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Biocontrol Ability of Puccinia abrupta var. partheniicola on Different Growth Stages of Parthenium Weed (Parthenium hysterophorus L.) Полный текст
2010
FAUZI, MOHAMAD TAUFIK
A research was conducted to investigate the biological control ability of Puccinia abrupta var. partheniicola infected to parthenium weed (Parthenium hysterophorus L.) at different stages of growth in a glasshouse. The study also investigated the combined effect of the infection and the competitor plant, i.e. buffel grass (Cenchrus ciliaris L.), a pasture species usually found in the weed habitat in Central Queensland. The 2 x 3 factorial experiment was arranged in a completely randomized design with six replicates in each treatment. The parthenium weeds were planted with or without buffel grass. The plants were inoculated with P. abrupta var. partheniicola urediniospores either at the rosette, flowering or mature growth stage of development. As controls, an additional six non inoculated plants with and without buffel grass were planted. The results showed that P. abrupta var. partheniicola affected more on the younger plants than on the older ones. Its infection decreased the plant height. A higher reduction in plant above ground biomass was recorded because of the rust when the plants were inoculated at the rosette growth stage of development in the presence of competition. The impact of the rust was greatest on the ability of parthenium to produce seeds. Key words: Puccinia abrupta var. partheniicola, biological control, parthenium weed
Показать больше [+] Меньше [-]Molecular Phylogenetic Classification of Streptomycetes Isolated from the Rhizosphere of Tropical Legume (Paraserianthes falcataria) (L.) Nielsen Полный текст
2010
SEMBIRING, LANGKAH
Intrageneric diversity of 556 streptomycetes isolated from the rhizosphere of tropical legume was determined by using molecular taxonomic method based on 16S rDNA. A total of 46 isolates were taken to represent 37 colour groups of the isolates. 16S rDNA were amplified and subsequently sequenced and the sequences data were aligned with streptomycete sequences retrieved from the ribosomal data base project (RDP) data. Phylogenetic trees were generated by using the PHYLIP software package and the matrix of nucleotide similarity and nucleotide difference were generated by using PHYDIT software. The results confirmed and extended the value of 16S rDNA sequencing in streptomycete systematic. The 16S rDNA sequence data showed that most of the tested colour group representatives formed new centers of taxonomic variation within the genus Streptomyces. The generic assignment of these organisms was underpinned by 16S rDNA sequence data which also suggested that most of the strains represented new centers of taxonomic variation. The taxonomic data indicate that diverse populations of streptomycetes are associated with the roots of tropical legume (P. falcataria). Therefore, the combination of selective isolation and molecular taxonomic procedures used in this study provide a powerful way of uncovering new centers of taxonomic variation within the genus Streptomyces. Key words: molecular phylogenetic, classification, streptomycetes, rhizosphere, Paraserianthes falcatharia
Показать больше [+] Меньше [-]Fungal Succession and Decomposition of Acacia mangium Leaf Litters in Health and Ganoderma Attacked Standings Полный текст
2010
SAMINGAN, SAMINGAN | SUDIRMAN, LISDAR IDWAN
Leaf litters of Acacia mangium play an important functional role in ecosystem, producing sources of nutrients and giving diversity of microorganisms. Understanding the variation in fungal populations in A. mangium forest is important due to the roles of fungi in regulating populations of other organisms and ecosystem processes. For these purposes, the tests were conducted under two years old of health standing (2S) and Ganoderma attacked standing (2G) using litterbag method. Litter weight loss and lignin, cellulose, C, N contents were measured each month during eight months of decomposition, as well as fungal community involved was observed. Litter weight loss and lignin, cellulose, C, N contents were measured each month during eight months of decomposition, as well as fungal community involved was observed. After eight months of decomposition, litter weight losses were low up to 34.61% (k = 0.7/year) in 2S and 30.64% (k = 0.51/ year) in 2G, as well as lignin weight losses were low up to 20.05% in 2S and 13.87% in 2G. However, cellulose weight losses were 16.34% in 2S and 14.71% in 2G. In both standings, the numbers of fungal species were 21 and 20 respectively, while the total of fungal populations tends to increase after one month of decomposition and tend to decrease in the last three months. In the first and second months of decomposition fungal species were dominated by genera of Penicillium and Aspergillus and the last three months by Trichoderma, Phialophora, and Pythium. Key words: fungal succession, decomposition, leaf litters, A. mangium
Показать больше [+] Меньше [-]Purification and Characterization of ?-1,3-Glucanase from the Antagonistic Fungus Trichoderma reesei Полный текст
2010
BUDIARTI, SRI WAHYUNI | WIDYASTUTI, SITI MUSLIMAH | MARGINO, SEBASTIAN
Trichoderma enzymes that inhibit fungal cell walls have been suggested to play an important role in mycoparasitic action against fungal root rot pathogen Ganoderma philippii. This experiment was aimed to purify and characterize the ?-1,3-glucanase of T. reesei. Extracellular ?-1,3-glucanase was produced by growing mycoparasite T. reesei isolate T13 in colloidal chitin and sucrose as carbon sources. The enzyme was then purified to its homogeneity by precipitation with ammonium sulfate, followed by gel filtration chromatography and chromatofocusing. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) 12% was used to confirm the purity of enzyme at each stage of preparation and to characterize purified protein. The results showed that T. reesei produced at least three extracellular ?-1,3-glucanases. Estimation of molecular weight based on SDS-PAGE 12% have three isoform of ?-1,3-glucanase were 90 kDa for ?-1,3-glucanase-I, 75 kDa for ?-1,3-glucanase-II, and 64 kDa for ?-1,3-glucanase-III. Their optimum pH and temperature were 5 and 50 oC, respectively. Key words: ?-1,3-glucanase, Trichoderma reesei, Ganoderma philippii
Показать больше [+] Меньше [-]Study of morphological and physiological characteristics of the tolerant and sensitive mungbean genotypes to shading was carried out in the Station Research of the Indonesian Legume and Tuber Crops Research Institute (ILETRI) from September to December 2004. Nine tolerant genotypes (MMC 87 D-KP-2, MLG 369, MLG 310, MLG 424, MLG 336, MLG 428, MLG 237, MLG 429, and VC2768B) and three sensitive genotypes to shading (Nuri, MLG 460, and MLG 330) were tested in two shading levels, that were without shading and shading of 52%. The randomized complete block design with three replications analysis. The results showed that leaf characters of shading tolerant and sensitive genotypes were different. The shading tolerant mungbean genotypes had good response to light stress so that the growth and development of the leaves were better than that of sensitive genotypes. The shading tolerant mungbean genotypes had bigger and thicker leaves than that of sensitive genotypes. The shading treatments caused reducing rate of PAR absorption, transpiration, photosynthesis, and CO2 stomata conductance. The reduction of all parameters in tolerant genotype was smaller than that of sensitive genotype. The specific leaf area at four weeks after planting could be used as shading tolerant indicator of mungbeans. Key words: mungbean, characteristics, morphology, physiology, leaves, tolerant, sensitive, shading Полный текст
2010
SUNDARI, TITIK
Study of morphological and physiological characteristics of the tolerant and sensitive mungbean genotypes to shading was carried out in the Station Research of the Indonesian Legume and Tuber Crops Research Institute (ILETRI) from September to December 2004. Nine tolerant genotypes (MMC 87 D-KP-2, MLG 369, MLG 310, MLG 424, MLG 336, MLG 428, MLG 237, MLG 429, and VC2768B) and three sensitive genotypes to shading (Nuri, MLG 460, and MLG 330) were tested in two shading levels, that were without shading and shading of 52%. The randomized complete block design with three replications analysis. The results showed that leaf characters of shading tolerant and sensitive genotypes were different. The shading tolerant mungbean genotypes had good response to light stress so that the growth and development of the leaves were better than that of sensitive genotypes. The shading tolerant mungbean genotypes had bigger and thicker leaves than that of sensitive genotypes. The shading treatments caused reducing rate of PAR absorption, transpiration, photosynthesis, and CO2 stomata conductance. The reduction of all parameters in tolerant genotype was smaller than that of sensitive genotype. The specific leaf area at four weeks after planting could be used as shading tolerant indicator of mungbeans. Key words: mungbean, characteristics, morphology, physiology, leaves, tolerant, sensitive, shading
Показать больше [+] Меньше [-]Eriborus argenteopilosus is the most important parasitoid attacking cabbage pest Crocidolomia pavonana in Indonesia. Previous studies proved that parasitoid encapsulation was found to be an important factor limiting the effectiveness of the parasitoid in controlling pest population in the field. Since 1998, we have conducted series studies to investigate encapsulation mechanism developed by hosts against parasitoid, responses of parasitoid toward encapsulation ability and to determine factors that may help parasitoid avoid encapsulation. Parasitoid responses were examined on two different hosts C. pavonana and Spodoptera litura. Our findings showed that parasitization level was found to be high both on C. pavonana and S. litura. Encapsulation occurred to be high in all larva stages of C. pavonana, in contrast encapsulation was recorded very low in all larvae stages of S. litura. We recorded that encapsulation in the larval body of C. pavonana was completed in 72 hours and mostly occurred in higher larval stage. Melanization was only recorded in encapsulated parasitoid inside larva body of C. pavonana, not in S. litura. We recorded that encapsulation increased blood cell number of both larvae C. pavonana and S. litura. Encapsulation may affect development of immature parasitoid. Weight of S. litura’s pupae containing encapsulated parasitoid was found to be lower in S. litura, but not in C. pavonana. Our investigation also proved that superparasitism may help parasitoid avoid encapsulation. Key words: parasitoid, encapsulation, melanization, blood cell number, superparasitism Полный текст
2010
BUCHORI, DAMAYANTI | SAHARI, BANDUNG | RATNA, ENDANG SRI
Eriborus argenteopilosus is the most important parasitoid attacking cabbage pest Crocidolomia pavonana in Indonesia. Previous studies proved that parasitoid encapsulation was found to be an important factor limiting the effectiveness of the parasitoid in controlling pest population in the field. Since 1998, we have conducted series studies to investigate encapsulation mechanism developed by hosts against parasitoid, responses of parasitoid toward encapsulation ability and to determine factors that may help parasitoid avoid encapsulation. Parasitoid responses were examined on two different hosts C. pavonana and Spodoptera litura. Our findings showed that parasitization level was found to be high both on C. pavonana and S. litura. Encapsulation occurred to be high in all larva stages of C. pavonana, in contrast encapsulation was recorded very low in all larvae stages of S. litura. We recorded that encapsulation in the larval body of C. pavonana was completed in 72 hours and mostly occurred in higher larval stage. Melanization was only recorded in encapsulated parasitoid inside larva body of C. pavonana, not in S. litura. We recorded that encapsulation increased blood cell number of both larvae C. pavonana and S. litura. Encapsulation may affect development of immature parasitoid. Weight of S. litura’s pupae containing encapsulated parasitoid was found to be lower in S. litura, but not in C. pavonana. Our investigation also proved that superparasitism may help parasitoid avoid encapsulation. Key words: parasitoid, encapsulation, melanization, blood cell number, superparasitism
Показать больше [+] Меньше [-]Two random amplified polymorphic DNA (RAPD) markers linked to CMV-B2 resistance gene (Creb-2) in melon cultivar Yamatouri were cloned and sequenced to design sequence characterized amplified region (SCAR) markers for detection of CMV-B2 resistance gene (Creb-2) in melon. SCOPE14 derived from OPE-14 yielded a single DNA band at 541 bp, while SCAPB05 derived from APB-05, yielded a single DNA band at 1,046 bp, respectively. Segregation of SCOPE14 and SCAPB05 markers in bulk of F2 plants demonstrated that they were co-segregated with RAPD markers from which the SCAR markers were originated. Furthermore, results of SCAR analysis in diverse melons showed SCAPB05 primers obtained a single 1,046 bp linked to Creb-2 in resistant cultivars Sanuki-shirouri and Kohimeuri. However, SCOPE14 failed to detect Creb-2 in diverse melons. Results of this study revealed that SCAR analysis not only confirmed melons that had been clearly scored for resistance to CMV-B2 by RAPD markers, but also clarified the ambiguous resistance results obtained by the RAPD markers. Key words: Cucumis melo L., Creb-2, RAPD, SCAR Полный текст
2010
DARYONO, BUDI SETIADI | WAKUI, KENJI | NATSUAKI, KEIKO T.
Two random amplified polymorphic DNA (RAPD) markers linked to CMV-B2 resistance gene (Creb-2) in melon cultivar Yamatouri were cloned and sequenced to design sequence characterized amplified region (SCAR) markers for detection of CMV-B2 resistance gene (Creb-2) in melon. SCOPE14 derived from OPE-14 yielded a single DNA band at 541 bp, while SCAPB05 derived from APB-05, yielded a single DNA band at 1,046 bp, respectively. Segregation of SCOPE14 and SCAPB05 markers in bulk of F2 plants demonstrated that they were co-segregated with RAPD markers from which the SCAR markers were originated. Furthermore, results of SCAR analysis in diverse melons showed SCAPB05 primers obtained a single 1,046 bp linked to Creb-2 in resistant cultivars Sanuki-shirouri and Kohimeuri. However, SCOPE14 failed to detect Creb-2 in diverse melons. Results of this study revealed that SCAR analysis not only confirmed melons that had been clearly scored for resistance to CMV-B2 by RAPD markers, but also clarified the ambiguous resistance results obtained by the RAPD markers. Key words: Cucumis melo L., Creb-2, RAPD, SCAR
Показать больше [+] Меньше [-]Intracellular Ca2+ Regulation in Calcium Sensitive Phenotype of Saccharomyces cerevisiae Полный текст
2010
HERMANSYAH, .
Intracellular cytosolic Ca2+ concentration accumulation plays an essential information in Saccharomyces cerevisiae i.e. to explain cellular mechanism of Ca2+ sensitive phenotype. Disruption both S. cerevisiae PPase PTP2 and MSG5 genes showed an inhibited growth in the presence of Ca2+. On the other hand, by using Luminocounter with apoaequorin system, a method based upon luminescent photoprotein aequorin, intracellular Ca2+ concentration was accumulated as a consequence of calcium sensitive phenotype of S. cerevisiae. This fact indicated that PPase ptp2D and msg5D were involved in intracellular Ca2+ transport in addition their already known pathways i.e Mitogen Activated Protein Kinase cell wall integrity pathway, high osmolarity glycerol (HOG) pathway, and pheromone response FUS3 pathway.
Показать больше [+] Меньше [-]Differential Regulation of the Nodulation Zone by Silver Ions, L--(2-Amino-Ethoxyvinyl)-Glycine, and the skl Mutation in Medicago truncatula Полный текст
2010
Prayitno, Joko | Mathesius, Ulrike
Nodule formation in Rhizobium-legume symbiosis is negatively regulated by ethylene. Ethylene inhibitors such as L-a-(2-amino-ethoxyvinyl)-glycine (AVG) and silver ions (Ag+), the ethylene-insensitive sickle mutant, and transgenic plants were used to study ethylene-mediated responses in nodulation. The mode of action of ethylene inhibitors AVG and Ag+, and the skl mutation occur at different steps in ethylene biosynthesis and perception. Their effects on root growth and nodulation phenotypes, in particular nodule distribution along the primary root, were compared in this study. Ag+ and AVG treatments showed similar root growth responses to skl mutant. However, nodule distribution in the hypernodulating skl mutant is different from that of wild-type plants grown on either AVG or Ag+. AVG increased nodule numbers and widened the nodulation zone, while the skl mutant had an increased number of nodules within the susceptible zone of nodulation. Ag+ reduced nodule numbers, restricted the nodulation zone, and restored the nodulation phenotype of skl to that of the wild type.
Показать больше [+] Меньше [-]Diversity and Effectiveness of Insect Pollinators of Jatropha curcas L. (Euphorbiaceae) Полный текст
2010
Rianti, Puji | Suryobroto, Bambang | Atmowidi, Tri
Seed of Jatropha curcas (Euphorbiaceae) is currently established as the source for biofuel Therefore, it is important to understand the diversity insects that pollinated J. curcas inflorescence yellow flowers. We also aimed to study the pollination effects on fruit set on J. curcas. Scan sampling method were carried out to explore the insect pollinators diversity from 07.00 up to 17.00 h in every 15 minutes. Visiting frequency of pollinators insects were observed by using focal sampling. Those information together with flowering periods, flower nectar volumes, and environmental factors were used as the basic data to determine the effectiveness of insect pollination both in covered and uncovered of seed set plants. Results showed that nine species of insect pollinators were from three order (Hymenoptera, Lepidotera, and Diptera) pollinated J. curcas. Four species of Hymenoptera i.e. Prenolepis, Apis dorsata, Xylocopa confusa, and Apis cerana showed the highest abundances. The highest abundance and species richness of pollinators occurred at 08.00-10.15 and 15.00-17.15 h. Bees of X. confusa, A. cerana, and A. dorsata of Apidae are effective as insect pollinators in J. curcas plantations, due to high visited frequencies. The insect pollinators also increased fruits and seeds set of J. curcas in the uncovered experiment plants. Thereby, enhancement the three pollinator insects as part of crop management have to be considered by farmers.
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