Penyakit hawar daun bakteri yang disebabkan oleh Xanthomonas axonopodis pv. Allii dan Pantoe anan... more Penyakit hawar daun bakteri yang disebabkan oleh Xanthomonas axonopodis pv. Allii dan Pantoe ananatis merupakan penyakit penting pada tanaman bawang merah di sumatera dan provinsi penghasil bawang merah lainnya. Bakteri Xanthomonas axonopodis pv. Allii dan Pantoe ananatis mempunyai daerah sebaran yang luas. Penelitian ini bertujuan untuk mengetahui sebaran penyakit hawar daun bakteri pada tanaman bawang merah yang di sebabkan oleh Xanthomonas axonopodis pv. Allii dan Pantoe ananatis di Sumatera. Penelitian ini merupakan penelitian yang dilakukan dengan metode survey yaitu menghitung kejadian dan keparahan penyakit bawang merah yang ada di Sumatera. Berdasarkan penelitian yang dilakukan di lapangan diketahui bahwa adanya serangan penyakit hawar daun bakteri pada bawang merah yang di sebabkan oleh Xanthomonas axonopodis pv. Allii dan Pantoe ananatis dengan kejadian dan keparahan yang berbeda-beda. Kejadian tertinggi terdapat di provinsi Sumatera barat dengan kejadian penyakit 98 % dan keparahan penyakit sebesar 82,27% dan 79,47%
Biocontrol of Meloidogyne sp. on Tomato Plants by Selected Bacillus spp
IOP conference series, May 1, 2021
Meloidogyne spp., are recognize as the most economically important worldwide. It is difficult to ... more Meloidogyne spp., are recognize as the most economically important worldwide. It is difficult to control Meloidogyne spp., because they have wide range of hosts. Due to the high toxicity of chemical nematicides, it is necessary to develop new control strategies. Our previous research showed that some Bacillus spp. effective as biocontrol agents of plant pests and diseases. They have multifunction, such as plant growth promoter, phosphate dissolving bacteria, etc. The aim of this research was to obtain the selected Bacillus spp. to control Meloidogyne spp., to enhance growth and yield of tomato. The treatments were 8 strains of Bacillus spp., Carbofuran, Meloidogyne spp. inoculated tomato and control. The Bacillus spp. have inoculated as seed treatment and seedling treatment before transplanting. The Meloidogyne spp. have inoculated on 4 weeks tomato plants. The parameters were disease development, multiplication of Meloidogyne spp., growth and yield of tomato. The results showed that Bacillus spp. reduced the number of galls, egg masses, eggs per egg mass and nematode per 300 g soil compared to the inoculated control, but the nematicide treatments was more effective to control Meloidogyne spp. Conversely, three strains of Bacillus spp. showed to enhance the growth and yield of tomato than Carbofuran.
Penapisan Isolat Rizobakteria dari Perakaran Tanaman Kentang Yang Sehat Untuk Pengendalian Penyakit Layu Bakteri (Ralstonia solanacearum) di Kabupaten Solok
Biochemical Characterizations of Selected Indigenous Endophytic Bacteria Potential as Growth Promoters and Biocontrol Agents on Tomato
IOP conference series, May 1, 2021
Nine indigenous endophytic bacteria strains showing the best ability to promote growth and contro... more Nine indigenous endophytic bacteria strains showing the best ability to promote growth and control tomato pathogens had been screened in our previous research. The strains’ biochemical properties, such as nutrition and other traits, must be characterized to design the best formulations for the strains’ biochemical properties. This study aimed to describe the biochemical characteristics of the selected indigenous endophytic bacteria. The variables observed were utilization of carbon sources (glucose, fructose, sucrose, lactose, glycerol, and olive oil), nitrogen sources (peptone, yeast extract, urea, NH4Cl, NH4SO4, and NH4NO3), and citrate, hydrolytic activities (urease, triple sugar iron, starch hydrolysis, gelatin hydrolysis, chitinase, cellulase, protease, lipase, and catalase), oxidative/fermentative assay, salt tolerance, and growth ability at 4° and 44°C. This study showed that all the endophytic bacteria strains characterized had various biochemical characteristics. All strains showed the different ability to utilize nitrogen and carbon source. Some strains survived to grow at 4°C except Bacillus cereus AGBE 1.2 TL. All strains tolerate growth in 4% NaCl concentrations, while some strains can tolerate up to 6%. This result can be used for further studies to develop the most suitable formulations for each strain to get the best results of the growth-promoting and biocontrol activities of the indigenous endophytic bacteria strains.
Nagari Sungai Talang is one of the villages in Payakumbuh District, Lima Puluh Kota Regency which... more Nagari Sungai Talang is one of the villages in Payakumbuh District, Lima Puluh Kota Regency which seeks to cultivate ginger plants. Ginger (Zingiber officinale Rosc.) is a spice plant native to Indonesia. Ginger has long been cultivated and consumed by the community. The part of the ginger plant that is consumed is the rhizome. One of the problems in ginger cultivation in Indonesia is the low productivity and quality of ginger. Ginger seeds in the form of rhizomes must be processed and stored as well as possible so that their quality can be maintained longer by inhibiting the rate of seedling decline. The purpose of this service activity is to invite farmers, especially the Innovation farmer group in order to sort ginger seeds with government assistance (selection of good and healthy ginger seeds) so that the production of ginger plants can increase even better than the previous cultivation. The method of implementing this service is Community Education. Community education in this activity by carrying out socialization and counseling aimed at increasing knowledge and understanding of the community, especially ginger farmers about good and healthy ginger to be used as seeds for the implementation of further cultivation in the field. The results obtained from this empowerment activity are that the farmer group understands the type of rhizome that is chosen to be used as the next seed. The selection of the type of rhizome can be seen from the number of good buds, uniform shoot height, age of rhizome, and appearance of ginger rhizome.
Xanthomonas axonopodis pv. alii (Xaa), which causes bacterial leaf blight on shallots, can cause ... more Xanthomonas axonopodis pv. alii (Xaa), which causes bacterial leaf blight on shallots, can cause yield losses both in quantity and quality to reach 100% if the environmental conditions are suitable for its development. Indigenous Rhizobacteria, Bacillus spp. reported to be effective for controlling plant diseases and can increase plant growth and yield. The study aimed to obtain Bacillus spp. isolates capable of controlling bacterial leaf blight and increasing the growth and yield of shallots. The study consisted of 3 stages. The first is the isolation of Bacillus spp. from soil and shallot roots in production centers and endemic areas of bacterial leaf blight in Solok and Agam districts, West Sumatra. The second is control of bacterial leaf blight with Bacillus spp. At this stage, research was experimental in the experimental garden of the Agriculture Faculty, Universitas Andalas, consisting of 43 treatments and three replications. The treatments consisted of 40 isolates of Bacillus spp., Streptomycin, control + (without Xaa and Bacillus spp.), and control-(Xaa inoculated, without Bacillus spp.). Bacillus spp. introduced to shallot seeds. Xaa is inoculated by wounding the surface of the leek using a sterile needle, then the Xaa suspension is applied to the injured area, and the plant is covered with clear plastic. The third is the identification and characterization of selected Bacillus spp. to control bacterial leaf blight and increase shallot yield. The results showed that nine isolates of Bacillus spp. increased the resistance of shallots to bacterial leaf blight from susceptible to resistant, and five isolates were also able to increase the yield of shallots by 388-433% compared to controls. Based on the molecular identification of the five isolates, MRTDE2.6 was B. subtilis BSn5; MRSNRZ1.2 is B. mycoides strain ATCC 6462; MRBPRZ1.1 is B. thuringiensis strain IAM 12077; MRRZLL2.2 is B. mycoides strain ATCC 6462, and MRRDE3.4 is B. weihenstephanensis strain ATCC 6457. Biochemical characteristics of 5 species of Bacillus spp. selected were three species produced siderophore, none made HCN, three species produced salicylic acid, two species had protease enzymes, three species produced ammonia, all produced biosurfactant, all were hemolysin negative, and all species produced IAA.
Biological control of Sclerotium rolfsii on tomato seedlings using Bacillus spp. consortium
IOP conference series, May 1, 2021
The Sclerotium rolfsii which widely distributed soil-borne plant pathogen, causes many economical... more The Sclerotium rolfsii which widely distributed soil-borne plant pathogen, causes many economically important crops severely reduce their yield at worldwide extend, including tomato and are very difficult to control due to its sclerotia. The beneficial plant-microbe interactions play crucial roles in protection against large number of plant pathogens causing disease. Our previous research had screened 9 Bacillus spp. strains which had ability to control R. syzigii subsp. indonesiensis and promote growth and yield of solanaceous plants. Those strains were Bacillus cereus AGBE 1.2 TL, Bacillus toyonensis AGB E 2.1 TL, Bacillus cereus SLB E 1.1 SN, Bacillus cereus SLB E 1.1 AP, Bacillus pseudomycoides SLB E 3.1 AP, Bacillus cereus SLB E 1.1 BB, Bacillus cereus SLB E 2.1 BB, Bacillus thuringiensis SLB E 2.3 BB, and Bacillus cereus SLB E 3.1 BB. Our current study objective was to develop the best consortium to control S. rolfsii and promote growth of S. rolfsii seedlings. The research designed in experimental methods and was arranged in a completely randomized design with 7 treatments and triplications. The methods done were compatibility assay of the Bacillus strains, development of consortium based from the compatibility, and consortium assay to control S. rolfsii and promote growth of tomato seedlings. The result showed, out of the 6 compatible consortiums, consortium A4 consists of Bacillus strain AGBE 1.2 TL, SLBE 3.1 AP, SLBE 2.1 BB and SLBE 3.1 BB were shown to be the best to control S. rolfsii on tomato seedlings with 85.00% of the seedlings were shown no symptoms. The consortium also had the best ability to promote growth of tomato seedlings up to 25.00% compared with control.
Egyptian Journal of Biological Pest Control, Mar 22, 2023
Background Anthracnose disease caused by Colletotrichum capsici is a major disease in chili plant... more Background Anthracnose disease caused by Colletotrichum capsici is a major disease in chili plants that is difficult to control. Actinobacteria have potential biological control agents for C. capsici because of their antifungal properties and dominant presence in soil. The study aimed to obtain actinobacteria isolates that have the potential to control anthracnose in planta and increase the growth and production of chili plants. The study consisted of three stages: isolation, selection, and characterization of the best actinobacteria isolates. A total of 20 isolates of indigenous actinobacteria were isolated, and 16 isolates were successfully selected based on the results of the biosafety test. Results The in planta test showed that eight isolates could control anthracnose with 100% effectiveness. Of the eight isolates, as many as five players increased the production of chili plants by 169.51-218.53 g. Actinobacterial isolates that have the potential to control anthracnose disease in planta and increase the growth and production of chili plants are ARAI 3221, ARAC 3221, ARAC 2211, ARAC 3321, and ARTI 1312. These isolates produced indole acetic acid (IAA) with concentrations of 25.82-88.87 ppm, and four isolates were able to dissolve phosphate. Five isolates produced chitinase enzyme with the chitinolytic index of 0.32-1.78. Conclusion The introduction of actinobacteria in chili plants was also proven to extend the incubation period, reduce the incidence of disease, and reduce the severity of anthracnose disease compared to negative controls and mancozeb. Actinobacteria can suppress pathogenic microorganisms that can inhibit plant growth. Actinobacteria have the potential to increase the growth and production of chili plants. The results of 16S rRNA sequences showed that the five potential isolates were identified as Streptomyces cellulose, S. fradiae, S. olivaceus, S. pseudogriseolus, and S. griseoflavus.
Growth response and yield of potato plant with applications of rhizobacteria and mycorrhizal
IOP conference series, Apr 1, 2023
The potato plant is a primary horticultural crop that can be used in place of food diversificatio... more The potato plant is a primary horticultural crop that can be used in place of food diversification. The study’s goal is to find the best interaction between rhizobacteria and mycorrhizal on the growth and yield of the potato plant. This study was conducted at the Andalas University, Padang Faculty of Agriculture’s Microbiology and Plant Physiology Laboratories and experimental garden Institute Assessment and Agricultural Technology in Sukarami Solok, from July to December 2018. A 2-factor factorial design with replication and a fully randomized design was employed CRD. The type of rhizobacteria is the first factor: no Rhizobacteria, RZ.1.L2.3, RZ.3.L2.1, RZ.3.L2.2, RZ.1.L2.3, and the second factor is Multispora, Acaulospora, Glomus SP2, and Sclerocystis. Each treatment was replicated three times, consisting of 60 experimental units. The data were analyzed using the STAR application whit a 5% F test, and if significantly different, followed by a 5% HSD test. The outcome demonstrated an interaction between rhizobacteria and mycorrhizal on the fresh weight of the tuber.
Exploration of the indigenous rhizosphere fungi as corncob waste decomposers and its potential as biological agent Fusarium graminearum and increase corn growth
IOP conference series, Apr 1, 2023
Corncob waste can be used as compost; corncob compost that microbial decomposers have composted p... more Corncob waste can be used as compost; corncob compost that microbial decomposers have composted positively affects soil and plants. The objectives of this study are 1). It was obtaining the type of fungi from the corn rhizosphere that acts as a decomposer of corncob waste and 2) knowing the potential of corncob waste compost in suppressing F. graminearum, which causes stem rot on corn and increasing plant growth. The designs used for the two steps of the study were: Randomized Block Designs with ten treatments and four replication. The first step is using the rhizosphere fungi isolates for composting corncob waste. The second step is testing corncob composted by ten different types of rhizosphere fungi to suppress corn stem rot caused by F. graminearum. Parameters observed in the first step were: the number of conidia and the number of propagules of rhizosphere fungi in corncobs compost. The third step was: Incubation period, disease incidence, disease severity, number of dead plants, and plant growth. The result of the research indicated that the corn rhizosphere obtained 15 isolates of fungi that varied the color, shape of the colony, and growth rate. The highest number of propagules was found in compost decomposed by rhizosphere fungi RF4, while the number of conidia classified as high was found in RF4, Rf, and RF6 compost. All corncob compost decomposed by rhizosphere fungi was able to suppress stem rot disease caused by F. graminearum.
Endophyte bacteria colonize plant roots and exert a beneficial effect on plant growth are well kn... more Endophyte bacteria colonize plant roots and exert a beneficial effect on plant growth are well known for their potential to reduce plant pathogen populations in the soil, thereby suppressing diseases. Elucidation of signaling pathways controlling disease resistance is a major objective in research on plant-pathogen interactions. It has been suggested that jasmonic acid (JA) could be an integral part of a general signal transduction system regulating inducible defense genes in plants. Recent studies had shown that Endophyte bacteria could elicited induce systemic resistance (ISR) of plants by jasmonic acid pathway. This research purposed to study the involvement of JA in ISR of tomato plants against Ralstonia syzigiisubsp. Indonesiensis by indigenous endophyte bacteria. This research assayed the JA contained in the leaves and roots of tomato plants that treated with indigenous endophyte bacteria (seed and seedlings treatment) and inoculated with R. syzigiisub sp. Indonesiensis with Gas Chromatography-Mass Spectrophotometry (GC-MS) in interval between 0 to 30 days after pathogen innoculation. Results shown that all selected indigenous endophyte bacteria can suppress R. syzigiisub sp. Indonesiensis attack and increase JA contained in leaves and roots of tomato significantly until 12 days after pathogen innoculations. Strain Bacillus cereus EPL1.1.3 and Serratianematodiphila TLE1.1 respectively had the highest JA activivity both in roots and leaves of tomato. This indicated that one of the selected indigenous endophyte bacteria abilities to suppress pathogens attack mechanism related to JA pathway.
IOP Conference Series: Earth and Environmental Science, 2019
Logistic regression has become a popular method for handling predictive modeling when the respons... more Logistic regression has become a popular method for handling predictive modeling when the response variable has a categorical scale. The difference in category proportion in response variable could influence the prediction accuracy. This research applied the model averaging approach for logistic regression in purpose to improve the prediction accuracy in different proportion of each category. Model averaging has the idea to combine some model candidates based on the specified weight to be the final model. The model candidate in model averaging generated based on all possibilities variable selection in the model. AIC weight is chosen to apply in the combination of all possible model candidates. It is illustrated with an application to data from a classification of Autistic Spectrum Disorder data. The result of this case indicated that the logistic model averaging had better performances.
The Ability of Chitinolytic Bacteria to Control Colletotrichum capsici in Chili Plants
IOP Conference Series: Earth and Environmental Science
Anthracnose disease caused by Colletotrichum capsici is one of the important diseases in chili pl... more Anthracnose disease caused by Colletotrichum capsici is one of the important diseases in chili plants that can reduce yields up to 50-100%. Chitinolytic bacteria Bacillus thuringiensis AGBE 3.3.BB, B. cereus SLBE1.1. SN and B. toyonensis AGBE1.2.TL were antagonistic to C. capsici. This study aimed to determine the potential of chitinolytic bacteria in controlling C. capsici in chili plants. Three bacterial isolates were formulated using bran as a carrier medium. The research was divided into four stages: antagonist test, viability test, ability test of biological agents to control C. capsici and plant growth. This study showed that the severity of anthracnose in the bacterial formulation of B. thuringiensis strain AGBE 3.3 BB was lower, which was 64.3% compared to the control. Tests showed that the formulation of B. cereus SLBE1.1. SN, formulation B. toyonensis strain AGBE1.2TL, formulation B. thuringiensis strain AGBE 3.3 BB, and the consortium formulation could inhibit C. capsici ...
Bacterial wilt caused by Ralstonia solanacearum is the important dangerous diseases in chili. Unt... more Bacterial wilt caused by Ralstonia solanacearum is the important dangerous diseases in chili. Until now this disease has been difficult to control; while the bacteria attack the xylem vessel they cannot be reached by any bactericide. Biocontrol is potential for controlling this disease. One group of important biocontrol agents is the plant growth promoting rhizobacteria (PGPR). Based on in planta screening method, we have found 13 indigenous rhizobacterial strains from healthy chili’s rhizosphere, which have the ability to control bacterial wilt and to increase growth and yield of chili. This research is aimed at characterizing the direct mechanisms of selected indigenous rhizobacterial strains as biocontrol agents of R. solanacearum in vitro. The physiological characters of indigenous rhizobacterial strains as biocontrol agents had been observed, including production of antibiotic, siderophore, HCN, haemolysine, protease, and biosurfactan. For root colonization rifampicin mutants o...
Antagonistic effects of actinomycetes towards plant pathogen Phellinus noxius
2012 IEEE Colloquium on Humanities, Science and Engineering (CHUSER), 2012
Several strains of actinomycetes have been found to protect plant from plant pathogens because th... more Several strains of actinomycetes have been found to protect plant from plant pathogens because the capacity to produce a wide variety of antibiotics, extracellular enzymes and also show their antagonistic effects towards plant pathogen. Actinomycetes play an important role in degradation of chitin which is a component of cell wall of fungi. Application of selected Actinomycetes as biocontrol can decrease the environmental pollution and an alternative to fungicides. Brown root disease caused by Phellinus noxius was observed in teak plantations of Sabak Bernam in Selangor, Kuala Kangsar in Perak, Sik in Kedah and Lendu in Malacca. It will affect the plantations industry if no measures are taken to control or manage it. This pathogen grew faster on the Potato Dextrose Agar and also on selective media such as Malt Yeast Extract Agar. Analysis of the 16S rDNA begins by extracting the Actinomycetes DNA and amplifying the gene coding for 16S rDNA using the polymerase chain reaction. The purified DNA fragments are directly sequenced and identification of the actinomycetes was done using phylogenetic analysis procedures. However, analysis of 16S rDNA generally allows us to identify the organisms up to the genus level only. Three selected actinomycetes isolated from the soil were found to control this plant pathogen. These actinomycetes controlled the plant pathogen by hyperparasiting it and colonizing its hyphae. The chitinase production of actinomycetes was determined by inoculating culture strains on chitin-yeast-extract agar and its chitinolytic activity was determined by formation of clear zones around the actinomycetes colonies.
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