BIOTROPIA - The Southeast Asian Journal of Tropical Biology
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THE EFFECTS OF MILLING DEGREE AND TYPE OF BAG ON FUNGAL INFECTION AND SOME CHEMICAL CONTENTS OF STORED MILLED RICE
Full text linkThe effects of milling degree and type of bag on fungal infection of stored milled rice were investigated together with some chemical contents (glucose, amylose, protein and total lipid contents), and changes in moisture content. Rice var. IR 64 with different milling degrees (85, 90, 95 and 100%) packed in jute and polypropylene bags (1 kg of milled rice/bag) were stored under laboratory conditions with temperature between 24.3-27.3 C and relative humidity 52.6-81.9% for 3 months. The initial moisture content (m.c.) of milled rice was ± 14%. Three replications (3 bags) were used for each treatment. Each bag was put individually and was arranged randomly on a wooden pallet. The results showed that in general, the increase of milling degree and duration of storage decreased the m.c. Type of bag did not give significant differences on the m.c. Twenty eight fungal species were isolated from rice with different milling degree and bag type during storage. The predominant species was Aspergillus Candidas. Total fungal population decreased with the increase of milling degree and duration of storage. Bag type did not give significant differences on total fungal population. In general, the increase of milling degree increased glucose content. Glucose content in milled rice packed in jute bag was higher than that in polypropylene bag. Glucose content tended to decrease with the increase of storage duration. The increase of milling degree increased amylose content in milled rice. Amylose content of milled rice packed in jute bag was lower than that in polypropylene bag. The increase of storage duration decreased amylose content in milled rice. In general, protein content decreased with the increase of milling degree and duration of storage. 1 type did not give significant differences on protein content. Total lipid content decreased with the increase of milling degree and duration of storage. Total lipid content of milled rice packed in jute bag was lower than that in polypropylene bag, but based on chemical analysis the difference was not significant. Based on statistical analyses, correlation between the m.c. and total lipid content with total fungal population was positive. There was no correlation between glucose, amylose and protein contents with total fungal population. Rice with high milling degree can be stored safely for long period, but it has low chemical (nutritional) contents. Key words:  Milling degree/Bag type/Fungal infection/Chemical content/Milled rice
ISOLATION AND CLONING OF cDNA OF GENE ENCODING FOR METALLOTHIONEIN TYPE 2 FROM MELASTOMA AFFINE
Full text linkMetallothionein is an important protein for detoxifying heavy metal ions. This research was conducted to isolate and clone cDNA of gene encoding for metallothionein type 2 from Melastoma affine. Total RNA was isolated from young leaves. Total cDNA was synthesized from the total RNA by reverse transcription. The MaMt2 cDNA was successfully isolated by PCR technique. The MaMt2 cDNA was inserted into pGEM-T Easy and the recombinant plasmid was successfully introduced into Escherichia coli DH5α. DNA sequencing analysis showed that this cDNA is full length consisting of 246 pb encoding 81 amino acid residues. This cDNA is identical to mRNA of AtMt2 from Arabidopsis thaliana. It does not contain any restriction sites found in the cloning sites of pGEM-T easy. The deduced protein of MaMT2 contains 14 cysteine residues distributed in the Cys-Cys, Cys-X-Cys, and Cys-X-X-Cys motifs.  Key words: cDNA, metallothionein, Melastoma affine, cloning, cystein
GROWTH INHIBITION OF PATHOGENIC ROOT FUNGI BY EXTRACTS OF ECTOMYCORRHIZAL FUNGI OR Picea glehnii INOCULATED WITH ECTOMYCORRHIZAL FUNGI*
Full text linkThis work sought to verify the presence of compounds with antimicrobial properties in extracts of ectomycorrhizal fungi or in Picea glehnii inoculated with ectomycorrhizal fungi. Extracts from Pisolithus tinctorius, Scleroderma flavidum, Amanita pantherina and Paxillus sp., grown in liquid culture media, and from P. glehnii seedlings inoculated or not with the above ectomycorrhizal fungi and cultivated in in vitro condition, were processed to obtain two fractions, water and ethyl acetate solubles. These fractions were tested for the presence of inhibitory constituents against Fusarium roseum, Pythium sp. and Rhizoctonia solani. Direct bioautography technique on TLC or paper disc technique was used, depending on the extract and pathogenic fungi tested. The results showed the production on inhibitory components, not only by ectomycorrhizal fungi, but also by P. glehnii inoculated or not with ectomycorrhizal fungi. The sensitivity varied considerably according to the type of fungus or extract.
Key words: Japan/Mycorrhizas/Inh|bition/Extracts/Antimicrobial compounds/Amanita pantherina/Pisolithustinctorius/Paxillvs spJScleroderma flavidum/Fusarium roseum/Pythium spJRhizoctonia solani.
NOTES ON THE FAMILY AMPULLARIIDAE (GASTROPODA: PROSOBRANCHIA) IN THE PHILIPPINES: I. DIGESTIVE, CIRCULATORY, AND EXCRETORY SYSTEMS
Full text linkA total of 232 ampullariid snails collected from 23 sites covering 7 islands in the Philippines were compared conchologically and 200 alcohol-preserved specimens were dissected for anatomical characteristics. Conchological comparison of the shells of the collected snails with that of identified lots from the Senckenberg Natur-museum, Frankfurt, Germany, the British Museum for Natural History, London, England, the Koninklijk Belgisch Instituut voor Natuurwetenschappen, Brussels, Belgium, and the Rijksmuseum voor Natuurwetenschappen, Leiden, Netherlands, revealed the presence of 5 species in the collected samples. These are: P. conica, P. ampullacea, P. mainitensis, P. quadrasi, and P. vittala. The latter 3 species were previously reported as being indigenous to the Philippines. Aside from characteristics of the shell, the morphology of the stomach may be useful for species discrimination. P. quadrasi and P. vittata, however, do not seem to differ anatomically from P. conica
THE EFFECTS OF a-CHLOROHYDRIN ON THE GESTATION OF THE WISTAR RAT (Rattus norvegicus)
Full text linkThe investigation of the effects of a-chlorohydrin on the gestation of the wistar rat has been carried out to determine whether a-chlorohydrin could interfere with the gestation of the rat and gestation period for optimal sensitivity. Alpha-chlorohydrin was administered by gavage to three different groups of pregnant rats, namely on the first (pre-implantation period), sixth (early post-implantation period) or fourteenth (late post-implantation period) gestation day, at a single dose of 62.5; 75 and 90 mg/kg body weight. Rats were sacrificed on the IS* gestation day. Number of implantations, gestation loss and post-implantation mortality were recorded. The results revealed that 75 and 90 mg/kg body weight of a-chlorohydrin significantly interfered with all the gestation periods used. For the pre-implantation group, a-chlorohydrin decreased significantly the implantation number, but increased the gestation loss as well as the post-implantation mortality compared to the control groups. For the early post-implantation and late post-implantation groups, a-chlorohydrin caused a significant increase in post-implantation mortality compared to the control groups. From these results it is concluded that a-chlorohydrin at 75 and 90 mg/kg body weight influences the gestation of the wistar rat administered during the pre-implantation period as the most sensitive gestation period. Key words : a-chlorohydrin//tattu? norvegi\u27ctu/rat/pre-implantation/early post-implantation/late post-implantation/implantation/gestation loss/post-implantation mortality
MYCORRHIZAE IN AGROFORESTRY: A CASE-STUDY
Full text linkCensus of mycorrhizae in Shorea javanica agroforests has been made periodically in the district of Krui, Lampung, Sumatra. Amanita hemibapha (Amanitaceae), Cantharellus cibarius (Cantharella-ceae), Lactarius spp., Russula spp. (Russulaceae) and Scleroderma sp. (Sclerodermataceae) were commonly encountered on the agroforest floor. These mycorrhizal fungi are naturally associated with the planted trees. The significance of mycorrhizae for the maximization of growth and sustained productivity of resin is discussed as well as the need to design well defined agroforestry systems to facilitate growth and to improve production management techniques
EFFECTS OF VARIOUS SOIL ENVIRONMENTAL STRESSES ON THE OCCURRENCE, DISTRIBUTION AND EFFECTIVENESS OF VA MYCORRHIZAE
Full text linkThe vesicular - arbuscular (VA) mycorrhizal fungi are geographically ubiquitous soil inhabitants and form universal symbiotic relationship with plants from every phylum. These fungi link host plants with host soils and their biota in the mycorrhizosphere and play an important role in plant health, productivity and soil structure. Although VA mycorrhizal fungi do not show any host specificity, there is increasing evidence that various climatic and edaphic environmental factors such as land use and management practices, physical, chemical and biological properties of host soils and host plant characteristics influence their occurrence, taxonomic distribution and effectiveness. The interaction of these factors with vesicular-arbuscular mycorrhizae (VAM) is poorly understood except in a few cases. It is now very clear that VA mycorrhizal associations are ecologically significant factors that require more attention than previously accorded. This paper discusses the occurrence, distribution and significance of VAM in environmentally stressed soil conditions that limit plant growth such as drought, waterlogging and salinity. Key words: Mycorrhizas/Environmental factors/Waterlogging/Soil salinity/Growth development stages/ Inoculum
FUNGAL POPULATION, AFLATOXIN AND FREE FATTY ACID CONTENTS OF PEANUTS PACKED IN DIFFERENT BAG TYPES
Full text linkShelled peanuts of Gajah var. with initial moisture content of 7% were stored at 11 kg/bag in four bag types namely: jute bag, polypropylene bag, jute bag doubled with thin polyethylene (PE), and jute bag doubled with thick PE. Storage was done for six months under warehouse conditions with monitoring of relative humidity and temperature. Samples taken at the beginning of storage and every month thereafter were analyzed for moisture content, fungal population, aflatoxin and free fatty acid contents. Statistical analyses showed that moisture content, fungal population, and free fatty acid contents were significantly higher in jute and polypropylene bags than in PE-dou,bled jute bags. No significant differences were obtained in aflatoxin contents among bag types but at the end of six months storage, toxin level in jute bag exceeded the 30 ppb limit. Polypropylene had second highest toxin level at 23 ppb. The PE-doubled bags had 17 and 19 ppb total aflatoxins for thin and thick films, respectively. The results indicated that the immediate packaging of dried shelled peanuts at safe moisture level in plastic films with water vapor transmission rated of 1 g/m2/24 hr or lower is recommended. This packaging will delay critical increases in moisture content, fungal population, aflatoxin and free fatty acid contents of peanut kernels at ambient storage conditions. Keywords: Peanuts / bag types / fungal population / aflatoxin content / free fatty acid content
DIVERSITY OF Citrus spp. FROM PENAJAM PASER UTARA, EAST KALIMANTAN BASED ON MORPHOLOGICAL CHARACTERS
No full textARTICLE HIGLIGHTS- This research is the first study to provide data on the diversity of Citrus spp. from North Penajam Paser Regency (IKN) area, East Kalimantan for further development and breeding program. - This research offers new information on the distribution of Citrus spp. from the North Penajam Paser Regency (IKN) area, East Kalimantan. - This research provides information on the phenetic relationships among Citrus spp. from the North Penajam Paser Regency (IKN) area, East Kalimantan, and the morphological characteristics that play the most significant role in their clustering.
ABSTRACTCitrus spp. is local Indonesian fruit with high diversity and widely distributed around Indonesia country. Diversity and relationship data of Citrus spp. from Penajam Paser Utara-East Kalimantan has never been studied before. This study aimed to provide the diversity and relationship data of Citrus spp. from Penajam Paser Utara using morphological characteristics which served as the basic data for further development and breeding. The research was conducted through observation and sampling, followed by characterization and scoring of morphological data, and lastly the data analysis. The research succeeded in finding 35 accessions of Citrus spp. consisting of C. limon “Jeruk Lemon”, C. suhuensis, “Jeruk Siam”, C. aurantiifolia “Jeruk Nipis”, C. sinensis “Jeruk Manis”, C. maxima “Jeruk Bali”, C. microcarpa “Jeruk Kalamansi”, and Citrus sp. "Jeruk Sunkist" spread in sub-district Penajam, Sepaku, Babulu, and Waru. The dendrogram to clustering Citrus spp. in PPU was divided into two large clusters. Cluster A was grouped based on the character of tree habitus, cordate leaf apex, entire leaf margin, pink mesocarp color, and seed absence. Cluster B was grouped based on the character of the shrubs habitus, acute and rounded leaf apex, crenate leaf margin, white to orange mesocarp color, and numerous seeds in the fruit. This diversity made Citrus spp. from Penajam Paser Utara had high potential value for further development through a plant breeding program
Glomus mosseae AND Pseudomonas fluorescens AGAINST SOYBEAN MOSAIC VIRUS UNDER DRIP IRRIGATION SYSTEM
Full text linkARTICLE HIGLIGHTS- Glomus mosseae and Pseudomonas fluorescens enhance soybean resistance to SMV.- Ten-day drip irrigation stop at bloom stage boosts seed yield and weight.- Treatment reduces disease severity and increases P. fluorescens population.- Water-saving irrigation method improves soybean performance in dry seasons.- Combining G. mosseae and P. fluorescens increases soybean productivity.
ABSTRACTSoybeans [Glycine max (L.) Merr.] require much water, especially in the early stages of growth, flowering, and pod formation and filling. Drought stress on soybeans will increase with global climate change. The research aimed to evaluate the efficacy of Glomus mosseae and Pseudomonas fluorescens in inducing systemic resistance to control Soybean Mosaic Virus (SMV) and the performance of soybean plants with drip irrigation in the dry season. The drip irrigation was stopped for ten days at the beginning of bloom, full bloom, beginning pod, and regular drip irrigation. The application of G. mosseae inoculants used 100 g of sterile compost mixed with 30 spores. The liquid inoculum of P. fluorescens was applied on cotyledonary leaves using the watering method. The plants were inoculated with SMV 6 and 12 days after the P. fluorescens treatment. The symptoms of SMV were recorded two weeks after inoculation, and Indirect ELISA detected the virus. The results showed the combination of G. mosseae and P. fluorescens under drip irrigation stopped at the beginning of bloom for ten days on ELISA absorbance values and disease severity of 0.259 and 3.72 %, respectively. Moreover, this treatment showed the highest values for the 100-seed weight, seed yield, and fresh weight of leaves. The technique of giving water by stopping drip irrigation at the beginning of bloom for ten days will help save water and increase the P. fluorescens population optimally in Alfisols with a pH of between 4.5 and 5.1 with incredibly low fertility. The combination of G. mosseae and P. fluorescens population resulted in a significant increase in the number of G. mosseae’s spores by stopping drip irrigation at the beginning of bloom for ten days