Flavus Link Research Articles

Present status, prevalence and seasonal variations of aflaxtoxin in cattle feed, Bihar, India

Background/ Objectives: Aflatoxin B1, a potent carcinogen is produced by Aspergillus flavus Link ex Fries. Natural contamination of aflatoxin in Bihar is fairly high due to socio-economic backwardness and also outdated agricultural and storages practices. Methods/ Statistical analysis: In the present investigation cattle feeds collected in different seasons (Winter, Summer and Monsoon) from three different localities (Bhagalpur, Banka and Naugachia) were screened for aflatoxin B1. Analysis of Variance has been done with the help of Microsoft Excel, 2013 (USA). CD has been calculated at 5%. Findings: The amount of aflatoxin B1 was significantly high (P<0.05%) in household cattle feeds followed by commercial cattle feeds, where the mean value of AFB1 was 5.02 ± 2.46µg/kg and 4.19 ± 1.05µg/kg, respectively. Freshly harvested cattle feeds (maize, paddy husk, paddy straw, maize straw and green grasses) were comparatively safe. Seasons had marked influence on aflatoxin B1 contamination on various types of cattle feeds. Maximum levels of aflatoxin B1 was detected during wet seasons in household cattle feeds (Mean value = 7.79 ± 2.07µg/kg). Maize grains because of high nutritional value and production, it is one of the major ingredients of cattle feeds. In the locality of Naugachia, flood and frequent rains delay the natural drying of maize kernels during harvesting in monsoons resulting thereby, high mould infestation and aflatoxin synthesis. Novelty/ Applications: In order to check the risk of aflatoxin M1 toxin entrance in food chain and subsequent human/ cattle health and economic losses, frequent evaluation of AFB1 in cattle feeds be monitored. Keywords: mycotoxin; aflatoxin B1; cattle feed; seasonal variation; ANOVA test; Bihar

Screening of Cowpea (Vigna unguiculata ( L.)Walp) Varieties for Resistance to Leaf Spot in Southern Guinea Savannah Agro- Ecology of Nigeria

Five cowpea varieties (Vigna unguiculata (L.) Walp) namely UAM 09 1055-6, UAM 09 1051-1, IT 99k-573-1-1, IT 90k-277-2 and IT 99k-573-2-1 were investigated for fungi associated with the seed, leaf spot disease incidence and severity in Makurdi (07o 45’- 7o 50’N and 08o 45’ - 08o 50’E ; 98 m)and Otobi (7°07’ - 7°11'N and 8° 05- 8°10'E) in Benue State, Nigeria under natural infection. The effect ofleaf spot incidence and severity on the growth and yield of cowpea varieties were also evaluated. Fungi associated with the seeds and leaf spot lesions were isolated and identified. Diseased leaf samples from the study locations were found to be infected with Fusarium verticillioides, Curvularia lunata, Aspergillus tamarii Kite, Lasiodiplodia theobromae, Aspergillus flavus Link and Aspergillus niger van Tiegh, Pythium spp, Fusarium solani, Macrophomina phaseolina and Phoma sp. Otobi field had significantly higher incidence and severity of leaf spot disease than the Makurdi field. Cowpea variety IT 99k-573-1-1, IT 99k-573-2-1 and IT 90k-277-2 were classified as moderately resistant in Makurdi with a mean incidence of 22.23%, 16.97% and 16.67% respectively while varieties UAM 09 1051-1 and UAM 09 1055-6 were classified as Moderately susceptible and Highly susceptible with mean leaf spot incidence of 41.67% and 99.17% respectively. In Otobi, all the cowpea varieties screened were classified as Susceptible to leaf spot incidence with the exception of variety IT 90k-277-2 which was classified as moderately susceptible to leaf spot disease.&#x0D; Key words: Cowpea, leaf spot, screening, resistant, susceptible.

Mapping Quantitative Trait Loci Associated With Resistance to Aflatoxin Accumulation in Maize Inbred Mp719.

Aflatoxins are carcinogenic and toxic compounds produced principally by fungal species Aspergillus flavus (Link: Fries) and A. parasiticus (Speare), which are common contaminants of food and feed. Aflatoxins can be found at dangerously high levels and can readily contaminate pre-harvest maize (Zea mays L.) grain. Sources of resistance to aflatoxin accumulation in maize have been identified, however, the highly quantitative nature and complex inheritance of this trait have limited the introgression of aflatoxin accumulation resistance into agronomically desirable lines. Mapping of quantitative trait loci (QTL) was performed on a bi-parental population comprised of 241 F2:3 families derived from the cross of inbred lines Mp705 (susceptible) × Mp719 (resistant). The mapping population was phenotyped in replicated field trials in three environments for resistance to aflatoxin accumulation under artificial inoculation with an A. flavus spore suspension. The genetic linkage map was constructed with 1,276 single nucleotide polymorphism (SNP) and simple sequence repeat (SSR) molecular markers covering a total genetic distance of 1,642 cM across all ten maize chromosomes. Multiple interval mapping revealed that majority of the aflatoxin-reducing alleles and the source for the larger effect QTL identified in this study were contributed from Mp719, the resistant parent. Two QTL identified on chromosome 1 (bin 1.06–1.07) and chromosome 3 (bin 3.09) were the most stable across different environments and when combined, explained 24.6% of the total phenotypic variance across all three environments. Results from the study showed that these chromosomal regions harbor important QTL for influencing aflatoxin accumulation, which is consistent with previous reports with other different mapping populations. These stable QTL were the most promising for controlling aflatoxin accumulation in maize grain. Identifying beneficial alleles derived from Mp719 and closely linked molecular markers through QTL analysis for implementation of MAS could accelerate breeding efforts to reduce aflatoxin accumulation in maize.

Pathogenic potentiality of fungi associated with the seeds of different cotton (Gossypium hirsutum L.) varieties in Bangladesh

A total of 24 species of fungi, namely Aspergillus flavus Link, A. fumigatus Fresenius, A. niger (Type 1 and Type 2) Van Tiegh, A. ochraceus K. Wilhelm, A. nidulans Eidam, Aspergillus sp.1, Aspergillus sp.2, Aspergillus sp.3, Curvularia lunata (Wakker) Boedijn, Colletotrichum gloeosporioides Penz &amp; Sacc, C. gossypii Southw., Chaetomium globosum Kunze., Fusarium nivale (Fr.) Sorauer, F. moniliforme J. Shelden, F. oxysporum Schlechtendal, F. fujikuroi Nirenberg, Mucor sp. P. Micheli ex L., Penicillium sp.1 and sp.2 Link, Rhizoctonia solani Khun., Rhizopus stolonifer (Ehrenb.) Vuill., Rhizomucor sp. Lucet &amp; Costantin, Syncephalastrum racemosum Cohn and Trichoderma viride Pers. were found to be associated with the seeds of 14 varieties (CB 1- CB 14) of cotton. Out of these 24 fungal species, nine were found to be pathogenic to cotton. They were Aspergillus flavus, A. niger (Type 1), Aspergillus sp. 1, Colletotrichum gloeosporioides, Curvularia lunata, Fusarium nivale, F. moniliforme, Mucor sp. and Rhizoctonia solani. These pathogenic fungi had remarkable effect on seed germination, vigor index, root-shoot length and mortality of cotton seedlings. The germination percentage of control seeds was 88 but because of the presence of pathogenic fungi the rate showed considerable reduction in all the varieties and it varied from 20 to 82%. Among the nine fungal isolates Rhizoctonia solani showed maximum reduction in seed germination. Aspergillus flavus, Colletotrichum gloeosporioides and Fusarium moniliforme also caused near about 50% reduction in seed germination. Mortality percentage of control seedling were also less (6) whereas, in inoculated seeds it was higher and varied from 7 - 23%. Root- shoot ratio of control seedlings was high but less in inoculated seedlings. The vigor index of control plant was high (1548.8) but less in inoculated plants. The lowest vigor index was noticed for Rhizoctonia solani (202.0) and highest for Aspergillus sp. 1(1213.6). Results indicated that Curvularia lunata and Rhizoctonia solani showed a greater impact in reduction of cotton seed germination and vigor index.&#x0D; Dhaka Univ. J. Biol. Sci. 29(1): 107-115, 2020 (January)

The comparative virulence of an atoxigenic strain of Aspergillus flavus (Eurotiales: Trichocomaceae) and the commercial ICIPE 69 Metarhizium anisopliae (Hypocreales: Clavicipitaceae) to the bean leaf beetle Ootheca mutabilis (Coleoptera: Chrysomelidae)

The recent isolation of an atoxigenic strain of Aspergillus flavus (Link) (Eurotiales: Trichocomaceae), which was virulent to all stages of Xylosandrus compactus (Eichhoff) (Coleoptera: Curculionidae) has generated interest to investigate virulence of the entomopathogenic fungus against other crop pests, and how it compares with established commercial biopesticides. In this study, we tested the pathogenicity and virulence of the atoxigenic A. flavus strain to Ootheca mutabilis (Sahlberg) (Coleoptera: Chrysomelidae) in the laboratory compared to the commercial Metarhizium anisopliae (Metschnikoff Sorokin) (Hypocreales: Clavicipitaceae; OD®, ICIPE 69). Serial dilutions of both entomopathogenic fungi (1 × 106–1 × 109 conidia/ml) were evaluated against adult O. mutabilis. Distilled water and cypermethrin 5% EC were included as controls. The treatments were replicated four times and the bioassay was repeated once. Both fungi at 1 × 109 conidia/ml killed 100% of tested O. mutabilis within seven days in the 1st and 2nd trials. The concentration of both fungi that killed 50% of O. mutabilis was the same in both trials (5.3 × 106 conidia/ml). The time taken by A. flavus and ICIPE 69 to kill 50% of O. mutabilis was not significantly different in the 1st trial (3.4 ± 0.1 days and 2.9 ± 0.4 days, respectively). However, ICIPE 69 took a significantly shorter time (2.1 ± 0.4 days) than A. flavus (3.6 ± 0.2 days) to kill 50% of O. mutabilis in the 2nd trial. We concluded that A. flavus is comparably as pathogenic and virulent (in terms of cumulative mortality and LC50) against O. mutabilis as ICIPE 69, and therefore both fungi may be viable biopesticides for commercialization against this pest.

Micromycetes-resistant colored cotton is promising material to reduce mycotoxins amounts in textiles

The aim of research was to characterize epiphyte micromycetes observed on variable cotton fibers accessions, to estimate the range of fiber destruction and select cotton, which were the most resistant to fungus damage. The accessions of differently colored Upland Cotton varieties (Gossypium hirsutum L.) evaluated: eleven cotton of natural green, twelve – of brown and eleven of conventional white color. Cotton plants have been grown in Sothern Federal District, RF. The fiber samples for the study were placed into a thermostat in sterile Petri dishes on moistened filter paper in order to stimulate the development of mycelium or sporulation of fungi naturally occurred on fibers. Incubation carried out in a thermostat at a +24-28 °C, humidity of 90-100% and exposed for 28 days. The samples examined with a microscope or binocular magnifier. Aspergillus ustus (Bainier), A. fumigatus Fresen., A. niger v. Tiegh., A. flavus Link, Penicillium aurantiogriseum Dierckx, P. notatum Westling, Rhizopus nigricans Ehrenb. and Alternaria alternata (Fuier) Keissler were detected. Compared with exposed white, accession of green and brown colors were significantly resistant to fungus. The mean of destruction (K) of white cotton varied up to 0.95, but colored accessions not exceeded 0.3 (initial destruction of the surface, not affecting internal fiber’s structure).

Overview of Risk Factors and Strategies for Management of Insect-Derived Ear Injury and Aflatoxin Accumulation for Maize Grown in Subtropical Areas of North America

Abstract Pest and disease risk factors causing maize yield and kernel quality issues in subtropical areas of North America (between 35°N and 23.5°N latitude) are reviewed: preharvest Aspergillus flavus (Link) (Deuteromycetes: Moniliales) infection and propagation in maize ears and ear injury principally caused by Helicoverpa zea (Boddie) and Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae). Risk is affected by potentially interacting factors of maize genetics, ear feeding with insects, fungal inoculum and growth, and weather (rainfall, temperature, and humidity). This review gives special attention to integration of the most efficient pest and disease management strategy combinations and the potential interaction of insect ear feeding and A. flavus occurrence. Management strategies reviewed include maximizing partial genetic resistance to A. flavus and selection of appropriate hybrids for the area, biological control of A. flavus using non-aflatoxigenic strains, avoiding pests and diseases using cultural practices like early planting, and reducing H. zea and S. frugiperda ear injury using Bt transgenes. Understanding the combined influences and identifying combined management approaches may lead to reduced aflatoxin risk and maintaining yield. This review focuses on subtropical areas of North America because the amount of maize produced in warm environments within or similar to subtropical maize production areas is likely to increase due to projected increases in demand for maize and predicted increases in temperature may increase pest and disease risk.

Biological Activity, Apoptotic Induction and Cell Cycle Arrest of New Hydrazonoyl Halides Derivatives.

The hydrazonoyl halides are presently an important target in the field of medicinal chemistry. The interest in the chemistry of hydrazonoyl halides is a consequence of the fact that they undergo a wide variety of reactions which provide routes to a myriad of both heterocyclic and acyclic compounds. In addition, they have diverse biological activities such as antiviral, anthelmintic, antiarthropodal, fungicidal, herbicidal, insecticidal, pesticidal, acaricidal and miticidal Activity correlated to the presence of hydrazonoyl halides. Moreover, many applications in both industrial and pharmaceutical fields have been found to be associated with these halides. Depending on the above facts and continuation to our work, we herein report on the evaluation of the anticancer activity of these two halides prepared according to the published work and trying to know their molecular mechanism that they proceed to stop proliferation and metastasis of tumor cells by molecular tools such as real time PCR using different apoptotic genes, and cell cycle assay. The goal of this present study is to bring attention to the biological activities of hydrazonoyl halides and the molecular pathway they follow to exert their role in apoptotic death of cancer cell. Synthesis of hydrazonoyl halides 2c and 2f. The cytotoxic effect against different human cancer cell lines PC3, HepG-2, HCT-116, MCF-7 and also on normal human cell lines as MCF-10 and MCF-12 in a monolayer culture model was evaluated. Their mechanism of action inside cancer cell was evaluated using different molecular tools. Strong and promising chemotherapeutic hydrazonoyl halides (2a-2f) were evaluated for their different biological activities. As antimicrobial agents, results indicated that three compounds 2a, 2e and 2f exhibited high activity against two tested gram positive bacteria Staphylococcus aureus, Bacillus subtilis, and gram negative ones Escherichia coli, and Pseudomonas aeruginosa, the rest of the compounds were found to be moderately active against the tested microorganisms. Regarding their antifungal effect, compound 2c exhibited potent and promising effect against Candida albicans, while 2b was the most potent toward Aspergillus flavus Link. The compound 2f has repellent effect. With respect to the in vitro antitumor screening, this was done on different human cancer cell lines; namely PC3, HepG-2, HCT-116, MCF-7 and also on normal human cell lines; as MCF-10 and MCF-12 (normal breast epithelial cell and non-tumorigenic breast epithelial cell line) in a monolayer culture model where screening has been conducted at 100μg/ml (single dose test). Single dose test (100μg/ml) showed that, in case of PC3, all compounds have cytotoxic activity over 90% inhibition, 4 compounds have cytotoxic activity with 100% inhibition with Human colon cancer cell line, 4 compounds showed over 90% inhibition with MCF7 cell line and 4 compounds showed cytotoxic activity over 90% inhibition with HepG-2. Results of IC50 values for most promising compounds showed compounds with values lower than 20μM for all tested human cancer cell line. The promising hydrazonoyl halide 2c and 2f were selected for molecular study to know how they could act inside cancer cell causing death. Two biochemical tests were performed using the two halides 2c and 2f to predict their mechanism of action against breast carcinoma. Real time PCR analysis indicates that the two compounds induced the apoptosis of MCF7 cells through the up regulation of caspase-3, BAX mediated P53 mechanism but unfortunately, they promote the expression of anti-apoptotic protein BCL2. Also, cell cycle assay was performed using two different cell lines MCF7 and HCT116 and data revealed that the two compounds 2c and 2f induced apoptotic cells death of both lines via cell growth arrest at G2/M phase. In addition, it was noted that 2c induced arrest in the two lines more efficiently than 2f at G2/M phase.

Antifungal and antiaflatoxigenic activity of rosemary essential oil (Rosmarinus officinalis L.) against Aspergillus flavus

ABSTRACTThe increased risk to health by diverse pathologies, such as cancer, liver diseases, and endocrine alterations, caused by chemical residues in food, has led to the search for sustainable agricultural management alternatives, such as the use of essential oils for the development of natural and eco-friendly fungicides. The aim of this study was to evaluate the antifungal and antiaflatoxigenic activity of Rosmarinus officinalis L. essential oil (REO) against Aspergillus flavus Link. REO was obtained by hydrodistillation and its major components were identified as 1,8-cineole (eucalyptol, 52.2%), camphor (15.2%) and α-pinene (12.4%) by GC/MS and NMR. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) were both 500 µg/mL. REO reduced the mycelial growth of A. flavus at a concentration of 250 µg/mL (15.3%). The results obtained from scanning electron microscopy (SEM) demonstrated a reduction in the size of conidiophores and in the thickness of hyphae in A. flavus caused by treatment with REO (250 µg/mL). The production of ergosterol and the biomass of mycelium were both reduced as the REO treatment concentration increased. The production of aflatoxins B1 and B2 was inhibited after treatment with 250 µg/mL REO, a concentration below the MIC/MFC, indicating that the antiaflatoxigenic effect of REO is independent of its antifungal effect and is likely due to its direct action upon toxin biosynthesis. The data demonstrated that REO may be used as an alternative to synthetic fungicides.

Gamma Irradiation for the Inactivation of Aspergillus flavus Link in Copra (Dried Cocos nucifera L. Meat)

Aspergillus flavus is a known source of aflatoxin and other carcinogens that contaminates perishable goods such as copra, one of the top exports of the Philippines. Fungal contamination in perishable products has caused post-harvest losses and a significant threat to food safety and security. Existing methods to control or prohibit the growth of fungi have been a tedious process proven to be open to subsequent contamination. This study assessed the capability of gamma irradiation in inactivating A. flavus in copra. Locally acquired copra was inoculated with 5.8 × 103 CFU⁄ml of A. flavus’ spores. The contaminated copra was irradiated with varying doses of gamma radiation (0.3, 0.7, 1, 3 kGy). Results showed a decreasing trend in the fungal count as the absorbed doses of gamma irradiation increased. Irradiation of 0.7 kGy achieved a significant reduction of fungal count satisfying regulatory limits. The largest reduction in the fungal count was achieved by 3 kGy with &lt; 1 log CFU⁄ml molds and yeast count (MYC). This study concludes that gamma radiation is effective in inactivating A. flavus.

Deteriorative changes in maize kernels due to Aspergillus flavus Link. and Fusarium verticillioides (Sacc.) Nirenberg

The study aimed at measuring changes in chemical composition of maize kernels due to Aspergillus flavus Link. and Fusarium verticillioides (Sacc.) Nirenberg infection. The samples of maize kernels were incubated at 28 °C for 7, 14, 21, and 28 days. The samples were analysed for mycotoxin, moisture, crude fat, crude protein, crude ash, and crude fibre. Maize kernels inoculated with A. flavus and F. verticillioides exhibited a significant decrease in crude fat. Aflatoxin B1 (AFB1) contamination increased in maize kernels inoculated with A. flavus, and fumonisin B1 (FB1) in kernels inoculated with F. verticillioides. Crude ash and crude fibre content showed no changes. Incubation time significantly affected AFB1 and FB1 contamination levels, moisture, crude fat, and crude protein contents. AFB1 and FB1 contamination were significantly correlated with crude fat degradation. The tested strains had similar deteriorative effects on maize kernels. The significant changes in the proximate composition were only observed in maize kernels with mycotoxin contamination above the regulatory limit of 10 µg kg−1, thus not fit for human consumption.

Tupistra nutans Wall. root extract, rich in phenolics, inhibits microbial growth and α-glucosidase activity, while demonstrating strong antioxidant potential

The current study was performed to determine the phenolic compounds composition, antioxidant and antimicrobial activity, and α-glucosidase inhibitory effect of the root extract of Tupistra nutans Wall., in order to validate its use in traditional medicine. HPLC–MS/MS analysis showed the presence of ferulic acid, protocatechuic acid, p-hydroxybenzoic acid, p-coumaric acid, salicylic acid, chlorogenic acid, caffeic acid, l-phenylalanine as the predominant phenolic compounds. The antioxidant potentials of T. nutans were determined in different solvent extract and found to vary in a concentration-dependent manner. Ethyl acetate-soluble fraction exhibited the highest amount of phenolic acids, flavonoids, antioxidant activity against the DPPH, reduced Fe3+/ferric cyanide complexes to the ferrous form and inhibitory effect on α-glucosidase. Butanol fraction showed the strongest ABTS radical scavenging ability. Methanolic root extract showed higher reduction capability of ferric ions than the other solvent fractions. A significant and higher positive correlation was found between total phenolic content and total flavonoid content with α-glucosidase inhibition and DPPH using ethyl acetate solvent than the other solvent fractions. All the tested microorganisms: Staphylococcus aureus Rosenback (ATCC13150), Salmonella enterica typhimurium Kauffmann and Edwads (ATCC14028), Escherichia coli Castllani and Chalmers (ATCC35150), and fungi: Candida albicans Robin and Berkhout (KTCC7965), Aspergillus fumigatus Fresenius (KTCC6145), A. flavus var. flavus Link ex Fries (KTCC6143), A. niger van Tieghem (KTCC6317) were susceptible to the root extracts at a concentration of 0.12–0.25 mg mL−1. This study may allow us to understand indigenous medicinal values of T. nutans. Furthermore, these results showed that T. nutans is a good source of antioxidants along with antimicrobial and antidiabetic activities and could be used as an important bioresource for the pharmaceutical and food industries.

Relationships between Nutrient Uptake and Nitrogen Fixation with Aflatoxin Contamination in Peanut under Terminal Drought

Terminal drought greatly enhanced Aspergillus flavus Link infection (AI) and aflatoxin contamination (AC) in peanut. Identification of new surrogate traits which have an association with AC may be effective to improve peanut varieties with reduced AI and AC. The objective of this work was to examine the relationships of nutrient uptake and N2-fixation (NF) with AC in peanut in a terminal drought condition. Five peanut varieties were tested in well-watered (WW) and terminal drought (TD) conditions (1/3 available water (AW) from R7 (7th reproductive growth stage; beginning of pod maturity stage)). Data were collected for nutrient uptake (nitrogen, phosphorus, potassium, calcium, magnesium), nodule dry weight (NDW), and NF. AI and AC were also examined. Nutrient uptake, NDW, and NF had negative and significant correlations with AI and AC in the TD condition. Negative and significant correlations of the drought tolerance index of nutrient uptake, NDW, and NF with AI and AC were also observed in the TD condition. The results showed that the ability to maintain nutrient uptake and NF in TD might be a mechanism of tolerance to AI and AC. Moreover, due to their negative impacts on AI and AC, nutrient uptake and NF could be used as selection traits for resistance to AI and AC in peanut in TD.

Phytochemical analysis of Linaria purpurea (L.) Mill. and inhibitory activity on the production of aflatoxin B1 (AFB1) in Aspergillus flavus Link. of one of its metabolites, antirrhinoside

In this work, the first phytochemical study on the total polar fraction of Linaria purpurea (L.) Mill. was performed by means of column chromatography and NMR and MS analysis. Seven compounds were identified i.e. pheophytin a (1), methyl-pheophorbide a (2), linaride (3), antirrhide (4), antirrhinoside (5), linarioside (6) and shikimic acid (7), belonging to three different classes of natural compounds. Compound (2) represents a new compound for the family as well as compound (1) is for the genus and compounds (3, 6, 7) are for the species. The chemosystematic and ethnopharmacological relevance of these results were widely discussed. In addition, compound (5) was tested, for the first time, for its potential antifungal activity, showing to drastically reduce the production of aflatoxin B1 in Aspergillus flavus Link. This further property of compound (5) makes it a potential natural and green anti-aflatoxin B1 agent to be used in the food industry.

In Vitro Antagonism of Trichoderma Verede and Aspergillus Spp. against a Pathogenic Seed Borne Fungus of Sesame

Four soil fungi were isolated from the soil by serial dilution and were identified as Aspergillus flavus Link, A. fumigatus Fresenius, A. niger van Tieghem and Trichoderma viride Pers. The soil fungi were selected to evaluate their antagonistic potential against seed borne fungus Fusarium merismoides isolated from sesame. In dual culture colony interaction Trichoderma viride showed the highest (45.88%) growth inhibiting effect on F. merismoides followed by A. niger (40.00%), A. flavus (36.37) and A. fumigatus (30.77%). Volatile metabolites from T. viride showed the highest growth inhibiting effect on F. merismoides (67.69%) and non-volatile metabolites from T. viride showed the highest growth inhibiting effect on F. merismoides (75.00%).&#x0D; Journal of Bangladesh Academy of Sciences, Vol. 43, No. 1, 17-23, 2019

Antagonistic potential of soil fungi against Colletotrichum gloeosporiodes (Penz.) Sacc., the causal agent of anthracnose of Rauwolfia serpentina (L.) Benth. ex Kurz

Four antagonistic fungi Aspergillus flavus Link, A. fumigatus Fresenius, A. niger van Tiegh. and Trichoderma viride Pers. were isolated from field soil of Rauwolfia serpentina by serial dilution method and selected to evaluate their antagonistic potentiality against Colletotrichum gloeosporiodes (Penz.) Sacc, the causal agent of anthracnose of Rauwolfia serpentina (L.) Benth. ex Kurz following dual culture colony interaction, volatile and non-volatile metabolites. In dual culture method Trichoderma viride showed maximum (84.28%) inhibition of test fungi followed by Aspergillus niger (77.39%), A. fumigatus (43.71%) and A. flavus (29.32%). Volatile metabolites of T. viride showed higher (77.64%) inhibition of test fungi followed by A. flavus (75.58%), A. fumigatus (60.88%) and A. niger (58.23%). Non-volatile metabolites of antagonistic fungi showed that A. flavus showed (94.42%) inhibition of test fungus followed by T. viride (90.90%), A. niger (86.13%) and A. fumigatus (73.73%). Aspergillus flavus, A. niger and T. viride may be exploited commercially as a biocontrol agent against anthracnose disease of R. serpentina.&#x0D; Dhaka Univ. J. Biol. Sci. 28(2): 219-226, 2019 (July)

Identification of quantitative trait loci contributing resistance to aflatoxin accumulation in maize inbred Mp715

Aflatoxin is a mycotoxin produced by the fungus Aspergillus flavus (Link:Fr), an opportunistic ear-rot pathogen of maize (Zea mays L. ssp. mays). Pre-harvest contamination of maize grain with aflatoxin is a chronic problem worldwide and particularly in the Southeastern US. Quantitative trait loci (QTL) were mapped by multiple interval mapping (MIM) in a population consisting of 250 F2:3 lines derived from the cross Mp715 × Va35. Mp715 is resistant to the accumulation of aflatoxin and Va35 is susceptible. The population was genotyped with 1200 single-nucleotide polymorphism (SNP) and simple sequence repeat (SSR) molecular markers and phenotyped for the accumulation of total aflatoxins under artificial inoculation in four environments. Both parents contributed resistance alleles. Two QTL in bins 6.06 and 7.03 were the most promising for the marker-assisted introgression of the resistance present in Mp715. They were the most consistent across individual environments and together were responsible for nearly 30% of the phenotypic variance when data was combined across all four environments. In addition to those two QTL, Mp715 was also the source of the beneficial aflatoxin-reducing allele for several smaller effect QTL. Once their effect is validated in further experiments, the identification of these relatively large effect QTL should facilitate the utilization of this aflatoxin accumulation-resistant germplasm in applied maize breeding programs.

CULTURAL PROPERTIES OF FUNGI OF THE FAMILY MUCORACEAE, THE GENUS ASPERGILLUS AS CAUSATIVE AGENTS OF ZOOANTHROPONOSIS

At present, in Ukraine there is a growing prevalence of fungal infections, including aspergillosis and mucormycosis, against HIV / AIDS, tuberculosis, bronchial asthma and cancerous diseases [11]. The literature available presents scanty data on which of the most commonly used nutrient media provide the highest biosynthetic activity for the fungi of the family Mucoraceae, the genus Aspergillus. The aim of this study was to investigate the cultural properties of the studied isolates of fungi on different nutrient media. The following field fungi isolates were studied: Mucor ramosissimus Samutsevitsch, Rhizopus spp., Aspergillus fumigatus Fresenius, Aspergillus niger van Tieghem, Aspergillus flavus Link. The following nutrient media were used: the Plout medium, the Grigoraki medium, the Czapek agar, the Sabouraud agar, the wort-agar, the Van Eterson medium, the Sabouraud-dextrose broth, the honey medium. The concentration of fungi spores per 1 cm3 of inoculum was assessed on the basis of standard methods using a Goryaev's chamber. The evaluation of the intensity of spore formation on different nutrient media was carried out by standard techniques and assessed in CFU/ cm2 [30]. The most intense growth of micromycetes of the Mucor and Aspergillus genera is found on media containing sucrose, dextrose, maltose, glucose, dextrin, glycerol or plant components (the Sabouraud agar, the Czapek agar, the wort agar, the Grigoraki medium, and the Plout medium).

Microgametophytic selection for identifying maize with resistance to Aspergillus spp. and aflatoxin

ABSTRACTAflatoxin B1, produced by Aspergillus flavus Link ex Fries and A. parasiticus Speare on maize (Zea mays L.), is a potent carcinogen that is linked to liver cancer in animals and humans. Normally, genetic materials are field-inoculated and evaluated by conducting aflatoxin assays in the laboratory to develop host resistance (sporophytic selection). These procedures are costly and time-consuming and limit the amount of genetic material that can be evaluated. Microgametophytic selection (pollen selection) in maize has not been explored for screening genetic material for resistance to Aspergillus spp. and aflatoxin. The objective of this investigation was to examine in vitro pollen germination in the presence of A. flavus and A. parasiticus conidia, and aflatoxin B1 in the F2 generation of a cross between Mp313E (resistant inbred) and SC212M (susceptible inbred). A. flavus conidia significantly inhibited pollen grain germination in comparison with the control and the other two treatments. A. parasiticus and aflatoxin B1 treatments did not differ significantly from each other but differed from the control, suggesting that A. flavus conidia, instead of aflatoxin, could be used for screening germplasm for resistance to Aspergillus and/or aflatoxin. We concluded that pollen grains containing genes for susceptibility to A. flavus can be eliminated in a segregating population and that microgametophytic screening could greatly facilitate recurrent selection and screening of germplasm for resistance to aflatoxin at a much less cost and in a shorter period than field testing. Pollen grains carrying resistance genes can be manipulated to develop recombinant inbred lines to accelerate development of parental inbred lines to produce hybrids possessing tolerance to A. flavus and/or aflatoxin B1.

Evaluation of the aflatoxin contamination and proximate composition of groundnut (&lt;i&gt;Arachis hypogea&lt;/i&gt; L.) infected by &lt;i&gt;Aspergillus&lt;/i&gt; spp.

Aflatoxins B1 concentration and the proximate composition of groundnuts consumed in six Local Government Areas (LGAs) of Benue State in the Southern Guinea Savannah agro- ecological zone of Nigeria were evaluated. Seed health testing was conducted and associated fungi were identified. Aflatoxin B1 (AfB1) produced by Aspergillus flavus were detected and the concentrations quantified using the Enzyme Linked Immunosorbent Assay (ELISA) method. Proximate content of seeds was determined using standard methods of Official Analytical Chemists. Aspergillus flavus Link and Aspergillus niger van Tiegh were the associated fungi found in contaminated groundnut seeds with 15.67 % and 7.67 % occurrence respectively. A combination of both fungi had 4.67 % occurrence. The proximate content of groundnut seed samples ranged from 0.35 % to 40.21 % across the samples analyzed. The proximate analysis indicated that groundnut samples from Agatu LGA had significantly (P 򪪪 0.05) higher protein and fat content of 29.11 % and 40.21 % respectively compared with samples from other LGAs samples. Groundnut samples from Makurdi LGA had significantly (P 򪪪 0.05) higher ash content while samples from Ohimini recorded significantly (P 򪪪 0.05) higher crude fibre. The highest moisture content (9.37 %) was from groundnut seeds from Otukpo LGA. The contamination of the groundnut samples by AfB1 resulted in a significant (P 򪪪 0.05) reduction in the nutritional quality of the groundnut seeds.Keywords: Aflatoxin B1, groundnut, seeds, quality, contamination