BIOTROPIA - The Southeast Asian Journal of Tropical Biology
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BACTERIAL COMMUNITY SHIFTS OF A HIGH MOUNTAIN LAKE IN RESPONSE TO VARIABLE SIMULATED CONDITIONS: AVAILABILITY OF NUTRIENTS, LIGHT AND OXYGEN
Get PDFWe studied bacterial population composition shifts by exposing natural water samples to variable simulated environmental conditions. The samples were taken from Lake Jori XIII (2640 m a.s.l), an oligo-to mesotrophic cold freshwater lake, located in the eastern Swiss Alps. The Jori lakes are characterized as remote, unpolluted high mountain lakes with a long period of ice cover and typically low nutrient concentrations. Culture independent techniques (PCR-based analyses) were used for detection and molecular characterization of a large number of bacteria most of which are still uncultivable. Bacterial community shifts over three ecological conditions (nutrients, light and oxygen availability) were detected by using Temporal Temperature gradient Gel Electrophoresis (TTGE) of a PCR-amplified part of the 16S rRNA gene. The bacterial populations responded differently to the variable conditions, as revealed by TTGE pattern shifts during the experiment. Key words: Temporal Temperature gradient Gel Electrophoresis (TTGE), ARB, small subunit ribosomal RNA gene (SSU rRNA gene), alpine freshwater lake JOri XIII, PC
PRESERVATION OF GARUT RAMS SPERMATOZOON AS A SOURCE OF MALE GERM PLASM
Get PDFThis study was conducted to examine the quality of ejaculated sperm by Garut rams to be used for artificial insemination (AI) and viability of sperm that were collected from preserved cauda epididymis (4°C up to 12 days) for assisted reproductive technology. The semen was collected by artificial vagina, with the sperm motility, live sperm, acrosomal intact, and intact plasma membrane observed. Sperm motility was 75%, while for the live sperm, intact plasma membrane and sperm abnormality were 91.5%, 90.0%, and 1.8%, respectively. In the other study, sperm was collected from cauda epididymis by aspiration method and diluted in different media: 1) Brackett Oliphant (BO) media and 2) modified Phosphate Buffer Saline (mPBS). Evaluation of sperm motility and intact plasma membrane were conducted after washing, counting and dilution of the sperm. The results of this study showed that the sperm motility and intact plasma membrane could be maintained better in BO rather than PBS medium although they were not statistically different (P>0.05). At day 12 of preservation, the motility and intact plasma membrane of sperm collected from cauda epididymis were 0.7% and 1.33% for motility and plasma membrane intact, respectively. These findings showed that the Garut rams semen was qualified for AI and frozen processing; in vitro embryo production by introducing the assisted reproductive technology such as intracytoplasmic sperm injection (ICSI) could be applied by using the sperm collected from preserved cauda epididymis until 12 days of preservation at 4°C. Keywords :  Reproduction/spcrmatogenesis/inscmination/Garut rams/small ruminan
INFLUENCE OF MEVALONIC ACID AND LINALOOL ON LIMONENE ACCUMULATION IN CALLUS TISSUES OF CITRUS GRANDIS OSBECK
Get PDFEffect on callus growth was studied for Citrus grandis cultured with feeding of exogenous mevalonic acid (MVA) at concentrations of 0.04, 0.08, 0.38, 0.77, 1.15 and 1.54 mM. Similar effect with linalool ranging from 10 to 200 nl was studied under various incubation periods. The growth was proportional to the concentrations of precursors used meaning that higher precursors concentrations influenced more growth on C. grandis callus culture. Mevalonic acid and linalool showed quite similar precursor feeding effects on limonene accumulation of C. grandis callus cultures. It was revealed that limonene production was triggered with the introduction of MVA and linalool even at low concentration. Limonene accumulation was detected as early as week four and continued to increase at about 0.0030 and 0.0032 mg/g with MVA and linalool, respectively, after the seventh week incubation. In comparison to the unfed cultures, no limonene was detected from the callus up to eight weeks in incubation. Keywords :  C/rrusgrarafo/Limonene/Linalool/Mevalonic acid Abbreviations: 2,4-D: 2,4 — Dichlorophenoxyacetic acid, ABA: Abscisic acid, MVA : Mevalonic aci
PHYTOTOXICITY AND FIELD EFFICACY OF EXSEROHILUM LONGIROSTRA JC/MIN THE CONTROL OF BARNYARDGRASS ECOTYPES (ECHINOCHLOA CRUS-GALLI VAR. CRUS-GALLI(L.) BEAUV)
Get PDFFive selected ecotypes of bamyardgrass (Echinochloa crus-galli var. crus-gatti) from several rice growing areas in Malaysia and Indonesia were tested for their susceptibility to the potential bioherbicide (Exserohilum longirostratum). Bamyardgrass seedlings at the 2-3-lcaf stage were treated with 2.5xl07 conidia/ml from E. longirostratum at different application frequencies (single, double and triple). In addition, aqueous extract assays were evaluated for the presence of a phytotoxic compound responsible for the virulence of the bioherbicide. Results of the study showed that disease severity significantly increased 20 days after treatment and resulted in mortality of the seedlings. Ecotypes from Perak and Lampung were most susceptible to the bioherbicide upon triple applications. Percentage dry weight reductions were 86.34 and 83.14%, respectively. Other ecotypes (Melaka, Banten and South Sulawesi) were observed to have a relatively similar response. Moreover, aqueous extracts of E. longirostratum increased mortality up to 92.50% of bamyardgrass seedlings. These findings suggest that regular (double and triple) applications of E. longirostratum at a concentration of 2.5xl07 conidia/ml significantly increased mortality among bamyardgrass ecotypes. Mortality of the seedlings was attributed to the presence of a secondary phytotoxic metabolite. Key words :   Field efficacy / Phytotoxicity / Exserohilum longirostratum I Echinochloa crus-galli var. crusgalli I ecotypes
MORPHOLOGICAL VARIATION OF THE ECOTYPES OF Echinochloa crus-galli var crus-galli (L). Beauv (Barnyard grass: Poaceae) IN MALAYSIA and INDONESIA
Get PDFGreenhouse experiments were conducted to examine the morphological traits of barnyard grass ecotypes from diverse geographic origin. Seeds (caryopsis) were collected from 17 locations of rice fields throughout Malaysia (11 states) and Indonesia (six provinces) and were grown in pots each containing 10 kg of paddy field soil. The experiments were arranged using completely randomized design (CRD) with five replicates. Mean separation was calculated using Duncan multiple range test at 5% probability level. Unweighted pair-group method of arithmetic averages (UPGMA) was performed to determine the individual relationship within ecotypes of barnyard grass. Twelve morphological traits such as culm, panicle, leaf, and spikelet traits were measured. The growth characters such as emergence date, heading time, and growth duration were also evaluated. The average of emergence date, heading time, and growth duration of barnyard grass collected from Perils, Kedah, Penang, and Johor were relatively earlier than other ecotypes. Six groups were classified based on the cluster analysis of Malaysian ecotypes of barnyard grass. Principal component indicated that group six was found to be highly variable compared to others. While three groups were identified in Indonesian ecotypes of barnyard grass. Group one was observed to be highly variable. Results demonstrated that morphological variation among ecotypes of barnyard grass showing differences between the two regions illustrate the role of geographic variation. Key words : Variation / ecotypes / paddy field weeds / barnyard grass
PRELIMINARY STUDY ON THE PALM FLORA OF THE LORE LINDU NATIONAL PARK, CENTRAL SULAWESI, INDONESIA
Get PDFThe population size, structure, and composition of the palm flora in a 1350 m by 20 m rectangular plot in Gunung Potong and a 1500 m by 20 m rectangular plot in Tongoa were measured. The total palm species from both plots numbered 33 represented by 8 genera. Eight species, namely Calamus omatus var. celebicus, Pinanga caesia, Arenga pinnata, Daemonorops sp.3. Calamus didymocarpus. Calamus sp.4 (rapid spines), Caryota mitis, andAreca vestiaria have relatively high frequency values ranging from 5.46% to 10.66%. In addition, palm specimens previously collected from the park were examined at Herbarium Bogoriense to set up a preliminary checklist. So far, the national park is recorded as having 48 palm species represented by 11 genera which give figures of about 68% species and 58% genera of the total native Sulawesi palm flora. Though the number of endemic palms in Sulawesi is high (72%), namely 51 out of total native 71 species, only two species are locally endemic to Central Sulawesi namely Gronophyllum sarasinorum and Pinanga sp. nov. 1 (longirachilla). So far only the latter species is endemic to the national park. Key words: palm diversity/Lore Lindu National Park/Sulawesi/Indonesia/endemic specie
GENETIC DIVERSITY OF AMPICILLIN-RESISTANT Vibrio ISOLATED FROM VARIOUS STAGES OF TIGER SHRIMP LARVAE DEVELOPMENT
Get PDFThis research was carried out to study genetic diversity of ampicillin-resistant Vibrio from various stages of tiger shrimp larvae (Penaeus Monodon) development from,Tambak Inti Rakyat hatchery, near Labuan, West Java, Indonesia. A total of 25 ampicillin-resistant Vibrio isolates were isolated using thiosulphate citrate bile-salt sucrose agar (TCBS-Agar) and seawater complete agar (SWC-Agar). Physiological and biochemical characterization showed that the isolates could be grouped into only two species, i.e. V. harveyi from the egg stage; and V. metschnikovii from larvae and post-larval stage (i.e nauplius, zoea, mysis, PLi, PL5, PL,0, and PL,5). These isolates were also present in their respective rearing water of each stage and some natural feed. Schizotyping analysis employing restriction endonuclease Noll (5\u27-GC4GGCCGC) indicated that the isolates could be grouped into at least 13 different genotypes. Therefore, schizotyping was more discriminative than physiological characterization. This study showed that particular groups of Vibrio colonized all stages of shrimp larvae and demonstrated closed phylogenetic relationship. These groups of Vibrio might be the dominant microbiota which could suppress the development of other Vibrio including the pathogenic Vibrio. Key words : Shrimp/ampicillin-resistant K/fcno/schizotypin
SOIL QUALITY CHANGES FOLLOWING FOREST CLEARANCE IN BENGKULU, SUMATRA
Get PDFIntense destruction and degradation of tropical forests is recognized as one of the environmental threats and tragedies. These have increased the need to assess the effects of subsequent land-use following forest extraction on soil quality. Therefore, the objective of this study is to evaluate the impacts of land-use type on soil quality properties in Bengkulu Province, Sumatra. Soil samples were collected from adjacent sites including natural secondary forest, bare land, cultivated land and grassland. The results show that land-use following forest clearance lowered saturated hydraulic conductivity (85%), porosity (10.50%), soil water content at field capacity (34%),C organic (27%), N total (26%), inorganic N (37%), soil microbial biomass C (32%), mineralizable C (22%), and particulate organic matter (50%), but slightly increased water soluble organic C. Specific respiration activity rates increased about 14% in cultivated soils compared to natural forest soils, indicating greater C turnover per labile C pool in the form of soil microbial biomass, thus decreased biologically active soil organic matter. Forest conversion tends to reduce the C,ffg/Crer for all deforested sites. All of deforested areas relatively have infertile soil, with the worst case found in cultivated field. The C^g/Crd of cultivated fields was about 24% less than that of remnant forest (1.07). Grassland apparently maintains only slightly higher soil C levels than the bare land. On average, degradation index of soil following forest clearance was 35% with the highest deterioration occurred in the bare land (38%). Fallowing the fields by naturally growth of Imperata cylindrica for about 15 yr in abandoned land after 3-5 years of cultivation did not improve the soil quality. Moreover, forest clearance has an impact on soil quality as resulted in the loss of a physically protected organic matter and reduction in some labile C pools, thus declined biological activity at disturbed ecosystems. Keywords: Degradation index / forest / Imperata cylindrica grassland / soil quality/ soil organic matte
COMPATIBILITY STUDIES OF INTERSPECIFIC IN VITRO MICROGRAFTING OF AGARWOOD (Aquilaria malaccensis LAMK.)
Get PDFAquilaria spp produced agarwood as nonwood forest production, and has high economic value. A. malaccensis is susceptible to white rot diseases and termites. On the other hand most of the community plantations are a mixed culture with rubber trees, oil palms and with high risk of contamination causing white root diseases. Besides that, vegetative propagation by cuttings, stumping or air layering are still very difficult with low percentage of growth. The objectives of this research were to analyze the best suitable micrograft type, changes of SDS-PAGE protein band patterns of compatible and incompatible micrografts with several combinations of gaharu planlets in in vitro condition, and histology of union area between rootstocks and scion. The results showed that wedge or V type was the best of the micrografs. MS medium with the addition of 3 mg/L IBA was the best medium for gaharu planlet growth after micrografting. Acclimatization was conducted in husk chacoal and top soil (1:1) medium and grown under plastic house of 70% shading with paranet. Compatible combination (Ac/Am) of micrografting showed that anatomy structure of union area is the same as anatomy structure of non micrograftd planlet. While incompatible (Gv/Am) micrografting produced necrotic layer growth from pith and parenchymateous tissues of the wood in union area  along the middle of radial shoot. Recovery period of union area between stocks and scion is initiated by callus formation from the pith and parenchymatous tissues of the wood. Callus will differentiate into mature cells or tissue and become combined phloem and xylem vessels between rootstocks and scion. SDS-PAGE protein band pattern on compatible combination was the same as plants originated from seedlings. While, incompatible combination produced new protein bands with molecular weight around 21 and 30 kD.
Key words : Agarwood, Aquilaria spp, micrografting in vitro, incompatible micrografting, SDS-PAGE protein, incompatible histology
FISHERIES ASSOCIATED WITH MANGROVE ECOSYSTEM IN INDONESIA: A View from a Mangrove Ecologist
Get PDFBlessed with mangrove area of some 9.6 million ha in extent, Indonesia represents an important country with fishery resources being a source of food and nutrients. The fishery resources utilized by man, such as fishes, crustaceans and mollusks that are found in the mangrove ecosystem/swamp area arc enormous. There is a range of species caught in the mangrove and surrounding areas with over 70 species. However, commercially valued species are limited to a few such as rabbit fish, snapper, grouper, marline catfish, fringe-scale sardine, and anchovy. Leaf detritus from mangroves contribute a major energy input into fisheries. But information about the study on the relationship between fishery species and mangroves, ecologically and biologically, arc scanty. The mangrove is a physiographic unit, the principal components of which arc organisms. Therefore, the problems are predominantly of a biological nature (e.g., mangroves - fishery relationship). Positive correlation between the mangrove area and penaeid shrimp catch found in Indonesia, the Philippines, Australia and Mexico. Finally, the most important part of the variance of the MSY (Maximum Sustainable Yield) of penaieds (53% of the variance) could be explained by a combination of area of mangrove habitats and latitude. Keywords :  Indonesia/Mangrove/Ecosystem/Fisheries/Ecology/Coastal areas/Fishes/Molluscans/ Crustaceans