BIODIVERSITAS ISSN: 1412-033X Volume 20, Number 4, April 2019 E-ISSN: 2085-4722 Pages: 1180-1191 DOI: 10.13057/biodiv/d200434 Population and ecological study of agarwood producing tree (Gyrinops versteegii) in Manggarai District, Flores Island, Indonesia RIDESTI RINDYASTUTI ♥ , TITUT YULISTYARINI, AGUNG SRI DARMAYANTI Purwodadi Botanic Gardens, Research Centre for Plant Conservation and Botanic Garden, Indonesian Institute of Sciences. Jl. Raya Surabaya-Malang, Km. 65, Purwodadi, Pasuruan 67163, East Java, Indonesia. Tel.: +62-343-615033,  email: ride17@gmail.com Manuscript received: 26 February 2019. Revision accepted: 28 March 2019. Abstract. Rindyastuti R, Yulistyarini T, Darmayanti AS. 2019. Population and ecological study of agarwood producing tree (Gyrinops versteegii) in Manggarai District, Flores Island, Indonesia. Biodiversitas 20: 1180-1191. Gyrinops versteegii (Gilg) Domke is one of very important tree species listed in Appendix II CITES because of its economical value as a source of agarwood. Since this commodity has been harvested in a significant volume, the natural population of G. versteegii is continuously decreasing in size. A remnant forest of Pongkor is one of fragmented habitat of G. versteegii in the rest of other land use for rice farming in Flores Island. The purpose of this study were to investigate the population structure and importance value rank of G. versteegii among plant species in Pongkor Community Forest. A semi-purposive random sampling were used in this study to investigate the population of G. versteegii in Pongkor, Manggarai District. The result showed that G. versteegii in Pongkor Community Forest was abundant, especially in seedlings stage. G. versteegii were found in four stratas i.e., trees, poles, saplings and seedlings with densities of 6, 4, 15 and 23 plants ha -1 , respectively. Seedlings of G. versteegii were abundant while larger plants were rare. Moreover, G. versteegii has scattered distribution and the highest important values (IVI) for trees, poles and saplings stratas, with IVI of 17.42, 25.75 and 44.42, respectively, while among the ground covers, G. versteegii ranked 22 nd with an important value of 2.32. The abundant seedlings and the availability of adult trees as reproductive stages in the population of G. versteegii designated that population of G. versteegii in Pongkor could serve as a potential source of seed and young trees for plant enrichments in natural habitats and sustainable plantation in Manggarai District, Flores Island. Keywords: Agarwood, CITES, Gyrinops versteegii, population structure INTRODUCTION Agarwood is one of the highest economic non-timber commodities in the world yielding aromatic resin that is produced under fungal infection (FAO 2002; Zich and Compton 2001). Agarwood is widely used for various purposes, therefore, it has been harvested in a significant volume. In infected form, agarwood were used as perfume and incense. The products of agarwood are generally exported in the form of chunks of wood, debris, powder or aloes oil to Arabian countries, Singapore and China (Zich and Compton 2001; Turjaman and Hidayat 2017; Mohamed 2016). As traditional medicine, agarwoods were investigated farmacologically and were found as a central nerve deppresant (Okugawa et al. 1993), anticancer (Hashim et al. 2014; Dahham et al. 2016), digestive medicine (Kakino et al. 2010), and antioxidant (Huda et al. 2009). The most well-known plant groups which produce agarwood were the genera of Aquilaria and Gyrinops belonging to the family of Thymelaeaceae, subfamily of Aquilarioideae for their high quality resin production. There are eleven species of genera Aquilaria and seven species of genera Gyrinops which produce agarwood. Five of these species are Gyrinops versteegii, G. ledermannii G. decipiens, G. podocarpus, G. caudate, and G. salicifolia (natural habitat in Indonesia and Papua New Guinea) and G. walla (natural habitat in Sri Lanka) (Hou 1960; Schun and Cordell 1985). One of agarwood producing species which has been harvested hardly from its habitats is Gyrinops versteegii (Gilg) Domke (Zich and Compton 2001). G. versteegii is a tree that can reach a height of up to 10 m, 25-30 cm in diameter and has various leaf morphology (Siburian 2009; Surata and Soenarno 2011; Hou 1960). G. versteegii is divided into many various groups and varieties, however, it was still taxonomically intricated (Mulyaningsih et al. 2017; Mulyaningsih et al. 2017; Roemantyo and Partomihardjo 2010). G. versteegii is distributed from Lesser Sunda Island, especially Western Sumba, Alor Island, Lombok Island, Flores Island, to Sulawesi, Mollucas and Papua (Hou 1960). The population of G. versteegii in its distribution area was reported to decline continously because of hard harvesting of mature plants especially in Nusa Tenggara Barat and Nusa Tenggara Timur Provinces. Because of its high demand, the harvesting of agarwood producing trees is oftenly carried out without distinguishing the producing and non-producing trees (Zich and Compton 2001; Barden et al. 2000). This harvesting model significantly threaten the natural population of the species by decreasing its population size. This major threat to the population of agarwood producing trees results in the issue of a trade rules of export under the CITES (Convention on International Trade in Endangered Species) regulation. In Indonesia, the export of G. versteegii in the form of chips is in a low quota, however, the export has increased from 1000 kg in 2014 to 4000 kg in 2015 (CITES Trade