Biological control of Fusarium wilt of carnation with a nonpathogenic isolate of Fusarium oxysporum

1992 ◽  
Vol 70 (6) ◽  
pp. 1199-1205 ◽  
Author(s):  
J. Postma ◽  
H. Rattink
Keyword(s):  
Biological Control ◽  
Fusarium Oxysporum ◽  
Key Words ◽  
Disease Severity ◽  
Fusarium Wilt ◽  
Resistant Mutant ◽  
The Other ◽  
Susceptible Cultivar ◽  
Wild Type ◽  
Key Words Colonization

The nonpathogenic isolate 618-12 of Fusarium oxysporum, wild type as well as a benomyl-resistant mutant, suppressed Fusarium wilt (F. o. f.sp. dianthi) in a susceptible cultivar of carnation by 80%. Two other nonpathogenic isolates had a similar effect. Suppression by isolate 618-12 occurred only when antagonist and pathogen were both added to the soil but not if they were introduced at a different location (one in the stem, the other in the soil). Thus systemic induced resistance could not be demonstrated. In treatments where isolate 618-12 and the pathogen were both introduced into the soil, fewer plants showed symptoms, disease severity was less, and colonization by the pathogen was less extensive than after inoculation with the pathogen alone. After soil inoculation, the nonpathogenic isolate 618-12 was recovered from the stem, sometimes at a height of 60 cm. Key words: colonization, carnation stem, soil.

Biological control of Fusarium wilt of cucumber with nonpathogenic isolates of Fusarium oxysporum

1987 ◽  
Vol 33 (5) ◽  
pp. 349-353 ◽  
Author(s):  
T. C. Paulitz ◽  
C. S. Park ◽  
R. Baker
Keyword(s):  
Biological Control ◽  
Fusarium Oxysporum ◽  
Infection Rate ◽  
Fusarium Wilt ◽  
Disease Incidence ◽  
Infection Rates ◽  
Control Activity ◽  
Significant Difference ◽  
Cucumber Roots ◽  
Linear Regressions

Nonpathogenic isolates of Fusarium oxysporum were obtained from surface-disinfested, symptomless cucumber roots grown in two raw (nonautoclaved) soils. These isolates were screened for pathogenicity and biological control activity against Fusarium wilt of cucumber in raw soil infested with Fusarium oxysporum f. sp. cucumerinum (F.o.c.). The influence of three isolates effective in inducing suppressiveness and three ineffective isolates on disease incidence over time was tested. The effective isolates reduced the infection rate (R), based on linear regressions of data transformed to loge (1/1 – y). Effective isolate C5 was added to raw soil infested with various inoculum densities of F.o.c. In treatments without C5, the increase in inoculum densities of F.o.c. decreased the incubation period of wilt disease, but there was no significant difference in infection rate among the inoculum density treatments. Isolate C5 reduced the infection rate at all inoculum densities of F.o.c. Various inoculum densities of C5 were added to raw soils infested with 1000 cfu/g of F.o.c. In the first trial, infection rates were reduced only in the treatment with 10 000 cfu/g of C5; in the second trial, infection rates were reduced in treatments with 10 000 and 30 000 cfu/g of C5.

scholarly journals Non-Synergistic Effect of Trichoderma harzianum and Glomus spp. in Reducing Infection of Fusarium Wilt in Banana

Pathogens ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 43 ◽  
Author(s):  
Arfe Castillo ◽  
Cecirly Puig ◽  
Christian Cumagun
Keyword(s):  
Biological Control ◽  
Synergistic Effect ◽  
Fusarium Oxysporum ◽  
Fusarium Wilt ◽  
Trichoderma Harzianum ◽  
Root Weight ◽  
Biological Control Agents ◽  
Competitive Effects ◽  
Glomus Spp ◽  
Race 4

Philippine banana is currently threatened by Fusarium oxysporum f. sp. cubense Tropical Race 4 (FocR4). This study investigated the use of Trichoderma harzianum pre-treated with Glomus spp, as a means of managing Fusarium wilt on young ‘Lakatan’ banana seedlings. Results showed that Glomus applied basally significantly improved banana seedling growth with increased increment in plant height and pseudostem diameter and heavier root weight. The application of Glomus spp. alone offered 100% protection to the ‘Lakatan’ seedlings against FocR4 as indicated by the absence of the wilting symptom. A combination of T. harzianum and Glomus spp. also gave significant effect against Fusarium wilt through delayed disease progression in the seedlings but was not synergistic. Competitive effects were suspected when application of the two biological control agents on banana roots was done simultaneously.

Nucleation during primary succession in the Canadian Rockies

1993 ◽  
Vol 71 (8) ◽  
pp. 1093-1096 ◽  
Author(s):  
D. J. Blundon ◽  
D. A. MacIsaac ◽  
M. R. T. Dale
Keyword(s):  
British Columbia ◽  
Nitrogen Fixation ◽  
Key Words ◽  
Rocky Mountains ◽  
Primary Succession ◽  
The Other ◽  
Pioneer Species ◽  
Canadian Rocky Mountains ◽  
Successional Species ◽  
Key Words Colonization

A study of nucleation during primary succession was carried out on age sequences of communities at two sites in the Canadian Rocky Mountains: one at the Mount Robson moraines, British Columbia, the other at Southeast Lyell Glacier, Alberta. The study concentrated on the associations of species with the nitrogen-fixing plants Hedysarum boreale var. mackenzii at Mount Robson moraines and Dryas drummondii at Southeast Lyell Glacier because those plants might serve as nuclei for colonization by other species, thus facilitating succession. The data show that recruitment of later successional species is greater in patches of the two pioneer species, but the fact that recruitment takes place away from the plants also suggests that although there is nucleation, it is not necessary for succession at these sites. Key words: colonization, nitrogen fixation, nucleation, succession.

scholarly journals Mutations in oxyR Resulting in Peroxide Resistance in Xanthomonas campestris

2000 ◽  
Vol 182 (13) ◽  
pp. 3846-3849 ◽  
Author(s):  
Skorn Mongkolsuk ◽  
Wirongrong Whangsuk ◽  
Mayuree Fuangthong ◽  
Suvit Loprasert
Keyword(s):  
Amino Acid ◽  
Xanthomonas Campestris ◽  
Resistant Mutant ◽  
The Other ◽  
Single Amino Acid ◽  
Silent Mutation ◽  
Expression Vectors ◽  
Nucleotide Sequence Analysis ◽  
Wild Type ◽  
Single Amino Acid Change

ABSTRACT A spontaneous Xanthomonas campestris pv. phaseoli H2O2-resistant mutant emerged upon selection with 1 mM H2O2. In this report, we show that growth of this mutant under noninducing conditions gave high levels of catalase, alkyl hydroperoxide reductase (AhpC and AhpF), and OxyR. The H2O2 resistance phenotype was abolished inoxyR-minus derivatives of the mutant, suggesting that elevated levels and mutations in oxyR were responsible for the phenotype. Nucleotide sequence analysis of the oxyRmutant showed three nucleotide changes. These changes resulted in one silent mutation and two amino acid changes, one at a highly conserved location (G197 to D197) and the other at a nonconserved location (L301 to R301) in OxyR. Furthermore, these mutations in oxyRaffected expression of genes in the oxyR regulon. Expression of an oxyR-regulated gene, ahpC, was used to monitor the redox state of OxyR. In the parental strain, a high level of wild-type OxyR repressed ahpC expression. By contrast, expression of oxyR5 from the X. campestris pv. phaseoli H2O2-resistant mutant and its derivative oxyR5G197D with a single-amino-acid change on expression vectors activatedahpC expression in the absence of inducer. The other single-amino-acid mutant derivative of oxyR5L301R had effects on ahpC expression similar to those of the wild-type oxyR. However, when the two single mutations were combined, as in oxyR5, these mutations had an additive effect on activation of ahpC expression.

scholarly journals Biological management of fusarium wilt on tomato caused by Fusarium oxysporum f. sp. lycospersici by some plant growth-promoting bacteria

2020 ◽  
Author(s):  
Halima Z. Hussein ◽  
Shaker I. Al-Dulaimi
Keyword(s):  
Fusarium Oxysporum ◽  
Disease Severity ◽  
Fusarium Wilt ◽  
Wilt Disease ◽  
Systemic Resistance ◽  
Control Treatment ◽  
Plant Growth Promoting Bacteria ◽  
Tomato Plants ◽  
Fusarium Wilt Disease ◽  
Infection Percentage

AbstractChemical approaches have been applied to combat Fusarium wilt disease for a long time. Even though pesticides are effective in controlling the disease, they continue to damage the environment. Environmental-friendly approaches to manage plant disease are the goal of many studies recently. This study was conducted to assess the efficacy of some bio-agents in induction of systemic resistance in tomato plants as a management approach of Fusarium wilt disease caused by Fusarium oxysporum f.sp. lycopersici (FOL) under condition Plastic house. Results of the plastic house experiments showed that all treatments in decreased Fusarium disease percentage and severity on tomato, two bacterial combinations (Streptomyces sp. (St) and Pseudomonas fluorescence (Pf)) decreased the infection percentage and disease severity with 16.6% and 8.3%, respectively. Treatment with St reduced the infection percentage and disease severity with 33.3% and 22.8%, while the Pf treatment showed 41.6% and 31.2% reduction in infection percentage and disease severity, compared to 100% and 91.6% in the control treatment. Results of induced systemic resistance (ISR) biochemical indicators showed significant differences in tomato plants. Peroxidase and Phenylalanine-Ammonia-Lyase (PAL) activity and the Phenol content increased significantly 14 days after treatments compared to the control treatment, which contains only the fungal pathogen FOL.

scholarly journals Antagonisme Bacillus terhadap Infeksi Layu Fusarium pada Bibit Pisang Hasil Kultur Jaringan

2013 ◽  
Vol 15 (1) ◽  
pp. 21
Author(s):  
Hadiwiyono Hadiwiyono ◽  
Arief Widyantoro ◽  
Salim Widono
Keyword(s):  
Biological Control ◽  
Fusarium Oxysporum ◽  
Fusarium Wilt ◽  
In Planta ◽  
Physiological Character ◽  
Important Disease

<p>Fusarium wilt (Fusarium oxysporum f.sp. cubense) is an important disease in banana. Fusarium wilt was hard to control because the pathogen can survive in many kind of soils type although there is no host. Therefore, overcoming the disease is urgently needed such as biological control. The endophytic Bacillus of banana was begun to use as antagonist agent to the pathogen. This research aimed to study the mechanism of antagonism and physiological character of Bacillus. There were 27 Bacillus isolates examined in-vitro to test the production of IAA, HCN, chitinase, pectinase, and antagonism. The top ten isolates based on the test in vitro were used to test in planta. The research showed that Bacillus were able to produce IAA, HCN, chitinase, pectinase, and able to retard the growth of Foc colony. The application of isolat B25 on banana seedling could decrease the disease intensity but still unable to prevent the fusarium wilt infection.</p>

scholarly journals Isolation of Nonpathogenic Mutants of Fusarium oxysporum f. sp. melonis for Biological Control of Fusarium Wilt in Cucurbits

2002 ◽  
Vol 92 (2) ◽  
pp. 164-168 ◽  
Author(s):  
Stanley Freeman ◽  
Aida Zveibil ◽  
Haim Vintal ◽  
Marcel Maymon
Keyword(s):  
Biological Control ◽  
Fusarium Oxysporum ◽  
Fungal Pathogens ◽  
Conidial Suspension ◽  
Wild Type ◽  
Seedling Mortality ◽  
Type Isolate ◽  
Novel Approach ◽  
Mutant Strains ◽  
Race 2

Two nonpathogenic mutant strains 4/4 and 15/15 of Fusarium oxysporum f. sp. melonis (race 1,2) were isolated by a continuous dipinoculation technique following UV mutagenesis of the virulent wild-type isolate FOM1.2. No disease symptoms or detrimental effects were observed following inoculation of muskmelon seedlings by strain 4/4. In contrast, strain 15/15 caused mortality of susceptible cultivars although to a lesser extent than the wild-type isolate. Strain 4/4 colonized a variety of muskmelon and watermelon cultivars. In muskmelon cv. Ein Dor, seedlings were dipped in a conidial suspension of strain 4/4 and planted in medium amended with the mutant to achieve 100% colonization of roots and between 30 to 70% of the lower stem tissues 7 days after planting. Similar percent colonization of watermelon seedlings by strain 4/4 was recorded. In cross-protection experiments with muskmelon cultivars, significant reduction in seedling mortality was observed between 4/4-colonized FOM1.2. challenged plants compared with that of wild-type challenged plants alone. Similarly, strain 4/4 was able to significantly reduce mortality of watermelon seedlings caused by F. oxysporum f. sp. niveum race 2. This novel approach of generating nonpathogenic mutants for biological control in Fusarium spp. and other fungal pathogens from virulent wild-type isolates may be beneficial for control, because the mutant strains, lacking only in pathogenicity, may compete more efficiently than other biocontrol organisms against the pathogen of origin.

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