scholarly journals Sensitivity of Colletotrichum acutatum Isolates to Selected Fungicides

2015 ◽  
Vol 63 (4) ◽  
pp. 1111-1119 ◽  
Author(s):  
Barbora Jílková ◽  
Jana Víchová ◽  
Radovan Pokorný ◽  
Karel Vejražka
Keyword(s):  
Active Ingredient ◽  
Host Plants ◽  
Germination Rate ◽  
Inhibitory Effect ◽  
Conidial Germination ◽  
Colletotrichum Acutatum ◽  
White Lupin ◽  
Active Ingredients ◽  
Mycelium Growth ◽  
Almost All

Laboratory tests of six isolates of the pathogen Colletotrichum acutatum from different host plants demonstrated the varying sensitivity of pathogen with regard to mycelium growth and conidial germination after treatment with seven fungicides containing various active ingredients. None of the evaluated isolates was tolerant to the selected active ingredients in the fungicides. In tests of mycelium growth sensitivity, isolates from lupin and strawberry were most frequently identified as the most sensitive of all evaluated fungicides. The safflower isolate, on the other hand, most frequently exhibited the lowest reaction to fungicides. Differences in conidial germination of individual isolates were not detected in fungicides with the active ingredients dithianon, folpet and mancozeb, for which inhibition reached 100% in almost all isolates. The most significant differences in sensitivity among individual isolates were recorded in fungicides with the active ingredients azoxystrobin and metiram. In the case of the fungicide with active ingredient azoxystrobin, the highest inhibitory effect was achieved in the safflower isolate and the lowest in the white lupin isolate. After treatment with the fungicide with active ingredient metiram, the lowest germination rate was recorded in isolates from safflower and strawberry and the highest in isolates from hypericum and lupin.

The Effect of High Concentrations of Ethylene on Seed Germination of Douglas Fir (Pseudotsugamenziesii (Mirb.) Franco)

1975 ◽  
Vol 5 (3) ◽  
pp. 419-423 ◽  
Author(s):  
Carey Borno ◽  
Iain E. P. Taylor
Keyword(s):  
Seed Germination ◽  
Germination Rate ◽  
Inhibitory Effect ◽  
Germination Percentage ◽  
Douglas Fir ◽  
Control Treatment ◽  
Continuous Exposure ◽  
Short Term ◽  
Short Term Exposure ◽  
High Concentrations

Stratified, imbibed Douglas fir (Pseudotsugamenziesii (Mirb.) Franco) seeds were exposed to 100% ethylene for times between 0 and 366 h. Germination rate and germination percentage were increased by treatments up to 48 h. The 12-h treatment gave largest stimulation; 30% enhancement of final germination percentage over control. Treatment for 96 h caused increased germination rate for the first 5 days but reduced the germination percentage. Germinants were subject to continuous exposure to atmospheres containing 0.1 – 200 000 ppm ethylene in air, but it did not stimulate growth, and the gas was inhibitory above 100 ppm. Although some effects of high concentrations of ethylene may have been due to the lowering of oxygen supplies, this alone was insufficient to account for the full inhibitory effect. The mechanism of stimulation by short-term exposure to ethylene is discussed.

A Quantitative Study of the Behaviour of the Male Mormoniella Vitripennis (Walker) (Hymenoptera, Pteromalidae) Towards Two Constant Stimulus-Situations

Behaviour ◽  
1961 ◽  
Vol 18 (4) ◽  
pp. 288-311 ◽  
Author(s):  
Robert Barrass
Keyword(s):  
Nervous Activity ◽  
Specific Effect ◽  
Inhibitory Effect ◽  
Constant Stimulus ◽  
Receptive Female ◽  
Short Term ◽  
Excitatory Effect ◽  
Time Intervals ◽  
Almost All ◽  
Term Response

Abstract1. The method of dual quantification was used to study the effect of courtship of both receptive and non-receptive females on the subsequent behaviour of the male Mormoniella vitripennis. 2. The male's responsiveness to successive non-receptive females waned when the time between presentations was short. The extent of this waning was less with longer time intervals. 3. When many females were presented to a male one after another the male courted almost all of them if they were receptive females but only a few if they were non-receptive females. 4. A single courtship of either a receptive or a non-receptive female had a similar effect on the male's subsequent behaviour and recovery occurred in a similar way. 5. Courtship of 20 non-receptive females reduced the male's response to further females more than did courtship of 20 receptive females. 6. The significance of these observations is discussed with reference to the use of dummy animals and to the recent ethological concepts of reaction specific energy, motivational impulses, specific action potentiality and consummatory act. 7. An endogenous central nervous influence on the male's readiness to respond is postulated. Courtship has a short-term response-specific effect (receptive or non-receptive females) and an inhibitory stimulus-specific effect (non-receptive females). With receptive females the inhibitory effect is absent and/or mating has an excitatory effect. The stimuli provided by a receptive female must direct nervous activity rather than release a limited amount of stored energy.

scholarly journals Effect of three composts with active ingredients of Pseudomonas fluorescens on the development of white root disease and production of rubber plants

2021 ◽  
Vol 22 (8) ◽  
Author(s):  
NURHAYATI DAMIRI ◽  
RIZAL ROFIQI ◽  
MULAWARMAN MULAWARMAN ◽  
SUPLI E. RAHIM ◽  
TRI RAPANI FEBYANTI
Keyword(s):  
Pseudomonas Fluorescens ◽  
Active Ingredient ◽  
Root Disease ◽  
Biological Agent ◽  
The Other ◽  
Active Ingredients ◽  
Severe Infections ◽  
Rigidoporus Lignosus ◽  
The Impact ◽  
Latex Production

Abstract. Damiri N, Rofiqi R, Mulawarnam, Rahim SE, Febyanti TP. 2021. Effect of three composts with active ingredients of Pseudomonas fluorescens on the development of white root disease and production of rubber plants. Biodiversitas 22: 3237-3242. White root disease (WRD) caused by Rigidoporus lignosus is a very dangerous disease and a scourge for rubber farmers because it can result in decreased production and kill rubber plants. This research was conducted to observe the impact of compost enriched with the biological agent Pseudomonas fluorescens on the development of white root disease and production in rubber plants. The results showed that the application of compost with active ingredient of P. fluorescens isolates A and B reduced the severity of white root disease in plants with mild, moderate and severe infections, 34.12%, 29.31% and 57.21% respectively. Application of compost with P. fluorescens isolates A and B, either singly or in combination, can increase latex production. The treatment of giving compost enriched with P. fluorescens isolates AR and ABR on rubber plants infected with mild WRD resulted in the highest latex production of 406 gm and 402.74 gm per plant, respectively. These two treatments did not differ from each other but were significantly different from the other treatments and controls.

scholarly journals Subcellular location and properties of bactericidal factors from human neutrophils.

1986 ◽  
Vol 164 (5) ◽  
pp. 1407-1421 ◽  
Author(s):  
J E Gabay ◽  
J M Heiple ◽  
Z A Cohn ◽  
C F Nathan
Keyword(s):  
Protein S ◽  
Subcellular Location ◽  
Inhibitory Effect ◽  
Human Neutrophils ◽  
E Coli ◽  
Fractionation Scheme ◽  
Percoll Gradients ◽  
Nonionic Detergent ◽  
Almost All ◽  
Triton X

We examined the subcellular location of bactericidal factors (BF) in human neutrophils, using an efficient fractionation scheme. Nitrogen bomb cavitates of DIFP-treated PMN were centrifuged through discontinuous Percoll gradients, each fraction extracted with 0.05 M glycine, pH 2.0, and tested for the killing of Escherichia coli. greater than 90% of BF coisolated with the azurophil granules. After lysis of azurophils, 98% of azurophil-derived BF (ADBF) sedimented with the membrane. ADBF activity was solubilized from azurophil membrane with either acid or nonionic detergent (Triton X-100, Triton X-114). Bactericidal activity was linear with respect to protein concentration over the range 0.3-30 micrograms/ml. 0.1-0.3 microgram/ml ADBF killed 10(5) E. coli within 30 min at 37 degrees C. At 1.4 micrograms/ml, 50% of 2 X 10(5) bacteria were killed within 5 min. ADBF was effective between pH 5-8, with peak activity at pH 5.5. Glucose (20 mM), EDTA (1-25 mM), and physiologic concentrations of NaCl or KCl had little or no inhibitory effect on ADBF. ADBF killed both Gram-positive and Gram-negative virulent clinical isolates, including listeria, staphylococci, beta-hemolytic streptococci, and Pseudomonas aeruginosa. Thus, under these conditions of cell disruption, fractionation, extraction, and assay, almost all BF in human PMN appeared to be localized to the membrane of azurophilic granules as a highly potent, broad-spectrum, rapidly acting protein(s) effective in physiologic medium. Some of these properties appear to distinguish ADBF from previously described PMN bactericidal proteins.

Mating-type genes control sexual reproduction, conidial germination and virulence in Cochliobolus lunatus

2021 ◽  
Author(s):  
Kexin Liu ◽  
Jiaqi Jia ◽  
Nan Chen ◽  
Dandan Fu ◽  
Jiaying Sun ◽  
...  
Keyword(s):  
Mating Type ◽  
Pathogenic Fungus ◽  
Germination Rate ◽  
Dry Weight ◽  
Single Copy ◽  
Conidial Germination ◽  
Curvularia Lunata ◽  
Wild Type ◽  
Cochliobolus Lunatus ◽  
Mat Genes

Cochliobolus lunatus (anamorph: Curvularia lunata) is a major pathogenic fungus that causes the Curvularia leaf spot of maize. ClMAT1-1-1 and ClMAT1-2-1, the C. lunatus orthologs of Cochliobolus heterostrophus ChMAT1-1-1 and ChMAT1-2-1, were investigated in the present study to uncover their functions in C. lunatus. Southern blot analysis showed that these mating-type MAT genes exist in the C. lunatus genome as a single copy. ClMAT1-1-1 and ClMAT1-2-1 were knocked out and complemented to generate ΔClmat1-1-1 and ΔClmat1-2-1, ΔClmat1-1-1-C and ΔClmat1-2-1-C, respectively. The mutant strains had defective sexual development and failed to produce pseudothecia. There were no significant differences in growth rate or conidia production between the mutant and wild-type strains. However, the aerial mycelia and mycelial dry weight of ΔClmat1-1-1 and ΔClmat1-2-1 were lower than that of wild type, suggesting that MAT genes affect asexual development. ClMAT genes were involved in the responses to cell wall integrity and osmotic adaptation. ΔClmat1-2-1 had a lower conidial germination rate than the wild-type strain CX-3. The virulence of ΔClmat1-2-1 and ΔClmat1-1-1 was also reduced compared to the wild type. Complementary strains could restore all the phenotypes.

The effect of Wogonoside on the expression of pulmonary fibrosis factor in Mycoplasma pneumoniae pneumonia

2020 ◽  
Author(s):  
Huihui Wang ◽  
Xiaoxi Wang ◽  
Zhimin Yang ◽  
Huixing Xu ◽  
Xin Wang ◽  
...  
Keyword(s):  
Mycoplasma Pneumoniae ◽  
Active Ingredient ◽  
A549 Cells ◽  
Scutellaria Baicalensis ◽  
Chinese Herbs ◽  
Affinity Constant ◽  
Active Ingredients ◽  
Pulmonary Interstitial Fibrosis ◽  
Mycoplasma Pneumoniae Pneumonia ◽  
Tof Ms

Abstract BACKGROUND Mycoplasma pneumoniae pneumonia (MPP) is an acute respiratory infectious pneumonia with pulmonary interstitial fibrosis. TGF-β1 is well accepted as the central mediator for fibrosis which promotes the formation of tissue fibrosis factor. Qinbaiqingfei pellet (Qinbai) has already been approved as the first effective new traditional Chinese medicine which can delay activities of Mycoplasma pneumoniae (M.pneumoniae) and protect lung epithelial cells in clinical trials. However, the mechanism of Qinbai inhibiting the expression of TGF-β1 is still unclear. METHODS The Chinese herbs in Qinbai were screened by surface plasmon resonance (SPR) and it was deteimined that Scutellaria baicalensis extracts in Qinbai showed the best binding with TGF-β1. Then the active ingredient whicn can be bound with TGF-β1 protein in the solution of Qinbai and Scutellaria baicalensis was isolated and analyzed by UPLC-Q-TOF-MS, which proved the active ingredient was Wogonoside. The affinity constant of Wogonoside and TGF-β1 protein was measured by SPR affinity analysis. A549 cells infected with M.pneumoniae were intervened by Wogonoside, and then the expression of TGF-β1 and Smad3 in A549 cells were analyzed by PCR and western blotting. RESULTS The results showed the bound effect of Scutellaria baicalensis and TGF-β1 was effective. The active ingredients which can be bound with TGF-β1 in the solution of Scutellaria baicalensis and Qinbai were obtained and analyzed to investigate the mechanism of Qinbai inhibiting the expression of TGF-β1. UPLC-Q-TOF-MS results showed that the active ingredients was Wogonoside. SPR affinity analysis showed that the affinity constant was 21.71 µM. Pharmacological experiments revealed that Wogonoside strongly inhibited the expression of TGF-β1 and Smad3 in A549 cells infected by M.pneumoniae. CONCLUSION Wogonoside in Qinbai can be bound with TGF-β1 and down-regulate the expression of lung fibrosis factors TGF-β1 and Smad3. The finding may improve our understanding the molecular mechanism of Qinbai mediating MPP and provide new sights into the future pharmacological investigation of Qinbai.

scholarly journals Resistance to Benzimidazole and Dicarboximide Fungicides in Greenhouse Isolates of Botrytis cinerea

Plant Disease ◽  
1999 ◽  
Vol 83 (6) ◽  
pp. 569-575 ◽  
Author(s):  
L. F. Yourman ◽  
S. N. Jeffers
Keyword(s):  
South Carolina ◽  
Botrytis Cinerea ◽  
Active Ingredient ◽  
Disease Incidence ◽  
Correlation Coefficients ◽  
Effective Concentration ◽  
Mycelium Growth ◽  
Thiophanate Methyl ◽  
Conidium Germination ◽  
The Mean

In 1996 and 1997, 325 isolates of Botrytis cinerea were collected from 35 commercial greenhouses growing ornamental crops in South Carolina to determine the incidence of resistance to benzimidazole and dicarboximide fungicides. Conidium germination was assessed on a defined agar medium amended with either thiophanate-methyl (a benzimidazole) or vinclozolin (a di-carboximide). A total of 53 representative isolates were evaluated further for conidium germination and mycelium growth on fungicide-amended medium and for infection of geranium seedlings treated with thiophanate-methyl or vinclozolin at label rates. Isolates were considered sensitive to thiophanate-methyl or vinclozolin when the effective concentration of the fungicide active ingredient resulting in 50% inhibition of germination (EC50-germ) was ≤5 μg/ml or when the effective concentration of fungicide active ingredient resulting in 50% inhibition of mycelium growth (EC50-growth) was ≤1 μg/ml. Of all isolates, 81% (262/325) were resistant to thiophanate-methyl and 69% (223/325) were resistant to vinclozolin. Four phenotypes were observed: sensitive to both fungicides (17%), resistant to both fungicides (67%), resistant only to thiophanate-methyl (14%), and resistant only to vinclozolin (2%). Isolates resistant to at least one fungicide were found in 33 of the 35 locations from which samples were taken. Disease incidences on geranium seedlings treated with 600 μg/ml of thiophanate-methyl and then inoculated with isolates sensitive and resistant to this fungicide were 1.4 and 96.1%, respectively. Disease incidences on geranium seedlings treated with 600 μg/ml of vinclozolin and then inoculated with isolates sensitive and resistant to this fungicide were 0.3 and 91.9%, respectively. With thiophanate-methyl, correlation coefficients (r) between disease incidence and log EC50-germ or log EC50-growth were 0.987 and 0.992, respectively. With vinclozolin, correlation coefficients between disease incidence and log EC50-germ and log EC50-growth were 0.975 and 0.893, respectively. Correlation coefficients between the two EC50 values for thiophanate-methyl were 0.989 and for vinclozolin were 0.900. Isolates sensitive to thiophanate-methyl had a mean EC50-germ value of 0.93 μg/ml and a EC50-growth value of 0.11 μg/ml. For isolates sensitive to vinclozolin the mean EC50-germ value was 1.63 μg/ml and the mean EC50-growth value was 0.26 μg/ml. Thiophanate-methyl-resistant isolates had mean EC50-germ and EC50-growth values greater than 500 μg/ml while vinclozolin-resistant isolates had a mean EC50-germ value greater than 500 μg/ml and a mean EC50-growth value of 3.18 μg/ml.

scholarly journals Investigation on the Enzymatic Profile of Mulberry Alkaloids by Enzymatic Study and Molecular Docking

Molecules ◽  
2019 ◽  
Vol 24 (9) ◽  
pp. 1776 ◽  
Author(s):  
Zhihua Liu ◽  
Ying Yang ◽  
Wujun Dong ◽  
Quan Liu ◽  
Renyun Wang ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Type 2 Diabetes ◽  
Type 2 Diabetes Mellitus ◽  
Molecular Docking ◽  
Side Effects ◽  
Inhibitory Effect ◽  
Active Ingredients ◽  
Wide Range ◽  
Consensus Score

α-glucosidase inhibitors (AGIs) have been an important category of oral antidiabetic drugs being widely exploited for the effective management of type 2 diabetes mellitus. However, the marketed AGIs not only inhibited the disaccharidases, but also exhibited an excessive inhibitory effect on α-amylase, resulting in undesirable gastrointestinal side effects. Compared to these agents, Ramulus Mori alkaloids (SZ-A), was a group of effective alkaloids from natural Morus alba L., and showed excellent hypoglycemic effect and fewer side effects in the Phase II/III clinical trials. Thus, this paper aims to investigate the selective inhibitory effect and mechanism of SZ-A and its major active ingredients (1-DNJ, FA and DAB) on different α-glucosidases (α-amylase and disaccharidases) by using a combination of kinetic analysis and molecular docking approaches. From the results, SZ-A displayed a strong inhibitory effect on maltase and sucrase with an IC50 of 0.06 μg/mL and 0.03 μg/mL, respectively, which was similar to the positive control of acarbose with an IC50 of 0.07 μg/mL and 0.68 μg/mL. With regard to α-amylase, SZ-A exhibited no inhibitory activity at 100 μg/mL, while acarbose showed an obvious inhibitory effect with an IC50 of 1.74 μg/mL. The above analysis demonstrated that SZ-A could selectively inhibit disaccharidase to reduce hyperglycemia with a reversible competitive inhibition, which was primarily attributed to the three major active ingredients of SZ-A, especially 1-DNJ molecule. In the light of these findings, molecular docking study was utilized to analyze their inhibition mechanisms at molecular level. It pointed out that acarbose with a four-ring structure could perform desirable interactions with various α-glucosidases, while the three active ingredients of SZ-A, belonging to monocyclic compounds, had a high affinity to the active site of disaccharidases through forming a wide range of hydrogen bonds, whose affinity and consensus score with α-amylase was significantly lower than that of acarbose. Our study illustrates the selective inhibition mechanism of SZ-A on α-glucosidase for the first time, which is of great importance for the treatment of type 2 diabetes mellitus.

scholarly journals Microbial Decontamination of Onion by Corona Discharge Air Plasma during Cold Storage

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Eun Ha Chang ◽  
Yeoung Seuk Bae ◽  
Il Sheob Shin ◽  
Hyun Jin Choi ◽  
Ji Hyun Lee ◽  
...  
Keyword(s):  
Corona Discharge ◽  
Cold Storage ◽  
Mycelial Growth ◽  
Fungal Pathogens ◽  
Antimicrobial Agents ◽  
Treatment Time ◽  
Inhibitory Effect ◽  
Active Species ◽  
Conidial Germination ◽  
Air Plasma

Corona discharge air plasma (CDAP) is a nonthermal decontamination technology which is generating antimicrobial agents such as photons, electrons, positively and negatively charged ions, atoms, and free radicals. We investigated the effect of a corona discharge under atmospheric pressure on the sterilization of postharvest fungal pathogens on onion. The main antimicrobial reactive substance generated by CDAP was O3. The active species such as nitric oxide (NO) and nitric dioxide (NO2) were nearly detected in this experiment. CDAP treatment revealed different isolation frequencies depending on postharvest pathogens from diseased onions, showing less isolation frequency of Fusarium spp. and Alternaria sp. than that of Botrytis spp. when compared with untreatment onions during 10-month cold storage. CDAP treatment at 2∼2.6 ppm of O3 slightly stimulated the mycelial growth of Alternaria sp., while the treatment at 20∼24 ppm of O3 gradually inhibited mycelial growth by treatment time. However, Botrytis sp. showed different patterns of mycelial growth with CDAP treatment. Less than 4 hours’ treatment of CDAP slightly inhibited the mycelial growth of Botrytis sp., while 8 hours’ treatment of CDAP slightly stimulated the mycelial growth of Botrytis sp. not depending on the concentration of O3. The inhibitory effect of CDAP on the conidial germination of Alternaria sp. and Botrytis sp. was examined with treatment time and intensity of CDAP. The conidial germination of Alternaria sp. treated with CDAP at the concentration of 13.7∼14.4 ppm of O3 was strongly inhibited by time, showing y = 2.66x2 − 85.139x + 4.88 and R2 = 0.98. When the conidia of Alternaria sp. were exposed for 2 hours with varying plasma O3 concentration, the conidial germination was strongly inhibited as the concentration of O3 increases, showing y = −0.09x2 + 6.905x − 0.764 and R2 = 0.95. The conidia of Botrytis sp. also showed similar patterns to CDAP. The inhibitory effect of CDAP on the germination of postharvest pathogens depends on treatment time and O3 concentration.

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