Seed-borne Fungi Research Articles

Control of seed born mycobiota associated with Glycine max L. Merr. seeds by a combination of traditional medicinal plants extracts

Seeds from soybean collected from different commercial markets were surveyed for seed-borne fungi. Ninetyeight fungal colonies were isolated all over three monthly isolations constituting twenty-two fungal species. The isolated fungi were belonging to the genera: Alternaria, Aspergillus, Cephalosporium, Chaetomium, Cladosporium, Colletotrichum, Curvularia, Fusarium, Macrophomina, Mucor, Penicillium, Rhizoctonia, Rhizopus, Sclerotium, Stemphylium, and Verticillium. Assay of the antifungal activity of four ethanolic extracts of clove, cinnamon, garlic, and mint was carried out against the most common fungal species (Aspergillus flavus, A. niger, Fusarium solani, F. oxysporium, and F. moniliforme), which significantly reduced the growth of tested fungi. Clove extract recorded the highest antimicrobial potentiality against the seed-borne fungal species, followed by cinnamon, garlic, and mint. Clove and cinnamon achieved minimum inhibitory concentration (MIC) values less than that of the reference antifungal drug fluconazole. Simultaneously, garlic and mint recorded MIC values equal to or higher than that of control. A combination of clove and cinnamon, clove and garlic, cinnamon and garlic, cinnamon, and mint extracts increased the mean relative activity percentage. They decreased MIC values below their values when used individually; this indicated synergistic interaction between the two extracts. A combination of clove with mint and garlic with mint recorded a decrease in the percentage of mean relative activity and an increase in MIC values than their values when used individually, indicating antagonistic interaction between them.

Seed Quality Status of Rice Varieties Based on Physical Properties, Seed Health and Proximate Composition

In the present study, seed quality status of fifteen rice varieties were evaluated for physical properties, health status and proximate composition. Physical properties like moisture content, seed purity, germination and vigor index varied between 11.77-14.67%, 96.08-98.93%, 96.50 to 99.00% and 1972.74 to 2639.76, respectively. The shoot length and root length of seedlings were from 8.93 cm to 12.99 cm and 10.89 cm to 14.22 cm, respectively. Seed health was determined by blotter test method. Five seed-borne fungi were detected and the identified fungi were Bipolaris oryzae (1.00-8.50%.), Fusarium moniliforme (0.50-3.50%), Fusarium oxysporum (0.50-9.00%.), Curvularia lunata (0.00-7.50%) and Alternaria padwickii (0.00-4.00%). Proximate composition analysis assessment was done using Association of Official Analytical Chemists (AOAC) method. The dry matter, ash, crude fiber, crude protein, crude fat and carbohydrate were between 92.52- 93.77%, 2.39-6.70%, 8.65-14.27%, 6.51-9.13%, 1.23-1.97% and 62.84-71.06%, respectively.

Tomato early blight (Alternaria solani): Location and transmission

Tomato is one of the popular vegetable crops grown in India and Tamilnadu. Early blight is the most important disease of tomato caused by Alternaria solani which is seed borne in nature can reduce the seed germination and yield up to 70%. Current study is on the location and transmission of Alternaria solani in tomato seeds. A total of 100 seed samples were collected from seed producers and farmers across Tamilnadu. Seed was extracted from the collected fruits and subjected to various seed health testing methods. Five samples showing higher incidence of seed borne fungi were selected for studying the location and transmission of the pathogen. The results revealed that, Alternaria solani percentage of infection was detected to be higher under Standard Blotter Method (18%). Locality of Alternaria solani ranged up to 35% in seed coat, 48% in cotyledons and 17% in embryonic axis and the field experiments shown 42% seed to seed transmission of the pathogen.

Isolation And Identification of Fungi Associated with Different Species of Stored Graines

This study was conducted on different species of stored grains obtained from Duhok Province, Kurdistan Region, of Iraq to investigate the occurrence of seed borne fungi. Nine types of grains were collected and two methods were selected (agar plate method and blotter method) for fungal isolation. A total of 19 species assigned to 13 genera were identified. The high frequent genera were Aspergillus (4 species), Penicillium, Alternaria and Fusarium (2 species), while other genera include Rhizopus, Cladosporium, Stemphylium, Ulocladium, Humicola, Bipolaris, Curvularia Phoma and Rhizoctonia were represented only in a single species. The results showed a variation in the fungal species and contamination percentage according to the detection and incubation methods. The lowest occurrence percentage was detected in lentils seeds with only one genus represented by Penicillium spp., while the highest occurrence percentage was detected with Chickpea seeds represent by six genera. The most common fungal genera displayed by agar plate method in wheat and chickpea were Rhizoctonia sp. (34.1%) and Penicillium sp. (42.5%) respectively. The highest fungal detection by blotter method was recorded with barley seeds while the lowest was chickpea seeds. The most common fungal genera recorded by blotter method under room temperature after 7 days and 14 days was Penicillium spp, with a percent 100% from chickpea seeds followed by Aspergillus spp with percent of (66.7%, 47.6%) from barley and raisin seeds respectively. While the highest frequent fungus in seeds incubated at 25°C after 7 and 14 days was Aspergillus parasiticus (88.9%) from mash seeds and Rhizopus sp. (80.1%) from lima bean respectively. Blotter method considered an efficient and economically reliable method.

Antifungal Activity of Fruit Extracts of Azadirachta indica on Germination, Infection, Rotten Seeds and Abnormal Rice Seedlings from Chad Republic

Aim: Test the effect of Azadirachta indica fruit extract on seed-borne fungi and seed performance of different rice varieties.
 Study Design: Neem fruits harvested in the locality of Pala in Chad were used to assess the antifungal effect on rice seeds. Samples of eight rice varieties (TOX, CH3, CH8, WITA9 D6, D4, D3 and D1) were collected in Bongor, Chad to assess their performance against the aqueous extract of neem fruits.
 Place and Duration of Study: This study was carried out at the Research Unit of Phytopathology and Agricultural Zoology of the Faculty of Agronomy and Agricultural Sciences of the University of Dschang/Cameroon from June to October 2018.
 Methodology: Rice seeds were dipped in Azadirachta indica extract at concentrations of T25 (25 mg/ml), T50 (50 mg/ml) and T75 (75 mg/ml) for 1 hour before being incubated in petri dishes containing blotting paper. Distilled water (T0) and mancozeb 80 WP (TMn1 mg/ml) were used as negative and positive controls respectively.
 Results: The results showed that the germination rate from rice seeds treated with Azadirachta indica extract was better (97.14%) than the rate from the negative controls (82.53%). The infection rate of rice seedlings, the number of rotten seeds and the number of abnormal seedlings were significantly (P =.05) lower for Azadirachta indica extract treatments than for the negative control (T0).
 Conclusions: Neem (Azadirachta indica) fruit extract has a bio-fungicidal potential and a bio-stimulator of rice seed germination. This extract of Azadirachta indica fruit can be used to improve rice cultivation.

Fungi identification and test on red calliandra (Calliandra calothyrsus) seed as potentially antagonist agent

Red calliandra (Calliandra calothyrsus) is an essential economic plant and used as a renewable energy source. Seed-borne fungi can be beneficial or detrimental. One of the beneficial roles of fungi is as an antagonistic agent. Red calliandra seed is commonly infected by pathogenic fungi such as Fusarium sp., Aspergillus sp., and Rhizopus sp. The purpose of this research was to identify the fungi in red calliandra seeds, which are potential as an antagonistic agent, and to study their ability to inhibit the growth of pathogenic Fusarium sp., Aspergillus sp. and Rhizopus sp. The seeds obtained are from Sukabumi, West Java, Indonesia. Fungi were isolated by soaking the seeds with 1% NaOCl for three minutes then washed with sterile aquadest. It was repeated three times. Furthermore, the seeds were sown on moist paper media and incubated until a fungus colony emerged, which is expected to be a potential antagonistic agent. The result showed that there was one isolate of fungi that was potential as an antagonistic agent; it was Talaromyces sp. It indicates that the antagonistic agent can be isolated from seeds. The inhibition percentages of Talaromyces sp. against Aspergillus sp., Fusarium sp., and Rhizopus sp. at seven days old were 67.92%, 59.4%, 8.89%, respectively. Talaromyces sp. can inhibit the growth of Fusarium sp. Rhizopus sp. and Aspergillus sp. in overgrowth at 14 days old. The antagonistic mechanism of Talaromyces sp. to Aspergillus sp., Fusarium sp. and Rhizopus sp. is microparasitism and competition. Talaromyces sp. isolated from red calliandra seeds were potential as antagonistic agents.

Seed health status and germination of Eucalyptus spp.

The presence of disease causing microorganisms on seeds raises serious quarantine and economic concerns to nurserymen, foresters and seed traders. The agar plate method was used to examine seed-borne mycoflora associated with Eucalyptus seed lots and their effect on seed germination was determined. A total of 35 fungal species from 29 genera were identified from 12 different Eucalyptus species. The Eucalyptus nitens seed lot was the most infested, whereas the lowest incidence of fungi was from the E. dorrigoensis seed lot. Penicillium was the most abundant fungus. Colletotrichum, Aureobasidium and Disculoides were recorded for the first time associated with Eucalyptus seeds. There was a significant reduction in seed germination of seed lots inoculated with selected seed-borne fungi compared to non-inoculated controls. Fusarium oxysporum and F. solani reduced seed germination the most on E. badjensis, E. dorrigoensis, E. nitens, E. pellita, E. teritecomis and E. urophylla seed lots with percentage germination of 31.3 and 33.5; 30.5 and 30.0; 38.8 and 37.0; 30.5 and 32.3; 25.0 and 26.8; 33.3 and 31.8; 31.3 and 33.5%, respectively. Similarly, seed germination was lowest on the E. benthamii seed lot (29.8%) inoculated with C. gloeosporioides, whilst germination of E. grandis, E. smithii and E. viminalis seed lots inoculated with Botrytis sp. and F. solani were 37.0 and 37.5%; 35.8 and 36.3%; 28.3 and 30.0%, respectively. This study has shown that commercial Eucalyptus seed lots carry a wide diversity of fungi and suggests that infested seeds may be a primary reason for poor seed germination.

Seeds infection of Fusarium moniliforme in different Rice varieties grown in mid-hills of Nepal

Fusarium moniliforme is one of the important seed-borne fungi responsible for foot rot disease in rice. The study was conducted at the Plant Pathology Division of NARC, Khumaltar from July- December 2019 to find out the level of seed infection of F. moniliforme in different varieties of rice from mid-hills of Nepal. A total of 20 seed samples of different varieties of rice with 240 seeds of each sample were tested following a deep-freeze blotter method distributing 80 seeds per replication and maintaining 3 replications. Seed to seedling transmission test was carried out under screen house conditions. Two hundred seeds of each highly infected five varieties from laboratory test data were planted in eight pots, twenty-five seeds per pot, and categorized into four replications. Component plating was done to determine the location of F. moniliforme infection in a seed. Data analysis was done using STAR at a 5% level of significance. There was a significant difference among all the varieties. The highest incidence of F. moniliforme infection was found in seeds of Khumal-9 variety and lowest in Fan-10 variety. From seed to seedling transmission test, Khumal-4 variety was found highly susceptible to foot rot among the 5 varieties planted. Transmission percentage of disease from seed to seedling was found ranging from 16.19-72.31%. Equally, Component plating concludes that seed coat, as well as endosperm, was the location of F. moniliforme infection in rice seed. Foot rot being one of the serious diseases of rice at present time researches should be done more on this for its effective management and control. Seed health status testification before taking seeds to the field should be done so that timely control like seed treatment could be applied to control the outbreak of the disease in the field.

Pedigree selection under field conditions within Acala 1517-08 and its glandless derivatives for development of cotton resistant to Fusarium wilt caused by Fusarium oxysporum f. sp. vasinfectum race 4

The soil- and seed-borne fungus, Fusarium oxysporum f. sp. vasinfectum race 4 (FOV4), causes Fusarium wilt in cotton (Gossypium spp.) and represents a significant threat to cotton production in the US. The objectives of this study were to enhance FOV4 resistance in heterogeneous Acala 1517-08 and its derivatives through three cycles of pedigree selection in 2018, 2019 and 2020 under FOV4-infested field conditions. In 2017, in a field not infested with FOV4, 46, 12, and 23 single plants were selected for productivity from a base population of 1100–1400 plants of Acala 1517-08 and its derived glandless lines, Acala 1517-18 GLS and NM 13P1125, respectively. In 2018, the single plant selections, controls and other lines were tested in progeny-rows in an FOV4 infested field for disease responses including mortality rate (MR), root vascular staining (RVS), and disease incidence (DI), resulting in 41, 15, and 26 single plants selected from progenies of the three lines, respectively, based on RVS. These single plant selections were tested in 82 progeny-rows in the same field in 2019, and the second selection cycle based on RVS advanced 40, 16, and 37 plants selected from the progenies of the three lines, respectively, for further evaluation and the third selection cycle in a progeny test in 2020. In 2020, an average of 81–84% plants died in highly susceptible controls, Pima S-7 and Pima DP 744, due to FOV4 infections, while the resistant controls, Pima S-6, Pima PHY 841 RF and NuMex COT 17 GLS, incurred up to 19–24% mortality. As a result of the three cycles of single plant selection, a total of 12 progenies were identified to be as resistant as the resistant controls. On the progeny basis, MR between years was significantly correlated, and MR at different evaluation dates was also significantly correlated with one another and with mean RVS and DI within year. However, due to possible escapes of plants from FOV4 infections, the original RVS scores of individual plant selections were not correlated with their respective progenies; and no significant differences were detected among progeny means grouped based on RVS ratings for single plant selections. The results demonstrate that early plant mortality is a superior means of selecting against FOV4 susceptibility, while using RVS rating late in the season if excluding seedling MR may inflate and distort the resistance level of genotypes, rendering it less reliable in assessing FOV4 resistance in cotton. In addition, many single plants selected for FOV4 resistance with no RVS may be escapes, necessitating repeated progeny tests and selection. The importance of pedigree selection within germplasm, choice of resistant and susceptible checks, FOV4 inoculum density, and the use of RVS, and resistance versus tolerance in response to FOV4 infections under field conditions are discussed in detail.

Diversity of seed borne fungi associated with treated buckwheat (Fagopyrum esculenum Moench) seeds under storage conditions

Present paper deals with occurrence and diversity of fungi on treated seeds of buckwheat (Fagopyrum esculenum Moench) at storage conditions. Study consisted of 20 genotypes of buckwheat and three treatments. The seeds were treated with neem oil @ 5ml per kg (T1) and Carbendezim @2g per kg (T2). Un-treated seeds served as control (T0). Four fungal species, namely Aspergillus spp., Alternaria spp., Rhizopus spp. and Pencilium spp. were found associated with the treated seeds of 20 genotypes. These were the most predominant fungi in terms of prevalence with increase in the storage period. The association of fungi varied with the treatments, genotypes and duration of storage periods. Among 20 genotypes, the association of fungi in buckwheat genotypes was noticed in seven genotypes. The total association of fungi was predominant in G2 genotype when remained un-treated (T0G2) and the rest 13 genotypes showed no traces of fungi. On the other hand, the total fungal association of Aspergillus spp. was highest and Penicillium spp. was lowest.

Fungi Associated With Different Parts of Cotton Seed

Seed samples with highest (CB10), lowest (CB8), moderate fungal frequency (CB3) and randomly selected seeds from all varieties (CB1-14) were used. A total of 14 species of fungi, namely Aspergillus flavus Link, A. fumigatus Fresenius, A. niger Van Tiegh, Curvularia lunata (Wakker) Boedijn, Colletotrichum gloeosporioides Penz & Sacc, Fusarium nivale (Fr.) Sorauer, F. oxysporum Schlechtendal, F. fujikuroi Nirenberg, Penicillium aculeatum Raper & Fennell, Penicillium citrinum Thom, Rhizoctonia solani Khun., Rhizopus stolonifer (Ehrenb.) Vuill., Syncephalastrum racemosum Cohn and Trichoderma viride Pers. were found to be associated with seed parts of different varieties of cotton. The maximum ten species of fungi were isolated from seed coat. The most prevalent fungus was Rhizopus stolonifer which was found in all the parts of all the varieties of cotton seeds examined. Out of the 14 isolated fungi, Aspergillus flavus, A. fumigatus, A. niger, C. lunata, C. gloeosporioides, F. nivale, F. oxysporum, F. fujikuroi, Penicillium aculeatum, R. solani, R. stolonifer, S. racemosum and T. viride were found to be external and Aspergillus flavus, A. fumigatus, A. niger, C. lunata, F. nivale, Penicillium citrinum and R. stolonifer were internal seed borne fungi. Aspergillus flavus, A. fumigatus, A. niger, C. lunata, F. nivale and R. stolonifer were isolated as both external and internal seed borne fungi.
 Dhaka Univ. J. Biol. Sci. 29(2): 237-244, 2020 (July)

Using Multispectral Imaging for Detecting Seed-Borne Fungi in Cowpea

Recent advances in multispectral imaging-based technology have provided useful information on seed health in order to optimize the quality control process. In this study, we verified the efficiency of multispectral imaging (MSI) combined with statistical models to assess the cowpea seed health and differentiate seeds carrying different fungal species. Seeds were artificially inoculated with Fusarium pallidoroseum, Rhizoctonia solani and Aspergillus sp. Multispectral images were acquired at 19 wavelengths (365 to 970 nm) from inoculated seeds and freeze-killed ‘incubated’ seeds. Statistical models based on linear discriminant analysis (LDA) were developed using reflectance, color and texture features of the seed images. Results demonstrated that the LDA-based models were efficient in detecting and identifying different species of fungi in cowpea seeds. The model showed above 92% accuracy before incubation and 99% after incubation, indicating that the MSI technique in combination with statistical models can be a useful tool for evaluating the health status of cowpea seeds. Our findings can be a guide for the development of in-depth studies with more cultivars and fungal species, isolated and in association, for the successful application of MSI in the routine health inspection of cowpea seeds and other important legumes.

Seed-borne pathogenic fungi on some soybean varieties

Abstract. 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.

Constituents Leached by Tomato Seeds Regulate the Behavior of Root-Knot Nematodes and Their Antifungal Effects against Seed-Borne Fungi.

Germinating seeds can release diverse phytochemicals that repel, inhibit, or kill pathogens such as root-knot nematodes and seed-borne fungi. However, little is known about the composition of these phytochemicals and their effects on pathogens. In this study, we demonstrated that tomato seed exudates can attract the nematode Meloidogyne incognita using a dual-choice assay. Eighteen compounds were then isolated and identified from the exudates. Of these, esters (1-3), fatty acids (4-6), and phenolic acids (10-12) were proven to be the signaling molecules that facilitated the host-seeking process of second-stage juveniles (J2s) of nematodes, while alkaloids (17 and 18) disrupted J2s in locating their host. Furthermore, some phenolic acids and alkaloids showed antifungal effects against seed-borne fungi. In particular, ferulic acid (12) showed obvious activity against Aspergillus flavus (minimum inhibitory concentration (MIC), 32 μg/mL), while dihydrocapsaicin (17) showed noticeable activity against Fusarium oxysporum (MIC, 16 μg/mL). Overall, this study presents the first evidence that M. incognita can be attracted to or deterred by various compounds in seed exudates through identification of the structures of the compounds in the exudates and analysis of their effects on nematodes. Furthermore, some antifungal compounds were also found. The findings of this work suggest that seed exudates are new source for finding insights into the development of plant protective substances with nematocidal and antifungal effects.

Efficacy of Sulfuryl Fluoride as a Fumigant against Aspergillus niger on Corn Seeds

The importation of corn seeds may inadvertently introduce seed-borne fungi like Aspergillus niger. One potential method to control this pathogen was fumigation with sulfuryl fluoride. The objectives of this applied research were to obtain effective concentration and exposure time of sulfuryl flouride as a fumigant to control seedborne fungi and to its physiological impact on corn seeds. Aspergillus niger was isolated from corn seed samples, grew it in potato dextrose agar, and used it for in vitro studies. Parameters observed were isolates’ growth inhibition. In vivo studies were conducted using corn seed samples infected by Aspergillus niger. Sulfuryl fluoride was applied at the concentration of 30, 40, 50, and 60 g/m3 and 24, 48, 72, and 96 hour of exposure time. Results showed that sulfuryl fluoride concentration of 40 g/m3 for 48 hours at 26-32°C is the only effective concentration against A. niger in vitro but all of the treatment did not significantly affect A. niger in vivo. Concentration of 30, 40, 50, 60 g/m3 for 24 hours does not affect the quality of the seed.

Identification of seed-borne fungi of farmer-saved seeds of pepper and their control with some selected botanicals

A survey was conducted on the source of planting materials and pre-planting seed treatment practice by pepper farmers in Obenemasi and Ofoase-Kokoben communities in the Ashanti Region of Ghana using a well-structured questionnaire in June, 2011. Seed health test was conducted on 40 farmer-saved pepper seed samples collected from the farmers interviewed using the blotter method in the laboratory. Efficacy of garlic, ginger and neem botanical extracts in managing the seed-borne fungi of pepper seeds was also investigated in this study in-vitro. Results of the questionnaire-based survey indicated that, majority of respondent farmers, about 75% recycled seeds from previous harvest, 20% of respondents also used seeds obtained from friends and 5% obtained their pepper seeds from local markets. Nine genera of fungi including 12 species were identified from the pepper seed samples collected. The three botanical extracts proved effective as Mancozeb in controlling one or more of the test seed-borne fungi. Garlic aqueous extract (60% (w/v)) was effective as Mancozeb in controlling Colletotrichum capsici and Colletotrichum gloesporioides. Ginger aqueous extract (60% (w/v)) was also effective against seed-borne Fusarium and Aspergillus spp. whereas aqueous neem extract (60% (w/v)) was effective in controlling Aspergillus flavus and Aspergillus niger.

Diversity of the Seedborne Fungi and Pathogenicity of Fusarium Species Associated with Intercropped Soybean.

Maize/soybean relay strip intercropping has been widely practiced in Southwest China due to its high productivity and effective application of agricultural resources; however, several seedborne diseases such as seedling blight, pod and seed decay are frequently observed causing severe yield loss and low seed quality. So far, the population and pathogenicity of the seedborne fungi associated with intercropped soybean remain unexplored. In this study, seeds of 12 soybean cultivars screened for intercropping were collected from three growing regions in Sichuan Province of Southwest China, and the seedborne fungi were isolated from the surface-sterilized seeds. Based on sequence analysis of ribosomal DNA internal transcribed spacer (rDNA ITS), 148 isolates were identified into 13 fungal genera, among which Fusarium covered 55.0% as the biggest population followed by Colletotrichum. Furthermore, Fusarium isolates were classified into five distinct species comprising F. fujikuroi, F. proliferatum, F. verticillioides, F. asiaticum and F. incarnatum through sequence analysis of translation elongation factor 1 alpha (EF-1α) and DNA-directed RNA ploymerase II second largest subunit (RPB2). Among them, F. fujikuroi accounted for 51.22% (42/82) and was isolated from 91.7% (11/12) soybean varieties. Pathogenicity assay showed that five Fusarium species were able to infect the seeds of soybean cultivar “Nandou12” and caused water-soaked or rot symptoms, while F. fujikuroi and F. asiaticum had much higher aggressiveness than other species with significant reductions of seed fresh weight and germination percentage. Accordingly, this study indicates that Fusarium species are the dominant seedborne fungi in the intercropped soybean in Sichuan, China, and this provides some useful references for the effective management of seedborne fungal diseases as well as soybean resistance breeding in maize/soybean relay strip intercropping.

Prevalence and Transmission of Seed-borne Fungi of Maize and Their Control by Phenolic Antioxidants

Prevalence and Transmission of Seed-borne Fungi of Maize and Their Control by Phenolic Antioxidants

Antifungal activity of leaf extract against mycotoxin producing fungi

About 90% of the world food crops are being produced by using seeds. Healthy seeds are important for production of healthy crop and these seeds are also responsible for disease transmission. It happens either in field or in post-harvest storage condition. Due to these seed borne fungi, seed get deteriorated which may cause a great economic loss as well as several types of abnormalities occur in seeds. Major storage grain fungi contaminated with mycotoxin, mycotoxins contaminants of fungal origin occurring worldwide and characterized by its acute and chronic toxic effects on human health. In the present attempt were made to study the antifungal activity of leaf extract against mycotoxin producing fungi. Fungi isolated from stored seed grains like cereals, pulses, infected oil seeds were collected from from Marathwada region of Maharashtra, India. Antifungal activity of leaf extract of Calotropis procera, Azadirachta indica, Ocimum sanctum, Withania somnifera and Datura metel were tested against Alternaria alternata, Aspergillus flavus, Aspergillus ochraceus, Fusarium gramineorum and Penicillium citrinum by using 96-well plate method. Leaf extract showed remarkable activity against tested fungi at different concentrations as Minimum Inhibitory Concentration. The leaf extract of Calotropis procera and Azadirachta indica, have good potential antifungal properties against different mycotoxin producing fungi.

Detection of Drechslera avenae (Eidam) Sharif [Helminthosporium avenae (Eidam)] in Black Oat Seeds (Avena strigosa Schreb) Using Multispectral Imaging.

Conventional methods for detecting seed-borne fungi are laborious and time-consuming, requiring specialized analysts for characterization of pathogenic fungi on seed. Multispectral imaging (MSI) combined with machine vision was used as an alternative method to detect Drechslera avenae (Eidam) Sharif [Helminthosporium avenae (Eidam)] in black oat seeds (Avena strigosa Schreb). The seeds were inoculated with Drechslera avenae (D. avenae) and then incubated for 24, 72 and 120 h. Multispectral images of non-infested and infested seeds were acquired at 19 wavelengths within the spectral range of 365 to 970 nm. A classification model based on linear discriminant analysis (LDA) was created using reflectance, color, and texture features of the seed images. The model developed showed high performance of MSI in detecting D. avenae in black oat seeds, particularly using color and texture features from seeds incubated for 120 h, with an accuracy of 0.86 in independent validation. The high precision of the classifier showed that the method using images captured in the Ultraviolet A region (365 nm) could be easily used to classify black oat seeds according to their health status, and results can be achieved more rapidly and effectively compared to conventional methods.