Jurnal Fitopatologi Indonesia
Not a member yet
412 research outputs found
Sort by
Ekspresi Rekombinan Gen Protein Selubung Pepper vein yellows virus
Pepper vein yellows virus (PeVYV) isolate from Bali have been identified from pepper plants with chlorosis symptoms. Specific antiserum of PeVYV had not available yet commercially. One of the advance techniques in providing a source of abundant antigen for antiserum production is through molecular approach by overexpressed the coat protein gene in suitable bacterial expression system. PeVYV coat protein gene of ~650 bp in size was amplified using specific primers, then was cloned into pQE30 expression vector and was over expressed in E. coli strain M15 [pREP4]. SDS-PAGE analysis showed that the recombinant coat protein gene of PeVYV was successfully expressed protein band with size of ~25 kDa at 6 hours after induction by 0.5 mM IPTG on 37 °C
Keragaman Cendawan Rizosfer dan Potensinya sebagai Agens Antagonis Fusarium oxysporum Penyebab Penyakit Layu Tanaman Krisan
Plant rhizosphere is rich of microbes, one of these is a group of fungi. This research aimed to obtain fungi isolates from rhizosphere of healthy Chrysanthemum, followed by evaluation of their potential as biocontrol agents of Fusarium oxysporum. Isolation of fungi rhizosphere was based-on serial dilution method. As many as 6 isolates of rhizosphere fungi was succesfully isolated with diverse characters. Pathogenicity test showed that 6 isolates were not pathogenic because it did not cause wilt symptoms on Chrysanthemum. The selected isolates were subjected to in vitro assay for their potential as biocontrol agents, 4 isolates had antagonist ability (46.42–51.61%) and antibiosis activity against F. oxysporum. Fungi isolates having the potential as biocontrol agents was identified as Trichoderma sp. (2 isolates), Penicillium sp., and Paecillomyces sp
Eksplorasi Fusarium Nonpatogen untuk Pengendalian Penyakit Busuk Pangkal pada Bawang Merah
Fusarium oxysporum f. sp. cepae causing basal rot disease is one of an important constrains in shallot productions. Result from several studies showed that non-pathogenic F. oxysporum was very potential to control fusarium basal rot in shallot. This study was conducted to explore non-pathogenic isolates of F. oxysporum from shallot fields which might be effective for controlling basal rot disease. Eighteen out of 21 isolates did not cause any disease symptom, they even promoted shallot growth when inoculated onto bulbs. Three out of 18 selected isolates, i.e. P13a, T14a, and P21a were the most effective isolates in controlling the disease in two consecutive experiments with level of efficacy ranges from 61.2% to 83.3%. This level of efficacy was higher than those of fungicide (benomyl) treatment
Deteksi Bakteri Penyebab CVPD pada Jeruk Menggunakan DNA Asal Tulang Daun
A method for identification of the causal bacteria of citrus vein phloem degeneration (CVPD) based on polymerase chain reaction (PCR) technique using template DNA extracted from leaf midrib of citrus has been implemented routinely. The method has not been validated, therefore it is necessary to validate the method to confirm that the method fit for its intended use. Leaf samples showing chlorotic symptom was obtained from Bogor and Bekasi, West Java and used for test samples. These samples was differentiated into 2 groups, i.e. leaf midrib and leaf mesophyll. Validation test involved homogenicity, and reproducibility test; each test was replicated 2 times. The test showed that using leaf midrib gave better result for detection of bacteria causing CVPD disease than using leaf mesophyll. Therefore, this method is recommended as routine detection method for bacteria causing CVPD disease
Deteksi dan Identifikasi Cendawan Terbawa Benih Brassicaceae
Seed quality is very critical in agricultural production, especially to gain high yield and reduce disease problems in the field. New diseases or pathogens is potentially entering a country through seed movement by import activity. This study aimed to detect and identify seed-borne fungi from Brassicaceae seeds imported from the United States and Malaysia. Seeds were incubated on 5 sheets of wet blotting paper at a temperature of 27–30 °C for 14 days following surface sterilization. Each fungus that grows on the seed was isolated on potato dextrose agar and malt extract agar for further morphological identification. The three fungi most commonly found either on the seed with or without surface-sterilization were Aspergillus flavus, Curvularia lunata and A. niger. All of the fungi were a potential pathogen in the family Brassicaceae seeds and seedlings. Important pathogen in Brassicaceae crops, i.e. Phoma lingam was also found in small amounts and only on white pak choy seeds
Deteksi dan Identifikasi Dickeya sp. sebagai Organisme Pengganggu Tumbuhan Karantina A2 pada Tanaman Kentang di Jawa
Erwinia chrysanthemi (currently Dickeya sp.) is one of the A2 quarantine pest that must be concerned of its distribution on potato in Indonesia. The aim of this study is to detect and identify E. chrysanthemi from potato in Java. A total of 400 samples of potato plants showing symptoms of soft rot were obtained from several potato areas in Pangalengan and Garut (West Java), Dieng (Central Java), and Batu-Malang (East Java). Disease incidence was determined by indirect enzyme-linked immunosorbent assay (I-ELISA) using polyclonal antiserum. E.chrysanthemi was isolated from plant samples with positive ELISA results. Furthermore, bacterial isolates were characterized by GEN III OmniLog ID System and PCR using specific primers Ec3F/Ec4R, as well as the universal 16S rRNA primer pair of 27F/1429R. The incidence of E. chrysanthemi based on ELISA was obtained. Based on physiological characters; Gram, catalase, oxidase, and oxidation-fermentation, there were 4 isolates similar to the genus of Erwinia. However, the results of Gen III OmniLog System, PCR, and nucleotide sequences analysis of 16S rRNA confirmed that none of the isolates were identified as E.chrysanthemi. Otherwise, those 4 isolates were identified as Pseudomonas oryzihabitans, Pantoea agglomerans, and Pseudomonas viridiflava. The result of this study indicated that the existence of E. chrysanthemi as an A2 quarantine pest on potato in Java can not be confirmed and remains as an A1 quarantine pest
Formulasi Bakteri Endofit Akar Kedelai untuk Pengendalian Pustul Bakteri
Two isolates of bacterial endophyte from soybean root were found to be effective to control bacterial pustule caused by Xanthomonas axonopodis pv. glycines. Formulation of the bacterial isolates is required to maintain the effectivity of this bacterial isolates during storage, transportation and application. The aim of this research was to obtain the best carrier for formulation to maintain the effectivity of bacterial endophyte in storage to control bacterial pustule on soybean. Three kind of carrier agent was evaluated for formulation of bacterial endophyte i.e. peat soil, tapioca flour and coconut water + 1% palm oil. Each carrier agent was combined with 5 treatment of storage time i.e. 0, 1, 3, 5 and 7 weeks. Soybean plants was inoculated by. X. axonopodis pv. glycines 2 weeks after planting by rubbing bacterial suspension (106 cel mL-1) on lower surface of leaves. The results showed that all formulas of bacterial endophyte were able to suppress the bacterial pustule on soybean. The best formulations were bacterial endophyte in peat soil stored for 1 and 7 weeks (effectivity rate 79.85% and 77.02%) and coconut water + palm oil and storaged for 3 weeks (effectivity rate 77.46%)
Perlakuan Panas Kering dan Bakterisida untuk Menekan Infeksi Pantoea stewartii subsp. stewartii pada Benih Jagung Manis
Stewart’s Wilt is an important bacterial disease of sweet corn caused by Pantoea stewartii subsp. stewartii (synonim Erwinia stewartii). This bacteria is a seed transmitted pathogen therefore seed treatment is one method to control stewart’s wilt. The aim of this research was to study the effectiveness of dry heat, bactericide treatment, and their combinations to eliminate P. stewartii subsp. stewartii infection on sweet corn seed without damaging seed quality. The research was conducted in 3 experiments. Experiment I was conducted to determine the treatment window of dry heat and bactericide treatment. The treatment was carried out on sweet corn seed using the P. stewartii subsp. stewartii in vitro. Experiment II was conducted to study dry heat and bactericide treatment on sweet corn seed infested by P. stewartii subsp. stewartii. Experiment III was conducted to study combination of dry heat and bactericide treatment on sweet corn seed infested by P. stewartii subsp. stewartii. The results showed that dry heat treatment at 50 °C for 24 hours was able to eliminate pathogen populations in vitro but was unable to eliminate the 128 pathogen on infected seed (in vivo). Germination tests indicated that seed treatments with dry heat up to 55 °C did not decrease the germination level. The use of bactericide treatment in 100 ppm could reduce the population of bacteria on sweet corn seeds. Bactericide concentration of 150 and 200 ppm could decrease the population of bacteria on sweet corn seeds, however it could cause phytotoxic effect. The combination of bactericide (100 ppm, w/v) ) with dry heat treatment (55 °C for 24 hours) was able to eliminate bacteria on infected seed with seed germination above 85%
Aktivitas Anticendawan Bacillus cereus 11UJ terhadap Rhizoctonia solani dan Pyricularia oryzae
Microbial secondary metabolites is an important resource for antifungal development in disease control strategy. The objective of this study was to screen Bacillus cereus 11UJ, an antagonistic rhizosphere bacteria for potential secondary metabolite production against rice fungal pathogens, i.e. Rhizoctonia solani and Pyricularia oryzae. The antagonistic effect of crude exract was evaluated using sterile filter paper discs on PDA medium. The ethyl acetate extracts of the bacterium showed a better antifungal activity to P. oryzae than those of R. solani. The inhibitory effect of the filtrate proved the potency of the isolates to produce antifungal. Analysis of pyrolysis gas chromatography-mass spectrometry showed that B. cereus 11UJ produces 3 major compounds i.e; 9,19-cyclolanostan-3-ol, acetate, (3.beta.)- (CAS) cycloartanyl acetate (13.14%); 4-(2’,2’-dimethyl-6’-methyliden-1’-cyclohexyliden)-3-methyl-2-butanone (9.72%); and stigmast-5-en-3-ol oleat (9.09%) which suggested to play an important role in the suppression of rice fungal pathogens.
Penapisan Cendawan Antagonis Indigenos Rizosfer Jahe dan Uji Daya Hambatnya terhadap Fusarium oxysporum f. sp. zingiberi
Ginger rot disease caused by Fusarium oxysporum f. sp. zingiberi is difficult to control because the pathogen is soil borne and is able to form clamidospore as resting structure. The aim of this study was to obtain indigenous antagonistic fungi from ginger rhizosphere which is potential for suppressing the growth of F. oxysporum f. sp. zingiberi. Fungi isolated from ginger rhizosphere were subjected for antagonism assay using dual culture method. Fungi isolates showed capability to inhibit F. oxysporum f. sp. zingiberii were then identified based on morphology characters. Eleven isolates were successfully isolated, but only 9 isolates showed the potentials of suppressing the growth of F. oxysporum f. sp. zingiberi. All 9 isolates i.e. AB4, GC1, BB1, AB1, AB2, K12, GC3, K11 and GC2 had antibiosis activity, and 3 isolates among them i.e. AB2, BB1 and K11 showed competition mechanism. Based on morphology characters the isolates were identified as Penicillium spp. (4 isolates), Trichoderma spp. (3 isolates), and Aspergillus spp. (2 isolates)