Maximum Mycelial Inhibition Research Articles

Effect of Cow Urine and Culture Filtrates of Trichoderma isolate S-13 on Fungal Pathogens of Basmati Rice

Rice (Oryza sativa L.) is the principle food crop for majority population of the world. Basmati rice is a unique crop of Himalaya comprising good quality characters and aroma. Basmati rice is being infected by numerous diseases. To manage these diseases, fungicides being used for years. This leads to the residual effects of fungicides on grains and soils so there is needs for alternate approaches to the manage disease. Hence use of cow urine and Trichoderma isolate S-13 is considered as the sustainable approach for management of important diseases of basmati rice. In this study we used different concentration of cow urine, Trichoderma isolate S-13, and Propiconazole (control check) against brown spot and bakanae disease of rice. Among these the maximum mycelial inhibition observed in Trichoderma isolate S-13 @15per cent (66.33per cent) followed by cow urine @15per cent (52.59 per cent). In Bakanae disease the maximum inhibition observed in Trichoderma isolate S-13 @ 15per cent (58.89 per cent) followed by cow urine@15per cent (49.26 per cent).

Bio-efficacy of Alcoholic Extracts of Botanicals to Mitigate Pea Root Rot Caused by Fusarium solani f.sp. pisi

Pea root rot caused by Fusarium solani f. sp. pisi has been observed as an alarming problem in pea growing regions of Himachal Pradesh and poses major constraints in pea cultivations. The alcoholic leaf extracts of four plants viz., Eupatorium adenophorum, Eucalyptus sp., Vitex negundo and Ageratum conyzoides were evaluated at different concentrations for their efficacy against F. solani f. sp. pisi under in vitro conditions. Among all extracts, E. adenophorum yielded maximum mycelial inhibition of 77.4 per cent followed by Eucalyptus sp. 74.9 per cent at 25 per cent test concentration. Thus, among all test botanicals, E. adenophorum was found the most efficient against F. solani f. sp. pisi. These findings suggest that E. adenophorum extracts could be used as eco-friendly alternatives to control Fusarium solani f. sp. pisi.

Studies on Anti-Fungal Activity of Different Macro Algal Extracts against Soil Borne Pathogen Sclerotium rolfsii Sacc.

Management of soil-borne plant pathogens is one of the single greatest challenges facing modern agriculture worldwide. Seaweeds are considered as a source of bioactive compounds as they are able to produce a great variety of secondary metabolites characterized by a broad spectrum of biological activities. The seaweeds derived compounds showing broad range of biological activities such as antiviral, antibacterial and antifungal activities. The antimicrobial activity of macro algal extracts is generally analysed using various organic solvents which always present higher efficiency in extracting bioactive compounds. Among the different the solvent extracted macro algal extracts tested, methanol extracts of Sargassum wightii recorded maximum mycelial inhibition (88.22 %) and on par with aqueous extracts recorded 85.78% of mycelial inhibition @ 10% concentration compared to other macro algal extracts.. Among the fifteen macro algal extracts, maximum inhibition of mycelial growth was recorded the Sargassum wightii (Brown algae), Ulva lactuca (Green algae) and Gracilaria salicornia (red algae) at different concentrations. In this study, we have shown that Sargassum wightii has antimicrobial potential against the S. rolfsii. Methanol extract was found to be the best solvent for retention of the antimicrobial activity

Exploitation of indigenous fluorescent pseudomonads against stem and pod rot of groundnut caused by <i>Sclerotium rolfsii</i>

Stem and pod rot of groundnut is an economically important soil borne disease caused by Sclerotium rolfsii Sacc. The present study aimed to evaluate the indigenous bacterial bio control agent Pseudomonas fluorescens strains having multiple traits related to bio control and plant growth promoting activity. Healthy rhizospheric soil from groundnut field was collected from different North Karnataka districts. Nineteen strains of P. fluorescens were isolated by serial dilution technique on King’s B medium. The antagonistic potential of nineteen strains was tested against S. rolfsii by using dual culture technique. The per cent inhibition was highly variable among the nineteen strains of P. fluorescens ranging from 2.59 to 75.18 per cent. Maximum mycelial inhibition of S. rolfsii was recorded by the strain PF-2 (75.18%) followed by PF-3 (72.96%), PF-6 (69.62%) and least inhibition was recorded by PF-13 (2.59%). Five superior strains of P. fluorescens showed fluorescens under UV light, yellowish green pigmentation, rod shaped cells under microscope. Five superior strains were subjected for various biochemical tests and all the isolates were positive for biochemical characterization such as Gram staining, endospore production, catalase, starch hydrolysis, urease test, casein hydrolysis and gelatin liquefy action and negative for KOH and in dole test. Further, these strains were subjected for plant growth promoting traits such as HCN production, IAA production, siderophore production and volatile compounds production. Among these, the strainsviz., PF-2 and PF-3 were scored as strong with respect to antagonism and growth promotion. The strainsPF-6, PF-7 and PF-10 were scored as moderate with light brown colour. Among the tested strains of P. fluorescens, the isolates PF-2 and PF-3 were recorded higher production of siderophore, isolates PF-6, PF-7 and PF-10 showed moderate production of siderophore. The strain PF-2 of P. fluorescens showed highest per cent of mycelial inhibition of S. rolfsii indicating higher production of volatile compounds, followed by PF-3 and PF-6. Whereas, the least mycelial inhibition was recorded by the isolate PF-10 indicating less production of volatile compounds.

Zinc oxide nanoparticles synthesized using Oldenlandia Umbellata leaf extract and their photocatalytic and biological characteristics

The aim of this study was to examine the environmentally friendly green production of zinc oxide nanoparticles (ZnO NPs) utilizing Oldenlandia Umbellata (OU) leaves extract, as well as to study the photo catalytic and biological activities of these particles. XRD, UV-Visible, FT-IR, SEM, EDAX, TEM and Zeta potential studies were used to investigate the purity and properties of as synthesized ZnO NPs. From the FT-IR investigations presenting functional groups were verified. The hexagonal form and wurtzite crystal nature were confirmed by SEM and XRD photographs. The decreasing zeta potential of −23.7 mV suggested the stability of OU-ZnO NPs, which was validated by Zeta potential and EDAX measurements. The OU-ZnO NPs' photo catalytic activity was also examined using their methylene red dye degradation potential. It also has a DPPH test that revealed it had a 66% radical scavenging activity. Furthermore, this substance was proven to be an effective anti-fungal agent against Candida albicans, which demonstrated a maximum mycelial inhibition of 12.5 ± 0.7. Additionally, the biosynthesized nanoparticles had high antibacterial activity verses all of the microbiological strains tested to varying degrees.

In-vitro screening of antagonistic potential of native endophyte strains of banana (Musa spp.) against Fusarium oxysporum f. sp. cubense TR4 causing Fusarium wilt of banana

The experiment was done in the Department of Plant Pathology, RPCAU, Pusa, Bihar during 2021-22 to identify the antagonistic potential of native endophytes of bananas against FocTR4. An in-vitro investigation revealed that only four bacterial endophytes, GNBE4, GNBE9, GNBE12, and GNBE14, showed significant antagonistic effects against FocTR4out of 18 screened endophytes (13 bacterial and 5 fungal) of banana. The GNBE4 (Alcaligens sp.) showed maximum mycelial inhibition (75.18%), followed by GNBE9 (Stenotrophomonas maltophilia) (71.90%) and GNBE12 (Staphylococcus warneri) (70.69%), while lowest in GNBE14 (Bacillus subtilis) (61.07%). Among the fungal endophytes, the maximum mycelial growth inhibition was shown in RzFE and LfFE (42.78%) followed by PsdFE (36.11%), while lowest in PtFE1 (26.67%). Apart from that already identified antagonistic PGPR like Pseudomonas fluorescens was obtained from the Department of Microbiology were tested which significantly suppressed the mycelial growth of fungus having a mycelial inhibition of 70.01 %.

Evaluation of Bio-Control Agents against Fusarium Wilt of Cucumber

The experiment was carried out in Department of Plant Pathology, Dr Yashwant Singh Parmar University of Horticulture and Forestry, Nauni, Solan, Himachal Pradesh, India during cropping season of May to August in year 2018–2019 to study the efficacy of fungal and bacterial bio-control agents in managing the Fusarium wilt of cucumber. Different fungal and bacterial bio-control agents were thus tested under laboratory conditions for their efficacy in inhibiting the mycelial growth of Fusarium oxysporum by using dual culture technique and streak plate method, respectively. Among fungal bio-control agents, Trichoderma harzianum was found most effective with 61.08% inhibition of mycelial growth of F. oxysporum followed by Trichoderma virens with 57.51% mycelial inhibition whereas, among bacterial bio-control agents, maximum mycelial inhibition of 45.69% was observed in Pseudomonas fluorescens. During the cropping season, seed, and soil treatment with effective fungal and bacterial bioagents was carried out under field conditions. Seed treatment and soil application of Trichoderma harzianum was found effective with disease control of 48.25% followed by Trichoderma virens which is proved to be efficacious with 42% disease control against Fusarium wilt of cucumber.

Biological control of charcoal rot of sesame caused by Macrophomina phaseolina

The potential of bio-agents for the management of sesame root rot caused by Macrophomina phaseolina was evaluated under in vitro conditions. The isolates of bio-agents used for the management of root rot ofsesame were Trichoderma viride, Trichoderma harzianum and Pseudomonas fluorescens. The growth of T. viride, T. harzianum and P. fluorescens was observed in dual culture. The maximum mycelial growth inhibition was showed by T. harzianum by 66.94% followed by T. viride by 59.9% and then by P. fluorescens by 59.9%. The volatile and non-volatile compounds produced by different bio-agentsinhibited the colony growth of M. phaseolina. Maximum mycelial growth inhibition was showed byT. harzianum by59.4% by the production of volatile compounds followed by T. viride and P. fluorescens. By the production of non-volatile compounds the maximummycelial inhibition was done by T. harzianum by 59.9%, again followed by T. viride and P. fluorescens. Biological control has become an alternate and most important part of plant disease management as chemical pesticides possess harmful effects on environment and human health.

Differential Antimycotic and Antioxidant Potentials of Chemically Synthesized Zinc-Based Nanoparticles Derived from Different Reducing/Complexing Agents against Pathogenic Fungi of Maize Crop.

The present study aimed for the synthesis, characterization, and comparative evaluation of anti-oxidant and anti-fungal potentials of zinc-based nanoparticles (ZnNPs) by using different reducing or organic complexing-capping agents. The synthesized ZnNPs exhibited quasi-spherical to hexagonal shapes with average particle sizes ranging from 8 to 210 nm. The UV-Vis spectroscopy of the prepared ZnNPs showed variation in the appearance of characteristic absorption peak(s) for the various reducing/complexing agents i.e., 210 (NaOH and NaBH4), 220 (albumin, and thiourea), 260 and 330 (starch), and 351 nm (cellulose) for wavelengths spanning over 190–800 nm. The FT-IR spectroscopy of the synthesized ZnNPs depicted the functional chemical group diversity. On comparing the antioxidant potential of these ZnNPs, NaOH as reducing agent, (NaOH (RA)) derived ZnNPs presented significantly higher DPPH radical scavenging potential compared to other ZnNPs. The anti-mycotic potential of the ZnNPs as performed through an agar well diffusion assay exhibited variability in the extent of inhibition of the fungal mycelia with maximum inhibition at the highest concentration (40 mg L−1). The NaOH (RA)-derived ZnNPs showcased maximum mycelial inhibition compared to other ZnNPs. Further, incubation of the total genomic DNA with the most effective NaOH (RA)-derived ZnNPs led to intercalation or disintegration of the DNA of all the three fungal pathogens of maize with maximum DNA degrading effect on Macrophomina phaseolina genomic DNA. This study thus identified that differences in size and surface functionalization with the protein (albumin)/polysaccharides (starch, cellulose) diminishes the anti-oxidant and anti-mycotic potential of the generated ZnNPs. However, the NaOH emerged as the best reducing agent for the generation of uniform nano-scale ZnNPs which possessed comparably greater anti-oxidant and antimycotic activities against the three test maize pathogenic fungal cultures.

Sustainable management of chickpea wilt incited by Fusarium oxysporum f. sp. ciceri using plant extracts

Experiments were carried out to evaluate the effect of different plant extracts or botanicals (Azadirachta indica, Ocimum sanctum, Allium cepa, Allium sativum and Zingiber officinale) in suppressing the activity of Fusarium oxysporum f. sp. ciceri (Foc) responsible for inciting the wilt in chickpea. Different concentrations of plant extracts (10%, 20%, 30% and 40%, respectively) prepared in the laboratory were tested for their antagonistic ability under in-vitro conditions. Later, seed treatment using 40% concentration of the extracts were tried in pots. Amongst the different extracts, leaf extract of A. indica caused maximum mycelial inhibition of the pathogen (45.09%, 53.41%, 68.86% and 84.59%, respectively) at all the different concentrations during its culture assay in the Petri plates, while during pot trials it enhanced the percent seed germination to 96.66% and reduced the disease severity to 1.3 against the untreated control which showed 2.4 disease severity score. Moreover, highest number of root nodules (25.67%) and pods/plant (21.67%) with maximum plant yield (18.35 g) was also recorded when A. indica extract was used in comparison to the other treatments beside contributing to highest increase in total chlorophyll and phenolic contents in chickpea plants. Thus, conclusion can be drawn that application of A. indica leaf extract can be recommended for effective management of Fusarium wilt of chickpea.

Antimicrobial Metabolites from Ectomycorrhizal Fungus, Pisolithus tinctorius (Pers.) Coker against Soil Borne Plant Pathogens

Pisolithus tinctorius (Pers.) Coker is an ectomycorrhizal fungus that forms an abundant wealth of biomass in the forest ecosystem, with an untapped treasure of bioactive compounds and secondary metabolites having multifaceted use in health and agrochemical industries. The hidden potential of this fungus is tapped in the current study by using MTP1 isolate of P. tinctorius. The secondary metabolites of P. tinctorius were extracted and tested for their inhibitory efficacy against major soil-borne plant pathogens viz., Fusarium oxysporum f. sp. lycopersici (Sacc.) Synder and Hansen; Macrophomina phaseolina (Goid); Rhizoctonia solani (Kuhn) and Sclerotium rolfsii (Sacc). The cell-free culture (CFC) filtrate of P.tinctorius showed the maximum mycelial inhibition of F. o. f. sp. lycopersici (52.00 %); R. solani (51.92%) and M. phaseolina (48.23%). However, the CFC filtrate mixture did not inhibit the growth of S. rolfsii. The GC-MS analysis of biomolecules composite of ethyl acetate fraction of CFC filtrate indicated the presence of compounds belonging to the nature of fatty acids, aromatic alcohol, and flavonoids. The reduction in the growth of the test pathogens with the increase in the concentration of CFC filtrate and the presence of several unknown compounds in P. tinctorius warrants further study with the purified form of antifungal biomolecules in reducing root rots and wilts incited by the soil-borne phytopathogens.

Screening, identification, and colonization of fungal root endophytes against Dematophora necatrix: a ubiquitous pathogen of fruit trees

The goal of the present research was to ascertain the potential root endophytic fungi against Dematophora necatrix, Hartig, the causal pathogen of white root rot in apples; however, it has an expanded range of hosts across different fruit trees. Out of 36 endophytic fungi segregated from symptomless roots of apple, wheat, maize, marigold, cherry, and garlic plants, only 9 isolates showed inhibitory effect during preliminary screening and were further assayed under in vitro, pot, and field conditions against the white root rot pathogen/disease. Under in vitro conditions, maximum mycelial inhibition of 81.48% was obtained with the isolate Aspergillus aculeatus strain C2. Microscopic studies on interaction between fungal endophyte with hyphal tips of D. necatrix revealed various morphological abnormalities in the hyphae. In glasshouse conditions, seed treatment pursued by soil application with Crinipellis tabtim strain M8 isolate was highly effective and exhibited 93.55% disease control. Similarly, under field conditions, the overall maximum disease control was exhibited by Crinipellis tabtim strain M8 (84.95%). The most promising root endophytes that were identified rely on morphological and ITS sequence analysis. Root colonization assay was performed which revealed maximum endosphere and rhizosphere colonization with Crinipellis tabtim strain M8. Additionally, confocal microscopic illustrations of transverse sections of root cells tenanted by fungal endophytes as compared to untreated control suggested the persistence and establishment of endophytes in the endosphere of apple seedlings. These findings present the first report on colonization of apple roots by fungal root endophytes suggesting an alternative and sustainable approach for management of white root rot disease.

Scanning electron microscopy of bio-fabricated Fe2 O3 nanoparticles and their application to control brown rot of citrus.

Citrus is the leading fruit crop of Pakistan and exported to different parts of the world. Due to suitable weather condition, this crop is affected by different biotic factors which seriously deteriorate its quality and quantity. During the months of November 2018 to January 2019, citrus brown rot symptoms were recurrently observed on sweet oranges in National Agricultural Research Centre (NARC), Islamabad. Causal agent of citrus brown rot was isolated, characterized, and identified as Fusarium oxysporum. For environment-friendly control of this disease, leaf extract of Azadirachta indica was used for the green synthesis of iron oxide (Fe2 O3 ) nanoparticles. These nanoparticles were characterized before their application for disease control. Fourier transform infrared spectroscopy (FTIR) of these synthesized nanoparticles described the presence of stabilizing and reducing compounds like alcohol, phenol, carboxylic acid, and alkaline and aromatic compounds. X-Ray diffraction (XRD) analysis revealed the crystalline nature and size (24 nm) of these nanoparticles. Energy dispersive X-Ray (EDX) analysis elaborated the presence of major elements in the samples. Scanning electron microscopy (SEM) confirmed the spinal shaped morphology of prepared nanoparticles. Successfully synthesized nanoparticles were evaluated for their antifungal potential. Different concentrations of Fe2 O3 nanoparticles were used and maximum mycelial inhibition was observed at 1.0 mg/ml concentration. On the basis of these findings, it could be concluded that Fe2 O3 nanoparticles, synthesized in the leaf extract of A. indica, can be successfully used for the control of brown rot of sweet oranges.

Green synthesis of copper nanoparticles using Celastrus paniculatus Willd. leaf extract and their photocatalytic and antifungal properties

This research aimed to explore the eco-friendly green synthesis of copper nanoparticles (CuNPs) using Celastrus paniculatus leaves extract. Primarily, the biosynthesized CuNPs characterized by UV–vis spectroscopy showed an absorption peak at 269 nm. Further, The SEM and TEM studies revealed the spherical shape of particles with size ranged between 2−10 nm with an average particle diameter of 5 nm. FT-IR analysis confirmed the presence of functional groups OH, CC and CH triggers the synthesis of CuNPs. The negative zeta potential -22.2 mV indicated the stability of CuNPs was confirmed by DLS and the composition and purity by EDS studies. Further, the photocatalytic property of the CuNPs was divulged by their methylene blue dye degradation potential. The reaction kinetics followed pseudo-first-order with k-values (rate constant) 0.0172 min−1. In addition, this material was found to be a good antifungal agent against plant pathogenic fungi Fusarium oxysporum showed 76.29 ± 1.52 maximum mycelial inhibition.

Utilizing the combined antifungal potential of Trichoderma spp. and organic amendments against dry root rot of mungbean

The present study was carried out to evaluate the effect of bioagents and organic amendments in suppressing the dry root rot of mungbean incited by Rhizoctonia bataticola. The locally isolated pathogen and fungal biocontrol agents were identified based on morphological and molecular characterization. These identified bioagents were tested in vitro, and the highest mycelial inhibition was recorded in dual culture assay by Trichoderma harzianum (74.44%), and among organic amendments, maximum mycelial inhibition was found in neem cake (61.11%). In a greenhouse study, T. harzianum + neem cake effectively enhanced the percent germination (93.33%) and decreased the percent disease mortality (11.67%) than the other treatments. The morphological parameter like plant height (57.50 cm), dry weight (22.83 g) root nodules (51), pods/plant (58), and 100-seed weight (5.78 g) were found to be at the maximum in this combined application. Physiological pigments viz. chlorophyll (2.41 mg/g) and carotenoids (0.19 mg/g), protein content (5.85 mg/g), and leghemoglobin (11.75 mg/g) were also found to be maximum in T. harzianum + neem cake and minimum phenol content (1.41 mg/g). The study concludes that T. harzianum + neem cake can be recommended as an effective approach for the management of dry root rot of mungbean.

Efficacy of organic products against Fusarium oxysporum f. sp. ciceris

Organic formulations viz., cow urine, beejamrit, panchgavya, vermiwash, biosol and composts viz., himcompost, vermicompost, FYM, CPP and NADEP were evaluated against Fusarium oxysporum f. sp. ciceris under in vitro conditions. Among composts, the extracts of CPP (cow pat pit) at 25 per cent concentration yielded maximum mycelial inhibition of 52.2 per cent followed by NADEP with 50.3 per cent. Among organic formulations, extract of cow urine at 10 per cent concentration yielded maximum mycelial inhibition of 72.9 per cent followed by panchgavya with 62.9 per cent. Hence, cow pat pit (CPP) and cow urine at 10 per cent concentrations can be used as soil amendment and seed dresser, respectively for eco-friendly management of Fusarium wilt of chickpea.

Induced Systemic Resistance and Evaluation of Bio-control Agents for Management of Pigeonpea Wilt Caused by Fusarium udum

The performance of the four fungal and two bacterial bioagents were evaluated for the bicontrol efficacy and ability to induce systemic resistance against Fusarium udum causing wilt of pigeonpea which is posing a serious threat to pigeonpea growing regions of India. Among the six isolates, maximum mycelial inhibition was noticed in Trichoderma harzianum (Th- R) as compared to other biocontrol agents. Among contact fungicides, maximum inhibition (> 75 %) of mycelium was recorded in Mancozeb and capton at 0.20 and 0.3 % concentrations. More than 90% inhibition was recorded among the systemic fungicides at all the all the concentrations except thiophanate methyl which recorded 53.67 % inhibition at 0.05 % concentration. Among different treatment combinations of biocontrol agents, the highest vigour index was recorded in P. fluorescense (RP- 46) + P. putida (RP- 56) treated seeds in both the cultivars (Moderately resistant and susceptible). The level of expression of defense related enzymes (PO, PPO & PAL) was more in moderately resistant cultivar(BSMR- 736) rather than susceptible one(ICP- 2376). In glass house experiment seeds treated with P. flourescens (RP- 46) + P. putida (RP-56) recorded least wilt incidence as compared to other treatments. In both Kharif seasons of 2013/14 and 2014/15 recorded significantly lowest wilt incidence and highest yield in soil drenching with 0.2 % Carbendazim fungicide. Among the biocontrol agents, seed treatment @4 g / kg seeds + soil application of PGPR (P. flourescens & P. putida) consortium @ 25kg/ ha in FYM @ 50 kg/ ha, recorded least wilt incidence and highest yield.

Symptomatology of fungal competitors on oyster mushroom’s spawn packets and in vitro evaluation using phytoextracts and a fungicide

An experiment was conducted to find out the fungal competitors and symptom studies in damaged Oyster Mushroom spawn packets at National Mushroom Development and Extension Center, Savar, Dhaka, Bangladesh. A total of nine fungal competitors of oyster mushroom were isolated and identified namely- Trichoderma harzianum Rifai, T. viride Pers. (Green strain), T. viride Pers. (Yellow strain), T. koningii Oudem, Mucor hiemalis Wehmer, Papulaspora byssina Hotson, Neurospora sp. Shear and B.O. Dodge., Aspergillus flavus Link., and Botryodiplodia theobromae Pat. on the basis of microscopic, morphological and cultural characteristics. To produce oyster mushroom in an eco-friendly manner and to find out their antifungal potency, 23 plant species belonging to 19 families were screened out against isolated nine fungal competitors of oyster mushroom. Among 23 extracts, the maximum (44%) mycelial inhibition of T. harzianum was found due to Aegle marmelos whereas Eclipta alba showed the highest mycelial inhibition (62%) of T. viride (Green strain); in case of T. viride (Yellow strain), Cassia tora exhibited the highest mycelial inhibition (39%); Diospyros cordifolia showed the maximum mycelial inhibition (48%) of T. koningii; Curcuma longa (rhizome) gave the maximum mycelial inhibition (90%) of Neurospora sp. There were no significant effects found to control of P. byssina, B. theobromae, M. hiemalis and A. flavus due to 23 different types of botanicals tested. Trichoderma harzianum, T. viride (Green strain), T. viride (Yellow strain), T. koningii, A. flavus, Neurospora sp. and P. byssina was successfully inhibited by 30, 50 and 70 ppm of fungicide-Bavistin 50 WP but B. theobromae and M. hiemalis were not affected by Bavistin at mentioned concentration.Int. J. Agril. Res. Innov. & Tech. 6 (2): 24-30, December, 2016

Integrated Management of Banded Leaf and Sheath Blight of Maize Caused by Rhizoctonia solani f. sp. sasakii

Banded leaf and sheath blight of maize is caused by a destructive and versatile pathogen Rhizoctonia solani f. sp. sasakii. Integrated management of Banded leaf and sheath blight of maize is done by using the bioagents, botanicals and fungicides under both in vitro and in vivo conditions. Under in vitro conditions among the organic enriched compost, vermicompost showed the maximum mycelial inhibition (83.8 %) at 50 % concentration and in case of bioagents, Trichoderma sp. MDA-1 showed the maximum mycelial inhibition up to 87.1 % followed by Trichoderma koningii-DMA-8 (85.7 %). Aqueous extracts of Eucalyptus globules yielded maximum mycelial inhibition of about 92.1 % at 50 % concentration. Crude extract of Eupatorium adenophorum showed 100 % mycelial inhibition at 2.5 % concentration followed by Melia azedarach with 87.8 % inhibition. Among test fungicides, bavistin at 5 ppm was found most effective to inhibit the pathogen up to 77.1 %. Tilt and companion also resulted in the 100 % mycelial inhibition at 100 ppm. Integrated practices i.e. soil amendment with vermicompost and seed treatment with bavistin @ 2.0 g/kg seed followed by 2 foliar sprays of bavistin @ 0.1 % at 15 days interval (T6) was found to be the best treatment with maximum disease reduction of 73.1 % as compared to that of control. Soil amendment with vermicompost and seed treatment with Trichoderma sp. (MDA-1) + Eupatorium adenophorum (50:50) and 2 foliar sprays of bavistin @ 0.1 % at 15 days interval (T7) recorded 53.8 % disease reduction over control.

Antifungal Bioactive Compounds from Chinese Caterpillar Fungus (Ophiocordyceps sinensis (Berk.) G. H. Sung et al.) against Plant Pathogens

Studies were conducted to extract and evaluate the intracellular bioactive molecules of Ophiocordyceps sinensis against plant pathogens. Methanolic fraction of mycelium borne bioactive molecules at 200 L concentration showed the maximum mycelial inhibition of Fusarium oxysporum f. sp. cubense (48.67 per cent) and F. o. f. sp. lycopersici (46.47 per cent), which cause wilt disease in banana and tomato, respectively. GC-MS analysis of methanolic fraction of mycelial mat extract indicated the presence of 14 different compounds hydroxylamine; glycerin; oxime-,methoxy-phenyl; adipamide; 1,2,3-Benzenetriol; cyclododecane; imidazole-5-carboxylic acid; 1,3,5-Benzenetriol; 1,3-Cyclohexanedione, 2-propyl; 2-Propenoic acid, tridecyl ester; n-Decanoic acid; 5-Undecene, 9-methyl; L-Ornithine, N5- (aminocarbonyl) and pyrrolo [1,2-a]pyrazine-1,4-dione, hexahydro. Among these, the compound hydroxylamine identified at 1.817 RT exhibited the maximum peak area of 35.00 per cent. This compound is also known to possess important pharmacological and antimicrobial properties.