cross-transferability observed in this study is rather unexpected as ké belongs to the Sapindoideae subfamily, while lychee, pulasan, and longan belong to subfamily Nepheleae and are, therefore, more closely related. However, this study showed that the SSR markers developed in lychee are a good source of molecular markers for X. noronhianum.