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Dive into the research topics where Ulfah J. Siregar is active.

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Featured researches published by Ulfah J. Siregar.


Tree Genetics & Genomes | 2006

Genetic diversity within and among populations of Shorea leprosula Miq. and Shorea parvifolia Dyer (Dipterocarpaceae) in Indonesia detected by AFLPs

Cui-Ping Cao; Reiner Finkeldey; Iskandar Z. Siregar; Ulfah J. Siregar; Oliver Gailing

The genetic diversity within and among populations of Shorea leprosula and Shorea parvifolia from Indonesia was investigated using amplified fragment length polymorphisms (AFLPs). The results indicated that S. leprosula is genetically more variable than S. parvifolia. At the population level, a higher level of genetic diversity was revealed for S. leprosula with a percentage of polymorphic loci (PPLp) of 53.32% and an expected heterozygosity (Hep) of 0.16 in comparison with S. parvifolia showing PPLp of 51.79% and Hep of 0.14. At the species level, S. leprosula showed PPLs of 92.86% and Hes of 0.21, while S. parvifolia showed PPLs of 85.71% and Hes of 0.21. Genetic differentiation (Gst) indicated that 25 and 31% of total genetic diversity in S. leprosula and S. parvifolia, respectively, were attributed to the differences among populations. An analysis of molecular variance (AMOVA) at two hierarchical levels exhibited that most genetic variation resided within populations with proportion of 70.2% for S. leprosula and 66.2% for S. parvifolia. The AMOVA at three hierarchical levels performed for S. leprosula and S. parvifolia together revealed that the genetic difference between the two species was remarkably higher with a proportion of 44.1% than the differences within and among populations (38.1 and 17.8%, respectively). The genetic differentiation between islands was significant for S. leprosula but not for S. parvifolia. The observed genetic diversity agreed with the life history traits of Shorea species. Highly differentiating individual AFLP markers were found for each species, which will serve as diagnostic markers for the identification of wood of different species, from different islands and regions.


Ecology and Evolution | 2012

Population structure and demographic history of a tropical lowland rainforest tree species Shorea parvifolia (Dipterocarpaceae) from Southeastern Asia

Hiroko Iwanaga; Kosuke M. Teshima; Ismael A. Khatab; Nobuyuki Inomata; Reiner Finkeldey; Iskandar Z. Siregar; Ulfah J. Siregar; Alfred E. Szmidt

Distribution of tropical rainforests in Southeastern Asia has changed over geo-logical time scale, due to movement of tectonic plates and/or global climatic changes. Shorea parvifolia is one of the most common tropical lowland rainforest tree species in Southeastern Asia. To infer population structure and demographic history of S. parvifolia, as indicators of temporal changes in the distribution and extent of tropical rainforest in this region, we studied levels and patterns of nucleotide polymorphism in the following five nuclear gene regions: GapC, GBSSI, PgiC, SBE2, and SODH. Seven populations from peninsular Malaysia, Sumatra, and eastern Borneo were included in the analyses. STRUCTURE analysis revealed that the investigated populations are divided into two groups: Sumatra-Malay and Borneo. Furthermore, each group contained one admixed population. Under isolation with migration model, divergence of the two groups was estimated to occur between late Pliocene (2.6 MYA) and middle Pleistocene (0.7 MYA). The log-likelihood ratio tests of several demographic models strongly supported model with population expansion and low level of migration after divergence of the Sumatra-Malay and Borneo groups. The inferred demographic history of S. parvifolia suggested the presence of a scarcely forested land bridge on the Sunda Shelf during glacial periods in the Pleistocene and predominance of tropical lowland rainforest at least in Sumatra and eastern Borneo.


Tree Genetics & Genomes | 2009

Genetic variation in nine Shorea species (Dipterocarpaceae) in Indonesia revealed by AFLPs

Cui-Ping Cao; Oliver Gailing; Iskandar Z. Siregar; Ulfah J. Siregar; Reiner Finkeldey

Shorea is the largest and most important genus of the Dipterocarpaceae. The genetic diversity and structure of nine Shorea species from two different locations, namely Nanjak Makmur in Sumatra and Sumalindo in Borneo, were evaluated using amplified fragment length polymorphism (AFLP) markers. A total of 274 trees were investigated at 85 polymorphic AFLP loci. Levels of genetic diversity of these species ranged from


Genes & Genetic Systems | 2017

Geographical variation in soil bacterial community structure in tropical forests in Southeast Asia and temperate forests in Japan based on pyrosequencing analysis of 16S rRNA

Natsumi Ito; Hiroko Iwanaga; Suliana Charles; Bibian Diway; John Sabang; Lucy Chong; Satoshi Nanami; Koichi Kamiya; Shawn Lum; Ulfah J. Siregar; Ko Harada; Naohiko T. Miyashita


Archive | 2012

Incorporating Social and Natural Science in the Restoration of an Indonesian Conservation Forest: A Case Study from Jambi

Ulfah J. Siregar; Iskandar Z. Siregar; S. Wilarso Budi; Yulius Hero; Didik Suharjito; Hardjanto

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Biotropia: The Southeast Asian Journal of Tropical Biology | 2014

Anatomical Characters of Aquilaria microcarpa Interacting with Fusarium sp

Rima Hs Siburian; Ulfah J. Siregar; Iskandar Z. Siregar; Erdy Santoso; Imam Wahyudi


Forest Policy and Economics | 2007

Economic analysis of sengon (Paraserianthes falcataria) community forest plantation, a fast growing species in East Java, Indonesia

Ulfah J. Siregar; A. Rachmi; M.Y. Massijaya; N. Ishibashi; K. Ando

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Jurnal Penelitian Hutan dan Konservasi Alam | 2009

SISTEM PERKAWINAN BAKAU BANDUL (Rhizophora mucronata Lamk) BERDASARKAN ANALISIS ISOZIM

Hamzah Hamzah; Ulfah J. Siregar; Chairil Anwar Siregar


Annales Bogorienses | 1998

Development of RAPD protocol for Shorea laevis

Ulfah J. Siregar; Enny Sudarmonowati; N. Sri Hartati

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Biodiversitas | 2018

Variation in seed morpho-physiological and biochemical traits of Java olive populations originated from Java, Bali, Lombok, and Timor Islands, Indonesia

Dede J. Sudrajat; Ichsan Suwandhi; Iskandar Z. Siregar; Ulfah J. Siregar

Collaboration


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Iskandar Z. Siregar

Bogor Agricultural University

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Dede J. Sudrajat

Bogor Agricultural University

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Irdika Mansur

Bogor Agricultural University

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Noor Farikhah Haneda

Bogor Agricultural University

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Nurul Khumaida

Bogor Agricultural University

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R Sri Wilarso Budi

Bogor Agricultural University

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Tedi Yunanto

Bogor Agricultural University

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Andi Sukendro

Bogor Agricultural University

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Didik Suharjito

Bogor Agricultural University

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