BIOTROPIA - The Southeast Asian Journal of Tropical Biology
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QUALITY IMPROVEMENT OF DISQUALIFIED TIGER PRAWN (Penaeus monodon Fab.) BROODSTOCK USING DOPAMINE
Get PDFDisqualified tiger prawn broodstock is the one that has undergone ablation after two breeding periodes which causes high production cost pollution of environment and difficulties in providing it continuously with enough quantity at exact time The purpose of this study is to find the proper dosage of dopamine which will give good quality for breeding of the disqualified tiger prawn because dopamine inhibits maturation so it has enough time for maturation and can be improved the eggs quality
This experiment used 15 pairs the twice breeding tiger prawn which is taken from Perigi Central Java The sample were treated with difference dosage of dopamine dosage 109 108 107 106 moll and controlinjected by aquabidest The parameters were identified in this experiment are duration days for eggs maturation fecundity fertilizing rate hatching rate egg diameter and phototaxis respnnsive of the nauplii
The result of this research are the of the average of duration for eggs maturation on the broodstock that were injected dopamine dosage 109 108 107 106 moll and control were 14 12 4 2 5 days Fecundity 561489 503000 384205 230850 and 150034 Fertilizing rate 898 821 560 463 and 232 Hatching rate 7953 7253 4775 1227 and 366 Diameter 029 029 029 027 and 027mm The nauplii that had produced by injected broodstock by dosage 109 108 107 have the positive phototaxis responsive while dosage 106 and control were weak
Key words Disqualified dopamine dosage duration maturation fecundity fertilizing hatching diameters nauplii
V. PRELIMINARY STUDY ON ISOZYMES OF SHOREA JAVANICA
Get PDFThe detection of genetic variability in natural or man-made populations/ plantations is useful in both basic and applied biology. In addition to the various facets of studies on Shorea javanica already initiated by Torquebiau (1984) and alongside with his recommendations on focus for future research, a study on the genetic aspects of the species should be given important considerations. As the trees are tapped for resin, an important forest product, the genetic basis of the production as well as the range of variation in amount of resin production among the trees must be known. Coupled with this is a thorough investigation on the differences in pest resistance/susceptability among the trees and their genetic basis. While the assumption (Torquebiau 1984) that trees in natural forest areas are-rarely attacked by diseases because of mycorrhizal fungi is interesting, its confirmation is necessary. If this is true, problems would arise when plants are introduced into a new plantation site as experienced by the Forest Research Institute (Ardikoesuma 1954). Thus, we need to look for pest resistant plants i.e. those that can remain healthy even in the absence of mycorrhizae. The above studies on possible genetic variation could give vital information for development of forest plantations of the species and for breeding and tree improvement strategies. By knowing the extent of genetic variation in natural population or in plantations one could be guided to maintain or increase the genetic base in these areas. Biochemical characters such as isozyme banding patterns have been useful in several areas of plant biology, population genetics, evolution and breeding. Isozymes are detected by starch gel electrophoresis and when their genetic control is established, they could be genetic markers in analyzing variation in morphological or physiological characters. The present study is an attempt to detect the isozymes in leaves, seeds and cotyledons of Shorea javanica by gel electrophoresis
A COLLECTION OF TICKS (IXODIDAE) FROM SULAWESI UTARA, INDONESIA
Get PDFIxodid ticks were collected from seven species of endemic murid rodents and from vegetation in Sulawesi Utara, Indonesia. Adult ticks belonging to the species, Amblyomma babirussae, A. cyprium and Dermacentor (Indocentor) steini were taken from the vegetation. Immature ticks assignable to the genera, Haemaphysalis, Amblyomma and Ixodes infested the murids with Parauromys dominator and Maxomys musschenbroekii being the two most heavily tick-infested host species. The data are compared to other tick records from Sulawesi
REVIEW ON AFLATOXIN IN INDONESIAN FOOD- AND FEEDSTUFFS AND THEIR PRODUCTS
Get PDF Aflatoxin is a human carcinogen that could contaminate food- and feedstuffs, and hence is a major food quality problem throughout the world. Afiatoxin is produced by certain strains of AspergillusJlavus and //. parasiticus. A number of studies have been carried out in Indonesia on atlatoxin contamination in Indonesian food- and feedstuffs and their products from 1990 up to present. They were maize, maize product, peanuts, soybean and soybean meal, black and white pepper, feed ingredients; chicken and duck feeds. Samples were collected from farmers, traders (middlemen), retailers (markets), supermarkets, exporters; poultry and duck community-based farms; and feed mi l l industries. High levels of aflatoxins were often found in maize, peanuts, chicken feed derived from markets, and duck feed. Low levels of aflatoxins were found in soybean meal and chicken feedstuff. Aflatoxins were not detected in soybean, black and white pepper. Other studies have also been carried out on the effect of carbondioxide (CO2), phosphine, black pepper extract and antagonistic fungi on aflatoxin production of A. flavus in vitro\ and the effect of airtight storage, phosphine, ammonium hydroxide, fermentation process, bag types, and phosphine in combination with different bag types on atlatoxin contents of maize, peanuts and soybean meal. Some of these methods reduced aflatoxin contents significantly. Keywords: Aspergillus flavus I Aflatoxin / Food-and feed stuffs / Produc
RESPONSE OF TWO SUNFLOWER (HELIANTHUS ANNUUS L.) GENOTYPES TO VA-MYCORRHIZAL INOCULATION AND PHOSPHORUS LEVELS
Get PDFThe performance of two sunflower genotypes (Morden and MSFH-8) with and without VA-mycorrhizal fungi at three P levels (38, 56 and 75 kg P2O5 ha -1 ) in vertisol of Dharwad was studied to determine the effect of mycorrhizal inoculation on plant growth, yield and P uptake. The results showed that the VAM inoculation increased sunflower yield (14%), total biomass (16%), oil content (3.1%) and P uptake (30.5%) over uninoculated control. The percent root colonization and chlamydo-spore count decreased with increasing P levels. The total biomass production, seed yield and P uptake of mycorrhizal plants at 38 kg P2O5 ha -1 more than the non-mycorrhizal plants at 75 kg P2O5 ha -1 . The biomass and seed yield of mycorrhizal plants at same P level were more than the non-mycorrhizal plants. Mycorrhizal plants of Morden at 38 kg P2O5 ha -1 and MSFH-8 at 56 kg P2O5 ha -1 produced higher seed yield, oil content and total biomass than non-mycorrhizal plants supplied with 75 kg P2O5 ha -1 . The results indicated that, VA-mycorrhizal inoculation helps in saving 25 and 50 percent of recommended dose of phosphatic fertilizer (75 kg P2O5 ha -1 ) in MSFH-8 (single cross hybrid) and Morden (open pollinated variety), respectively.
Key words: Mycorrhizas/Plant nutrition/Inoculum/Glomus fasciculatum/Helianthus annuus/Phosphorus fertilizers/Metabolism
CRITICAL PERIOD OF MUNGBEAN (PHASEOLUS RADIATUS L.) TO WEED COMPETITION
Get PDFA field experiment was conducted to study the critical period of weed control on the crop of mungbean (Phaseolus radiatus L.). The studies were done in the field of BIOTROP Experimental Station with the natural existing weed population. It was found that the critical period of mungbean to weed competition was from 3-6 weeks after planting
THE EFFECTS OF DRYING AND SHELLING ON ASPERGILLUS FLAWS INFECTION AND AFLATOXIN PRODUCTION OF MAIZE*
Get PDFThe effects of drying and shelling on Aspergillus fla\-us infection and aflatoxin production of maize stored under laboratory conditions were investigated together with the intactness of grain and change of moisture content during the storage period. Fully matured maize var. Arjuna and CPI-2 were harvested at 90 and 97 days after planting, respectively, after which they were unhusked and divided into 4 pans. The 1st and the 2nd parts were sun dried up to 20^ moisture content (m.c.) and then shelled and re-dried up to 17 and 14% m.c.. respectively. The 3rd part was sun dried up to 17% m.c. and then shelled but not re-dned. The 4th pan was sun dried up to 17% m.c. and then shelled and re-dried up to 14% m.c. The maize was sun dried by spreading either the cobs or the kernels on the paved floor. The nail-down wood and mechanical sheller were used for shelling the maize. After drying and shelling, maize samples were stored in the jars which were covered with muslin cloth for 3 months under laboratory conditions. A. flavus was isolated using dilution method on Aspergillus Flavus and Parasiticus Agar (AFPA). The damaged kernel analysis was carried out at the beginning of storage to obtain the percentage of damaged kernel caused by shelling. The m.c. and aflatoxin were determined using oven and High Performance Liquid Chromatography (HPLC) methods, respectively. The m.c. decreased at 1 month of storage and then it was almost constant at 2 and 3 months of storage. The percentage of damaged kernels of maize var. CPI-2 was higher than those of var. Arjuna. The percentage of damaged kernels of maize shelled at 20% m.c. was higher than that shelled at 17% m.c. The percentage of damaged kernels of maize shelled by mechanical sheller was higher than that shelled by nail-down wood.*Paper presented at the Symposium on Pest Management for Stored Food and Feed, 5 -7 September 1995 Bogor, Indonesia
CLONING OF A GENE ENCODING PROTEIN BELONGING TO ABC TRANSPORTER INVOLVED IN BACTERIAL MAGNETIC PARTICLE SYNTHESIS IN MAGNETOSPIRILLUM MAGNETICUM AMB-1
Get PDFMagnetospirillum magneticum AMB-1 synthesizes intracellular magnetic particles, magnetite (Fe3O4), enveloped by membrane called magnetosome under micro-aerobic conditions. Initial study of random transposon-based mutagenesis generated 62 nonmagnetic mutants of AMB-1 in a mini-Tn5 library. In order to identify a gene involved in bacterial magnetic particle (BMP) synthesis in the magnetic bacterium M. magneticum AMB-1, a nonmagnetic mutant from the library designated as NMA38-4, was analyzed. h e amino acid sequence deduced from the gene directly interrupted by transposon, ORF4 (1482 bp), showed homology to ATP binding cassette (ABC) transporter of Mesorhizobium loti with 62 % identity and 74 % similarity. It was strongly indicated by the occurrence of putative consensus sequence of ATP-binding motifs (ATP-binding protein). h e ORF4 was subsequently cloned in pET-15b and the recombinant ORF4-Histag fusion protein was heterologously expressed in Escherichia coli BL21 (DE3) pLysS. A 55 kDa protein corresponding to the ORF4-Histag fusion protein was obtained after puriï¬ cation using Ni-NTA column. h is is the ï¬ rst report describing a gene cluster containing gene encoding protein belonging to ABC transporter organized in an operon which is involved in BMP synthesis. Key words: Magnetospirillum magneticum AMB-1, Bacterial Magnetic Particle (BMP), ATP Binding Cassette (ABC) Transporter, transposon mutagenesis
SPATIAL DISTRIBUTION OF INVASIVE PLANTS IN BANDUNG, WEST JAVA, INDONESIA
Get PDFThe urban area is a source of invasive plants that enter through human activities such as agriculture and land-use conversion. Studying the invasive plant in urban areas is essential to understanding the city’s ecosystem health condition. Therefore, this study aims to inventory invasive plants, map their distribution, and explain the relationship between land use with the community diversity and species richness of invasive plants in Bandung. The vegetation analysis was performed using line-transect in 22 study sites distributed using a systematic random sampling method in Bandung to observe the plant species composition. The study plots were placed based on the land-use type. The species name, individual number, frequency, and sampling site locations were noted and analyzed to calculate the important value index (IVI) and the invasive species distribution pattern using the principal component analysis (PCA). The dominant invasive species was spatially mapped. Six types of land use were used in this study, i.e., settlements, street green lanes, gardens, paddy fields, urban parks, and urban forests. There were 187 species found in Bandung, which can be categorized into alien invasive species (39%), invasive native plants (25%), non-invasive alien species (18%), non-invasive native species (15%), and unidentified plants (3%). The most common invasive plants found were Eleusine indica (IVI=10.50%), Trimezia martinicensis (IVI=7.22%), and Cyperus rotundus (IVI=6.74%). Based on the plant community similarity index, the study area with the highest similarities were paddy fields with gardens (50.5%), settlements with road lanes (44.4%), urban parks with road lanes (26.2%), and urban forests with road lane (17.5%). PCA showed Swietenia macrophylla as the most common invasive plant found in urban forests, urban parks, and road lanes, with air humidity as the most influencing environmental factor. Trimezia martinicensis is the most common species in the settlement area affected by high air humidity. Bidens pilosa is an invasive plant commonly found on paddy fields, gardens, settlements, road lanes, and urban park edges. This species can easily and rapidly reproduce with a high survival rate. The many invasive plants found in Bandung must be managed to maintain the urban ecosystem’s health
INDIGENOUS BACILLUS SPECIES ISOLATED FROM AEDES AEGYPTI LARVAE: ISOLATION, LARVICIDAL TOXICITY SCREENING, PHENOTYPIC CHARACTERIZATION, AND MOLECULAR IDENTIFICATION
Get PDFVector-borne diseases transmitted by mosquitoes are considered a significant public health problem worldwide. Aedes aegypti is one of the mosquito species responsible for transmitting these diseases. One environmentally friendly method of vector control is the use of microbial agents such as Bacillus species. This study aimed to explore investigate indigenous entomopathogenic bacteria of Bacillus species isolated from A. aegypti larvae. Larvae samples were collected from breeding sites of A. aegypti. All isolates underwent screening and affirmation confirmation tests to assess their larvicidal toxicity against A. aegypti larvae. Phenotypic characterizations and molecular identifications were conducted to determine the species of the Bacillus isolates based on similarity index and percent identity (%ID). Phylogenetic trees were used to compare the isolates with other Bacillus species. The results revealed 120 isolates of Bacillus species from A. aegypti larvae samples. Among them, three isolates (LS3.3, LS9.1, and LSD4.2) exhibited the highest larvicidal toxicity in the confirmation test, resulting in larval mortality rates of 100%, 96.7%, and 100%, respectively, after 48 hours of exposure. Molecular identifications, showed that LSD4.2 had a 99.16% ID with Bacillus velezensis, LS3.3 had a 98.22% ID with Bacillus mojavensis, and LS9.1 had a 99.93% ID with Bacillus subtilis. These three bacteria from the Bacillus genus have been reported to offer significant benefits to humans