BIOTROPIA - The Southeast Asian Journal of Tropical Biology
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SYSTEM DYNAMICS MODELING OF LAND USE CHANGE IN WEST KALIMANTAN, INDONESIA
Get PDFThe main effects of human activities on the environment result in land use and land cover changes. Land overexploitation and development activities in West Kalimantan of Indonesia necessitated the focus of this research which aims to analyze and predict land use changes in West Kalimantan. The results of such a study assist researchers, planners, and policy makers to formulate suitable land use policies in the future in order to balance economic development and natural resource conservation. Moreover, it makes Indonesia shift from middle income to become a developed country in 2030. Methodology employs field observation, key informant interviews, focus group discussions, and system dynamics modeling. The field observation covered communities in several locations in the study site to identify patterns of land use. The system dynamics was applied to analyze the land use change system and estimate the extents of land cover change in the future. The study showed several outcomes: (i) The main leverage factors in the land use change system in West Kalimantan were the desire to reach the expected economic growth and the increased per capita consumption of edible oil globally; (ii) In the business-as-usual modeling, the increasing global demand for edible oil will lead to significant increment of oil palm plantation area, even the total area of plantation could be wider compared to that of the remaining forest area by 2030; (iii) Key interventions that need to be considered in the future is to conduct reforestation (with reforestation rate of at least 0.5% per year) and limited oil palm plantation development to a maximum of 50% of developed area
ASSESSMENT OF SEEDLING ABUNDANCE, SURVIVAL AND GROWTH OF TWO DIPTEROCARP SPECIES IN PEAT SWAMP FORESTS OF BRUNEI DARUSSALAM
Get PDFDryobalanops rappa Becc. and Shorea albida Sym. are Bornean endemics of high conservation value and increasingly threatened by anthropogenic disturbances. In-situ study of seedling abundance and growth performance of these Dipterocarp species was conducted in two selected peat swamp forests of Brunei Darussalam, following a mast fruiting event in March–May 2014. Within six 6 × 6 m plots at each forest site, D. rappa seedlings at the Anduki peat swamp forest and S. albida seedlings at the Badas peat swamp forest were measured for abundance at the initial census in September 2014, as well as survival and relative growth rates (RGR) after a period of 5 months, with the final census in February 2015. We found significantly higher seedling abundance for D. rappa (1885 ± 208) than S. albida (160 ± 71). Significantly higher percentage survival was recorded for D. rappa seedlings (90.8 ± 2.2%) in comparison to S. albida seedlings (81.7 ± 2.2%). S. albida seedlings (0.24 ± 0.02 mm mm⁻¹ month⁻¹) showed significantly greater RGR in stem diameter than D. rappa seedlings (0.18 ± 0.02 mm mm⁻¹ month⁻¹), however, there were no significant differences in the RGRs based on seedling height, leaf number and biomass between D. rappa and S. albida seedlings. In terms of seedling abundance and percentage survival, D. rappa seedlings appeared to be more successful in regeneration and may potentially be used for rehabilitation of degraded tropical peat swamps and other forest types. Our results suggested that greater conservation efforts of peat swamps must be made to protect the Bornean endemic plant species, in particular S. albida
AGROBACTERIUM-MEDIATED GENETIC TRANSFORMATION OF SEAWEED Kappaphycus alvarezii USING Gα GENE AND CALLUS CULTURES
No full textCottonii seaweed (Kappaphycus alvarezii Doty) is one of the most important commercial sources of carrageenan, which is widely used in the pharmaceutical and food industries. A major problem in the cultivation of this seaweed is ice-ice disease, which is caused by extreme changes in environmental conditions such as temperature and seawater salinity. Gene transformation to produce transgenic Kappaphycus lines that are tolerant to environmental stress is a potential solution to this problem. The Gα gene, which encodes the heterotrimeric G-protein alpha subunit, plays an important role in tolerance to biotic and abiotic environmental stress. This study aimed to: (a) introduce the Gα gene into the callus cells of K. alvarezii and regenerate transformed callus cells into transgenic plantlets; and (b) determine the appropriate concentration of acetosyringone and Agrobacterium tumefaciens strain for successful gene transfer into the callus of K. alvarezii. The callus cells of K. alvarezii were transformed using Agrobacterium tumefaciens strains LBA4404 and EHA105 carrying the expression vector pGWB502-Gα under the control of the CaMV-35S promoter. The calli and A. tumefaciens were co-cultivated in different concentrations of acetosyringone (20, 40, and 60 mg/L). The regeneration of transformed callus cells into transgenic plantlets was successfully achieved using the somatic embryogenesis technique. The results showed that the highest percentage of putative transgenic micropropagule formation occurred at acetosyringone concentrations of 20–40 mg/L. Polymerase chain reaction (PCR) analysis of twenty regenerated plantlets indicated that the Gα gene was successfully introduced into the genomic DNA of all samples. The highest transformation efficiency was obtained from the 20–40 mg/L acetosyringone co-cultivation treatment (22–28%). The transformation efficiency produced by Agrobacterium tumefaciens EHA105 (23%) was not significantly different from that produced using strain LBA4404 (15%)
ISOLATING MICROSATELLITE FROM Amorphophallus variabilis AND ITS APPLICATION FOR POPULATION STUDY IN DRAMAGA CONSERVATION FOREST, INDONESIA
Get PDFAmorphophallus 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
REVIEW: SOLUTIONS FOR GRAND CHALLENGES IN GOAT AND SHEEP PRODUCTION INDUSTRY
No full textGoats and sheep are valuable as they are a source of meat, milk, fleece, and other products. These livestock are also important both for agriculture and biomedical research. However, the efficient, sustainable, and profitable production of these small ruminants faces major obstacles. Hence, this review analyzes these major challenges specifically, their negative impacts on the industry, and suggests some science-based solutions to overcome them. Those challenged areas are education and training, research, translational research/biotechnology, goat and sheep health, and maintenance of an economically sustainable agribusiness. The suggested solutions include the effective teaching of goat and sheep science to the next generation and public empowerment, support for innovative and translational research, disease prevention and treatment, support for technology transfer, and development of sound agribusiness practices. This review is helpful particularly for scientists, students, and the goat and sheep producers. In general, these information on the current state of goat and sheep agriculture will also help the public to better understand and appreciate the challenges met and opportunities provided in small ruminant production enterprises
WATER POLLUTION LEVELS IN THE SUWUNG ESTUARY, BALI, BASED ON BIOLOGICAL OXYGEN DEMAND
No full textBiological Oxygen Demand (BOD) is generally used for determining water pollution levels in bodies of water. An estuary is a semi-enclosed body of water that can be polluted via land areas or rivers. This study was conducted to determine the spatial distribution of water pollution levels in the Suwung Estuary in Bali based on BOD₅ analyses conducted in January and February 2016. Samples were taken at 20 points (19 points in the Suwung Estuary and 1 outside the Suwung Estuary as a control). BOD₅ samples were then analyzed in the laboratory. Our BOD₅ analyses used the amperometric method based on the National Field Manual for the Collection of Water-Quality Data, Chapter A7. BOD₅ samples were taken during all tidal cycles, from low to high tide and high to low tide. BOD₅ values ranged from 0.84 mg/L to 9.47 mg/L during low to high tide and from 0.96 mg/L to 8.75 mg/L during high to low tide. The BOD₅ concentration in the Suwung Estuary indicated slight contamination during both tidal conditions. The spatial distribution of BOD₅ concentration was higher around cage aquacultures, rivers, the Suwung Landfill, and near the Benoa Harbour
THE PECULIAR PETIOLE CALLUSES GROWTH OF Amorphophallus titanum (Becc.) Becc. ex Arcang AND ITS IMPLICATIONS FOR EX SITU CONSERVATION EFFORTS
No full textAmorphophallus titanum is a plant species endemic to Sumatera. Land degradation and illegal capture of hornbills (a distributor of A. titanum seeds) is leading to potential extinction of A. titanum in the wild. In order to conserve the species and save it from extinction, there is an urgent need to develop methods to propagate it both in situ and ex situ. The aim of this research was to discover environmental factors triggering callus growth from petiole cuttings of A. titanum in its natural habitat in Sumatera and to determine the viability of callus pieces as a propagation material. A completely randomized design with a single factor, i.e., callus size, was employed on five callus replicates. Each replicate consisted of four callus samples. The treatments consisted of three callus piece sizes, i.e., 0.5 × 0.5 cm, 1 × 1 cm, and 2 × 2 cm. For each replicate, the following parameters of growth were assessed: the time of appearance of shoots; the shoot height when the first leaf fully opened; the petiole diameter; the diameter of the leaf lamina; and the number of young shoots. The results of our field observations showed that environmental factors such as temperature, humidity, and soil influence the formation of the callus in the wild. The size of the callus affected the shoot and root growth. The best result was obtained from callus 2 cm², which produced 2–3 shoots with an average height of 18.8 cm at the time of first fully opened leaf. The collection of petiole calluses of A. titanum that formed in its natural habitat is recommended instead of carrying the tuber. This ex vitro callus can be used as propagation material and then planted in botanic gardens as one of ex situ conservation efforts
GROWTH AND MEAT QUALITY ENHANCEMENT OF STRIPED CATFISH (Pangasianodon hypophthalmus) USING RECOMBINANT GROWTH HORMONE
No full textThe application of fish recombinant growth hormone (rGH) has been known as one of the methods to improve the growth performance of cultured fishes, one of which is the striped catfish Pangasianodon hypophthalmus, a species that is becoming commercially attractive in Indonesia. Hence, this study was aimed to evaluate the effects of rGH supplementation in commercial diet on the growth, feed utilization and flesh quality in P. hypophthalmus grow out. The rGH was mixed with chicken egg yolk and sprayed on the commercial feeds with different protein levels (32, 28 and 23%). In the control, the feeds were also sprayed with chicken egg yolk but without rGH. Striped catfish with body weights of 110.66 ± 1.32 g ind-1 were fed on rGH-supplemented diets two times a week during the first and third months, and during the rest of the months they were fed on diet without rGH supplementation. The fishes were reared for 120 days in 18 hapa (2×1×1.5 m3) with initial density of 20 fishes per hapa. The result showed that the highest weight gain, specific growth rate (SGR), and lowest feed conversion ratio (FCR) were obtained by fishes fed on 32% protein content with rGH-supplemented diet. No significant difference was observed in the weight gain, SGR and FCR in rGH treated group with 28% protein content with rGH supplemented diet and non-rGH control group receiving 32% protein diet. Similar moisture content of meat, protein content of meat, belly fat and edible portion were observed in rGH-supplemented diet and their control. Except in the treatment 23% protein content rGH supplemented diet that has lower lipid content in fish body and meat. The highest SGR was obtained when the fishes were fed on the 32% protein feed combined with rGH. Enrichment with rGH depleted the fat content in the meat of fish fed on all levels of protein in which the lowest fat was found in the 23% protein feed
ISOLATION, CHARACTERIZATION AND MOLECULAR IDENTIFICATION OF MYXOBACTERIA FROM TWO OUTERMOST ISLANDS OF INDONESIA
Get PDFMyxobacteria are Gram negative bacteria commonly found in soil, tree bark, and decay wood. These bacteria have unique social behaviors by forming fruiting bodies, moving by gliding motility and preying on other microorganisms. The research was conducted to isolate, characterize, and identify indigenous myxobacteria from Sumba and Papua Islands of Indonesia as a preliminary step to utilize their potential in the pharmaceutical industry. Myxobacteria were isolated using filter paper and baiting with Escherichia coli to obtain cellulolytic and bacteriolytic myxobacteria, respectively. Characterization of myxobacteria was performed with Gram staining, observation on pigmentation, morphology of vegetative cells, fruiting bodies, and myxospores. Molecular identification was conducted based on 16S rRNA gene sequence analysis. A total of 10 myxobacterial strains were successfully isolated and purified. All isolates obtained were Gram negative, rod shaped with yellow or orange pigmentation. Fruiting bodies observed contained spherical myxospores. Molecular identification of these bacterial strains showed that they belong to myxobacteria from suborder Cystobacterineae, namely Myxococcus fulvus, Myxococcus stipitatus, and Melittangium lichenicola. To our knowledge, this is the first record of their occurrence in Indonesia
PLACEMENT OF Syzygium boerlagei (Merr.) Govaerts (MYRTACEAE) CONFIRMED WITH atpB–rbcL INTERGENIC SPACER
No full textA molecular analysis was conducted to determine whether Eugenia boerlagei Merr. (Myrtaceae) belongs to genus Eugenia or Syzygium based on sequences of cpDNA fragments namely atpB-rbcL intergenic spacer. The study used seven specimens of Syzygium sect. Jambosa, three of Syzygium sect. Syzygium, two of Eugenia s.s. and one of Eugenia boerlagei Merr. with Baeckea ovalifolia and B. tuberculata as the outgroup. The results show that Eugenia boerlagei is appropriately placed under the genus Syzygium