Oxysporum Pathogen Research Articles

Modulation of plant defenses by Jasmonic acid and salicylic acid in Capsicum annuum L. against Fusarium wilt in response to Fusarium oxysporum pathogen

Wilt disease in chilli caused by Fusarium oxysporum is a serious and global issue in chilli production, necessitating greater knowledge of plant defense systems for overall disease protection and management. In an eco-friendly integrated agricultural protection system, the introduction of chemical elicitors like jasmonic acid (JA) and salicylic acid (SA) represents an attractive new prospect means of controlling bacterial and fungal diseases. In the present study effectiveness of JA and SA as elicitors in disease progression was investigated in Capsicum annuum L. c.v., Kashmiri longum (chilli) plants against Fusarium wilt caused by pathogen Fusarium oxysporum. The experiment had eight sets of plants as control (untreated, uninfected), infected (untreated, infected), and one set of plants for each concentration of JA treatment (50 µM, 100 µM, 150 µM) + pathogen, and SA treatment (50 µM, 100 µM, 150 µM) + pathogen. Pre-treatment of JA and SA elicitors to F.oxysorum-infected chilli plants showed significant decrease in disease severity index as well as in disease symptoms compared to pathogen-infected and control plants. There was a substantial increase in the activities of antioxidant and defense enzymes in elicitor treated samples post pathogen inoculation. Exogenous application of JA and SA enhanced the growth of morphological parameters (shoot length, root length, number of leaves, leaf area, and plant height). Moreover, the statistical analysis using two-way ANOVA and Tukey test revealed significant differences between treatments, and days post infection in comparison to control. The study found that each elicitor treatment significantly differs in the type of enzymes activated and their amounts post-inoculation, indicating distinct host reaction patterns. Overall, the current study highlights the induced defense resistance role of JA and SA in chilli plants in response to F.oxysporum and JA was found most effective concerning disease protection followed by SA.

Antifungal activity of clove (Eugenia caryophyllata) extract against Fusarium oxysporum cutinase enzyme in Tomato (Solanum lycopersicum) from in vitro study

Fusarium oxysporum f.sp. lycopersici presents a notable threat to tomato plants due to the hydrolytic activity of its cutinase enzyme, which facilitates the penetration of plant root tissues. Thus, reducing cutinase activity through the application of cloves as inhibitors offers an environmentally friendly alternative to hazardous chemical fungicides, showing great promise in controlling Fusarium wilt disease, particularly by targeting the cutinase enzyme of Fusarium oxysporum. This study involved GC-MS analysis of clove extract, fungal growth and cutinase activity assay using rhodamine-b olive oil media. Hence, this study aims to reveal the potential and mechanism of clove extracts as inhibitors of cutinase enzymes to reduce the penetration of the Fusarium oxysporum pathogen in tomato plants. The result shows that clove extract, containing approximately 20% antifungal compounds primarily eugenol (11% of total peak area), inhibits Fusarium oxysporum growth. It also reduces the hydrolytic activity of cutinase crucial for fungal penetration, evidenced by decreased fluorescence halos in tests with rhodamine-B and olive oil media under UV light after adding 1%, 2%, and 3% clove extract. Further in vivo studies are needed to explore its direct effects as a plant inhibitor.

In vitro antifungal activities of dose-dependent bioactive compound from potato peels to combat powdery mildew disease in cucumber

The search for biopolymer-based materials to replace dangerous chemicals in agriculture has become increasingly important in recent years for sustainable crop development. In our study enzymatic synthesis of isomaltose was done using potato peels. Isomaltose solvent extracts were tested for their ability to inhibit fungal pathogens like Erysiphe cichoracearum and Fusarium oxysporum. Among those tested, a dosedependent isomaltose extract exhibited significant inhibition on E. cichoracearum and F. oxysporum pathogen conidial sporulation, number of conidia and their motility. Under the in vitro studies, with isomaltose extract at (2.5 mg mL ) recorded a maximum conidial inhibition of 86.2, ?1 E. cichoracearum average number of conidia 4-27 and 5 per cent motility. While, sterile distilled water and DMSO showed maximum growth of the both the pathogens and also their motility was 92-97 per cent, respectively. Similarly, F. oxysporum maximum conidial inhibition of 88.3 and average conidia of 9-30 with motility of 7 per cent was observed after treating with 2.5 mg mL isomaltose. Moreover, isomaltose a biopolymer ?1 derived from potato peel was used in different concentrations as priming agent to cucumber seeds and were evaluated for its effectiveness to enhance plant growth parameters. Among the treatments, seeds-primed with 2.5 mg mL of isomaltose extracts in water exhibited early seedling germination of 96.8 per cent and ?1 vigor of 2210.3 and also cucumber seeds treated with 2.5 mg mL of isomaltose extracts in DMSO showed ?1 significant germination rate of 95.5 per cent and vigor index of 1987.7. Overall, these results determine that the antifungal property of water dissolved isomaltose is highly significant in exhibiting remarkable inhibitory action against Fusarium and powdery mildew phytopathogens, further the dose-dependent concentration of water dissolved isomaltose showed fair to good enhancement of seed germination which will lead to establishing a novel bio-waste agricultural formulation for the management of plant pathogens and in particular Fusarium and powdery mildew disease of cucumber and other cucurbitaceous crops.. KEYWORDS :Bio-polymer, optimize, pathogen inhibition, plant growth, seed treatment

In vitro antimicrobial, antioxidant and molecular study of Nostoc punctiforme isolated from the rice field

Cyanobacteria are photosynthetic prokaryotes and are reservoir of bioactive compounds having substantial antimicrobial and antioxidant activity. They serve as a rich source of structurally novel and biologically active metabolites, holding great potential for various pharmaceutical applications. The aim of this study is to investigate in vitro antimicrobial and antioxidant activities of the extracts of Nostoc punctiforme, a filamentous heterocystous cyanobacterium predominant in the rice fields of Lakhanpur (Bargarh District), Odisha. The heterocystous cyanobacteria was collected from rice field and identified by means of morphological and molecular approach (Nostoc punctiforme Jbr02). Subsequently, in vitro antimicrobial and antioxidant activity was assayed using acetone, methanol, and benzene extract. The cyanobacterial extracts established important antimicrobial actions against bacterial and fungal pathogens with significant MIC values from 62.5 to 500 μg/ml. The methanolic extract displayed better inhibitory activities against both V. Cholerae and P. verrucosun with the MIC value 62.5μg/ml while no such activity was recorded in benzene extract against B. subtilis, A. niger and F. oxysporum pathogens. The antioxidant study, depicted that the methanolic extract showed relatively higher antiradical activity of IC50 542±0.012 μg/ml among the three solvents. The Ferric reducing assay result was also maximum in methanolic extract (0.478±0.78) as compared to benzene and acetone extract. These findings infer that Nostoc punctiforme has potential antimicrobial and antioxidant activity, unveiling its potential as a valuable source of bioactive compounds. Thus, N. punctiforme in specific and cyanobacteria in general are one of the most promising candidates for commercial applications.

Diversity, Characterization, and Potential Applications of Bacterial Endophytes Isolated from the Halophyte Limonium axillare

Recently, there has been a worldwide call to explore nature-friendly compounds, which could enhance plant growth and substitute for chemically synthesized products. Endophytes are a group of microorganisms that lives in the plants and algae symbiotically. In this research, endophytes were isolated from leaves of the halophyte, Limonium axillare. A total of 280 bacterial isolates were obtained from the leaves of L. axillare. Strains displaying similarities in terms of morphology and biochemical reactions were categorized into 48 groups. One representative from each group was identified and subjected to enzymatic and plant growth-promoting tests. Forty-eight isolates were identified using a sequence similarity-based method based on the 16S rDNA gene. The identified strains were categorized into two genera: Bacillus and Staphylococcus. Our investigation uncovered 44 isolates from the Bacillus genus, representing 10 different species, including Bacillus sp., B. pseudomycoides, B. cereus, B. paramycoides, B. velezensis, B. subtilis, B. thuringiensis, B. wiedmannii, B. anthracis, and B. bacterium. Furthermore, we observed that only 4 isolates belonged to the Staphylococcus genus, encompassing 3 distinct species: S. bacterium, S. succinus, and S. saprophyticus. The isolated bacteria were screened for extracellular enzymes, plant growth promoting traits, antifungal activity, and salinity tolerance. From the previous screening, diverse responses were obtained. Most of the isolates were secreted at least one of the hydrolysis enzymes (protease, lipase and amylase). (93.8%) of the strains showed phosphate solubilization activity. (33.3%) produce (IAA). Siderophore production potential was present in 91.7% of isolates, while ACC deaminase and HCN production activities were identified in 52.1 and 41.7% of strains, respectively. Additionally, DNase activity was evident in 27.1%, and ammonia production was observed in 31.3% of the isolates. The isolates Bacillus velezensis (AL4QUA) strain showed positive effect in the greenhouse experiment in terms of plant growth promoter agent and biocontrol agent against Fusarium oxysporum pathogen of tomato seedling. Thus, endophytes have the potential to reduce chemical inputs in conventional agricultural practices, increase nutrient uptake and improve plant stress resilience.

Structural and Functional Analysis of the Bacterial Community in the Soil of Continuously Cultivated Lonicera japonica Thunb. and Screening Antagonistic Bacteria for Plant Pathogens

Continuous cropping is the main form of cultivation in Chinese agriculture. The bacterial community plays an important role in maintaining the healthy growth of plants. However, there are few reports on the composition and dynamics of the bacterial community structure under continuous cropping of Lonicera japonica Thunb. High-throughput sequencing was used to monitor the variation in the soil bacterial community structure of different monocropping years of Lonicera japonica Thunb., as well as the correlation between soil characteristics and bacterial community. Meanwhile, antagonistic bacteria for Fusarium oxysporum pathogens were isolated and functionally verified by culture-dependent techniques and pot experiments. Bacterial community diversity and structure changed significantly with the increase in the years of Lonicera japonica Thunb. succession. However, some beneficial bacteria, such as Bacillus and Nitrosospira, were gradually depleted. The complexity of the bacteria co-occurrence networks decreased with increasing years of cropping. FAPROTAX-based functional prediction showed that the abundance of genes related to carbon, nitrogen, sulfur metabolism and chitinlysis were reduced with the extended crop succession. Furthermore, the three Bacillus strains that were strongly antagonistic toward Fusarium oxysporum and the pot experiment demonstrated they significantly promoted Lonicera japonica Thunb. growth. Our research provides theoretical support for the development of microbial fertilizers that are beneficial to plants.

Synthesis and antifungal activity of copper nanoparticles against Fusarium oxysporum pathogen of plants

For many decades, Cu2+ ions have been used as fungicides in agriculture. However, the accumulation of Cu2+ ions in the soil ecosystem will be disadvantage for environment. Thus, the substitution of copper nanoparticles for Cu2+ ion is necessary to develop long-term efficient, eco-friendly, and cost-effective fungicides. In this study, the copper nanoparticles were synthesized by chemical reduction method of Cu2+ with reductive agent of NaHB4 in chitosan stabilizer. Characterizations of copper nanoparticles were determined by UV–vis spectra, Fourier transform infrared spectroscopy, X ray diffraction patterns and Transmission Electron Microscopy images. The antifungal efficacy of CuNPs was evaluated by testing against Fusarium oxysporum fungi at various concentrations from 20–100 ppm. The results revealed that copper nanoparticles samples inhibited significantly the growth of Fusarium oxysporum and the smaller diameter is, the higher antifungal efficacy is. The copper nanoparticles with 26.5 nm expressed an antifungal efficacy is higher than copper nanoparticles with 29 nm. The complete inhibition was observed at concentrations ≥ 80 ppm after 1 day and even 7 days of incubation for 2.0 CuNPs (26.5 nm) sample while fungi still survive on PDA plates containing 1.5 CuNPs (29 nm).

Selection of rhizosphere communities of diverse rotation crops reveals unique core microbiome associated with reduced banana Fusarium wilt disease.

Crop rotation can assemble distinct core microbiota as functionally specific barriers against the invasion of banana Fusarium oxysporum pathogens. However, the taxonomic identity of rotation-unique core taxa and their legacy effects are poorly understood under field conditions. Pepper and eggplant rotations were employed to reveal rotation crop- and banana-unique antagonistic core taxa by insitu tracking of the soil microbiome assembly patterns for 2 yr. The rotation crop-unique antagonistic taxa were isolated and functionally verified by culture-dependent techniques, high-throughput sequencing, and pot experiments. Pepper and eggplant rotations resulted in eight and one rotation-unique antagonistic core taxa out of 12 507 microbial taxa, respectively. These nine antagonistic taxa were retained the following year and significantly decreased banana wilt disease incidence via legacy effects, although the cultivated strains were exclusively of the genera Bacillus and Pseudomonas. The fermentation broth and volatiles of these two taxa showed strong antagonistic activity, and pot experiments demonstrated high suppression of wilt disease and significant promotion of banana growth. Our study provides a mechanistic understanding of the identification of rotation crop-unique antagonistic taxa and highlights the importance of targeted cultivation of beneficial microorganisms for optimizing crop rotation-based scenarios in support of banana agriculture sustainability.

Response of Microorganism Suspension and Various Kinds of Organic Fertilizers to the Development of Pathogen Fusarium sp. on Shallots

Shallot (Allium ascalonicum L) is one of the horticultural plants that acts as a natural antioxidant. Shallot's productivity in Indonesia is relatively low. It is influenced by various factors, one of which is due to the attack of a soil-borne pathogen, namely Fusarium oxysporum. Symptoms of Fusarium oxysporum pathogen attack are yellow or pale green leaves and more elongated growth. Severe attack leads plant to death. Balanced fertilization and biopesticides application can prevent Fusarium wilt. This study aims to reduce and control Fusarium wilt disease. The research method used was the Split Plot Design method which consisted of two factors with the main plot, namely the application of suspension of microorganisms (S) which consists of two levels, namely fungicide application (S0) and Fobio application and the sub-plot, namely the application of various organic fertilizers (M) which consists of three levels, namely control (chemical fertilizer) (M0), chicken manure (M1), and Piensbio organic fertilizer (M2). Observation data for each treatment will be analyzed using analysis of variance (ANOVA) followed by the Duncan test (alpha 5%) if there were differences in each treatment. The results of this study, the main plot treatment, fungicide application (S0), showed an incubation period of 29 days and an average intensity of disease attacks of 4.2%. The treatment of subplots, a type of organic fertilizer (M), is unable to suppress the intensity of the attack and slow down the incubation period of the Fusarium sp on shallot crops. There was no interaction between the treatment of the main plots and the subplots on all the observation parameters.

Morpho-molecular Identification and Pathogenicity of Fusarium oxysporum Pathogens Associated with Vascular wilt in Cowpea (Vigna unguiculata L.)

Fusarium oxysporum (Fo), causes vascular wilt in cowpea is a serious pathogen, which leads to severe yield loss and high plant mortality. Variability among the pathogen is very low, due to the lack of sexual reproduction, and low mutation rate. In this study ten different isolates of Fo, collected from various of locations, were evaluated and tested for morphology, molecular biology, and pathogenicity as well. Fo consists of asexual spores, macroconidia, microconidia and chlamydospores, with varied dimensions and produced some pigments in culture media. Sand maize media (10%) was used in pathogenicity test and was found the best than other methods for screening Fo in cowpea. The Fo DNA were amplified with Internal Transcribed Spacer (ITS) primer and the obtained sequences were deposited in the gene bank (GenBank) database. The sequences were compared with the available database and showed 99-100% homology with Fo. Whereas, the phylogenetic study revealed that the isolates were not distant from Fusarium species. The phylogenetic analysis helps to understand the evolutionary relationship among the species identified.

Biocontrol Activity of Nonpathogenic Strains of Fusarium oxysporum: Colonization on the Root Surface to Overcome Nutritional Competition.

Fusarium oxysporum is a soil-borne fungal pathogen that causes vascular wilts in a wide variety of crops. Certain nonpathogenic strains of F. oxysporum are known to protect crops against F. oxysporum pathogens. We assessed the biocontrol activities of nonpathogenic mutants of F. oxysporum ff. spp. melonis and lycopersici generated by disruption of the FOW2 gene, which encodes a Zn(II)2Cys6-type transcriptional regulator essential for their pathogenicity. Pre-inoculation of melon or tomato roots with strain ΔFOW2 conidia markedly reduced disease incidence caused by the parental wild-type strain in a concentration-dependent manner of conidial suspensions of ΔFOW2 strains. The biocontrol effect caused by the ΔFOW2 pre-inoculation lasted for at least 7 days. Pre-inoculation of melon roots with the wild-type or ΔFOW2 strain of F. oxysporum f. sp. lycopersici and nonpathogenic F. oxysporum strain also led to biocontrol activity against F. oxysporum f. sp. melonis, indicating that the biocontrol activity of ΔFOW2 strains is due to its nonpathogenic nature, not to the FOW2 disfunction. Conidial germination and hyphal elongation of only the wild-type strain were inhibited on melon root surface pre-inoculated with conidia of strains nonpathogenic to melon plants. Expression of defense-related genes was not significantly induced in roots and aboveground parts of melon seedlings preinoculated with ΔFOW2 conidia. Carbon source competition assay showed that nonpathogenic strains competed with the wild-type strain for a carbon source in soil. Strain ΔFOW2 also competed with the oomycete pathogen Pythium aphanidermatum for carbon source and protected melon plants from P. aphanidermatum. Our results suggest that the biocontrol activity of the nonpathogenic F. oxysporum strains used in this study mainly depends on their extensive colonization of the root surface and outcompeting pathogens for nutrients.

Host range studies of Fusarium oxysporum, causal agent of seedling wilt disease of Acacia mangium

Abstract. Soleha S, Muslim A, Suwandi S, Kadir S, Pratama R. 2021. Host range studies of Fusarium oxysporum, causal agent of seedling wilt disease of Acacia mangium. Biodiversitas 23: 25-32. Fusarium oxysporum is a serious pathogen that causes severe wilt disease in commercial nurseries of Acacia mangium in South Sumatra, Indonesia. This study aimed to investigate the host range of F. oxysporum as a nursery wilt pathogen in A. mangium and several forest and industrial plants. Three isolates of F. oxysporum with different translation elongation factor (tef 1-a) sequences were tested for pathogenicity on different fabaceae family plants and the growth of population was also observed. The results showed that all the three isolates were able to infect all the tested plants with different reactions of wilt disease. The Acacia crassicarpa and Falcataria moluccana were highly susceptible; Archidendron pauciflorum, Leucaena leucocephala, and Parkia speciosa were moderately vulnerable and Acacia auriculiformis was moderately resistant. The pathogen population in A. crassicarpa and F. moluccana grew rapidly along with the increase in disease scores, while in L. leucocephala it was moderate, and slow in A. pauciflorum, P. speciosa and A. auriculiformis plants. In conclusion, F. oxysporum pathogen, which was isolated from A. mangium, has a wide range of hosts in the fabaceae family.

Current progress on pathogenicity-related transcription factors in Fusarium oxysporum.

Fusarium oxysporum is a well‐known soilborne plant pathogen that causes severe vascular wilt in economically important crops worldwide. During the infection process, F. oxysporum not only secretes various virulence factors, such as cell wall‐degrading enzymes (CWDEs), effectors, and mycotoxins, that potentially play important roles in fungal pathogenicity but it must also respond to extrinsic abiotic stresses from the environment and the host. Over 700 transcription factors (TFs) have been predicted in the genome of F. oxysporum, but only 26 TFs have been functionally characterized in various formae speciales of F. oxysporum. Among these TFs, a total of 23 belonging to 10 families are required for pathogenesis through various mechanisms and pathways, and the zinc finger TF family is the largest family among these 10 families, which consists of 15 TFs that have been functionally characterized in F. oxysporum. In this review, we report current research progress on the 26 functionally analysed TFs in F. oxysporum and sort them into four groups based on their roles in F. oxysporum pathogenicity. Furthermore, we summarize and compare the biofunctions, involved pathways, putative targets, and homologs of these TFs and analyse the relationships among them. This review provides a systematic analysis of the regulation of virulence‐related genes and facilitates further mechanistic analysis of TFs important in F. oxysporum virulence.

Molecular characterization of Fusarium solani and Fusarium oxysporum phyto-pathogens causing mango maturity malconformation

Mango (Mangifera indica L.) is a significant fruit on global scale and is vulnerable to varied kinds of the decline disorders, subsequently leading to the immense economic loss of the mango growers in different countries. Pakistan is a renowned exporter of auspicious varieties of the mango fruit. However, the mango fruit in Pakistan is also exposed to a number of phyto-pathogens. Current work has carried out the task of the fungal species identification involved in post-harvest rotting of mango in orchards by cultural and pathological characteristics as well as molecular technique. By molecular analysis, the genetic diversity of Fusarium species (Fusarium solani, Fusarium oxysporum) was isolated from the rotten mango fruits of the selected districts and evaluated by 5.8S and two ITS flanking regions ITS1 and ITS2 gene of rDNA. Molecular analysis facilitated the identification of the varied kinds of the isolated pathogens and also determined the relationship of various Fusarium strains involved in post-harvest diseases leading to the malconformation of mangoes. Prior to the current research, anthracnose has been reported to be the major mango rotting disease caused by Colletotrichum gloeosporides in Pakistan. However, the results of our work are indicative of the profound involvement of the F. solani and F. oxysporum in destroying the mango crop. Current work is indicative of the opportunist nature of the F. solani and F. oxysporum pathogens infecting post-harvest mangoes through wounds and cause injuries.

Establishment of the Causal Agent(s) of Spike Shedding and Stem Wilting of Pepper (Piper nigrum L.) in Morogoro District, Tanzania

Pepper (Piper nigrum L.) serves as a source of income to smallholder spice farmers in Morogoro district of Tanzania. Recently, spike shedding and stem wilting of pepper plants were reported to cause about 30% yield loss of the crop. This study was undertaken to identify the causal agent(s) of the problems. Three pepper gardens in each of the four hamlets (Nyange, Doga, Tandai, and Lukenge) in Tandai village (Kinole ward) were surveyed, and plant tissue and soil samples were collected for laboratory analysis. An experiment was laid out in a randomized complete block design with three replications. Pepper cultivars, Babu kubwa, Babu ndogo, Babu kati, and Ismailia grown in the study area, were used as treatments for evaluation of the prevalence of spike shedding and stem wilting. Treatments mean separation was conducted based on Duncan’s multiple range test atp=0.05. Regression (R2) and simple correlation (r) analyses between stem wilting (incidence and severity) and termite pest infestation were performed. The identified pathogen in most of the soil and plant tissue samples was Fusarium oxysporum. The nutrients, N, P, Mg, and Cu, concentration in soil and leaf samples was below the optimal ranges. Termite attacks were significantly high in some farmer’s gardens where up to 50.5% of the pepper plants was damaged. Hence, a significant positive correlation was observed between termite pest infestation in gardens and both incidence (r = 0.881, R2 = 0.74,p<0.001) and severity of stem wilting (r = 0.918, R2 = 0.84,p<0.001) of pepper plants. Most of the termite attacks and damages (70%) were observed on pepper plants supported on silver oak, unlike those trained on Jatropha. A higher percentage of undeveloped berries (36%) and intermediate-size berries (34%) was recorded on cultivars “Babu kati” and “Babu kubwa,” respectively. Multiple factors have been associated to be the causes of spike shedding and stem wilting of pepper, which could be used to develop appropriate control solutions useful to farmers. Confirmation of F. oxysporum pathogenicity is recommended. A comprehensive study is suggested on the repellent or lethal activities of Jatropha against F. oxysporum and termites. Furthermore, studies through field experiments are needed to generate site-specific soil nutrient improvement recommendations and design an integrated approach to control F. oxysporum and termites and to determine existing alternative host plants for these pests.

Competition of biological agents of Streptomyces sp, Gliocladium sp, and Trichoderma harzianum to Fusarium oxysporum in Tomato Rhizophere

Fusarium oxysporum is a soil-borne fungus that attacks all stages of tomato plant from seedlings to mature plants. The disease occurrence on the tomato nursery can lead economically loss due to its fast and massive damage. Application of effective biological control agents is considered as promising control measure of the disease. The aim of this study was to evaluate the potential competitiveness of biological agents mixture consisting of Streptomyces sp., Gliocladium sp. and T. harzianum against F. oxysporum f. sp. lycopersici in the rhizosphere of the tomato plant. The experiment was arranged in completely randomized design with five treatment types of agents that a single biological agents Streptomyces sp. (S), a mixture of Streptomyces sp. and Gliocladium sp. (SG), a mixture of Streptomyces sp. and T. harzianum (ST), a mixture of Streptomyces sp., Gliocladium sp., and T. harzianum (SGT) and control without biological agents. Each treatment was replicated four times and consisted of 6 plants for observation purposes destructively. Descriptive analysis conducted on the pattern of colonization of the roots competition showed a growth pattern colonization of biological agents, Streptomyces sp , Gliocladium sp , T. harzianum and F. oxysporum pathogen (SGTF) was the same growth pattern of SGF and STF, where four of the microbes grew on the same side of roots as fungal pathogens, in all parts of the root sprouts. Given biological agent Streptomyces sp, Gliocladium sp., dan Trichoderma harzianum decreased fusarium wilt diseases severity of tomato. Weight root of tomato plants was applied by biological agents was 9.2 g greater than plant without biological agents, which were 2.5 g. The observation on tomato indicated root colonization occurs, especially on the base of the stem-roots by a mixture of biological agents T. harzianum and Gliocladium sp.

Biocontrol of wilt-inducing Fusarium oxysporum by aqueous leaf extract from Egyptian Ammi majus and Ammi visnaga

than those of A. visnaga. This study suggests efficiency of Ammi leaf extracts in suppression of Fusarium oxysporum pathogenicity.

Inhibitory Power Test of Two Trichoderma Isolates in In Vitro Way Againts Fusarium oxysporum The Cause of Red Chilli Stem Rot

This study aims to determine the control power of two isolates of Trichoderma obtained from the forest floor soil to the activity of Fusarium oxysporum pathogen causing stem rotation of red chili plant in vitro. The experiment was arranged in complete randomized design using 3 kinds of treatment of Trichoderma sp., T. harzianum isolate and control (without Trichoderma fungi isolate) tested for its antagonistic ability against pathogen; each treatment was repeated 4 times. The observed variable is pathogen inhibition (%). The observational data were analyzed by using variance followed by 5% HSD test to know the difference between treatments. The results showed that T. harzianum (Tc-Jjr-02 isolate) and Trichoderma sp. (Tc-Pjn-01 isolate) were able to inhibit F. oxysporum pathogens respectively 76.9% and 77.1% at 108 hours after inoculation. Both of these Trichoderma fungal isolates can be developed into biocontrol agents for F. oxysporum.

Uji Antagonisme Trichoderma harzianum Dan Azotobacter chroococcum Terhadap Rhyzoctonia solani, Sclerotium rolfsii dan Fusarium oxysporum secara in-vitro

Damage to plants by pathogenic fungi is often found in nurseries and field. Biological control offers a promising alternative for managing diseases in plants because they are environmentally friendly compared to pesticides. The aim of the study was to test the power of the antagonism of Trichoderma harzianum and Azotobacter chroococcum on solid organic media "TRIAZOTE" which had been stored for five months against R. solani, S. rolfsii, and F. oxysporium pathogens. In-vitro treatment tested the power of antagonism of T. harzianum and A. chroococcum on growth of R. solani, S. rolfsii, and F. Oxysporum pathogens. The results showed that T. harzianum in "TRIAZOTE" which had been stored for five months could inhibit pathogenic growth R. solani, S. rolfsii, and F. oxysporum by 54.57%, 66.22%, and 68,57% respectively. While A. chroococcum did not significantly inhibit pathogenic growth of R. solani (11.02%), S. rolfsii (9.09%) and F. oxyprorum (10.99%). To control the disease in plants, especially those caused by soil borne pathogens R. solani, S. rolfsii and F. oxyprorum, can use biological fertilizer "TRIAZOTE" even though it has been stored for five months

Correlation between Soil Phospor (P) Content and Soil Yeast Antagonistics Ability Against Fusarium oxysporum Pathogen Causing Wilt

Besides its role during fermentation process, yeast also has potential as biological agent because of its antagonistics characteristic. We have isolated yeast from six different locations based on Phospourus differences. Isolated yeast were then tested its antagonistics ability of Fusarium oxysporum, the pathogen causing tomato wilt disease. This research aims to find out the diversity of yeast found in the tomato rhizosphere in six different contents of phosphorus locations and to know its antagonistics ability against the pathogenic. F. oxysporum. This research was conducted in the Laboratory of Mycology, Department of Pests and Diseases, Faculty of Agriculture, Brawijaya University, Malang and in the Chemistry Laboratory, Institut Teknologi 10 Nopember Surabaya, started from January up to September 2015. Yeasts have been isolated from tomato’s rhizosphere of 6 different locations around East Java proviences. The result showed that yeasts from organic field (Lower P content) were 6 genera. They are Candida sp. 1, Pichia sp. 1, Hansenula sp., Metschnikowia sp. 1, Cryptococcus sp., and Zygosaccharomyces sp. While the yeasts from inorganic field (higher P) were 3 genera. The most potential yeast in controlling F. oxysporum is Pichia sp. 2. Lower P content showed more divers than higher P content. Yeasts from higher soil P content showed more antagonists to control F. oxysporum. Keywords: Phosphor, correlation, yeast, antagonistic, disease, soil