Ken Takahata, Ken
Faculty of Agriculture, Tokyo University of Agriculture, Funako, Atsugi, Kanagawa 243-0034, Japan

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INVASIVE WEEDS IN BOGOR BOTANIC GARDENS, INDONESIA AND ITS IMPLICATION ON SURROUNDING LANDSCAPES Santosa, Edi; Widiyanto, Gunar; Lontoh, Adolf Pieter; Agustin, Elly Kristiati; Takahata, Ken; Mine, Yoko; Sugiyama, Nobuo
Buletin Kebun Raya Vol 17, No 2 (2014): Buletin Kebun Raya Vol. 17 (2) July 2014
Publisher : Center for Plant Conservation Bogor Botanic Garden, Indonesian Institute of Sciences

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Abstract

Conservation areas with the objective for collection and exchange plant materials have been speculated as weed bank for surrounding areas. Objective of this study was to identify and characterize ruderal invasive weeds in the Bogor Botanic Gardens (BBG). Observations were conducted in all vak (collection blocks) in the BBG in order to identify the weeds species, determine their invasiveness, dominance and distribution. Weeds associations with host plants were observed. Current weed control program and data of dead trees collection were analyzed in relevant to weed. Distribution of weeds outside BBG was observed by transects method following river and road directions. Results showed that there were seven invasive weeds, i.e., Cecropia adenopus (Cecropiaceae), Cissus nodosa Blume (Vitaceae), Cissus sicyoides Blume (Vitaceae), Dioscorea bulbifera L. (Dioscoreaceae), Ficus elastica Roxb. (Moraceae), Mikania micrantha H.B.K. (Asteraceae) and Paraserianthes falcataria (L.) Nielsen (Fabaceae). These seven weeds species invaded 41 out of 215 plant families in BBG. Six species of weeds, i.e., C. adenopus, C. nodosa Blume., C. sicyoides Blume., D. bulbifera L., M. micrantha H.B.K. and P. falcataria (L.) Nielsen, were introduced as BBG collections for the first time while the F. elastica Roxb was considered as native. It is most likely that the weeds dispersal agents are the wind, birds, bats, visitors, and waters. All of these weeds existed in surrounding areas outside BBG. Given the detrimental impact of invasive weeds on the plant collection in BBG, it is necessary to develop long–term comprehensive control measures both inside and neighboring areas by involving other government authorities beyond BBG.
NPK Fertilizers for Elephant Foot Yam (Amorphophallus paeoniifolius (Dennst.) Nicolson) Intercropped with Coffee Trees Santosa, Edi; Susila, Anas Dinurrohman; Lontoh, Adolf Pieter; Noguchi, Arisa; Takahata, Ken; Sugiyama, Nobuo
Jurnal Agronomi Indonesia (Indonesian Journal of Agronomy) Vol. 43 No. 3 (2015): Jurnal Agronomi Indonesia
Publisher : Indonesia Society of Agronomy (PERAGI) and Department of Agronomy and Horticulture, Faculty of Agriculture, IPB University, Bogor, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (724.124 KB) | DOI: 10.24831/jai.v43i3.11253

Abstract

ABSTRACTFertilizer application in elephant foot yams (Amorphophallus paeoniifolius (Dennst.) Nicolson) intercropping system is rare in Indonesia, therefore, NPK fertilizers experiment was conducted under the shade of 10-year-old coffee plantation at Leuwikopo Experimental Farm, Bogor, Indonesia, in order to increase the productivity of elephant foot yam intercropped with coffee trees. Prior to planting, 20 ton ha-1 of goat manure was applied. Four NPK combinations, i.e., N, P2O5, K2O at the rate of 0, 0 and 0; 100, 60 and 80; 125, 60 and 100; and 150, 60 and 120 kg ha-1, were applied. Results showed that there were no significant differences in leaf number per plant, petiole size and rachis length among treatments. Application of NPK decreased photosynthetic rates, while increasing rate of N and K2O had no effect on photosynthetic rates. NPK application at the 100 N, 60 P2O5 and 80 K2O kg ha-1 (N100P60K80 treatment) or larger prolonged growth duration regardless of NPK levels, and there was a close relationship between corm yield and growth duration. As a result, corm fresh mass was higher in the 100:60:80 kg ha-1 treatment than in control. In the N125P60K100 and N150P60K120 kg ha-1 treatments, leaves were damaged by heavy rains and winds, counteracting beneficial effect of NPK on growth duration and corm yield. These results suggested the importance of delay of entering dormancy for an increase in productivity of A. paeoniifolius.Keywords: NPK fertilizers, photosynthesis, productivity, prolong growth, tuber crop
Isolating Microsatellite From Amorphophallus variabilis and Its Application for Population Study in Dramaga Conservation Forest, Indonesia Santosa, Edi; Lian, Chun Lan; Mine, Yoko; Takahata, Ken; Sugiyama, Nobuo
BIOTROPIA Vol. 25 No. 1 (2018): BIOTROPIA Vol. 25 No. 1 April 2018
Publisher : SEAMEO BIOTROP

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (195.087 KB) | DOI: 10.11598/btb.2018.25.1.652

Abstract

Amorphophallus variabilis Blume, a member of Araceae, is a fleshy perennial tuber crop endemic in Java Island, Indonesia. The plant produces white edible corm; and it was used as food during famine time before 1960s. Rapid ecological changes and land fragmentations in Java in recent times threaten populations of A. variabilis. Here, compound microsatellite markers were developed in order to develop conservation strategies in the populations. Twelve primers pairs produced high polymorphism ranging from 5 to 22 alleles per locus. The observed and expected heterozygosities ranged from 0.191 to 0.851 and 0.380 to 0.943, respectively. This high allelic diversity indicates that these markers are suitable for the study on population genetic structure. Cross-amplification on related and non-related species was performed. Application of the markers on populations from Dramaga Conservation Forest revealed high allelic richness, high diversity within and among populations. Genetic distance among populations increased with an increase of geographic distance. Present study suggested that, it is important to study population of A. variabilis in Java in order to understand the population genetic structure and develop effective in situ conservation programs.