BIOTROPIA - The Southeast Asian Journal of Tropical Biology
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Elimination Of CVB (Chrysanthemum Virus B) From A Range Of ChrysanthemumTHE Varieties By Meristem Culture Following Antiviral and Heat Treatments
No full textCVB elimination for retaining healthy protocols from infected chrysanthemum plant was investigated trough combined treatment of meristem culture with synthetic antiviral ribavirin and thermotherapy under in vitro conditions. The biological material used on the experimentation was constituted of six commercial varieties: Dewi Sartika, Saraswati, Yellow Fiji, White Puma, Yellow Puma and White Reagent. Tissue culture initiation was conducted through plantlet establishment using MS supplemented with IAA. Ribavirin was added in media treatments with the concentration of 40 mg/l. Parallel with this step, heat treatment with different durations (1, 2, and 3 weeks) was also conducted on the plantlets. Meristem culture was done following the chemo- and thermotherapy. The experiment resumed the failure single treatment of meristem culture in eliminating CVB from the infected chrysanthemum plantlets. Under heat treatment, percentage of virus-free plantlets increased along with the duration of thermotherapy, though the survival rate of plantlets decreased in lengthened heat treatment. The best results regarding virus free plant percentage was obtained when meristem culture was applied following ribavirin or three weeks heat treatment which effectively eliminated virus particles from the plant
A SPECIES-SPECIFIC PCR ASSAY BASED ON THE INTERNAL TRANSCRIBED SPACER (ITS) REGIONS FOR IDENTIFICATION OF MYCOSPHAERELLA EUMUSAE, M. FIJIENSIS AND M. MUSICOLA ON BANANA
No full textA study on development of a rapid PCR-based detection method based on ITS region of M. eumusae, M. fijiensis, and M. musicola on banana was carried out. The main objecive of this study was to develop a fast and species-specific PCR-based detection method for the presence of Mycosphaerella species on banana. The methods include collection of specimens, morphological identification supported by molecular phylogenetic analysis, RFLP analysis, species-specific primers development, and validation. Two species of Mycosphaerella, namely, M. fijiensis and M. musicola, and one unidentified Pseudocercospora species were found in Java island. Three restriction enzymes used in the RFLP analysis, viz, AluI, HaeIII, and TaqI were capable to discriminate M. eumusae, M. fijiensis, and M. musicola. Two species-specific primer pairs, viz, MfijF/MfijR and MmusF/MmusR have been successfully developed to detect for the presence of M. fijiensis and M. musicola, respectively
PLANT COMMUNITY AND SOIL RELATIONSHIP FOLLOWING WILDFIRES FROM NUEES ARDENTES ON MT. MERAPI
No full textAt a local scale, vegetation patterns are known to have strong relationships with edaphic factors. In the case of Mt. Merapi volcanic eruption, studies on the relationships between edaphic factors and plant community composition and distribution following the nuees ardentes-ignited wildfires will provide valuable information on post-disturbance secondary successional processes. We collected soil and vegetation data from five different ages of nuees ardentes fire-affected secondary succession forests and one un-affected forest. Our results showed significant correlation of species composition and edaphic factors among sites of secondary forests. Nitrogen and soil water content were found to be the important factors in structuring species composition in the youngest site, where the N-fixing legume species such as Calliandra callothyrsus was found to be dominant. CCA ordination also revealed strong negative correlation between nitrogen content and legume group, while non-legume group were positively correlated with other edaphic factors such as phosphor and potassium. These findings suggested that changes in soil properties due to recovery of this system after volcanic eruption correlated with plant community composition and can be crucial factors in driving the successional trajectory. Understanding ecosystem reassembly process and trajectory of succession will improve how we approach the restoration of Mt. Merapi ecosystem
MOLECULAR IDENTIFICATION AND PHYLOGENETIC RELATIONSHIP AMONG LOCAL, SANGKURIANG, AND AFRICAN CATFISH BASED ON RAPD MARKER
No full textCatfish species are commercially cultivated freshwater fish by fish farmer. Formerly, only one species of catfish had been cultivated, namely local catfish (walking catfish) Clarias batrachus. However, since 1985, local catfish was replaced by a new commodity from Africa called African catfish (C. gariepinus). In 2004, BBPBAT Sukabumi had introduced a new strain of catfish, namely Sangkuriang catfish. Taxonomic analysis needed, especially for Sangkuriang catfish using molecular marker, in order to get a clearer picture about its genetics departure from their parental, so their taxonomic status and relationships with local and African catfish is clearer.  One of the molecular markers is randomly amplified polymorphic DNA (RAPD) markers. Species status defined based on the presence and absence of specific band on each catfish. Phylogenetics relationships was inferred from phylogenetic tree which was built using UPGMA tool as implemented in NTSYS software based on the similarity of RAPD band pattern. The result showed that Sangkuriang and local catfish had specific RAPD markers, while African catfish was not. This means that all RAPD markers of African catfish were shared with those of two others catfish. Local catfish phylogenetically distantly related to African and Sakuriang catfish. Only one individual of African catfish (D4) genetically close related to Sangkuriang catfish while the rest individuals of African catfish genetically closed related to green catfish. This means that African catfish showed very divergence genetic constituent.  Key words: catfish, molecular identification, phylogenetic relationships, RAP
SOIL WATER BALANCE, BIOMASS AND YIELD OF POTATO CROP (Solanum tuberosum L.) GROWN IN HIGH ALTITUDE HUMID TROPICS OF INDONESIA
No full textThis research calculated water loss through actual evapotranspiration and runoff (ETa+Ro) of potato crop in high altitude of humid tropics in Indonesia by using water balance approach. The treatments consist of two row spacings and three seed sizes for sowing. Soil water contents of six combination of treatments were measured weekly to the soil depth of 100 cm to calculate water loss by actual evapotranspiration and runoff. Water loss by ETa+Ro was much higher (average of 18.2 mm/day) compared to average potential evapotranspiration (7.5 mm/day). Despite high rainfall during the growing season (1314 mm), actual evapotranspiration could reduce soil water content to 60 cm soil depth due to the high runoff caused by limited capacity of water infiltration into the soil. Total ETa+Ro averaged for all treatments was 1365 mm which was comparable among treatments. Higher soil water content resulted in larger crop biomass and higher tuber yield. On the other hand, larger seed size produced greater crop biomass and tuber yield irrespective of the variation of soil water contents in the treatments
CONTRASTING ARBOREAL AND TERRESTRIAL BRYOPHYTES COMMUNITIES OF THE MOUNT HALIMUN SALAK NATIONAL PARK, WEST JAVA
Get PDFBryophyte communities were compared between arboreal (trunk bases) and terrestrialhabitats in primary forest Mount Halimun Salak National Park, West Java. The communitieswere analyzed based on species diversity, abundance, and biomass. A total of 150 bryophytesspecies were identified, including 67 species of mosses (Bryopsida) and 83 of liverworts(Hepaticopsida). Both bryophyte groups varied in diversity and abundance between arborealand terrestrial communities as well as among different elevations. Species diversity of arborealhabitats (116 species)was higher than that of terrestrial habitats (64 species). Moss speciesweremore abundant in terms of coverage in terrestrial habitats whereas liverworts species weremore abundant in arboreal habitats. Species richness in both terrestrial and arboreal habitatsdecreased towards higher elevation, whereas the abundance increased
INVASIVE GRASS IN INDONESIA: WHAT HAPPEN UP TO 2012? WITH COMPARISON OTHER INSTITUTION AND GOVERNMENT
No full textp { margin-bottom: 0.08in; } Invasive grass with dominant presence in ecosystem is often a neglected flora component. Meanwhile, the term “invasive†must be standardized, for practical purpose must be considered as urgent matter. Various attempts to compile invasive grass in Indonesia were conducted sporadically by several experts across generations. Scattered data along pile of literatures awaiting to be written in order to produce a comprehensive list of invasive grass. This paper represents the first attempt in drafting the invasive grass list of Indonesia by using literatures
DENGUE EARLY WARNING MODEL USING CLIMATE INFORMATION
Get PDFThe use of early warning system is potential adaptation options to reduce the impact of the climate variability and change. This study aims to develop a dengue early warning model using climate information. The model was developed through three steps of analysis. First step was to determine the length of periods used in prediction and optimal time for eradicating Aedes aegypti mosquito’s breeding sites. Second step was to identify the best prediction model of dengue incidence rate (IR). Third step was to develop an early warning model using stochastic spreadsheet.  It was found that the best predictors for predicting dengue incidence rate at week-n (IRn) were (1) rainfall index with two weeks lead time (ICHn-2). The rainfall index of week-nth is a function of three week moving averages rainfall (CH3), i.e. (CH3n-1.155*CH3n-1+0.702*CHn-2), and (2) IR with one week lead time (IRn-1). The IR model prediction was IRn = 0.795*IRn-1+0.067*ICHn-2 with R2=76.6%. These models (result model from first and third step) can be used to provide early warning on optimum time for controlling the mosquito’s breeding sites and the need for fogging action in order to avoid the dengue incidence rate beyond the critical limit defined by the Ministry of Healt
CHARACTERIZATION OF MALAYSIAN WILD BANANAS BASED ON ANTHOCYANINS
Get PDFThe male buds of 16 Musa species (Musaceae) populations were investigated by HPLC for the occurrence of anthocyanins. The investigation was based on the presence of 6 anthocyanins. The 16 Musa samples could be classified into three distinct species i.e. Musa acuminata, Musa violascens and Musa balbisiana. Musa acuminata could be divided into two subspecies : malaccensis (lowland) and tmncata (highland) according to their constituents and content of major anthocyanins. No variation was observed in the composition of the anthocyanins of Kedah type ssp. siamea and Selangor types ssp. malaccensis. The classification of M. acuminata into two subspecies based on anthocyanin data further supported the current taxonomic grouping of the species. Key words: Musa acuminata/Musa violascens/Musa balbisiana/Musaceae /HPLC /chemotaxonom
INDUCTION OF SPAWNING IN THE TROPICAL WALKING CATFISH (Clarias batrachus) BY CONTROLLING WATER LEVEL AND TEMPERATURE
Get PDFThis experiment was carried out to confirm the role of water level and water temperature in inducing the spawning of tropical walking catfish. Mature males and females reared under 23 - 25 °C, were paired and induced to spawn by controlling water level and water temperature. Decreasing water level and returning it to its original level resulted in a low spawning rate (less than 6.7 %) at 23 °C. Decreasing water level with simultaneous increase in water temperature, followed by returning the respective levels to their originals gave high spawning rates (41.7 — 50 %); whereas the same treatment but without any water temperature decreased when the water level was returned to the initial level, gave a low spawning rate (16.7 %). Increasing water level only, failed to induce spawning. A high spawning rate was obtained also when changes in water level were carried out under high temperature of 28 °C. No fish spawned in the absence of the environmental stimulation. From the results, it is confirmed that water level and temperature play important roles in inducing spawning of tropical walking catfish. Changes in water temperature probably increase the sensitivity of fish to the change in water level. Prolonged exposure to high water temperature could also improve the sensitivity of fish. Key words: Walking catfish / spawning / water level / water temperatur