scholarly journals Study of the Control of Fungus Occurring in Schizolobium amazonicum Seeds with the Use of Pyroligneous Extract

2020 ◽  
pp. 1-9
Author(s):  
D. G. Da C. Macedo ◽  
G. Q. David ◽  
O. M. Yamashita ◽  
W. M. Peres ◽  
M. A. C. de Carvalho ◽  
...  
Keyword(s):  
Plant Pathogens ◽  
Seed Quality ◽  
Fungal Growth ◽  
Phytopathogenic Fungi ◽  
Distilled Water ◽  
Seed Deterioration ◽  
Storage Fungi ◽  
Fusarium Sp ◽  
Petri Dishes ◽  
Production Losses

Fungi are the main microorganisms present in seeds, constituting the main cause of deterioration and production losses. Among the health testing methodologies for detecting fungi in seeds, incubation tests under controlled conditions facilitate fungal growth and sporulation. Therefore, this work aimed to evaluate the efficiency of pyroligneous extract in the control of phytopathogenic fungi occurring in Schizolobium amazonicum seeds. Treatments consisted of exposure of seeds to pyroligneous extract for a period of five minutes at concentrations (0%, 1%, 2.5%, 5%, 7%, 10% and 12.5%). The treated seeds were placed in Petri dishes, lined with two sheets of filter paper, moistened with sterile distilled water. The experimental design was completely randomized, consisting of 7 treatments, with 9 seeds per plate and 10 replications per treatment, totaling 630 seeds arranged in 7 Petri dishes. The evaluation was performed 8 days later, with the aid of stereoscopic and light microscopy, where the fungal growth in each seed in the plates was verified for the incidence calculation and then the identification of these. Pyroligneous extract was found to be efficient in reducing the fungal incidence of the genera Fusarium sp. and Rhizoctonia sp., fungi considered important plant pathogens that could compromise seed quality and seedling establishment in the field. It also reduced the incidence of storage fungi capable of causing seed deterioration and consequent loss of vigor, such as Aspergillus spp. occurring in seed samples of S. amazonicum. However, Penicillium sp was not controlled by treatment of S. amazonicum seeds with pyroligneous extract up to 12.5% concentration.

scholarly journals Double Gamers—Can Modified Natural Regulators of Higher Plants Act as Antagonists against Phytopathogens? The Case of Jasmonic Acid Derivatives

2020 ◽  
Vol 21 (22) ◽  
pp. 8681
Author(s):  
Nicolò Orsoni ◽  
Francesca Degola ◽  
Luca Nerva ◽  
Franco Bisceglie ◽  
Giorgio Spadola ◽  
...  
Keyword(s):  
Jasmonic Acid ◽  
Plant Pathogens ◽  
Higher Plants ◽  
Fungal Growth ◽  
Pathogenic Fungi ◽  
Inhibitory Effect ◽  
Fungal Species ◽  
Phytopathogenic Fungi ◽  
Phaeomoniella Chlamydospora ◽  
Horticultural Crops

As key players in biotic stress response of plants, jasmonic acid (JA) and its derivatives cover a specific and prominent role in pathogens-mediated signaling and hence are promising candidates for a sustainable management of phytopathogenic fungi. Recently, JA directed antimicrobial effects on plant pathogens has been suggested, supporting the theory of oxylipins as double gamers in plant-pathogen interaction. Based on these premises, six derivatives (dihydrojasmone and cis-jasmone, two thiosemicarbazonic derivatives and their corresponding complexes with copper) have been evaluated against 13 fungal species affecting various economically important herbaceous and woody crops, such as cereals, grapes and horticultural crops: Phaeoacremonium minimum, Neofusicoccum parvum, Phaeomoniella chlamydospora, Fomitiporia mediterranea, Fusarium poae, F. culmorum, F. graminearum, F. oxysporum f. sp. lactucae,F. sporotrichioides, Aspergillus flavus, Rhizoctonia solani,Sclerotinia spp. and Verticillium dahliae. The biological activity of these compounds was assessed in terms of growth inhibition and, for the two mycotoxigenic species A. flavus and F. sporotrichioides, also in terms of toxin containment. As expected, the inhibitory effect of molecules greatly varied amongst both genera and species; cis-jasmone thiosemicarbazone in particular has shown the wider range of effectiveness. However, our results show that thiosemicarbazones derivatives are more effective than the parent ketones in limiting fungal growth and mycotoxins production, supporting possible applications for the control of pathogenic fungi.

scholarly journals Prevalence and Occurrence of Various Wilt Pathogens Associated with Tomato (Solanum lycopersicum L.) in Togo

2019 ◽  
pp. 1-9
Author(s):  
Kwasi Dzola Ayisah ◽  
Koffi Simiti ◽  
Mawuli Kossivi Aziadekey
Keyword(s):  
Solanum Lycopersicum ◽  
Phytopathogenic Fungi ◽  
Incidence Rates ◽  
Soil Samples ◽  
Distilled Water ◽  
Tomato Plants ◽  
Solanum Lycopersicum L ◽  
Infected Tomato ◽  
Petri Dishes ◽  
Das Elisa

In December 2015, wilt symptoms on tomato plants (Solanum lycopersicum L.) were observed on vegetable growing perimeters in Sotouboua district in Togo. The disease, manifested by wilting of the youngest leaves followed by wilting and total desiccation of plants who eventually dy, leading to losses of up to 100%, is similar to bacterial wilt. The aim of this study, was to determine the pathogen responsible for the observed symptoms. For this purpose, phytosanitary surveys were carried out on tomato plots in Sotouboua distric, in 2018. During the surveys, Tomato plants infected by wilt and the plots soil samples, were collected on CECODRI project and farmers’ plots in the district. Soil samples were analyzed for the detection of nematodes while, tomato leaves, stems and roots were directly observed under binocular loupe and after incubation in Petri dishes containing filter paper moistened with distilled water to encourage sporulation of phytopathogenic fungi. Infected tomato stems and roots were analyzed by stem-streaming and DAS-ELISA tests using Agdia inc. Ralstonia solanacearum Patho Screen Kit to detect R. solanacearum. The results of the phytosanitary surveys showed that the wilt prevalence was 100% in Sotouboua district with incidence rates of up to 100%. Analysis of diseased samples, using stem-streaming and DAS-ELISA tests, revealed that 85.11% of diseased plants were infected by R. solanacearum. No nematodes were identified in the roots of the infected plants, but in soil samples only a few nematodes were counted. No fungus was found in the plants with wilt symptoms. It appears, therefore that, the wilt on tomato plants in Sotouboua district was caused by R. solanacearum. This, in our knowledge, is the first report on R. solanacearum infection on tomato in Togo.

scholarly journals A Protein from the Mold Aspergillus giganteus Is a Potent Inhibitor of Fungal Plant Pathogens

2001 ◽  
Vol 14 (11) ◽  
pp. 1327-1331 ◽  
Author(s):  
L. Vila ◽  
V. Lacadena ◽  
P. Fontanet ◽  
A. Martinez del Pozo ◽  
B. San Segundo
Keyword(s):  
Fungal Pathogens ◽  
Plant Pathogens ◽  
Magnaporthe Grisea ◽  
Crop Protection ◽  
Fungal Growth ◽  
Phytopathogenic Fungi ◽  
Antifungal Protein ◽  
Aspergillus Giganteus ◽  
Fungal Plant Pathogens ◽  
Total Inhibition

A purified preparation of antifungal protein (AFP) from Aspergillus giganteus exhibited potent antifungal activity against the phytopathogenic fungi Magnaporthe grisea and Fusarium moniliforme, as well as the oomycete pathogen Phytophthora infestans. Under conditions of total inhibition of fungal growth, no toxicity of AFP toward rice protoplasts was observed. Additionally, application of AFP on rice plants completely inhibited M. grisea growth. These results are discussed in relation to the potential of the afp gene to enhance crop protection against fungal pathogens in transgenic plants.

scholarly journals Bioactive Metabolites from the Endophytic Fungus Aspergillus sp. SPH2

2021 ◽  
Vol 7 (2) ◽  
pp. 109
Author(s):  
Viridiana Morales-Sánchez ◽  
Carmen E. Díaz ◽  
Elena Trujillo ◽  
Sonia A. Olmeda ◽  
Felix Valcarcel ◽  
...  
Keyword(s):  
Endophytic Fungus ◽  
Plant Pathogens ◽  
Insect Pests ◽  
Ethyl Acetate Extract ◽  
Rhopalosiphum Padi ◽  
Fungal Growth ◽  
Bioactive Metabolites ◽  
Endemic Plant ◽  
Antifungal Effects ◽  
Aspergillus Sp

In the current study, an ethyl acetate extract from the endophytic fungus Aspergillus sp. SPH2 isolated from the stem parts of the endemic plant Bethencourtia palmensis was screened for its biocontrol properties against plant pathogens (Fusarium moniliforme, Alternaria alternata, and Botrytis cinerea), insect pests (Spodoptera littoralis, Myzus persicae, Rhopalosiphum padi), plant parasites (Meloidogyne javanica), and ticks (Hyalomma lusitanicum). SPH2 gave extracts with strong fungicidal and ixodicidal effects at different fermentation times. The bioguided isolation of these extracts gave compounds 1–3. Mellein (1) showed strong ixodicidal effects and was also fungicidal. This is the first report on the ixodicidal effects of 1. Neoaspergillic acid (2) showed potent antifungal effects. Compound 2 appeared during the exponential phase of the fungal growth while neohydroxyaspergillic acid (3) appeared during the stationary phase, suggesting that 2 is the biosynthetic precursor of 3. The mycotoxin ochratoxin A was not detected under the fermentation conditions used in this work. Therefore, SPH2 could be a potential biotechnological tool for the production of ixodicidal extracts rich in mellein.

Purification and characterization of an exochitinase from Bacillus thuringiensis subsp. aizawai and its action against phytopathogenic fungi

2006 ◽  
Vol 52 (7) ◽  
pp. 651-657 ◽  
Author(s):  
Luis Morales de la Vega ◽  
J Eleazar Barboza-Corona ◽  
Maria G Aguilar-Uscanga ◽  
Mario Ramírez-Lepe
Keyword(s):  
Bacillus Thuringiensis ◽  
Sodium Dodecyl ◽  
Sclerotium Rolfsii ◽  
Phytopathogenic Fungi ◽  
Purification And Characterization ◽  
Chitinolytic Enzyme ◽  
Bacillus Thuringiensis Subsp ◽  
Sds Page ◽  
Fusarium Sp

A chitinolytic enzyme from Bacillus thuringiensis subsp. aizawai has been purified and its molecular mass was estimated ca. 66 kDa by sodium dodecyl sulfate – polyacryamide gel electrophoresis (SDS–PAGE). The enzyme was able to hydrolyze chitin to chitobiosides but not carboxymethylcellulose, cellulose, pullulan, and laminarin. Optimal pH and temperature were detected at 6 and 50 °C, respectively. Stability, in the absence of substrate, was observed at temperatures less than 60 °C and pH between 5 and 8. Enzyme activity was significantly inhibited by K+ and EDTA and completely inhibited by Hg2+. Purified chitinase showed lytic activity against cell walls from six phytopathogenic fungi and inhibited the mycelial growth of both Fusarium sp. and Sclerotium rolfsii. The biocontrol efficacy of the enzyme was tested in the protection of bean seeds infested with six phytopathogenic fungi.Key words: chitinase, Bacillus thuringiensis, purification, phytopathogenic fungi.

scholarly journals Filamentous fungi isolated from sand and water of "Bairro Novo" and "Casa Caiada" beaches, Olinda, Pernambuco, Brazil

2008 ◽  
Vol 68 (3) ◽  
pp. 577-582 ◽  
Author(s):  
DNF. Gomes ◽  
MAQ. Cavalcanti ◽  
MJS. Fernandes ◽  
DMM. Lima ◽  
JZO. Passavante
Keyword(s):  
Water Samples ◽  
Water Surface ◽  
High Tide ◽  
Sand Sample ◽  
Distilled Water ◽  
Sabouraud Agar ◽  
Sand Surface ◽  
Heterotrophic Microorganisms ◽  
Petri Dishes ◽  
Dry And Rainy Seasons

Fungi comprehend a heterogeneous group of heterotrophic microorganisms that act as saprobes or parasites or, less frequently, as symbionts living in association with other organisms. They are cosmopolitan and important components of ecosystems. Considering the small number of Brazilian papers on the filamentous mycota in marine environments, and the need to improve knowledge of the diversity of these microfungi in "Casa Caiada" and "Bairro Novo" beaches, Olinda, PE, the aim of this work was to isolate and identify the fungi from sand and water samples of these ecosystems. Thirty two samplings of sand (surface and 20 cm deep) and water (surface and 1 m deep) were carried out during the dry and rainy seasons, in low and high tide. From each sand sample, a suspension was made with 50 g of sand diluted in 90 mL of sterilized distilled water. From each sand suspension and water sample, 0.5 mL was spread, in triplicate, onto Petri dishes containing Sabouraud Agar added of chloramphenicol. The plates were incubated at 28 °C (±2 °C). Fifty seven species were isolated, identified, and classified in 20 genera. Aspergillus and Penicillium were the most frequent genera in both sand and water, with a total of 11 and 19 species, respectively.

scholarly journals Novel Bifunctional Inhibitor of Xylanase and Aspartic Protease: Implications for Inhibition of Fungal Growth

2001 ◽  
Vol 45 (7) ◽  
pp. 2008-2017 ◽  
Author(s):  
Chandravanu Dash ◽  
Absar Ahmad ◽  
Devyani Nath ◽  
Mala Rao
Keyword(s):  
Growth Inhibition ◽  
Fungal Growth ◽  
Phytopathogenic Fungi ◽  
Aspartic Protease ◽  
Cellular Growth ◽  
Alternative Mechanism ◽  
Trinitrobenzenesulfonic Acid ◽  
Woodward’S Reagent K ◽  
Bifunctional Inhibitor ◽  
Fungal Growth Inhibition

ABSTRACT A novel bifunctional inhibitor (ATBI) from an extremophilicBacillus sp. exhibiting an activity against phytopathogenic fungi, including Alternaria, Aspergillus, Curvularia, Colletotricum, Fusarium, and Phomopsis species, and the saprophytic fungus Trichoderma sp. has been investigated. The 50% inhibitory concentrations of ATBI ranged from 0.30 to 5.9 μg/ml, whereas the MIC varied from 0.60 to 3.5 μg/ml for the fungal growth inhibition. The negative charge and the absence of periodic secondary structure in ATBI suggested an alternative mechanism for fungal growth inhibition. Rescue of fungal growth inhibition by the hydrolytic products of xylanase and aspartic protease indicated the involvement of these enzymes in cellular growth. The chemical modification of Asp or Glu or Lys residues of ATBI by 2,4,6-trinitrobenzenesulfonic acid and Woodward's reagent K, respectively, abolished its antifungal activity. In addition, ATBI also inhibited xylanase and aspartic protease competitively, withKi values 1.75 and 3.25 μM, respectively. Our discovery led us to envisage a paradigm shift in the concept of fungal growth inhibition for the role of antixylanolytic activity. Here we report for the first time a novel class of antifungal peptide, exhibiting bifunctional inhibitory activity.

scholarly journals Change the condition of spring wheat when adding bacterial-humic preparation to herbicides

2021 ◽  
pp. 37-46
Author(s):  
L. N. Korobova ◽  
T. A. Kizimova ◽  
A. A. Pobelenskaya ◽  
T. G. Lomova
Keyword(s):  
Spring Wheat ◽  
Seed Quality ◽  
Bipolaris Sorokiniana ◽  
Forest Steppe ◽  
Northern Forest ◽  
Primary Roots ◽  
Hexyl Ester ◽  
Production Experiment ◽  
Fusarium Sp

The authors studied the effect of the bacterial-humic preparation AFG-b containing the spore-forming bacteria Bacillus subtilis and Bacillus amyloliquefaciens in a production experiment in the northern forest-steppe of the Novosibirsk Priob’ye region. The preparation was used on midearly spring wheat, which forms grain at the level of valuable wheat. The drug was used as an antistressant together with herbicides against dicotyledonous and monocotyledonous plants. The tank mixture used was metsulfuron-methyl, fenoxaprop-P-ethyl with the antidote cloquintoset-mexyl and 2-ethyl hexyl ester of 2,4-D with florasulam. The bacterial-humic preparation AFG-b is known to level out herbicide stress in wheat and improve plant health. It improves the condition of leaf cell membranes by preventing the escape of electrolytes from the cells. On the roots of plants one month after applying the antistressant, the authors observed a 1.5-2 times reduction in the development and prevalence of root rot of fusarium-helminthosporiosis etiology. The authors also marked the most pronounced phytosanitary effect of the preparation’s bacteria, which are antagonists of phytopatho- gens for plants’ primary roots and epicotyl. An increase in plant productivity manifests the anti-stress and growth-stimulating effect of AFG-b. During the growing season of 2020, the bio preparation combined with herbicides provided a reliable increase of 40.2% of the grain of spring wheat and improved its quality by enhancing the protein and gluten content. Under 2019 conditions, AFG-b increased grain yield relative to herbicides by about 8% and did not affect grain quality. Application of AFG-b as an anti-stressant is not accompanied by improvement of seed quality of the new crop. It does not improve its phytosanitary status in infestation by phytopathogens Bipolaris sorokiniana, Fusarium sp., Alternaria, Stagonospora nodorum, Penicillium and Aspergillus relative to herbicides alone.

scholarly journals Temporal patterns of seed quality development, decline, and timing of maximum quality during seed development and maturation

2019 ◽  
Vol 29 (2) ◽  
pp. 135-142 ◽  
Author(s):  
Richard H. Ellis
Keyword(s):  
Seed Development ◽  
Seed Quality ◽  
Single Point ◽  
Temporal Patterns ◽  
Relative Sensitivity ◽  
Quality Development ◽  
Seed Filling ◽  
Seed Deterioration ◽  
Highly Sensitive ◽  
Harvest Maturity

AbstractThe long-standing hypothesis that seed quality improves during seed filling, is greatest at the end of seed filling, and declines thereafter (because seed deterioration was assumed to begin then), provided a template for research in seed quality development. It was rejected by investigations where seed quality was shown to improve throughout both seed development and maturation until harvest maturity, before seed deterioration was first observed. Several other temporal patterns of seed quality development and decline have also been reported. These are portrayed and compared. The assessment suggests that the original hypothesis was too simple, because it combined several component hypotheses: (a) the seed improvement (only) phase ends before seed deterioration (only) commences; (b) there is only a brief single point in time during seed development and maturation when, in all circumstances, seed quality is maximal; (c) the seed quality improvement phase coincides perfectly with seed filling, with deterioration only post-seed filling. It is concluded that the search for the single point of maximum seed quality was a false quest because (a) seed improvement and deterioration may cycle (sequentially if not simultaneously) during seed development and maturation; (b) the relative sensitivity of the rates of improvement and deterioration to environment may differ; (c) the period of maximum quality may be brief or extended. Hence, when maximum quality is first attained, and for how long it is maintained, during seed development and maturation varies with genotype and environment. This is pertinent to quality seed production in current and future climates as it will be affected by climate change and a likelihood of more frequent coincidence of brief periods of extreme temperatures with highly sensitive phases of seed development and maturation. This is a possible tipping point for food security and for ecological diversity.

scholarly journals Optimization and sensitivity analysis of fast ethanol assay in maize seeds

2019 ◽  
Vol 41 (1) ◽  
pp. 97-107 ◽  
Author(s):  
Damrongvudhi Onwimol ◽  
Thunyapuk Rongsangchaicharean ◽  
Pitipong Thobunluepop ◽  
Tanapon Chaisan ◽  
Wanchai Chanprasert
Keyword(s):  
Quality Assessment ◽  
Ethanol Production ◽  
Seed Quality ◽  
Storage Conditions ◽  
Ambient Conditions ◽  
Maize Seed ◽  
Seed Deterioration ◽  
Maize Seeds ◽  
Hermetic Seal

Abstract: The evaluation of seed deterioration is very important to control the quality of the seeds stored. This study aimed to investigate the potential of fast ethanol assay for seed quality assessment of maize stored under different conditions. The first experiment was to determine the incubating temperature, incubating time, and amount of seed used in the assay. The results showed that the best protocol for the detection of headspace ethanol was incubation of 3 g of maize seed with 20% moisture content (wet basis) in a 20 mL gas chromatography vial at 70 °C for 1.5 h. The assay induced approximately 200-700 µg.L-1 of headspace ethanol, which was sufficient to identify seeds with different vigour levels. In the second experiment, the optimal conditions were used for quality assessment in aged maize seed stored for 12 months under different storage conditions. The increase in the ethanol production of stored maize seed under the controlled conditions (15 °C and 20% RH in the hermetic seal) was lower than under ambient conditions. The ethanol production levels of maize seed samples at the start of storage was significantly lesser than at six months storage (p < 0.05). The test limitations in deteriorated seed with different cultivars and ages will be discussed.

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