Effects of Triazole and Strobilurin-Based Fungicides on Fusarium culmorum on Wheat

Fusarium culmorum is an important pathogen, that causes pre and post-emergence death in seedlings from both seed and soil-borne sources, in addition to causing root, crown root and wheat head infections on wheat. Treatment of seeds with fungicides is especially important to inhibit seed originated seedling infections when cultural methods are ineffective against the infection of the pathogen in root and crown root and the lack of completely resistant wheat cultivars against this pathogen. The efficiency of fungicides with prothioconazole + tebuconazole and triticonazole + pyraclostrobin active ingredients, licensed on Fusarium spp. in seeds, on seed originated seedling infections of F. culmorum is determined in vitro and in vivo conditions. Seeds of Flamura-85 bread wheat cultivar, naturally infected with F. culmorum S-14, were used in this study. The effect of treating seeds naturally infected with F. culmorum S-14 with fungicides on seed germination, root length, coleoptile length and disease severity was determined in the experiment in vitro. Germination rate of the seed was determined as 68% for triticonazole + pyraclostrobin and 43% for prothioconazole + tebuconazole, while disease severity was 42.70% and 61.30%, respectively. While both fungicides were determined to be effective on the disease severity, the effect of triticonazole + pyraclostrobin on disease severity was found to be higher than prothioconazole + tebuconazole. Because of the higher rate of effectiveness of triticonazole + pyraclostrobin to prevent seed-borne infections in vitro conditions, it was determined that the fungicide causes an increase in germination rate with wet and dry weight of the seed, while significantly decreasing the disease severity, in the tests to determine the effectiveness of the fungicide in vivo conditions.

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Improving the Biocontrol Potential of Bacterial Antagonists with Salicylic Acid against Brown Rot Disease and Impact on Nectarine Fruits Quality

Agronomy ◽

10.3390/agronomy11020209 ◽

2021 ◽

Vol 11 (2) ◽

pp. 209

Author(s):

Nadia Lyousfi ◽

Rachid Lahlali ◽

Chaimaa Letrib ◽

Zineb Belabess ◽

Rachida Ouaabou ◽

...

Keyword(s):

Salicylic Acid ◽

Disease Severity ◽

Mycelial Growth ◽

Brown Rot ◽

Antagonistic Bacteria ◽

Biological Treatments ◽

Rot Disease ◽

The Impact

The main objective of this study was to evaluate the ability of both antagonistic bacteria Bacillus amyloliquefaciens (SF14) and Alcaligenes faecalis (ACBC1) used in combination with salicylic acid (SA) to effectively control brown rot disease caused by Monilinia fructigena. Four concentrations of salicylic acid (0.5%, 2%, 3.5%, and 5%) were tested under in vitro and in vivo conditions. Furthermore, the impact of biological treatments on nectarine fruit parameters’ quality, in particular, weight loss, titratable acidity, and soluble solids content, was evaluated. Regardless of the bacterium, the results indicated that all combined treatments displayed a strong inhibitory effect on the mycelial growth of M. fructigena and disease severity. Interestingly, all SA concentrations significantly improved the biocontrol activity of each antagonist. The mycelial growth inhibition rate ranged from 9.79% to 88.02% with the highest reduction rate recorded for bacterial antagonists in combination with SA at both concentrations of 0.5% and 3.5%. The in vivo results confirmed the in vitro results with a disease severity varying from 0.00% to 51.91%. A significant biocontrol improvement was obtained with both antagonistic bacteria when used in combination with SA at concentrations of 0.5% and 2%. The lowest disease severity observed with ACBC1 compared with SF14 is likely due to a rapid adaptation and increase of antagonistic bacteria population in wounded sites. The impact of all biological treatments revealed moderate significant changes in the fruit quality parameters with weight loss for several treatments. These results suggest that the improved disease control of both antagonistic bacteria was more likely directly linked to both the inhibitory effects of SA on pathogen growth and induced fruit resistance.

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Control of lettuce bottom rot by isolates of Trichoderma spp

Summa Phytopathologica ◽

10.1590/0100-5405/1968 ◽

2014 ◽

Vol 40 (2) ◽

pp. 141-146 ◽

Cited By ~ 4

Author(s):

Zayame Vegette Pinto ◽

Matheus Aparecido Pereira Cipriano ◽

Amaury da Silva dos Santos ◽

Ludwig Heinrich Pfenning ◽

Flávia Rodrigues Alves Patrício

Keyword(s):

Mycelial Growth ◽

High Capacity ◽

Dry Weight ◽

Second Step ◽

Trichoderma Spp ◽

In Vivo Experiments ◽

Bottom Rot ◽

Trichoderma Isolates

Bottom rot, caused by Rhizoctonia solani AG 1-IB, is an important disease affecting lettuce in Brazil, where its biological control with Trichoderma was not developed yet. The present study was carried out with the aim of selecting Trichoderma isolates to be used in the control of lettuce bottom rot. Forty-six Trichoderma isolates, obtained with baits containing mycelia of the pathogen, were evaluated in experiments carried out in vitro and in vivo in a greenhouse in two steps. In the laboratory, the isolates were evaluated for their capabilities of parasitizing and producing toxic metabolic substances that could inhibit the pathogen mycelial growth. In the first step of the in vivo experiments, the number and the dry weight of lettuce seedlings of the cultivar White Boston were evaluated. In the second step, 12 isolates that were efficient in the first step and showed rapid growth and abundant sporulation in the laboratory were tested for their capability of controlling bottom rot in two repeated experiments, and had their species identified. The majority of the isolates of Trichoderma spp. (76%) showed high capacity for parasitism and 50% of them produced toxic metabolites capable of inhibiting 60-100% of R. solani AG1-IB mycelial growth. Twenty-four isolates increased the number and 23 isolates increased the dry weight of lettuce seedlings inoculated with the pathogen in the first step of the in vivo experiments.In both experiments of the second step, two isolates of T. virens, IBLF 04 and IBLF 50, reduced the severity of bottom rot and increased the number and the dry weight of lettuce seedlings inoculated with R. solani AG1-IB. These isolates had shown a high capacity for parasitism and production of toxic metabolic substances, indicating that the in vitro and in vivo steps employed in the present study were efficient in selecting antagonists to be used for the control of lettuce bottom rot.

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The Rhodococcus opacus PD630 Heparin-Binding Hemagglutinin Homolog TadA Mediates Lipid Body Formation

Applied and Environmental Microbiology ◽

10.1128/aem.00985-10 ◽

2010 ◽

Vol 76 (21) ◽

pp. 7217-7225 ◽

Cited By ~ 36

Author(s):

Daniel P. MacEachran ◽

M. E. Prophete ◽

A. J. Sinskey

Keyword(s):

Kinetic Studies ◽

Lipid Body ◽

Dry Weight ◽

Rhodococcus Opacus ◽

Lipid Bodies ◽

Heparin Binding ◽

Tag Biosynthesis ◽

Tag Accumulation

ABSTRACT Generally, prokaryotes store carbon as polyhydroxyalkanoate, starch, or glycogen. The Gram-positive actinomycete Rhodococcus opacus strain PD630 is noteworthy in that it stores carbon in the form of triacylglycerol (TAG). Several studies have demonstrated that R. opacus PD630 can accumulate up to 76% of its cell dry weight as TAG when grown under nitrogen-limiting conditions. While this process is well studied, the underlying molecular and biochemical mechanisms leading to TAG biosynthesis and subsequent storage are poorly understood. We designed a high-throughput genetic screening to identify genes and their products required for TAG biosynthesis and storage in R. opacus PD630. We identified a gene predicted to encode a putative heparin-binding hemagglutinin homolog, which we have termed tadA (triacylglycerol accumulation deficient), as being important for TAG accumulation. Kinetic studies of TAG accumulation in both the wild-type (WT) and mutant strains demonstrated that the tadA mutant accumulates 30 to 40% less TAG than the parental strain (WT). We observed that lipid bodies formed by the mutant strain were of a different size and shape than those of the WT. Characterization of TadA demonstrated that the protein is capable of binding heparin and of agglutinating purified lipid bodies. Finally, we observed that the TadA protein localizes to lipid bodies in R. opacus PD630 both in vivo and in vitro. Based on these data, we hypothesize that the TadA protein acts to aggregate small lipid bodies, found in cells during early stages of lipid storage, into larger lipid bodies and thus plays a key role in lipid body maturation in R. opacus PD630.

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Extraction Optimization of Polysaccharides From Corn Silk and Their Antioxidant Activities in vitro and in vivo

Frontiers in Pharmacology ◽

10.3389/fphar.2021.738150 ◽

2021 ◽

Vol 12 ◽

Author(s):

Liang Zhang ◽

Yang Yang ◽

Zhanyong Wang

Keyword(s):

Antioxidant Activities ◽

Dry Weight ◽

Extraction Time ◽

Solid Ratio ◽

Corn Silk ◽

Response Surface Technique ◽

Experimental Yield ◽

Temperature Liquid

Response surface technique was employed for improving the extraction of corn silk polysaccharides (CSP). Temperature, liquid-to-solid ratio, and per extraction time were all examined as separate factors. The optimal extraction parameters were determined by fitting experimental data to a second-order polynomial; a liquid-to-solid ratio of 21.5 ml/g, temperature equivalent to 88°C, and extraction time of 1.87 h. The experimental yield of the extracted polysaccharides following the application of these conditions was 4.33 ± 0.08% (dry weight), which fit quite well with the predicted value. CSP’s strong scavenging capabilities against hydroxyls, 1,1-diphenyl-2-picrylhydrazyl radicals, and superoxide anions along with its excellent reducing potential, were demonstrated in an in vitro antioxidant experiment. Meanwhile, in vivo testing revealed that CSP substantially enhanced glutathione peroxidase and superoxide dismutase activities. The Malondialdehyde levels in the liver and serum of aged mice also underwent a decrease. This study found that CSP has a substantial antioxidant potential in vitro and in vivo, suggesting that it might be used as an antioxidant in food and medicine.

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ASAI KEMAMPUAN BAKTERI ENDOFIT DARI KACANG TANAH DALAM MENGHAMBAT PERTUMBUHAN Sclerotium sp. PADA KECAMBAH KACANG TANAH

JURNAL HAMA DAN PENYAKIT TUMBUHAN TROPIKA ◽

10.23960/j.hptt.214178-186 ◽

2020 ◽

Vol 14 (2) ◽

pp. 178-186

Author(s):

Lisa Novita Arios ◽

Dwi Suryanto . ◽

Kiki Nurtjahja . ◽

Erman Munir .

Keyword(s):

Endophytic Bacteria ◽

Culture Method ◽

Dry Weight ◽

Dual Culture ◽

Seedling Height ◽

Bacterial Isolates ◽

Peanut Seed ◽

Number Of Leaves

Assay on ability of endophytic bacteria isolated from peanut to inhibit Sclerotium sp. growth in peanut seedlings. A study on assay of ability of endophytic bacteria to inhibit Sclerotium sp. in peanut seedling has been done. The bacteria were isolated from peanut healthy plants, while Sclerotium sp. was isolated from infected peanaut plant. Antagonistic assay was conducted by dual culture method. In vivo assay of inhibiting Sclerotium sp. was conducted by dipping peanut seed in bacterial solution, and planting the seed in soil:compost (3:1) growing media. Six endophytic bacterial isolates showed to inhibit the growth of Sclerotium sp. in vitro. LN1 seemed to inhibit more of Sclerotium sp., while LN5 showed to inhibit less. Two potential isolates LN1 of gram-negative and LN2 of gram-positive using for further study showed to decrease more of dumping off. It also seemed that the isolates increased the seedling height, number of leaves, and dry weight.

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Adjustment of Mineral Elements in the Culture Medium for the Micropropagation of Three Vriesea Bromeliads from the Brazilian Atlantic Forest: The Importance of Calcium

HortScience ◽

10.21273/hortsci.44.1.106 ◽

2009 ◽

Vol 44 (1) ◽

pp. 106-112 ◽

Cited By ~ 15

Author(s):

Alice Noemí Aranda-Peres ◽

Lázaro Eustáquio Pereira Peres ◽

Edson Namita Higashi ◽

Adriana Pinheiro Martinelli

Keyword(s):

New Media ◽

Mineral Composition ◽

Culture Media ◽

Dry Weight ◽

Defined Medium ◽

Ms Medium ◽

Media Formulation ◽

Half Strength

Many different species of Bromeliaceae are endangered and their conservation requires specific knowledge of their growth habits and propagation. In vitro culture of bromeliads is an important method for efficient clonal propagation and in vitro seed germination can be used to maintain genetic variability. The present work aims to evaluate the in vitro growth and nutrient concentration in leaves of the epiphyte bromeliads Vriesea friburguensis Mez, Vriesea hieroglyphica (Carrière) E. Morren, and Vriesea unilateralis Mez, which exhibit slow rates of growth in vivo and in vitro. Initially, we compared the endogenous mineral composition of bromeliad plantlets grown in half-strength Murashige and Skoog (MS) medium and the mineral composition considered adequate in the literature. This approach suggested that calcium (Ca) is a critical nutrient and this was considered for new media formulation. Three new culture media were defined in which the main changes to half-strength MS medium were an increase in Ca, magnesium, sulfur, copper, and chloride and a decrease in iron, maintaining the nitrate:ammonium rate at ≈2:1. The main difference among the three new media formulated was Ca concentration, which varied from 1.5 mm in half-strength MS to 3.0, 6.0, and 12 mm in M2, M3, and M4 media, respectively. Consistently, all three species exhibited significantly higher fresh and dry weight on M4, the newly defined medium with the highest level of Ca (12 mm). Leaf nitrogen, potassium, zinc, magnesium, and boron concentrations increased as Ca concentration in the medium increased from 1.5 to 12 mm.

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Lab and Field Level Potential of Endophytic Bacteria in Managing the Dry Root Rot Disease in Black Gram Incited by Rhizoctonia bataticola (Taubenh) Butler

Legume Research - An International Journal ◽

10.18805/lr-4522 ◽

2021 ◽

Author(s):

N. Kiran Kumar ◽

P. Nagamani ◽

K. Viswanath ◽

L. Prasanthi

Keyword(s):

Root Rot ◽

Protease Activity ◽

Endophytic Bacteria ◽

Phosphate Solubilization ◽

Growth Promotion ◽

Dry Weight ◽

Black Gram ◽

Rhizoctonia Bataticola

Background: The plant growth promotion and efficacy against phytopathogens by the endophytic bacteria are being focused now due to their ecofriendly nature. Methods: Endophytic bacteria (24 nos) isolated from the roots, stems and leaves of black gram plants collected from different locations were tested for their potential to inhibit the growth of R. bataticola under in vitro and in vivo conditions. Result: The leaf endophyte BLE 4 exhibited maximum inhibition (79.6%) of R. bataticola followed by BSE 4 (77.4%), BSE 7 (77.0%) and BLE 1 (74.0%). Among these 4 isolates tested as seed treatment and soil application, there was significant increase in dry weight (7.1 g), plant height (37.7 cm), number of branches (13.2) and number of pods (26.2) in BLE 4 treated plots. Whereas, the incidence of dry root rot and yield were insignificant. In the screening study of isolates for their phosphate solubilization potential, protease activity, siderophore and HCN production, no single isolate possessed all the properties, but siderophore production, protease activity and phosphate solubilization were found in BSE 4, BRE 3, BRE 5 and BRE 10 isolates.

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Isolation and Identification of Fusarium spp., the Causal Agents of Onion (Allium cepa) Basal Rot in Northeastern Israel

Biology ◽

10.3390/biology9040069 ◽

2020 ◽

Vol 9 (4) ◽

pp. 69

Author(s):

Ben Kalman ◽

Dekel Abraham ◽

Shaul Graph ◽

Rafael Perl-Treves ◽

Yael Meller Harel ◽

...

Keyword(s):

Allium Cepa ◽

Fusarium Species ◽

Germination Rate ◽

Post Inoculation ◽

Fusarium Spp ◽

Isolation And Identification ◽

Preventive Program ◽

Onion Bulbs ◽

Basal Rot

Over the past decade, there have been accumulating reports from farmers and field extension personnel on the increasing incidence and spread of onion (Allium cepa) bulb basal rot in northern Israel. The disease is caused mainly by Fusarium species. Rotting onion bulbs were sampled from fields in the Golan Heights in northeastern Israel during the summers of 2017 and 2018. Tissue from the sampled onion bulbs was used for the isolation and identification of the infecting fungal species using colony and microscopic morphology characterization. Final confirmation of the pathogens was performed with PCR amplification and sequencing using fungi-specific and Fusarium species-specific primers. Four Fusarium spp. isolates were identified in onion bulbs samples collected from the contaminated field: F. proliferatum, F. oxysporum f. sp. cepae, and two species less familiar as causative agents of this disease, F. acutatum and F. anthophilium. Phylogenetic analysis revealed that these species subdivided into two populations, a northern group isolated from white (Riverside cv.) onion bulbs, and a southern group isolated from red (565/505 cv.) bulbs. Pathogenicity tests conducted with seedlings and bulbs under moist conditions proved that all species could cause the disease symptoms, but with different degrees of virulence. Inoculating seeds with spore suspensions of the four species, in vitro, significantly reduced seedlings’ germination rate, hypocotyl elongation, and fresh biomass. Mature onion bulbs infected with the fungal isolates produced typical rot symptoms 14 days post-inoculation, and the fungus from each infected bulb was re-isolated and identified to satisfy Koch’s postulates. The onion bulb assay also reflected the degree of sensitivity of different onion cultivars to the disease. This work is the first confirmed report of the direct and primary cause of Fusarium onion basal rot disease in northeastern Israel. These findings are a necessary step towards uncovering the mycoflora of the diseased onion plants and developing a preventive program that would reduce the disease damage.

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Yolk platelet degradation in preemergence Artemia embryos: response to protons in vivo and in vitro

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1987.252.4.r774 ◽

1987 ◽

Vol 252 (4) ◽

pp. R774-R781 ◽

Cited By ~ 1

Author(s):

P. J. Utterback ◽

S. C. Hand

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Dry Weight ◽

Platelet Protein ◽

Transmission Electron ◽

Structural Differences ◽

Alkaline Conditions ◽

Yolk Platelet

Alteration of intracellular pH (pHi) influences yolk platelet degradation during preemergence development in Artemia embryos. Cysts incubated for 10 h under conditions of aerobic development (aqueous medium equilibrated with 60% N2-40% O2, pHi greater than or equal to 7.9) exhibit a significant decrease in numbers of yolk platelets and platelet protein. In contrast, cysts incubated for 10 h under aerobic acidosis (60% CO2-40% O2, pHi = 6.8) show no significant decrease in numbers of yolk platelets or platelet protein. When subjected to alkaline conditions in vitro, yolk platelets release protein exponentially as a function of time. The process is essentially complete in 40 min. The extent of protein and lipid release from platelets increases markedly as pH of the medium is raised in increments from 6.3 to 8.0. Concomitant with these changes are reduction (50%) in platelet dry weight and reduction (21%) in platelet diameter. Transmission electron microscopy does not reveal major structural differences between isolated yolk platelets and those contained in hydrated embryos. The proton effects on platelet composition and size detected in vitro may explain in part the mechanism of platelet degradation observed during aerobic development and its suppression under conditions of acidic pHi.

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