Teak (Tectona grandis L.f.) is considered to be an extraordinarily durable building timber with a worldwide reputation. Its widespread use has entailed the overexploitation of natural forests and a large reduction in natural diversity. Fifteen microsatellite markers were used to study the genetic variability and structure of 166 teak trees distributed over the whole natural area of teak. Analysis showed that in the teak natural area there were four main centers of genetic variability. Two clusters were in India and could be considered as main centers of genetic diversity in teak. The third cluster mainly consisting of populations in Thailand and Laos was genetically very distinct from the Indian populations but presented only half as much allelic variability. A fourth cluster from Central Laos showed even less genetic variability. The use of SSR markers for conservation of teak forest diversity is discussed.

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The first introduction of Tectona grandis in Indonesia took place between the fourteenth and sixteenth centuries and in Africa in the nineteenth century. A total of 1.1 and 0.3 million ha, respectively were planted in the two areas. The extension of teak plantations often started from these first introductions. Unfortunately, the documentation concerning dates, planting stocks and the sources of origin of the teak imported into the different countries was very inaccurate. In this study, the use of 15 microsatellite molecular markers enabled us to compare 22 exotic teak provenances with 17 provenances of the natural range. Results of the analysis showed that the provenances from South India were not related to the provenances that were first introduced in either Africa or Indonesia. Nearly 95% of teak landraces in Benin, Cameroon, Côte d'Ivoire, Tanzania, Togo and Senegal came from North India, and 96% of Indonesian and Ghanaian teak appeared to be very closely linked to Central Laos. The genetic origin of introduced teak was confirmed by the main traits of interest of provenances observed in international trials. Thus, trees from North India had very bad stem forms compared to Laotian and Thai provenances, which generally had good stem forms but low vigour. This genetic knowledge is essential for programmes to develop varieties and to improve the quality of plantations, particularly in Africa.

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Bamboo and rattan are widely grown for manufacturing, horticulture, and agroforestry. Bamboo and rattan production might help reduce poverty, boost economic growth, mitigate climate change, and protect the natural environment. Despite progress in research, sufficient molecular and genomic resources to study these species are lacking. We launched the Genome Atlas of Bamboo and Rattan (GABR) project, a comprehensive, coordinated international effort to accelerate understanding of bamboo and rattan genetics through genome analysis. GABR includes 2 core subprojects: Bamboo-T1K (Transcriptomes of 1000 Bamboos) and Rattan-G5 (Genomes of 5 Rattans), and several other subprojects. Here we describe the organization, directions, and status of GABR.

Allanblackia parviflora A. Chev. (Clusiaceae Lindley) is an indigenous tree species which is found in the rain forest regions of Ghana. It is a potential candidate fruit tree species being introduced in agroforestry systems. Information on genetic diversity, reproductive biology and fruit yield are not known. Field expeditions to seven populations of Allanblackia parviflora in Ghana were undertaken in 2003-2006 during which fruits were collected from 109 trees for characterization. The species was found to be dioecious. The colour of flowers varied from whitish to reddish. No ecological differences in number of fruits per tree, fruit shape and seed health were observed. However, large variations in fruit size and shape were observed among individual trees sampled. A high heritability (h 2 = 0.822) in fruit size and genetic gain (G = 20.1%) in fruit size for selection of trees with above average fruit size were observed. A positive significant correlation was observed between fruit size and seed weight (R = 0.54, P \ 0.05; Fig. 6). The results suggest that selection and cloning of trees with large fruits could lead to higher yield of seeds for oil production.

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Teak (Tectona grandis Linn. f) is a hardwood species of worldwide reputation. It occurs naturally in India, Thailand, Myanmar and Laos. Fifteen highly polymorphic microsatellite loci were developed from a genomic library enriched for AG/TC repeats. Primers to amplify these loci were tested on 265 individual trees from different teak populations. An average of 14.7 alleles per locus were detected and expected heterozygosity ranged from 0.223 to 0.879. These loci constitute a powerful tool in investigating the mating system, gene flow, parentage analysis and population dynamics for use in sustainable management of teak forests and for in situ conservation purposes.