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A serious leaf disease caused by Colletotrichum dematium was found during the cultivation of Sarcandra glabra in Jingxi, Rong’an, and Donglan Counties in Guangxi Province, which inflicted huge losses to plant productivity. Biological control gradually became an effective control method for plant pathogens. Many studies showed that the application of actinomycetes in biological control has been effective. Therefore, it may be of great significance to study the application of actinomycetes on controlling the diseases caused by S. glabra. Strains of antifungal actinomycetes capable of inhibiting C. dematium were identified, isolated and screened from healthy plants tissues and the rhizospheres in soils containing S. glabra. In this study, 15 actinomycetes strains were isolated and among these, strains JT-2F, DT-3F, and JJ-3F, appeared to show antagonistic effects against anthracnose of S. glabra. The strains JT-2F and DT-3F were isolated from soil, while JJ-3F was isolated from plant stems. The antagonism rate of strain JT-2F was 86.75%, which was the highest value among the three strains. Additionally, the JT-2F strain also had the strongest antagonistic activity when the antagonistic activities were tested against seven plant pathogens. Strain JT-2F is able to produce proteases and cellulase to degrade the protein and cellulose components of cell walls of C. dematium, respectively. This results in mycelia damage which leads to inhibition of the growth of C. dematium. Strain JT-2F was identified as Streptomyces tsukiyonensis based on morphological traits and 16S rDNA sequence analysis.

In India, soybean (Glycine max (L.) Merrill) is a significant legume widely accepted due to high protein and oil content and on account of neutraceutical and pharmaceutical values. The investigation was under taken to determine the seed health status of farmers own saved seeds and certified seeds of soybean, associated mycoflora, its impact on seed sowing quality and management of soybean. During the period 150 seed samples obtained form 09 districts spread over 4 agroclimatic regions were analyzed for the associated mycoflora through Standard blotter method and visual observations on Diaphanoscope. The seed association of Macrophomina phaseolina, causal agent of charcoal rot ranged from 3.0 to 15.0% while Colletotrichum dematium, causal agent of anthracnose and pod blight, was in the ranged of 2.0 to 10.0%. The association of Fusarium oxysporum, causal agent of seed root, seedling decay was from 10.0 to 14.0%. The seed rot causing fungi Aspergillus niger (3.0 to 12.0%) Aspergillus flavus (4.0 to 11.0%) were noticed. The purple stain of soybean seed, caused by Cercospora kikuchii was in the ranged of (4.0 to 15.0%) and Soybean mosaic virus infected ranged from (1.0 to 4.0%).

Seed-borne fungi cause several diseases of common bean (Phaseolus vulgaris L.) and soybean (Glycine max L.). The survey of seed-borne fungi of common bean and soybean was carried out on three Egyptian Governorates (Behera, Dakahlia, and Ismailia) in Egypt. Nineteen fungal species comprising therteen genera were isolated from the collected common bean and soybean seed samples, using standard blotter i,e. Alternaria alternata, Alternaria spp., Aspergillus niger, Aspergillus ochraceous, Aspergillus flavus, Botryodiplodia sp., Cladosporium sp., Colletotrichum lindemuthianum, Colletotrichum dematium, Fusarium solani, Fusarium moniliforme, Fusarum oxysporum, Macrophomina phaseolina, Myrothecium sp., Penicillium spp, Rhizoctonia solani, Stemphylium spp., Trichoderma spp. and Trichothecium sp. Pathogenicity tests proved that C. lindemuthianum and C. dematium were pathogenic to common bean and soybean. Polymerase chain reaction (PCR) has many beneficial characteristics that make it highly applicable for detecting Colletotrichum spp. of seeds. PCR diagnosis method and DNA extraction considered one of the most important steps and purity of DNA template for successful PCR assay. For the PCR amplification of C. lindemuthianum and C. dematium, two primers ClF4 and ClF5, stander blotter, agar plate, and deep freezing method were used as seed healthy testing methods. Stander blotter was proved the past and quickly method to detect seed-born of C. lindemuthianum and C. dematium. Trichoderma harzianum reduced linear growth for C. lindemuthianum and C. dematium followed by Trichoderma viride and Bacillus subtilis recording (3.3 cm and 3.9 cm, respectively) followed by Pseudomonas floursence that display a high linear growth (7.4 cm). On the other hand, fungicide Aetro 30% (Iprodione + Tebuconazole) recorded the least linear growth (0.9 cm) for C. lindemuthianum and C. dematium compared with negative control recorded (9.0 cm in diameter). Thymus plant extract caused the lowest liner growth (3.7 cm). Plant extract concentrations caused a significant reduction in the growth of C. lindemuthianum and C. dematium. The highest concentration (1.5 %) gave less fungal growth while the lowest one (0.5%) showed the highest fungal growth compared with negative control.

Colletotrichum species are known as important pathogens of plants with an impact on crop production. Some of these species are also known as a cause of rare ophthalmic infections in humans. A case of keratitis caused by Colletotrichum dematium after corneal trauma in a 56-year-old woman is presented. Infection was diagnosed based on positive microscopy and culture. The fungal isolate was identified by morphological characteristics and DNA sequencing of the ITS rDNA region, β-tubulin (tub2) and glyceraldehyde-3-phosphate dehydrogenase (gapdh) genes. The patient responded well to topical therapy with amphotericin B combined with intravenous amphotericin B but improvement was associated with the corneal collagen cross-linking. The review of the literature revealed another 13 cases of C. dematium keratitis, all but one patient having at least one keratitis risk factor in their history. Almost all patients (n = 12) were treated with topical polyene antibiotics (natamycin or amphotericin B), improvement and cure were achieved in eight of them.

Keratitis is a very serious clinical condition caused by bacteria, fungi or parasites. It is associated with serious complications like blindness or endophthalmitis if remained undiagnosed. A 42-year-old male patient with the history of foreign body inoculation presented with mild pain and redness. After clinical examination, fungal keratitis was diagnosed. Corneal scrapping was sent for microbiological investigation. A very rare fungi Colletotrichum dematium was isolated and identified. Patient was managed with Natamycin tab fluconazole and atropin eye drops. To know the geographical distribution of the rare fungi, more and more cases should be studied and reported, which will help in management of rare fungi and standardisation of therapy.

Soesanto L, Hartono ARR, Mugiastuti E, Widarta H. 2020. Seed-borne pathogenic fungi on some soybean varieties. Biodiversitas 21: 4010-4015. The present study was conducted to detect and identify seed-borne pathogenic fungi in some soybean varieties and their effect on seed germination. Experiment was performed in a completely random design with eight treatments and four replicates. Eight soybean varieties i.e., Malabar, Kaba, Dering, Detam I, Sinabung, Dena, Gepak Kuning, and Slamet were selected for the investigation. Seed borne fungi were isolated using blotter test and agar plate techniques. The variables observed were morphological/cultural characteristics, microscopic features of fungi, and percentage of seed germination. A total of eight fungi namely Aspergillus flavus Link, Aspergillus niger van Tieghem, Cladosporium oxysporum Berk. & M.A. Curtis, Colletotrichum dematium (Pers. et Fr.) Grove f.sp. truncate (Schw.) Arx, Curvularia pallescens Boedijn, Fusarium solani (Mart.) Sacc., Melanospora zamiae Corda, and Nigrospora sp. Mason were isolated from different varieties of soybean seeds. The highest seed germination was found to be 80.5% in Daring and Detam I varieties, respectively, and the lowest 53% was recorded in Dena variety.

In this study, strain KNU17Pc1 was tested for its antifungal activity against Rhizoctonia solani AG-1(IA), which causes banded leaf and sheath blight (BLSB) of maize. KNU17Pc1 was tested further for its broad-spectrum antifungal activity and in vitro plant growth promoting (PGP) traits. In addition, the in vivo effects of KNU17Pc1 on reduction of BLSB severity and seedling growth promotion of two maize cultivars under greenhouse conditions were investigated. On the basis of multilocus sequence analysis (MLSA), KNU17Pc1 was confirmed as P. chlororaphis subsp. aurantiaca. The study revealed that KNU17Pc1 had strong in vitro antifungal activity and was effective toward all in vitro PGP traits except phosphate solubilization. In this study, for the first time, a strain of P. chlororaphis against Colletotrichum dematium, Colletotrichum gloeosporioides, Fusarium oxysporum f.sp. melonis, Fusarium subglutinans and Stemphylium lycopersici has been reported. Further biochemical studies showed that KNU17Pc1 was able to produce both types of phenazine derivatives, PCA and 2-OH-PCA. In addition, solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) analysis identified 13 volatile organic compounds (VOCs) in the TSB culture of KNU17Pc1, 1-undecene being the most abundant volatile. Moreover, for the first time, Octamethylcyclotetrasiloxan (D4), dimethyl disulfide, 2-methyl-1,3-butadiene and 1-undecene were detected in P. chlororaphis. Furthermore, this study reported for the first time the effectiveness of P. chlororaphis to control BLSB of maize. Hence, further studies are necessary to test the effectiveness of KNU17Pc1 under different environmental conditions so that it can be exploited further for biocontrol and plant growth promotion.

In this study, a new species within the genus Colletotrichum was isolated from diseased persimmon leaves collected from Sangju and Cheongdo in the Gyeongbuk province of Korea. The disease was characterized by leaf spots with a brown to gray center surrounded by a black ring with a green halo. Black acervuli with setae and numerous curved conidia were observed on the leaf spots. Phylogenetic analysis based on a combination of multiple loci, including sequences of the internal transcribed spacers, actin, beta-tubulin, chitin synthase-1, and glyceraldehyde-3-phosphate dehydrogenase genes, revealed that the isolates were clearly distinct from other species of the Colletotrichum dematium complex, with the closest species being C. anthrisci. Cultural and morphological characteristics and pathogenicity on persimmon leaves were examined. The isolates differed from C. anthrisci in their cultural and morphological characteristics, such as the conidia and appressoria. Based on molecular phylogenetic, morphological, and cultural characteristics and pathogenicity, this fungus was demonstrated to be a new species, Colletotrichum kakivorum, and the causal agent of a leaf spot disease on persimmon in Korea.

Endophytic bacteria hold tremendous potential for use as biocontrol agents. Our study aimed to investigate the biocontrol activity of Pseudomonas fluorescens BRZ63, a new endophyte of oilseed rape (Brassica napus L.) against Rhizoctonia solani W70, Colletotrichum dematium K, Sclerotinia sclerotiorum K2291, and Fusarium avenaceum. In addition, features crucial for biocontrol, plant growth promotion, and colonization were assessed and linked with the genome sequences. The in vitro tests showed that BRZ63 significantly inhibited the mycelium growth of all tested pathogens and stimulated germination and growth of oilseed rape seedlings treated with fungal pathogens. The BRZ63 strain can benefit plants by producing biosurfactants, siderophores, indole-3-acetic acid (IAA), 1-aminocyclopropane-1-carboxylate (ACC) deaminase, and ammonia as well as phosphate solubilization. The abilities of exopolysaccharide production, autoaggregation, and biofilm formation additionally underline its potential to plant colonization and hence biocontrol. The effective colonization properties of the BRZ63 strain were confirmed by microscopy observations of EGFP-expressing cells colonizing the root surface and epidermal cells of Arabidopsis thaliana Col-0. Genome mining identified many genes related to the biocontrol process, such as transporters, siderophores, and other secondary metabolites. All analyses revealed that the BRZ63 strain is an excellent endophytic candidate for biocontrol of various plant pathogens and plant growth promotion.

A serious leaf disease caused by Colletotrichum dematium was found during the cultivation of Sarcandra glabra in Jingxi, Rong’an, and Donglan Counties in Guangxi Province, which inflicted huge losses to plant productivity. Biological control gradually became an effective control method for plant pathogens. Many studies showed that the application of actinomycetes in biological control has been effective. Therefore, it may be of great significance to study the application of actinomycetes on controlling the diseases caused by S. glabra. Strains of antifungal actinomycetes capable of inhibiting C. dematium were identified, isolated and screened from healthy plants tissues and the rhizospheres in soils containing S. glabra. In this study, 15 actinomycetes strains were isolated and among these, strains JT-2F, DT-3F, and JJ-3F, appeared to show antagonistic effects against anthracnose of S. glabra. The strains JT-2F and DT-3F were isolated from soil, while JJ-3F was isolated from plant stems. The antagonism rate of strain JT-2F was 86.75%, which was the highest value among the three strains. Additionally, the JT-2F strain also had the strongest antagonistic activity when the antagonistic activities were tested against seven plant pathogens. Strain JT-2F is able to produce proteases and cellulase to degrade the protein and cellulose components of cell walls of C. dematium, respectively. This results in mycelia damage which leads to inhibition of the growth of C. dematium. Strain JT-2F was identified as Streptomyces tsukiyonensis based on morphological traits and 16S rDNA sequence analysis.

During surveys of cowpea (Vigna unguiculata (L.) Walp.) fields in the Gauteng province, a destructive stem disease was observed. Stem symptoms began as tan brown discolorations that later spread, becoming dark purplish-brown. Sunken, necrotic lesions and small, black acervuli also were visible on the stems. Colletotrichum dematium (Pers.) Grove was consistently isolated from diseased material. Pathogenicity of an isolate of C. dematium from cowpea stems (deposited with the National Collection of Fungi, South Africa, designated PPRI 6121) was confirmed by inoculating stems of 20 cowpea seedlings with a 105 conidia per ml suspension. Inoculated plants were maintained in humidity chambers for 48 h and then returned to the greenhouse. After 7 days, symptoms resembling those observed in the field were apparent. C. dematium was reisolated from these plants and produced cultures identical to those of the original isolate. This is the first report of C. dematium on cowpea in South Africa.

Overwinter survival of Colletotrichum dematium, the causal agent of mulberry anthracnose, was examined in Japan. Conidia and infected mulberry leaves were mixed with soil and placed on the ground in early December. Viability of conidia declined rapidly under field conditions—they could not be recovered within 30 days—whereas conidia placed indoors or outdoors under a roof protected from rain and snow survived longer. When a suspension of soil infested with conidia was used to inoculate detached healthy leaves, no infection was detected after 65 days of incubation, suggesting that conidia in soil are not a significant form of overwintering inoculum. When infected or latently infected leaves incubated in soil under field conditions were used as inoculum on leaves, it was shown that the fungus remained viable for at least 150 days. The fungus in infected leaves maintained under laboratory conditions at different temperatures survived for at least 90 days at 25 and 35°C and for 600 days at 0°C. These results suggest that C. dematium can overwinter in infected or latently infected leaves, and that these leaves can be a source of primary inoculum the following year. Hence, the elimination of fallen leaves in the field in autumn may be an effective way to prevent occurrence of the disease the following year.

Anthracnose of tomato (Lycopersicon esculentum Mill. var. pyriforme (Dunal) L.H. Bailey) was observed on ripe fruits of pear-shaped tomato in the postharvest phase during September 1998 to February 1999. Anthracnose causes a rot of ripe fruit that can cause significant losses in the field and during storage. Symptoms occurred on fruits of several cultivars grown in commercial fields at La Plata, Buenos Aires Province, Argentina. Fruit rot began as small, round (1 to 2 mm diameter), grayish, sunken, watersoaked lesions. The center of the spots became tan and flecked with small black specks. Individual spots enlarged concentrically to approximately 2 cm in diameter and became covered with numerous, submerged, black acervuli that formed in concentric rings and, under wet conditions, produced a mass of slimy salmon-colored spores. In time, total fruit rot often occurred due to coalescence of multiple lesions. Symptoms developed during storage, resulting in diminished fruit quality and marketable value. Colletotrichum dematium (Pers.) Grove was isolated consistently by plating surface-disinfected lesion margins on acidified potato dextrose agar (PDA). Colonies on PDA were gray, olivaceous to black, with abundant acervuli. Conidia were one-celled, hyaline, and falcate, with acute apices measuring 17 to 28 × 2 to 4 μm, consistent with the description of C. dematium (1). Acervuli were superficial, black, and setose. A fungal isolate was selected to complete Koch's postulates. Surface-disinfected ripe fruits of tomato cvs. Perita and Larga Vida were punctured with a sterile needle containing conidia from sporulating cultures. Inoculated fruits were incubated at 25°C for 48 h in a moist chamber. After 3 to 5 days, soft, watery spots developed at the inoculation point on the fruit, and C. dematium was reisolated from the lesions. Fruits that were punctured but not inoculated did not develop symptoms or yield C. dematium. To confirm pathogenicity on leaves, disease-free tomato plants were sprayed with a conidial suspension (2 × 105 spores per ml) of the pathogen. Control plants were sprayed with sterile water. Inoculated plants and controls were left bagged for 48 h and placed in a greenhouse at 20 to 25°C. After 1 week, necrotic leaf spots developed on inoculated plants. Leaf spots were small, circular, and brown. Yellow rings often surrounded the spots. C. dematium was reisolated from lesions on these leaves. This is the first report of C. dematium on tomato in Argentina. Reference: (1) B. C. Sutton. 1980. The Coelomycetes: Fungi Imperfecti with Pycnidia, Acervuli and Stromata. Commonwealth Mycological Institute, Kew, England.

Polygonatum odoratum (Mill.) Druce (Angular Solomon's seal) is a well-known ornamental plant and herbal drug, which is used in traditional medicine. Severe leaf spots were observed in wild Angular Solomon's seal plants in a public park in Trento, Italy. A combination of morphological and molecular characteristics, including sequence data of ITS-rDNA, large subunit (LSU), beta tubulin (TUB) and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) led to identification of two species, namely Phoma odoratissimi and Colletotrichum dematium s. str., isolated from these leaf spots. Pathogenicity of the isolates was confirmed on wounded leaves of Po. odoratum; indeed, both species induced leaf spot symptoms on inoculated leaves within 10 days of inoculation. This is the first report of leaf spot disease caused by Ph. odoratissimi and C. dematium s. str. on Po. odoratum, which can be considered a new host for both the species examined in this study. In addition, isolation of Ph. odoratissimi represents a new record for the mycobiota of Italy.

Effect of mehogoni, mehedi and allamanda extracts were tested to control seed borne fungi of okra seeds collected from 6 companies of notunbazar in Mymensingh district. Prevalence of seed borne fungi was studied by blotter method in the Seed Pathology Center (SPC) and MS Laboratory, Department of Plant Pathology, Bangladesh Agricultural University (BAU), Mymensingh. The highest germination percentage was recorded from ACI seeds (88%), while lowest (70%) in BADC seeds. Six predominant fungal genera were identified. These species were Fusarium oxysporum (5.08%), Aspergillus flavus (4.50%), Aspergillus niger (6.50%), Colletotrichum dematium (4.67%), Rhizopus stolonifer (3.33%) and Penicillium spp. (3.00%). Germination percentage and fungal association varied from company to company. The germination was ranged from 70-95% and infections were recorded 0.80-6.1% in all the treated seeds. Mehogoni extracts at the rate of 1:1 showed best performance in increasing seed germination (96.00%) next to allamanda (70%). Vigour index of okra seeds were increased 19.14% over untreated seeds by the treatment of mehogoni seed extracts at the rate of 1:1. Mehogoniseed extract at the rate of 1:1 seemed to be adoptable at the farmer?s level as an organic management practice.Asian J. Med. Biol. Res. December 2015, 1(3): 628-640

Severe anthracnose symptom was recorded on the leaves of five angiosperms during September to November, 2010. In total nine species of fungi belonging to four genera of the class deuteromycetes and a sterile fungus were found to be associated with the infected leaves of Abelmoschus esculentus (L.) Moench, Cucurbita maxima Duchesne, Datura metel L., Gossypium hirsutum L. and Vigna sinensis L. The associated fungi were Aspergillus flvaus Link , A. fumigatus Fresenius, A. nidulans (Eidam) G. Winter, A. niger van Tiegh, Cercospora sp., Colletotrichum capsici (Syd.) Butler & Bisby, Colletotrichum dematium (Pers.) Grove, Colletotricum gloeosporioides (Penz.) Penz. and Sacc . , Curvularia clavata Jain, and a sterile fungus. Bangladesh J. Sci. Res. 28(2): 103-111, Dec-2015

Silicon (Si) has proven to be effective in controlling diseases in many crops and can be used as a substitute of fungicides. It has been shown that rice hull could be applied to the soil as a non-hazardous silicon rich source in crop production. This study was conducted to investigate the effect of half burnt rice hull (HBRH) as a silicon source in suppression of anthracnose in tomato and understanding underlying mechanisms of disease resistance. HBRH was made by burning raw rice hull at 250 °C for 15 minutes. Six different levels of HBRH: 0, 5, 10, 15, 20 and 25 g per 1 kg of soil were incorporated into soil along with Department of Agriculture (DOA) recommended levels of NPK fertilizers. The resistance against anthracnose disease was evaluated by measuring the lesion area of tomato fruits followed by the challenged inoculation with Colletotrichum dematium for 10 days after inoculation. The mechanism behind Si induced resistance was studied by measuring the fruit firmness and cuticle thickness (CT). A significant reduction (at P ≤ 0.05) of anthracnose disease (87 and 77%) was observed in inoculated fruits of 25 and 20 g HBRH per 1 kg of soil treatments. Onset of the disease was delayed by 4 and 3 days after inoculation in fruits obtained from 25 and 20 g HBRH treated plants compared to the control. The increase of fruit firmness and CT were significant in 25 and 20 g HBRH per 1 kg of soil provided fruits. Consequently, these results suggest that HBRH is a Si rich source and 20 g HBRH per 1 kg soil would be sufficient in suppressing tomato anthracnose caused by C. dematium and the resistance might have triggered with silicon induced thicken cuticle and increased fruit firmness.

Fungal diseases of cotton plant ( Gossypium hirsutum L.) were studied during July, 2011 to June, 2012. Eleven cotton varieties were selected for the experiment. Alternaria alternata (Fr . ) Keissler, Aspergillus niger van Tiegh, Colletotrichum gossypii Sowthworth, Colletotrichum dematium (Pers.) Grove, Curvularia clavata Jain, Fusarium sp., Gleotrichum sp., Hyalopycnis sp., Pestalotiopsis guepinii (Desm.) Stay, and a sterile fungus were isolated from infected leaves of cotton varieties CB6 and CB11. Colletotrichum gossypii was isolated from both the varieties and C. dematium was exclusively isolated from CB6. Varieties CB6 and CB11 were more susceptible than other varieties. Cotton varieties CB1, CB2, and CB3 showed negligible infection on leaves and bolls. Colletotrichum gossypii and Hyalopycnis sp. are new record for Bangladesh. Moreover, association of C. dematium, Gleotrichum sp. , P. guepinii and Hyalopycnis sp. with cotton is being reported first time. The three fungi Colletotrichum. gossypii, C. dematium and Hyalopycnis sp. are described and illustrated in this account as new Deuteromycetous records for Bangladesh. Journal of Bangladesh Academy of Sciences, Vol. 39, No. 2, 213-221, 2015

Fungi have long been identified as causal agents of plant diseases. The development of plant antifungal activity was attempted by synthesis of a new type of anionic and nonionic surfactant. The surface properties were studied, including critical micelle concentration (CMC), effectiveness (πcmc), maximum surface excess (Γmax), and minimum surface area (Amin). Free energy of micellization and adsorption was calculated (ΔG°mic and ΔG°ads). The antifungal activity of the prepared surfactants was verified in vitro by the poisoned food technique against eight phytopathogenic fungi: Colletotrichum dematium, Drechslera hawaiiensis, Fusarium oxysporum, Fusarium solani, Humicola fuscoatra, Pestalotia laurocerasi, Phoma spp., and Phytophthra. The results reported that the percentage inhibition of mycelial growth increases with increasing concentrations of the surfactant for all fungal species used. These results indicated that the surfactant inhibited the mycelial growth of all fungal species in a dose-dependent manner. Blend surfactants have a potential antifungal effect for the control of some phytopathogenic fungi.

Calotropis procera has many important medicinal properties with proven pharmacological potential. Some of these properties may be mediated by its fungal endophytes. This study analyzed, for the first time, the community of endophytic fungi of C. procera outside its region of origin. A total of 156 fungal isolates distributed across 19 taxa were obtained from 468 fragments of C. procera leaves at different stages of maturation. The rate of endophyte colonization increased with the leaf age/development. The dominant species of endophytic fungi of C. procera introduced in Northeast Brazil were different from those found in studies on the same species and other species of the same genus in native regions. The dominant endophyte was Phaeoramularia calotropidis (63.5 %), followed by Guignardia bidwellii (21.1 %). Six isolates of endophytic fungi showed antimicrobial activity against human pathogenic micro-organisms and one plant pathogenic fungus. The antibacterial activity was more intense than the antifungal activity. The endophytic Curvularia pallescens (URM 6048) stood out inhibited Gram-positive bacteria, Staphylococcus aureus, Streptococcus pyogenes, the plant pathogenic fungus Colletotrichum dematium. Ecological and biotechnological aspects of endophytic mycota are discussed.

An experiment was conducted using farmer’s okra (Abelmoschus esculentus L. Moench) seeds in Seed Pathology Centre, Bangladesh Agricultural University, Mymensingh to determine the efficacy of plant extracts (garlic, allmanda, neem, ginger and biskathali extracts) and vigour index of seedling for controlling the seed-borne fungal diseases of okra. In the laboratory experiment, the prevalence of seed-borne fungi associated with farmer’s okra seed investigated by blotter method. The identified fungi species in the collected seeds were Colletotrichum dematium, Macrophomina phaseolina, Fusarium oxysporum, Aspergillus flavus, Aspergillus niger, Penicillium spp. and Rhizopus spp. The test seed materials were treated with garlic tablet, allmanda tablet @ 1:1 and 2:1 w/v and neem extract, ginger extract and biskathali extract @ 1:1 and 1:2 w/v for each to control pathogens with control treatment. The significantly highest germination (62.5%) and lowest incidence of pathogen (5.25%) were recorded in garlic tablet @ 2:1 w/v treated seeds. The okra seeds treated by garlic tablet @ 2:1 w/v was also showed the higher vigour index (545.60%) compare to untreated seed (423.40%).DOI: http://dx.doi.org/10.3329/jesnr.v7i2.22212 J. Environ. Sci. & Natural Resources, 7(2): 85-88 2014