In situ and Ex situ Conservation of Commercial Tropical Trees - ITTO

366Conclusions and RecommendationIsozyme, RAPD, and AFLP techniques were well suited for all species studied,which indicates that the techniques developed could be used, with or withoutslight modifications, for assessing genetic diversity in relation to conservationprograms for a broader range of tropical forest tree species. Genetic diversityof S. parvifolia, S. laevis, E. zwagerii and S. macropodum and linkagebetween certain phenotypic characters with genetic marker in P. falcatariacould be assessed using either isozyme, RAPD, or AFLP techniques. As anappropriate AFLP technique has been developed for two tree species,construction of a genetic map could be made, since the number of scorablebands was extremely high as compared to that obtained with isozyme andRAPD techniques. The superiority of this technique is beneficial for thedevelopment of commercial tropical forest tree breeding, as it will give strongfundamental information on important traits.Comparison between the three techniques - isozyme, RAPD, and AFLP- when used for analyzing one species led to the same conclusion for assessingthe impact of logging on genetic diversity. However, the grouping shown in thedendrogram was slightly different in that the genetic diversity values werereduced in the logged area compared with the un-logged area. For handlinglarge numbers of samples when time is limited, RAPD may be applied first forassessing genetic diversity as long as the procedure is established in one lab.But if the goal is to determine outcrossing rate or mating system in regard todeveloping a conservation strategy based on the status of inbreeding in a speciesor population, then isozyme markers would be the first choice.Isozyme techniques could be used to detect linkages between growthand quantitative characters of P. falcataria. The correlation was significant incertain loci and in certain subpopulations. Development of species shouldconsider not only performance during provenance trials but also during genetictests, as good growth correlates with certain isozyme patterns.Although the impact of logging on genetic diversity of S. parvifoliaand E. zwagerii in Central Kalimantan was not significantly different, appropriateconservation programs should be undertaken as it indicates that genetic diversitymay be reduced in the near future. Strengthening existing forest conservationreserves may be a first step to combating illegal logging in Indonesia. Strongerrecommendations could be proposed if there were further studies to obtainmore valid data. Future research must consider different logging andfragmentation histories, a broader range of environmental and physical conditions,and inclusion of more species.Fragmentation gave significantly different effects in terms of geneticdiversity of S. macropodum, but only between that grown in Pasir Mayang