BIOTROPIA - The Southeast Asian Journal of Tropical Biology
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INTRASPECIFIC VARIATIONS OF 16S MITOCHONDRIAL GENE SEQUENCES OF YELLOW RICE STEM BORER,scirpopbaga incertulas (LEPIDOPTERA: CRAMBIDAE) FROM WEST JAVA
No full textYellow rice stem borer (Scirpophaga incertulas) is one of the most important rice pest insects in Asia, including Indonesia. However, there is a lack of genetic data for this important agricultural insect. Â Therefore, this study was conducted to explore intraspecific differentiation of S. incertulas partial 16S mitochondrial gene from Bogor, Karawang, Indramayu and Cirebon (West Java, Indonesia). Here, we reported a total of 325 bp of 16S mitochondrial gene of S. incertulas from the obtained samples. Among all DNA sequences, three haplotypes of 16S mitochondrial gene were observed and submitted to GenBank under Accession Number of GU191881, GU191882, GU191883, respectively for haplotype 1, 2, and 3. Â The haplotype 1 was found in all S. incertulas surveyed locations, except Bogor. The haplotype 2 Â and 3 were found only in from Cirebon and Bogor samples. These haplotype variations can be applied as DNA markers for S. incertulas early larva detection method among other rice stem borers. Hence, further explorations of the mitochondrial variations of S. incertulas in Java and other parts of Indonesia are needed.
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Keywords: moth, haplotypes, genetic differentiations, Â molecular identificatio
STORED COCOA BEANS QUALITY AFFECTED BY FERMENTATION AND EPHESTIA CAUTELLA WALKER (LEPIDOPTERA: PHYCITIDAE) INFESTATION
Full text linkThe effects of fermentation on Ephestia cautella population and cocoa beans quality in terms of moisture content, fungal population, the percentage of insect-damaged and mouldy beans, lipid and free fatty acid contents during storage were investigated together with the effects of £. cautella infestation on the quality of stored cocoa beans and weight loss. Fermented and unfermented cocoa beans with initial moisture contents of 7 or 9% were placed in ventilated plastic jars (Ikg/jar) and stored for 6 months under room conditions. Seven larvae of £. cautella instar IV (2 males and 5 females) were introduced in each jar at the beginning of storage. Untreated jars contained only cocoa beans. Population of £. cautella on fermented cocoa beans with either initial moisture content of 7 or 9% was lower than that on unfermented beans during storage. The population either on fermented or unfermented cocoa beans with initial moisture content of 7% was lower than that of 9%, and the population of all treatments increased during storage. Moisture content of all treatments either on cocoa beans with initial moisture contents of 7 or 9% had the same pattern. The percentage of insect-damaged beans on fermented cocoa beans was lower than that on unfermented cocoa beans after 5 to 6 months of storage. The damaged beans on fermented cocoa after 6 months of storage was not different than on unfermented beans after 4 months of storage. The weight loss either on fermented or unfermented cocoa beans with initial moisture content of 9% was higher than that with initial moisture content of 7%. The weight loss on fermented cocoa beans either with moisture content of 7 or 9% was lower than that on unfermented beans during storage. The weight loss either on fermented or unfermented cocoa beans increased during storage. The percentage of mouldy beans on cocoa infested with £. cautella tended to increase during storage, while on beans not infested with the insect it fluctuated during storage. The highest percentage of mouldy beans was on unfermented and infested cocoa beans. Twenty-one fungal species were isolated from all treatments of cocoa beans during storage. The total fungal population on fermented and unfermented beans had the same pattern. The population on fermented cocoa beans was lower than that on unfermented beans. Total l ipid content on fermented cocoa beans either infested or not with £. cautella having initial moisture content of 7 or 9%, was lower than that of unfermented beans. The content either on fermented or unfermented cocoa beans and either infested or not decreased during storage. Free fatty acid content on cocoa beans infested with £. cautella was higher and significantly different than that on not infested. The content for both types increased during storage. Key Words :  Cocoa beans / Fermentation / Ephestia cautella I Moisture content / Fungal population / Insect-damaged beans / Mouldy beans / Lipid / Free fatty acid
LIPID PRODUCING MICROALGAE FROM SEVERAL ECOSYSTEMS IN WEST AND CENTRAL JAVA, INDONESIA
Full text linkThis study is aimed to get lipid producing microalgae as feedstock for biofuel production. The microalgae were isolated from 355 collected water samples which  represented many distinct ecosystems such as paddy fields, rivers, agricultural dams, ponds, swampy areas and unique ecosystem of volcano and mud-volcano craters in West- and Central Java, Indonesia. A total of  267 strains of microalgae were isolated from the samples of which  221 strains of them have capability to produce lipid. There were four promising strains that produce lipid between 14.7 – 45.7 percent dry weight in optimal condition that were identified as Chlamydomonas sp. KO-7267 and PK-7195, Chlorella sp. KS-7300 and Desmodesmus sp. BK-7291.
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Keywords: microalgae, lipid, biofuel, Indonesian ecosystem
COMPARISON OF THREE DIFFERENT TECHNIQUES OF GENE TRANSFER IN HUMPBACK GROUPER ( ) CROMILEPTES ALTIVELIS
Full text linkHumpback grouper is one of the most cultured fishes in Asia, including Indonesia. Themain problemfaced by humpback culture is its slow growth rate.One of themethods that willbe more effective and efficient to solve the problem is using transgenic technique. This studywas conducted to determine the effectiveness of transfection,microinjection and electroporationtechniques on gene transfer in humpback grouper. transfection was performed byincubating sperm to the foreign DNA (pktBP-ktGH gene construct)-transfectant complexsolution, while was by injecting those complex solution into testis of mature males.Microinjection was conducted in 2-4 cell stage embryos using 25 μg/ml of foreign DNAsolution, and duration of injection was 1, 2 and 3 seconds. Electroporation by 50 V, 30 ms ofpulse length, 5 of pulse number and 0.1 of pulse interval was performed to sperm using threeDNA concentration of 5, 10 and 20 μg/ml. The incorporation of foreign DNA in sperm andembryos were analyzed using PCR method. Based on PCR analysis, an optimum DNAconcentration for electroporation was 10 μg/ml. Limited number of embryos could bemicroinjected during 20-30 min to reach 2-4 cell stage. Microinjection for 1 second showedhigher survival rate of embryos, although none or very low number of larvae was hatched.Transfast was an effective DNA delivery reagent for humpback grouper sperm. Foreign DNAcould be detected in sperm from two out of ten transfected fish at least 36 hours posttransfection (hpt). By transfection, foreign DNA was detected in sperm at 48 hpt 25 Cincubation temperature. Our study revealed that transfection, microinjection as well aselectroporation could be used as transgenesis methods in humpback grouper. By means ofsimplicity and efficacy, however, electroporationwas an appropriate gene transfermethod.oIn vitroin vivoin vivoin vitr
MORPHOLOGICAL COMPARISON OF THREE ASIAN NATIVE HONEY BEES (APIS CERANA, A. DORSATA, A. FLOREA) IN NORTHERN VIETNAM AND THAILAND
Full text linkThree species of Asian native honey bees (Apis cerana, A. florea and A. dorsata) from northern Vietnam and Thailand were morphologically analyzed for investigations on their geographic variations and relations. In Vietnam, samples were collected from feral and managed colonies. In Thailand, the collections were from feral colonies or from field bees on flowers. Morphological analysis was carried out, using measurements common to honeybee taxonomy. Measured characters were done under stereomicroscope with an ocular micrometer. ANOVA program and multivariate statistical analyses were applied for treating the data. Overall, A. cerana populations in northern Vietnam are significantly morphologically different than from those in Thailand. It may be due to their different geographic locations between the Thai and Vietnamese populations of A. cerana. A. florea bees from Vietnam are generally bigger in size than those from Thailand, but the differences are uncertain. In contrast, the body size of A. dorsata populations from Thailand are bigger than those from Vietnam. However, these differences are also not significant. It is necessary to take further comparative investigations of these bee species from both countries. Key words: Honey bee/Apis cerana/Apis dorsata/ApisJlorea/moif>ho\og
NUTRIENT STOCKS IN FOUR STAGES OF A LOWLAND RAIN FOREST AT PASIRMAYANG, JAMBI, CENTRAL SUMATRA,
Full text linkStudies of nutrient cycling of tropical forests should differentiate between dynamic stages of the forest. We studied the nutrient concentration (N, P, K, Ca and Mg) and phytomass of aboveground (living and non living parts) and belowground compartments (soil) in four dynamic stages, namely Building (Bl and B2), and Mature (Ml and M2) stages, for a lowland rain forest. Nutrient concentrations in various compartments differed between the dynamic stages. Bark contains higher nutrient concentration than wood parts, both in stems and branches. Leaves contain higher nutrient concentration than wood parts, both in litterfall and litter. The concentration of K in throughfall is the highest, Ca and Mg perform similar value. Throughfall exhibits lower nutrient concentration than open area rain water. The nutrient concentration of 10-20 cm is higher than in the 0-10 cm soil depth. The phytomass values are highly variable among tree parts, diameter classes and dynamic stages. The phytomass is generally the highest in M2 and significantly different from Bl , Ml and B2. The phytomass of leaves in litterfall and litter is higher than wood parts. More litterfall and litter are accumulated in mature than building phases. Key words : nutrient / phytomass / dynamics / rain / fores
DIETARY EXPOSURE ASSESSMENT FOR AFLATOXIN B FROM PROCESSED PEANUT PRODUCTS IN MUNICIPALITY OF BOGOR 1
Full text linkA research on dietary exposure assessment for aflatoxin B (AFB1) fromprocessed peanutproducts in Municipality of Bogor was carried out. The objectives of this study were todetermine the contents of AFB1 in processed peanut products at retail levels, and to obtaininformation whether there is a risk to public health caused by the consumption of processedpeanut products contaminated by AFB1. Survey of processed peanut product consumptionwas carried out by interviewing each respondent using a questionnaire of weekly processedpeanut product consumption. Sampling of processed peanut products was conducted at thelocations where the respondents obtained processed peanut products. The number of roastedpeanuts with skin pods, flour-coated peanuts and or sauces samples was 33,respectively, while the number of and sauces samples was 18 and 12, respectively.The total number of processed peanut product sampleswas 129.AFB1contentwas determinedusingThin LayerChromatographymethod.Estimation of the dietary exposure assessmentwasdetermined using the actual survey data consisting of AFB1 content, consumption data andbody weight. The highest contaminated sample percentage and mean of AFB1 content wasfound in roasted peanuts with skin pods i.e. 42% of 33 samples and 43.2 μg/kg, respectively,followed by flour-coated peanuts (30% of 33 samples and 34.3 μg/kg), and or(21%of 33 samples and 17.1 μg/kg).Mean of estimated dietary exposure for AFB1 found inchildren was 15.2 ng kg bw day and 95 percentile exposure was 38.9 ng kg bw day , while inadults 9.0 ng kg bw day and 95 percentile exposure was 27.0 ng kg bw day . The excesscancer risk of AFB1 exposure in Bogor fromthis study on children and adults was calculated as193 and 115 cancers/year, respectively-1 -1 th -1 -1-1 -1 th -1 -1pecel gado-gadosiomay sataipecel gado-gado1
VEGETATIVE COMPATIBILITY GROUPS OF FUSARIUM OXYSPORUM, THE CAUSAL ORGANISM OF VASCULAR WILT ON ROSELLE IN MALAYSIA
Full text linkForty strains of Fusarium oxysporvm isolated from roselle (Hibiscus sabdariffa var. sabdariffa) showing vascular wilt symptoms in three states (Terengganu, Penang and Ipoh) in the northern Malaysian Peninsula were used to investigate the vegetative compatibility. Nitrate-nonutilizing (nil) mutants were recovered from all the strains tested and subsequently used to study vegetative compatibility groups (VCG) within the population by nit mutants pairings on minimal medium. Thirteen VCGs were found and none were vegetatively compatible with those of other formae speciales (f. spp.) such as asparagi and cubense, and non-pathogenic strains from paddy and oil palm. The results indicate that there is substantial genetic diversity in F. oxysporum that causes vascular wilt disease on roselle as reflected by multiple VCGs, but the distribution of strains into the VCGs is not even as there are 26 representatives in VCG-1001M, two in VCG-1003M and VCG-1013M and only one in the other VCGs. This study may provide new insight into the establishment of a new forma specialis off. oxysporum. Key words: Vegetative Compatibility Groups/M/ mutants/fitsarium oxysporwrn/Roselle/Vascular wilt/ Malaysia
RAPID DETECTION OF THE AFRICANIZED HONEY BEE: A TOOL FOR INDONESIAN ANIMAL QUARANTINE
Full text linkMolecular detection methods were used to determine if Africanized Honey Bees (AHBs) are present in populations of imported Apis mellifera in Indonesia. The cytochrome b (cyt b gene) was amplified from mitochondrial DNA and digested with the BglII restriction enzyme (cytb/BglII). Two types of animal DNA extraction kits were used and found suitable for rapid preparation of DNA from A. mellifera by the Animal Quarantine facility. Results showed that all 94 colony samples from beekeepers in Java produced a 485 bp PCR product from the amplification of this gene. Two DNA fragments of 194 and 291 bp from all samples were produced after digestion with BglII. This cytb/BglII result together with the DNA sequence of cyt b showed that all collected samples of A. mellifera were the non-AHB type. Hence, this study did not detect AHB in Indonesia.Key words :Â Apis mellifera, molecular detection methods, DNA, cytochrome b, mitochondrial genetic
The Effect of Initial Moisture Content, Packaging and Storage Period on Succinate Dehydrogenase and Cytochrome Oxidase Activity of Soybean Seed
Full text linkThe quality of soybean seed is easily decreased, so that it is difficult to keep them for a long time. The research aims to study the effect of initial moisture content, packaging material and storage period on succinate dehydrogenase and cytochrome oxidase activity. The experimental design was arranged in Factorial in RCB consisting of 3 factors: moisture content, i.e. 8. 10 and 12 percent, packaging materials, i.e. polyethylene, wheat and aluminium foil; storage period i.e. 0, 1, 2, 3, 4, 5, and 6 months. Changes in seed water content, specific activity of succinate and cytochrome oxidase, respiration rate, germination coefficient velocity germination, and abnormal seedlings were monthly determined. It was found that seed moisture content was increase and showed positive correlation with seed moisture content and abnormal seedlings and showed negative correlation with specific activity of succinate dehydrogenase and cytochrome oxidase, respiratory rate, germination and coefficient velocity germination. From this experiment, soybean seeds were stored in polyethylene and aluminium foil bags observed highly succinate dehydrogenase and cytochrome oxidase specific activity, respiration rate, germination, coefficient velocity germination and keep moisture content in low level could delay seed deterioration followed by polyethylene and wheat bags. Key words: moisture content, succinate dehydrogenase, cytochrome oxidase, soybea