BIOTROPIA - The Southeast Asian Journal of Tropical Biology
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GROWTH AND DEVELOPMENT OF Fimbristylis miliacea (L.)Vahl
Get PDFoai:ojs.journal.biotrop.org:article/1This experiment was conducted in the glasshouse of Universiti Putra Malaysia, to determine the growth and development of Fimbristylis miliacea (L.) Vahl. Twenty F. miliacea seeds were surface sown in ten plastic buckets of 18 cm diameter filled with 3 kg soil. After germination only one plant/bucket was retained. Time of first seedling emergence, time and number of leaves appearing until first tiller formation, time of tiller formation, first inflorescence, the first 10 inflorescences appearance and their maturity were recorded for each plant. Plant height and the number of inflorescence per plant was recorded weekly for up to 4 months after sowing. The first ten inflorescences for each plant were tagged after emergence, subsequently mature inflorescences were collected and the numbers of spikelets/inflorescence, seeds/inflorescence, seeds/ plant and 1000 seed weight were determined. Statistical analysis was performed as complete randomized design on weekly observed plant height and inflorescence number using the SAS statistical software and means were tested using Tukey’s studentized range test at the 5% level of probability. Fimbristylis miliacea seedlings emerged at 3 days after planting of seeds. Approximate times required for the sequential production of 10 leaves, tillers, first 10 inflorescence and their maturity were 28 days after emergence (DAE), 35 DAE, 49 DAE, 63 DAE, respectively. Plant height increased rapidly from 3-8 WAE and maximum plant height (64.05 cm) was attained at 10 WAE. This species had three important growth stages: a slow growth stage during the first 4 week after emergence (WAE); a rapid growth stage from 4-9 WAE; and finally, a maximum growth stage from 9-17 WAE. Within this first 4 weeks after emergence would be the most appropriate time for controlling this species with early post emergence herbicides. Each F. miliacea plant produced on average of 2.3 tillers/plant and a total of 134 inflorescences, with 84 inflorescences/plant ripening within this period. Each inflorescence comprised of 48 spikelets with 511 seeds and matured after 3 weeks of emergence. Total seeds/plant and 1000 seed weight were 42,275 and 0.035 g, respectively. Time required for seed ripening was 76 days after emergence
SACCHARIFICATION OF CORNCOB USING CELLULOLYTIC BACTERIA FOR BIOETHANOL PRODUCTION
Get PDFThe use of cellulose degrading enzyme (cellulases) for hydrolysis of lignocellulosic material is a part of bioethanol production process. In this experiment,  delignified corncob, its cellulose fraction and alpha cellulose were used as substrates to produce fermentable sugar by using three local isolates of celluloytic bacteria (C5-1, C4-4, C11-1 and Cmix ; mixed cultures of three isolates), and Saccharomyces cereviseae to produce ethanol. The results showed that all isolates of cellulolytic bacteria can grow on cellulose fraction better than on  delignified corncob, and alpha cellulose. The highest hydrolytic activity produced from cellulose fraction was by isolate C4-4, which liberated 3.50 g/l of total sugar. Ethanol can be produced by mixed culture of bacteria and yeast, but because of competitive growth, the fermentation only produced 0.39-0.47 g/l of ethanol.
Keywords:Â Celluloses, delignified cornco
SOURCES OF MYCORRHIZAL INFECTION OF SHOREA ACUMINATA SEEDLINGS UNDER LABORATORY CONDITIONS*)
Get PDFUninoculated dipterocarp seedlings raised in normal field soil in nurseries were always found to have mycorrhizas after a few months. This study set out to determine whether dipterocarp seedlings could continue to grow and develop in the absence of mycorrhizas and also to determine possible sources of mycorrhizal infection of dipterocarp seedlings raised under laboratory conditions using Shorea acuminata as a typical example. Seedlings were planted in capped or uncapped perspex boxes containing sterile or non-sterile field soil and watered daily with sterile water or tap water. Seedling growth and development of mycorrhizas were monitored at monthly intervals for up to seven months. Seedlings grown in sterile soil remained uninfected after seven months while infection was found in some of the seedlings grown in normal soil regardless of whether they had been watered with tap water or sterile water. This showed that field soil (i.e. under grass) far from the forest contained suitable inoculum for forest tree seedlings. Tap water and the air were not important sources of infection. However, mycorrhizal infection was very uneven indicating that the inoculum was probably very unevenly distributed in the soil or that the inoculum density was rather low. Seedlings grown in sterile soil showed better growth than those grown in normal soil and infection of roots by parasitic fungi in the latter was also observed.
Key words: Mycorrhizas/Plant pathology/lnfections/Shorea acuminata/Seedlings
EXOPOLYSACCHARIDE PRODUCTION AND ITS BIOACTIVITIES OF THE EDIBLE PLEUROTUS OSTREATUS IN SUBMERGED CULTURE
Get PDFSubmerged cultures were used to study the influence of various carbon sources on the mycelial biomass and exopolysaccharide production of Pleurotus ostreatus. The antimicrobial and antioxidant activity of  the exopolysaccharide were also determined.  The yield of mycelial biomass of 7.06 g/l, 5.12 g/l, 4.66 g/l, and 2.96 g/l was obtained by utilization of maltose, glucose, lactose and starch as a carbon source, respectively. Furthermore, in the medium containing maltose, lactose, glucose, and starch produce 100.05 mg/l, 97.73 mg/l, 78.63 mg/l, and 70.45 mg/l of exopolysaccharide, respectively. The assay of antimicrobial and antioxidant activity showed that the exopolysaccharide is more active to inhibit the growth of B. subtilis rather than those of E. coli and S. cerevisiae. Furthermore, the exopolysaccharide was also indicated to have antioxidant activity.Key words: Pleurotus ostreatus, exopolysaccharide, antimicrobial activity, antioxidant activityÂ
EMBRYO RECONSTRUCTION BY TRANSPLANTATION OF THE DONOR INNER CELL MASS TO THE RECIPIENT BOVINE BLASTOCYST
Get PDFIn an attempt to produce the interspecies embryo transfer, this study was conducted to evaluate the efficacy of the production of reconstructed blastocyst by transferring the donor ICM into the recipient trophoblast. ICM cells were isolated from the donor blastocyst by immunosurgery method. Zona-free blastocysts were incubated in the medium (TCM-199) containing 20% of the heat-inactivated rabbit anti-bovine-serum. The embryo reconstruction was produced by three different methods. Recipient blastocyst was maintained on the holding pipette by gentle suction, with the ICM in a 9 o\u27clock position to have the possibility of developing incorporate ICMs (Method I), the ICM was in a 3 o\u27clock position to break the original ICM during injection (Method 2); cutting the original recipient ICM followed by insertion of the donor ICM (Method 3). Reconstructed blastocysts were then cultured overnight and examined morphologically according to the re-expansion of the reconstructed blastocyst with or without developed donor ICM. According to morphological observation in this study, 37.9% of the reconstructed blastocyst developed with the incorporation of two ICM originally from recipient and donor (Method I), 66.7% of the reconstructed blastocysts developed with a single ICM (Method 2), and 80.0% of the reconstructed blastocyst developed from the ICM originally from donor ICM (Method 3). These results showed that the reconstructed blastocyst is better produced by cutting the original recipient ICM followed by the insertion of the donor ICM (Method 3).Key words: embryo reconstruction, immunosurgery, ICM transfer, bovine
EFFECTS OF SOIL STERILIZATION ON THE FORMATION AND FUNCTION OF TWO STRAINS OF PISOLITHUS TINCTORIUS ON EUCALYPTUS UROPHYLLA*)
Get PDFTo examine the effects of soil microbial population on mycorrhizal development and function, Eucalyptus urophylla seedlings were inoculated with two Pisolithus tinctorius isolates and grown in sterile, partly sterile and non-sterile soil. The two isolates of Pisolithus were an effective isolate (H445) collected from under eucalypts in Australia and an isolate (H615) collected from under eucalypts in the Philippines. Soils used were infertile acid soils collected from field sites in Pangasinan, Luzon and Surigao, Mindanao. In both soils, the Australian Pisolithus H445 improved the growth of E. urophylla seedlings more than Philippine isolate H615. The uninoculated seedlings exhibited stunted growth typical of P deficiency. Height at 8 weeks was significantly taller in sterile than in non-sterile soil. A significant interaction effect of inoculation and soil sterilization on height at harvest was observed only in Surigao soil. Soil sterilization had a varied effect on mycorrhizal formation. In Pangasinan soil, root colonization by H445 was significantly greater in non-sterile soil than in sterile soil. Whereas in Surigao soil, root colonization was significantly reduced by 54% from partly sterile to non-sterile soil. On the other hand, H615 showed significant mycorrhizal colonization in non-sterile soil compared from those in partly sterile and sterile soils. The degree of infection did not necessarily correspond to growth promotion in E. urophylla seedlings. These results indicate that the performance of the H445 was markedly affected by the microbial flora of the two soils. Thus, its potential use in the Philippines needs to be thoroughly tested in the field before its widespread use in any inoculation program.
Key words: Pisolithus tinctorius/Laccaria fraterna/Pinus patula/Inoculum/Seedlings/Growth
NATURAL PRODUCTS IN ORGANIC SYNTHESIS
Get PDFA resume of four lectures presented by the author during a one month visit to BIOTROP in 1995. The seminars were held at the University of Indonesia at Depok, the Technical Institute in Bandung, the Bogor Agricultural Institute and at BIOTROP, Bogor. The talks were grouped under the general title "The Use of Natural Products in Organic Synthesis".
Key words: Organic compounds/Natural products
INTEGRATED USE OF NEOCHETINA BRUCHI AND ALTERNARIA EICHHORNIAE IN CONTROLLING WATER HYACINTH
Get PDFThe study on the integrated use of the chevroned water hyacinth weevil (Neochetina bruchi Mustache) and the water hyacinth blight disease (Alternaria eichhorniae Nag Raj & Ponnappa) in suppressing water hyacinth growth was carried out under field conditions at Situ Bagendit lake, Garut, West Java. The objectives of this study were (I) to investigate whether the combined use of the two control agents produced a better effect in suppressing water hyacinth growth, (ii) to evaluate whether there is a change in oviposition and feeding habit of the chevroned water hyacinth weevil if the water hyacinth is seriously infected by A. eichhorniae, and (iii) to evaluate the progress of weevil establishment in the field. The following results were obtained:(1) The concentration of Tween 80 which did not interfere with spore germination was 3%.(2) There was no difference between distilled water and 1% Potato Dextrose Broth (PDB) as a medium for fungal spores production.(3) The combined use of chevroned water hyacinth weevil and the water hyacinth blight produces a better suppressing on water hyacinth growth.(4) There was no significant effect of heavy infection by the water hyacinth blight on oviposition habit of chevroned water hyacinth weevil. Heavy fungal infection only affected feeding habit of the adult chevroned water hyacinth weevil.(5) Establishment of the chevroned water hyacinth weevil is in progress at Situ Bagendit lake, Garut regency, West Java
The POTENTIAL OF LACTIC ACID BACTERIA, ISOLATED FROM SEVERAL SOURCES, TO INHIBIT THE GROWTH OF Candida albicans ATCC10231
No full textARTICLE HIGHLIGHTS- Lactic acid bacteria have potential to control candidiasis or Candida albicans. - The novelty of this study is to advance the potential of lactic acid bacteria to control candidiasis infection in human, with a view to develop novel LAB-based probiotic candidates with capability to inhibit/prevent infection by C. albicans, the causative agent of candidiasis.ABSTRACTThe main aims of this research were to isolate and identify potential lactic acid bacteria (LAB) inhibitory to Candida albicans. The LAB sources were kimchi, honey and vaginal secrete of healthy women. They were isolated with a view to develop a novel alternative method with reduced use of antifungal agents in the treatment of patients infected by such fungal pathogen. Isolation of the LABs was conducted by applying dilution spread method on de Mann Rogosa Sharpe agar (MRSA) medium supplemented with bromo cresol purple (BCP) indicator. Once purified, they were tested for antagonism against C. albicans in dual culture assays. LAB isolates that showed significant inhibition against the pathogen were identified using 16s rDNA sequences and their sequences were aligned with those of known sequences deposited at the Gene Bank (http://www.ncbi.nlm.nih.gov). The results showed that 46 among more than 100 LABs isolated in this study significantly inhibited the growth of C. albicans in the in vitro dual culture assays, and all showed resistance property to antifungal agent (fluconazole). This indicated that they all have potential to be synergically applied with reduced use of fluconazole in the therapy. The most potential isolates (10 isolates) were closely related to three LAB species, namely Lactobacillus paracasei, Lacticaseibacillus paracasei, and Pediococcus pentosaceus, based on their 16s rDNA sequence similarities with those deposited in the GenBank
A NEW SPECIES OF THE Odontomachus infandus SPECIES GROUP (HYMENOPTERA: FORMICIDAE) FROM PANGASINAN, PHILIPPINES, WITH NOTES ON SPECIES ECOLOGY
Get PDFARTICLE HIGLIGHTS- New species of Odontomachus- Distribution and ecological notes- Updated species key
ABSTRACTA new species of Odontomachus Latreille, 1804 named O. ampipitbaybay sp. nov. is illustrated and described from specimens collected along the coastal area of Alaminos City, Pangasinan, Luzon Island, Philippines, with notes on its species ecology. The new species is diagnosed and compared against closely related species from Luzon. A distribution map of selected Philippine Odontomachus species is provided, and a modification to the key to the Philippine Odontomachus is proposed