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Continuous microwave-assisted flow synthesis has been used as a simple, more efficient, and low-cost route to fabricate a range of nanosized (<100 nm) strontium-substituted calcium phosphates. In this study, fine nanopowder was synthesized via a continuous flow synthesis with microwave assistance from the solutions of calcium nitrate tetrahydrate (with strontium nitrate as Sr2+ ion source) and diammonium hydrogen phosphate at pH 10 with a time duration of 5 min. The morphological characterization of the obtained powder has been carried out by employing techniques such as transmission electron microscopy, X-ray diffraction, and Brunauer–Emmett–Teller surface area analysis. The chemical structural analysis to evaluate the surface properties was made by using X-ray photoelectron spectroscopy. Zeta potential analysis was performed to evaluate the colloidal stability of the particles. Antimicrobial studies were performed for all the compositions using four bacterial strains and an opportunistic human fungal pathogen Macrophomina phaseolina. It was found that the nanoproduct with high strontium content (15 wt% of strontium) showed pronounced antibacterial potential against M. luteus while it completely arrested the fungal growth after 48 h by all of its concentrations. Thus the synthesis strategy described herein facilitated the rapid production of nanosized Sr-substituted CaPs with excellent biological performance suitable for a bone replacement application. [ABSTRACT FROM AUTHOR]

Quinoa (Chenopodium quinoa Willd.) is a newly introduced crop in Pakistan. We evaluated the antifungal efficacy of root extracts of 4-quinoa varieties (PI 596293, Ames 13730, Ames 13737 and PI 634919) against the most harmful soil inhabiting fungal pathogen Macrophomina phaseolina (Tassi) Goid. Methanolic root extracts (1 to 5 %) of these varieties reduced the fungal biomass by 33-70 %. Due to its higher antifungal activity, Ames 13737 variety was selected for further studies and fractionated with 4-organic solvents (n-hexane, chloroform, ethyl acetate and n-butanol) based on their increased polarities. All concentrations of chloroform and the lowest concentration of n-butanol (1.562 mg mL-1 ) completely inhibited the pathogen growth. These fractions were further subjected to GC-MS analysis that revealed the presence of 7-antifungal phytoconstituents (decane; undecane; oleic acid; benzene, 1,2,3-trimethyl; cycloheptasiloxane, tetradecamethyl-; cyclohexasiloxane, dodecamethyl- and 9-octadecanoic acid (Z)-, methyl ester). This study concluded that chloroform and n-butanol fractions of root extract of quinoa possess strong antifungal potential against M. phaseolina. [ABSTRACT FROM AUTHOR]

Macrophomina phaseolina is a wide host ranged soil-borne fungal plant pathogen. It infects more than 500 host plant species belonging to 100 families. Many important oil-seed and leguminous crops are known to be attacked by this devastating plant pathogen. In the present study, antifungal potential of flowers of a leguminous tree Acacia nilotica subsp. indica , was assessed against this pathogen through bioassays guided fractionation. Initially, methanolic extracts of 1 %–5 % of leaf, flower, root-bark and stem-bark of the plant species under consideration were evaluated for their antifungal potential against the target pathogen. Among these, the best antifungal activity was shown by flower extract. The reduction in growth of the test fungal strain was 27–49 %, 4–40 % and 2–27 % due to flower, root-bark and leaf extracts, respectivey, over control. Flower extract was partitioned using n- hexane, chloroform, ethyl acetate and n- butanol as the solvents. Bioassays guided study of these fractions of methanolic extract of flower revealed that high antifungal potential was shown by n- hexane and chloroform fractions against M. phaseolina causing 26–53 % and 28–50 % decline in fungal biomass, respectively, as compared to that of control. GC-MS analysis of chloroform fraction revealed the presence of 27 compounds in this fraction. Among these cyclopentanol,-1-methyl (10.93 %) was the predominant compound followed by methyl, 4,4-dimethyl butanoate (7.04 %), 1-pentanol (6.80 %), 2-propanol, 1-cyclopropyl (6.11 %), 1H,imidazole-4-5-dihydro-2-methyl (5.93 %), trichloroethane (5.91 %), carbonic acid-ethyl hexyl ester (4.59 %), 1,4-butandiol,2,3-bis(methylene)- (4.54 %) and [S]-3,4-dimethyl pentanol (4.48 %). • Macrophomina phaseolina , a soil-borne fungal pathogen, infects over 500 plant species across 100 families, notably oil-seed and leguminous crops. • The study assessed the antifungal properties of Acacia nilotica subsp. indica, focusing on methanolic extracts from various plant parts. • Flower extracts exhibited the highest antifungal activity, reducing fungal growth by 27–49 %. • The methanolic flower extract was fractionated using n-hexane, chloroform, ethyl acetate, and n-butanol, with n-hexane and chloroform fractions showing significant antifungal effects (26–53 % and 28–50 % reduction in fungal biomass, respectively). • GC-MS analysis of the chloroform fraction identified 27 compounds, with cyclopentanol,-1-methyl (10.93 %) being the predominant compound. [ABSTRACT FROM AUTHOR]

In the present study, two Aspergillus species as biocontrol agents together with Chenopodium quinoa dry biomass were used to investigate their effects on histochemical features of mungbean plant inoculated with M. phaseolina. In a pot experiment, Aspergillus flavipes and Aspergillus versicolor were added either alone or together with 1%, 2%, and 3% dry biomass of quinoa (DBQ) to the pot soil already inoculated with M. phaseolina. After 4 weeks of sowing, root and lower‐stem sections of the mungbean plants were stained with ferric chloride, phloroglucinol‐HCl and Lugol's iodine to detect the presence of polyphenols, lignin, and starch granules, respectively, and observed under light microscope. Stem and root sections were also observed under scanning electron microscope (SEM) to reveal the effect of soil amendments on cell structures. The findings revealed that mungbean plant cross sections from all the treatments except positive control (only inoculated with M. phaseolina) showed very clear cell structures. In positive control, distorted, fragmented, and collapsed cell structures were observed. Moreover, M. phaseolina blocked vascular vessels in comparison to negative control where the cell structures were intact and normal in size. Plant sections from treatments with A. flavipes and A. versicolor alone or together with DBQ were without pathogen colonization, with normal cell structures and a high deposition of gel. The results suggested that the two Aspergillus spp. and C. quinoa induced defense responses in mungbean plants. Highlights: Macrophomina phaseolina causes significant yield losses in mungbean.Pot soil was amended with two species of Aspergillus as biocontrol agents along with plant biomass.Aspergillus spp. markedly saved the root and stem structures from the damage caused by M. phaseolina. [ABSTRACT FROM AUTHOR]

Mungbean production is affected by a fungal pathogen Macrophomina phaseolina. A pot experiment was carried out to check the effect of quinoa (Chenopodium quinoa Willd.) dry biomass on the histopathological features of mungbean exposed to M. phaseolina. For this, 1%, 2% and 3% (wt/wt) of C. quinoa dry biomass was mixed in the soil inoculated with M. phaseolina. The highest disease incidence (36%) was recorded in the positive control (only M. phaseolina). Different treatments of quinoa dry mass reduced disease incidence to 4–7%. After 4 weeks of germination, stem and root sections were stained in phloroglucinol‐HCl, ferric chloride and Lugol's iodine stains for the detection of lignin, polyphenols and starch granules, respectively, and studied under light microscope. Plants of positive control showed damaged cells, and heavy deposition of lignin, phenolics and starch granules as compared to plants of the negative control and those grown in the soil amended with different doses of dry biomass of quinoa. For better understanding, plant root and stem sections were studied under a scanning electron microscope. Plant sections from positive control exhibited the presence of M. phaseolina sclerotial bodies and hyphal growth, whereas in negative control normal cell structures were observed. However, C. quinoa amended stem and root sections revealed the presence of high gel deposition with normal cell structures and no pathogen establishment. This study concludes that application of C. quinoa is an effective and natural remedy to activate the resistance mechanism in plants and to combat the adverse effects of M. phaseolina. Highlights: Macrophomina phaseolina causes charcoal rot in mungbean.Chenopodium quinoa amendment significantly reduced incidence of charcoal rot disease.M. phaeolina increased concentrations of polyphenols, lignin and starch granules in mungbean. [ABSTRACT FROM AUTHOR]

In the present study, five Penicillium species, namely, P. italicum, P. expansum, P. simplicissimum, P. oxalicum, and P. citrinum, were identified using ITS (internal transcribed spacer) and β-tubulin markers and screened for their in vitro antagonistic potential against a soil-borne fungal pathogen, Macrophomina phaseolina, in a dual-culture plate assay. Among all the tested strains, P. italicum showed the highest antagonistic potential against M. phaseolina by reducing its growth up to 57% over control, followed by P. citrinum (42%), P. simplicissimum (21%), P. expansum (11%), and P. oxalicum (9%). In order to find out the mechanism of action of P. italicum, genomic DNA of M. phaseolina was exposed to P. italicum secondary metabolites. The findings showed that these metabolites completely degraded the fungal DNA after the 48-h incubation period. To further explore the antifungal mechanism of action of P. italicum, chloroform and ethyl acetate fractions of its metabolites were subjected to gas chromatography–mass spectrometry (GC-MS) analysis. The major compounds identified in these fractions were 9,12-octadecadienoic acid (Z,Z)- (25.19%), decane (19.72%), dodecane (18.05%), benzene, nitro- (14.62%), benzene, 1,3,5-trimethyl (14.37%), benzene, 1,4-diethyl (11.62%), 1,2-benzenedicarboxylic acid, mono(2-ethylhexyl) ester (9.02%), and 1-nonadecene (8.99%), which could be responsible for control of M. phaseolina growth. [ABSTRACT FROM AUTHOR]

Hundreds of plant species, including many economically important crop plants, are attacked by a highly destructive soil-borne fungus Macrophomina phaseolina (Tassi) Goid. In the present study, methanolic root extract of septicweed [Senna occidentalis (L.) Link] was evaluated against this fungus. Different concentrations of the extract (0.5 to 3.0%) considerably decreased fungal biomass by 33–43%. Nine compounds were identified when the extract was analyzed by GC-MS. The major compound was 11-octadecanoic acid, methyl ester (26.49%) followed by (5β)pregnane-3,20β-diol, 14α d-mannose (13.85%);, 18α-[4-methyl-3-oxo-(1-oxa-4-azabutane-1,4-diyl)]-, diacetate (13.61%); ethyl isoallocholate (11.37%); pentadecanoic acid, 14-methyl-, methyl ester (11.01%); and 9,12- octadecadienoic acid, methyl ester, (E,E)- (9.76%), which might be the cause of antifungal activity. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate the antagonistic potential of Aspergillus spp. against Macrophomina phaseolina. All the tested species namely Aspergillus niger, Aspergillus terreus, Aspergillus flavipes, Aspergillus flavus and Aspergillus sydowii were identified by rDNA sequencing of ITS and β-tubulin regions prior to determine their antagonistic behaviour against the pathogen by using dual culture technique. A. flavipes proved to be the most effective in reducing the colony diameter of M. phaseolina (53%) followed by A. niger (41%) and A. flavus (37%) over control, whereas A. sydowii and A. terreus were the least effective with 6.2% and 5% in vitro biocontrol potentials, respectively. The secondary metabolites produced by A. flavipes were tested against the genomic DNA of M. phaseolina to understand the mechanism of antagonism. The bioactive metabolites completely degraded the pathogenic fungal DNA at higher concentrations of 400% and 500% after 24 h. Moreover, the chloroform and ethyl acetate fractions of culture filtrates of A. flavipes were subjected to GC–MS analysis for the identification of potential antimicrobial compounds and a total of 14 and 8 compounds were identified in these fractions, respectively. Among these 9,12-octadecadienoic acid (Z,Z)- followed by 1,2-benzedicarboxylic acid, diisooctyl ester; decane; hexadecanoic acid,2-hydroxy-1-(hydroxymethyl) ethyl ester; benzene, 1,2,3-trimethyl; n-hexadecanoic acid and naphthalene were the predominant compounds with peak areas of 31.72%, 26.27%, 18.47%, 10.62%, 6.82%, 6.04% and 5.67%, respectively. Literature shows that some of identified compounds possess antimicrobial properties, which might be responsible for control of M. phaseolina. [ABSTRACT FROM AUTHOR]

The soil-borne fungal plant pathogen Macrophomina phaseolina (Tassi) Goid. causes rot disease in about 500 plant species worldwide. This study was conducted to assess the antifungal potential of an allelopathic grass Imperata cylindrica (L.) Beauv. for the management of this devastating plant pathogen. In laboratory bioassays, various concentrations viz. 0, 0.5, 1.0, …, 3.0 g 100 mL-1 of methanolic shoot, root and inflorescence extracts of the test allelopathic grass were appraised for their antifungal activity against the pathogen. Generally, higher concentrations of methanolic extracts of all the three parts of the grass exhibited variable antifungal activity. Shoot extract proved to be the most effective. All the concentrations of shoot extract significantly reduced the fungal biomass by 29–76% over control. Methanolic shoot extract was further fractionated using n-hexane, chloroform, ethyl acetate and n-butanol. In antifungal activity bioassays of these fractions, chloroform fraction was found to be the most effective followed by n-hexane and aqueous fractions. All the concentrations of these fractions significantly reduced fungal biomass. Various concentrations of n-hexane, chloroform and aqueous fraction reduced fungal biomass by 27–97%, 68–100% and 32–100%, respectively. Present study concludes that chloroform fraction of methanol shoot extract of I. cylindrica possesses highly active antifungal constituents for the management of M. phaseolina. [ABSTRACT FROM AUTHOR]

Macrophomina phaseolina (Tassi) Goid is a destructive fungal phytopathogen causing diseases in hundreds of plant species. No registered fungicide is available sofar to control this pathogen. This study was carried out to explore the antifungal activity of methanolic extracts of different parts of Eclipta alba (L.) Hassk, a weed of family Asteraceae, against M. phaseolina. Different concentrations (0, 1, 2, 3, 4 and 5%) of methanolic extracts of leaf, stem, root and inflorescence of this weed were evaluated against the target fungal pathogen using malt extract broth as growth medium. In general, extracts of all the plant parts exhibited variable antifungal activity. There was a linear and inverse relationship between fungal biomass and extract concentrations. Leaf and stem extracts showed the best antifungal activities resulting in up to 64% and 61% decrease in biomass of M. phaseolina, respectively. Methanolic extracts of root and inflorescence were proved comparatively less effective than extracts of other plant parts and reduced fungal biomass up to 32% and 19%, respectively. [ABSTRACT FROM AUTHOR]

Macrophomina phaseolina is the cause of charcoal rot in green gram [Vigna radiata (L.) Wilczek] and black gram [Vigna mungo (L.) Hepper]. A pot experiment was carried out in March 2013 to study the effect of soil amendment with a biological control agent Trichoderma harzianum and dry biomass of a brassicaceous weed Sisymbrium irio on charcoal rot disease of green gram. The present experiment was a continuation of that study and carried out in the same pots in September 2013 to study the effect of the soil amendments on crop growth of black gram. In general, number of leaves, and various root and shoot growth parameters were significantly decreased due to M. phaseolina inoculation. Application of 1, 2 and 3% dry biomass of S. irio or T. harzianum separately failed to alleviate biotic stress of M. phaseolina. However, combined application of 1% dry biomass of S. irio and T. harzianum significantly increased number of leaves by 23% over positive control inoculated only with M. phaseolina. Various parameters of root and shoot growth were also higher in this treatment as compared to other soil amendment treatments. [ABSTRACT FROM AUTHOR]

In vitro bioassays were carried out to evaluate antagonistic behavior of seven species of Trichoderma namely T. pseudokoningii, T. harzianum, T. reesei, T. koningii, T. hanatus, T. viridi and T. aureoviridi, against two highly problematic soil-borne plant pathogenic fungi viz. Fusarium oxysporum f. sp. lycopersici (Sacc.) Snyder & Hansn and Macrophomina phaseolina (Tassi) Goid. All the Trichoderma species exhibited pronounced antagonistic behavior against the target fungal pathogens in dual cultures resulting in 45-65% and 59-74% reduction in radial growth of M. phaseolina and F. oxysporum f. sp. lycopersici, respectively. T. harzianum was found to be the most effective biocontrol agent against both the fungal pathogens followed by T. aureoviridi and T. hanatus. [ABSTRACT FROM AUTHOR]

Methanolic leaf and fruit extracts of Datura metel were found highly effective in suppressing against Macrophomina phaseolina, the cause of charcoal rot disease. These extracts were further subjected to successive fractionation with n-hexane, chloroform, ethyl acetate and n-butanol. All the concentrations (3.125–200 mg mL−1) of chloroform, ethyl acetate and n-butanol fractions of leaf extract, and n-hexane fraction of fruit extract completely inhibited the target fungal growth. Two compounds A and B from the n-hexane fraction of fruit extract and compound C from n-butanol fraction of leaf extract were obtained by TLC. Compound B exhibited the best antifungal activity with an MIC value of 7.81 µg mL−1 that was at par with that of commercial fungicide mancozeb (80% w/w). This study concludes that M. phaseolina can be effectively controlled by natural antifungal compounds in n-hexane fraction of methanolic fruit extract of D. metel. [ABSTRACT FROM PUBLISHER]

Antifungal activity of methanol and n-hexane leaf, stem, root and inflorescence extracts (1, 2, 3 and 4% w/v) of three Chenopodium species (family Chenopodiaceae) namely Chenopodium album L., Chenopodium murale L. and Chenopodium ambrosioides L. was investigated against Macrophomina phaseolina (Tassi) G. Goid., a soil-borne fungal plant pathogen that has a broad host range and wide geographical distribution. All the extracts of the three Chenopodium species significantly suppressed the test fungal growth. However, there was marked variation among the various extract treatments. Methanol inflorescence extract of C. album exhibited highest antifungal activity resulting in up to 96% reduction in fungal biomass production. By contrast, methanol leaf extract of the same species exhibited least antifungal activity where 21-44% reduction in fungal biomass was recorded due to various employed extract concentrations. The various methanol extracts of C. murale and C. ambrosioides decreased fungal biomass by 62-90 and 50-84%, respectively. Similarly, various n-hexane extracts of C. album, C. murale and C. ambrosioides reduced fungal biomass by 60-94, 43-90 and 49-86%, respectively. [ABSTRACT FROM AUTHOR]

The present study demonstrated that chitin-based nanofibers (CNFs) trigger the chitinase genes (PGIP1 and CaChi2), while elevating salicylic acid that can protect plants against pathogens. Cross-talk between this genetic induction and salicylic-acid-mediated immune response was also observed, which may arm a plant against multiple pathovars. Crab and mushroom based CNFs were synthesized by electrospinning and ball milling techniques. Plants (mung bean, Vigna radiata) (pepper, Capsicum annuum) were pre-inoculated with CNFs and treated with the pathogens Scrolotium rolfsii for pepper and Macrophomina phaseolina for mung bean and shrimp-based CNFs were used as a control. Treated plants had elevated levels of chitinase genes in response to CNFs at inoculation concentrations <10 mg/mL both in soil and media, to protect them against the pathogenic fungal disease. After 24 h of exposure to the pathogens, qRT-PCR showed genes class II chitinase gene (CaChi2) and polygalacturonase inhibitor protein 1 (PGIP1) to be up-regulated in both root and shoot at 0.1 and 1 mg/mL of inoculation, respectively. The ball milled mushroom CNFs were sufficient to trigger the membrane based enzymes with less diameter (≥15 nm) to be most efficient versus others. In vitro analysis showed IC 50 of ball milled mushroom CNFs to be most efficient in limiting the growth of fungal biomass. Further trigger-like effects were prominent in reducing pathogenic fungal spread in both species. [ABSTRACT FROM AUTHOR]