Mycoflora and Potential for Mycotoxin Production of Freshly Harvested Black Bean from the Argentinean Main Production Area

A mycological survey was carried out, for the first time, on black bean samples from the northwestern Argentinean province of Salta in the 1999 harvest season. Ten varieties of black beans were evaluated at three locations. Species of the genus Alternaria were the most prevalent component of the black bean mycoflora. Species of Fusarium, Sclerotinia, Rhizoctonia and Acremonium were also recorded. The predominant species of the genera isolated were Alternaria alternata, Sclerotinia sclerotiorum, Rhizoctonia solani, Fusarium semitectum and Acremonium strictum. An analysis of variance was applied to determine possible differences between black bean varieties. Variety FT88/519 was the most susceptible to Sclerotinia sclerotinia infection, while the variety DOR 604 was the least susceptible. As toxigenic species were recovered, Alternaria toxins, zearalenone and trichothecenes may pose a contamination risk for black bean.     

Fusarium species from nepalese rice and production of mycotoxins and gibberellic acid by selected species

Infection of cereal grains with Fusarium species can cause contamination with mycotoxins that affect human and animal health. To determine the potential for mycotoxin contamination, we isolated Fusarium species from samples of rice seeds that were collected in 1997 on farms in the foothills of the Nepal Himalaya. The predominant Fusarium species in surface-disinfested seeds with husks were species of the Gibberella fujikuroi complex, including G. fujikuroi mating population A (anamorph, Fusarium verticillioides), G. fujikuroi mating population C (anamorph, Fusarium fujikuroi), and G. fujikuroi mating population D (anamorph, Fusarium proliferatum). The widespread occurrence of mating population D suggests that its role in the complex symptoms of bakanae disease of rice may be significant. Other common species were Gibberella zeae (anamorph, Fusarium graminearum) and Fusarium semitectum, with Fusarium acuminatum, Fusarium anguioides, Fusarium avenaceum, Fusarium chlamydosporum, Fusarium equiseti, and Fusarium oxysporum occasionally present. Strains of mating population C produced beauvericin, moniliformin, and gibberellic acid, but little or no fumonisin, whereas strains of mating population D produced beauvericin, fumonisin, and, usually, moniliformin, but no gibberellic acid. Some strains of G. zeae produced the 8-ketotrichothecene nivalenol, whereas others produced deoxynivalenol. Despite the occurrence of fumonisin-producing strains of mating population D, and of 8-ketotrichothecene-producing strains of G. zeae, Nepalese rice showed no detectable contamination with these mycotoxins. Effective traditional practices for grain drying and storage may prevent contamination of Nepalese rice with Fusarium mycotoxins.     

浙江省仓贮稻谷大米真菌区系的研究

在浙江省采集仓贮稻谷及大米样品,共分离到真菌17属48种(不包括酵母菌)。其中:曲霉属(Aspergillus)18种,青霉属(Penicillium)10种,镰孢霉属(Eusarium)4种。研究表明:在浙江省地区之间,贮粮真菌种类无明显差异。稻谷加工成大米后,籽粒表面带菌量及内部带菌率均明显下降,其真菌区系以贮藏真菌为主。稻谷在贮藏前以田间真菌为主。贮藏1—4个月的稻谷因贮藏真菌的种类、数量明显增长,而田间真菌的种类和数量仍保持在较高的水平上,其表面带菌量及谷粒带菌率处于高峰期;贮藏1年以上的稻谷,其主要带菌种类为贮藏真菌,带菌量及带菌率明显下降。早籼谷和晚粳谷在相同贮藏条件下其带菌种类和数量基本一致。     

Fusarium Species from Nepalese Rice and Production of Mycotoxins and Gibberellic Acid by Selected Species

Infection of cereal grains with Fusarium species can cause contamination with mycotoxins that affect human and animal health. To determine the potential for mycotoxin contamination, we isolated Fusarium species from samples of rice seeds that were collected in 1997 on farms in the foothills of the Nepal Himalaya. The predominant Fusarium species in surface-disinfested seeds with husks were species of the Gibberella fujikuroi complex, including G. fujikuroi mating population A (anamorph, Fusarium verticillioides), G. fujikuroi mating population C (anamorph, Fusarium fujikuroi), and G. fujikuroi mating population D (anamorph, Fusarium proliferatum). The widespread occurrence of mating population D suggests that its role in the complex symptoms of bakanae disease of rice may be significant. Other common species were Gibberella zeae (anamorph, Fusarium graminearum) and Fusarium semitectum, with Fusarium acuminatum, Fusarium anguioides, Fusarium avenaceum, Fusarium chlamydosporum, Fusarium equiseti, and Fusarium oxysporum occasionally present. Strains of mating population C produced beauvericin, moniliformin, and gibberellic acid, but little or no fumonisin, whereas strains of mating population D produced beauvericin, fumonisin, and, usually, moniliformin, but no gibberellic acid. Some strains of G. zeae produced the 8-ketotrichothecene nivalenol, whereas others produced deoxynivalenol. Despite the occurrence of fumonisin-producing strains of mating population D, and of 8-ketotrichothecene-producing strains of G. zeae, Nepalese rice showed no detectable contamination with these mycotoxins. Effective traditional practices for grain drying and storage may prevent contamination of Nepalese rice with Fusarium mycotoxins.     

Monitoring of level of mean concentration and toxicity equivalence (TEQ) of polychlorinated biphenyls (PCBs) in selected vegetables,beans and grains in khanewal and multan,Pakistan

Contamination of food chain by Polychlorinated biphenyls through use of pesticides, electric and industrial waste poses human health risk. In previous studies, PCB species were stated as endocrine disrupting pollutants and showed toxic health effects like cancerous and noncancerous in animals. The aim of this study was to investigate the levels of PCBs and its toxicity equivalence in food item from plant source to evaluate the health risk in Khanewal and Multan, Pakistan. Samples were collected and processed for further analysis of PCB species through GC/MS after extraction and clean up. The mean concentrations of PCBs ranged as 2.71–151.67 ng/g in beans and grains and 2.30–97.00 ng/g dry weight in vegetables and were lower than 200–3000 ng/g PCBs recommended by FDA tolerance level for all foods. The mean concentrations of two NDL-PCB species detected in all vegetables, beans and grains except S.indicum and T.aestivum were lower than maximum allowable concentration of non-dioxin like PCBs i.e. 40ngg^?1 reported by European Commission. Mean TEQ of sum of 14 PCB species ranged as 1.52–5.91 ng-WHO-TEQg^?1 in vegetables and 1.46–10.04 ng-WHO-TEQg^?1 in beans and grains. The present study concluded that the mean concentrations and mean TEQs of PCB species in most of the vegetables, beans and grains were found safe but due to higher consumption rate of some vegetables and grains, posed the moderate level of risk for human health. This study emphasizes on an implement of the strict rules regarding the use of restricted chemicals to diminish the effluence in food chains. Current research will be useful in up gradation of effective measures to reduce the poisonous contribution of PCB sources and the sustainability of terrestrial ecosystem in the country.     

Distribution of Zearalenone-Producing Fusarium Species in Japan

One hundred sixty-six isolates of Fusarium spp. from domestic cereal grains, feed, and other sources were examined for their ability to produce zearalenone on autoclaved moist rice grains. They belonged to the following species (number of producers/number tested): F. roseum (9/28), F. roseum (Culmorum) (3/4), F. roseum (Gibbosum) (2/5), F. roseum (Avenaceum) (1/2), F. roseum (Scirpi) (0/1), F. tricinctum (1/4), F. tricinctum (Sporotrichiella) (0/7), F. lateritium (1/1), F. episphaeria (0/2), F. moniliforme (0/3), F. oxysporum (0/12), F. rigidiusculum (0/4), F. solani (0/4), F. splendens (0/1), F. nivale (0/2), and Fusarium spp. (15/86). Zearalenone was isolated from molded rice by ethanol extraction and purified by column chromatography. Selected isolates of F. roseum M-3-2 and F. roseum (Gibbosum) A-O-2 produced 50 to 100 mg of zearalenone per kg of rice. Increased yields (250 to 407 mg/kg of rice) were obtained by F. roseum M-3-2 when the substrate was supplemented with 1% peptone.     

Mycotoxin-Producing Potential of Mold Flora of Dried Beans

To evaluate the potential for mycotoxin production by molds in dried beans, the mold flora of 114 samples was determined both before and after surface disinfection of the beans with 5% NaOCl. Surface disinfection substantially reduced mold incidence, indicating that contamination was mainly on the surface. The flora, both before and after disinfection, was dominated by species of the Aspergillus glaucus group, the toxicogenic species A ochracues, Penicillium cyclopium, and P. viridicatum, and species of Alternaria, Cladosporium, and Fusarium. The toxicogenic species Aspergillus flavis, A. versicolor, Penicillium Citrinum, P. expansum, P. islandicum, and P. urticae were encountered less frequently. Of 209 species of Aspergillus and Penicillium screened for mycotoxin production on sterile rice substrate, 114 produced one or more of the following mycotoxins: A. flavus, aflatoxins; A. ochraceus, ochratoxins; A. nidulans, A. unguis, and A. versicolor, sterigmatocystin; P. cyclopium, penicillic acid; P. citrinum and P. viridicatum, citrinin; P. urticae, patulin and griseofulvin. Sterigmatocystin production by A. unguis is reported for the first time.     

Characterization of resistance to three bruchid species (Callosobruchus spp., Coleoptera,Bruchidae) in cultivated rice bean (Vigna umbellata)

Resistance of wild and cultivated rice bean (Vigna umbellata [Thunberg] Ohwi and Ohashi) to three bruchid species, Callosobruchus chinensis L., Callosobruchus maculatus F., and Callosobruchus analis F., was evaluated. All but three accessions of cultivated, and all wild rice bean accessions tested, exhibited complete resistance to all three bruchid species. Rice bean seeds with seed coat removed also showed complete resistance to the three bruchid species. Results indicate that physical attributes and/or chemical(s) present in the seed coat of rice bean are not the main factors responsible for resistance. Feeding tests were performed by using artificial beans prepared with varying proportions of rice bean (resistant) and azuki bean (susceptible) flour. Number of bruchid adults that emerged decreased, and larval developmental period (days) was extended, when artificial beans with an increasing proportion of rice bean flour were used. These tests revealed that a chemical compound(s) contained in the cotyledon of rice bean has an inhibitory effect on the growth of these bruchid species. The results also indicate that the chemical(s) in rice bean cotyledon is most effective against C. maculatus.     

栽培稻与其野生近缘种的可交配性研究

通过人工授粉方法研究栽培稻与二倍体和四倍体野生稻之间的可交配性.以栽培稻为对照,用光学显微镜观察不同野生稻花粉在同一栽培种柱头上的萌发生长情况.结果表明,在栽培稻柱头上普通野生稻(AA)花粉萌发最好,与对照萌发情况相近.药用野生稻(CC)萌发差,表现为柱头上花粉附着量少,开始萌发时间迟,萌发量少,花粉管扭曲、缠绕、伸长慢等.四倍体野生稻未观察到有萌发现象.说明普通野生稻与栽培稻亲缘关系近,可交配性好;药用野生稻与栽培稻可交配性差;四倍体野生稻与栽培稻可交配性极差.由此推断,转基因水稻与普通野生稻通过花粉途径发生基因漂移的可能性很大,而与药用野生稻和其他基因组野生稻发生基因漂移的可能性很小.     

Different feeding behaviors in a single predatory mite species. 1. Comparative life histories of three populations of Phytoseiulus longipes (Acari: Phytoseiidae) depending on prey species and plant substrate

The spider mites Tetranychus evansi and T. urticae are key pests of tomato crops, for which no sustainable practical control strategy is available yet. A Brazilian (B) and an Argentinean (A) population of a phytoseiid predatory mite species, Phytoseiulus longipes, are able to develop and reproduce on T. evansi on tomato, whereas a Chilean (C) population is not. In order to better characterize the two distinct feeding behaviours of these three populations, life table data were assessed when the predator was offered T. evansi or T. urticae as prey on bean or tomato leaves. No effect of the prey offered nor the plant substrate was demonstrated on development durations of the three populations. However, immature mortality was low for the Argentinean and the Brazilian populations whatever the prey or plant substrate, whereas 89 % of P. longipes from Chile died before reaching adulthood when fed T. evansi on tomato. No difference in effect on female longevity was detected among the three populations. Finally, the demographic parameters of all populations were lower in presence of tomato compared to beans. Possible explanations for these results are discussed.     

Pollen-pistil size correlation and pollen size-number trade-off in species of Argentinian Nyctaginaceae with different pollen reserves

Data on pollen and pistil traits from 14 Argentinean Nyctaginaceae species with starch or lipids as pollen reserves are presented. We expect differences in the traits between these two groups of species, but the same pattern within each group for (a) the relationship between pollen size and pistil length assuming that pollen tube length is predetermined by provisions in the pollen independently of the pollen reserve type, and for (b) a trade-off between size and number because available resources for male function are not unlimited. In particular we expect that (a) species with longer pistils will have larger pollen grains, (b) pollen grain size and the number of pollen grains per flower will be negatively correlated. Significant differences in the mean pollen number per flower and mean pollen size were observed between species with different pollen reserve type but not for pistil length. Then, correlation analyses were performed for species with starchy pollen or with pollen with lipids separately. Pollen size - pistil length correlation was positive and significant for species with starchy pollen but not for species with pollen with lipids. On the other hand, pollen size - number correlation was not significant for both starchy and oil-rich species. Results suggest that pollen reserve type would be a relevant factor that constraint pollen size in species of Nyctaginaceae, and that this pollen trait should be considered when studying pollen-pistil relationships, mainly between species of those families with mixed pollen reserves.     

An oligonucleotide microarray for the identification and differentiation of trichothecene producing and non-producing Fusarium species occurring on cereal grain

Cereal grain may be infected with a number of Fusarium species some of which are producers of highly toxic compounds such as the trichothecenes. Correct identification of these species is essential for risk assessment of cereal grain for human or animal consumption. Most of the available methods for identification are either time consuming or aimed at only one or a few target species. Microarray technology offers parallel analysis of a high number of DNA targets. In this study 57 capture oligonucleotides (CO) were designed based upon Fusarium ITS2 rDNA sequences, and used for microarray production. From this array COs could be selected that were able to hybridise specifically to labelled PCR products from the ITS region of Fusarium graminearum/Fusarium culmorum, Fusarium pseudograminearum, Fusarium poae, Fusarium sporotrichioides, Fusarium equiseti, Fusarium langsethiae and Fusarium tricinctum/Fusarium avenaceum. A few COs showed some cross hybridisation to non-target species. In a preliminary experiment it was shown that this cross hybridisation could be eliminated by increasing hybridisation stringency. The array could be used to detect individual Fusarium species in mixed samples and in environmental samples. This study demonstrates the feasibility of oligonucleotide microarrays for parallel detection of a number of Fusarium species.     

Alternaria alternata prevalence in cereal grains and soybean seeds from Entre Ríos, Argentina

A mycological survey was carried out at Entre Ríos province, Argentina, on sorghum grain, maize, rice, soybean seeds and on freshly harvested and stored wheat. The isolation frequencies and relative densities of species belonging to genera Alternaria, Aspergillus, Fusarium, Penicillium and other fungi were calculated. Alternaria alternata was the major fungal species isolated from sorghum, rice, soybean seeds and on freshly harvested wheat, and a low incidence of Fusarium species was observed on the same substrates. In maize the major fungal species isolated was Fusarium verticillioides. The high incidence levels of A. alternata observed,suggest that it may be necessary to determine, among other mycotoxins, if Alternaria toxins occur in these commodities.     

Characterization of Fusarium species section Liseola by restriction analysis of the IGS region

Fusarium species section Liseola namely F. fujikuroi, F. proliferatum, F. andiyazi, F. verticillioides, and F. sacchari are well-known plant pathogens on rice, sugarcane and maize. In the present study, restriction analysis of the intergenic spacer regions (IGS) was used to characterize the five Fusarium species isolated from rice, sugarcane and maize collected from various locations in Peninsular Malaysia. From the analysis, and based on restriction patterns generated by the six restriction enzymes, Bsu151, BsuRI, EcoRI, Hin6I, HinfI, and MspI, 53 haplotypes were recorded among 74 isolates. HinfI showed the most variable restriction patterns (with 11 patterns), while EcoRI showed only three patterns. Although a high level of variation was observed, it was possible to characterize closely related species and isolates from different species. UPGMA cluster analysis showed that the isolates of Fusarium from the same species were grouped together regardless of the hosts. We conclude that restriction analysis of the IGS regions can be used to characterize Fusarium species section Liseola and to discriminate closely related species as well as to clarify their taxonomic position.     

Microbe‐mediated control of Aspergillus flavus in stored rice grains with a focus on aflatoxin inhibition and biodegradation

Biological control of mycotoxigenic fungi using antagonistic microbes is a promising alternative to agricultural chemicals for postharvest storage. In this study, we evaluated rice‐derived bacterial strains to identify biocontrol agents to inhibit Aspergillus flavus in stored rice grains. Consequently, we obtained three potential biocontrol strains (Microbacterium testaceum KU313, Bacillus megaterium KU143 and Pseudomonas protegens AS15) from 26 tested strains that were prescreened from the 460 strains isolated from rice grains. The three selected strains proved to be effective biocontrol agents showing antifungal activity against A. flavus and good colonisation ability on rice grains, along with inhibition of the fungal growth and aflatoxin production. In particular, P. protegens AS15 greatly inhibited the aflatoxins produced by A. flavus on rice grains to 8.68 (percent aflatoxin reduction relative to control = 82.9%) and 18.05 (68.3 %) ng g^?1 dry weight of rice grains, compared with the 50.89 and 56.97 ng g^?1 dry weight of rice grains of the MgSO₄ control at 1 and 2 weeks after inoculation, respectively. In addition, strain AS15 had a significant ability to not only degrade aflatoxin B₁ (the most harmful aflatoxin), but also utilise the toxin for bacterial growth in a nutrient‐deficient medium. Therefore, the selected bacterial strains could be environmentally sound alternatives for the management of A. flavus and aflatoxin production by reducing the fungal damage to stored rice grains. This would also reduce the human and animal health hazards associated with the consumption of fungus‐contaminated rice grains. To our knowledge, this is the first report of the potential of the bacterial species M. testaceum and P. protegens as biocontrol agents for controlling aflatoxigenic A. flavus on stored rice grains.     

Mycological survey of selected health foods.

A survey was conducted to compare the total viable fungal content and the number of different mold species encountered in 10 types of health foods labeled organically grown and in the same foods without such a label. The foods were wheat flour, corn meal, brown rice, figs, split peas, pinto beans, soybeans, walnuts, pecans, and peanuts. Results showed no consistent difference in either the total viable fungal content or the number of different mold species encountered between the labeled and unlabeled foods. Two genera of yeasts (Rhodotorula and Saccharomyces) and 22 gener of molds, including more than 65 species, were encountered. The mold flora was dominated by Aspergillus glaucus, Aspergillus niger, Aspergillus flavus, Aspergillus candidus, Penicillium cyclopium, and Penicillium viridicatum. Isolates of the genera Alternaria, Cladosporium, Fusarium, and Helminthosporium also occurred in certain foods. At least 10 toxicogenic species of Aspergillus and Penicillium were encountered. A total of 87 cultures of these species, all isolated from health foods, were screened for laboratory production of their respective toxins. Toxin production potential of these 87 cultures did not differ from that of cultures of the same species isolated from conventional foods.     

Incidence of aflatoxins and aflatoxin producing fungi in animal feedstuffs

Fifty four samples including 5 of broken rice, 8 of corn grains, 8 of corn gluten feed, 13 of cottonseed cake and 4 each of rice polish, corn gluten, sesame oil cake, guar meal and wheat bran were screened for the presence of aflatoxins. Among all the samples, 14 were damaged and 40 apparently undamaged. The incidende of aflatoxins was found to be 60, 25, 25, and 23 per cent in broken rice, corn grains, corn gluten feed and cottonseed cake. Aflatoxins were not detected from rice polish, corn gluten, sesame oil cake, guar meal and wheat bran. Damaged sample revealed a much higher incidence i.e. 50 per cent as compared to undamaged ones i.e. 7.5 per cent. Mean concentration of aflatoxin B and G was found to be 15.5 and 12.2 ppb respectively.Cultural examination of aflatoxin positive feedstuffs yielded 39 isolates of different fungi including 21 of Aspergillus, 7 of Mucor, 6 of Rhizopus, 4 of Fusarium and one of Penicillium. These strains when tested for aflatoxin producing ability, revealed this property in only one isolate, identified as Aspergillus parasiticus.     

Mycological survey of selected health foods.

A survey was conducted to compare the total viable fungal content and the number of different mold species encountered in 10 types of health foods labeled organically grown and in the same foods without such a label. The foods were wheat flour, corn meal, brown rice, figs, split peas, pinto beans, soybeans, walnuts, pecans, and peanuts. Results showed no consistent difference in either the total viable fungal content or the number of different mold species encountered between the labeled and unlabeled foods. Two genera of yeasts (Rhodotorula and Saccharomyces) and 22 gener of molds, including more than 65 species, were encountered. The mold flora was dominated by Aspergillus glaucus, Aspergillus niger, Aspergillus flavus, Aspergillus candidus, Penicillium cyclopium, and Penicillium viridicatum. Isolates of the genera Alternaria, Cladosporium, Fusarium, and Helminthosporium also occurred in certain foods. At least 10 toxicogenic species of Aspergillus and Penicillium were encountered. A total of 87 cultures of these species, all isolated from health foods, were screened for laboratory production of their respective toxins. Toxin production potential of these 87 cultures did not differ from that of cultures of the same species isolated from conventional foods.     

Influence of the interactions among ecological variables in the characterization of zearalenone producing isolates of Fusarium spp

To carry out the physiological characterization of Fusarium graminearum and F. culmorum isolates with regard to its zearalenone producing ability, an in-depth experiment with a full factorial design was conducted. The effects and mutual interactions of temperature, moisture, substrate and isolate on the production of the toxin were studied. The study was done with twelve isolates of Fusarium (7 of F. graminearum and 5 of F. culmorum). The analysis of variance shows that there is a complex interaction of all of these factors, which can influence the relative concentrations of the mycotoxin produced, and hence, the correct physiological characterization of the strain. All the tested cultures were susceptible to invasion by Fusarium. The moisture content of grains (water activity values 0.960, 0.970 and 0.980) did not constitute a limiting factor for fungal growth or ZEA production, but incubation temperature (15 degrees C, 20 degrees C, 28 degrees C, and 32 degrees C) affected the rate of zearalenone synthesis. Very low or undetectable ZEA production was observed at 32 degrees C. All tested isolates showed a characteristic behavior concerning the optimum temperature for ZEA production, which was usually 20 degrees C maintained during the whole incubation period. This finding, which does not agree with other reports obtained with strains from different origins, suggests that there are genetic differences that would explain the particular physiological behavior of each isolate related to the optimal production conditions for ZEA. The existence of significant differences regarding the susceptibility of the assayed cereal grains (wheat, corn and rice) used for ZEA production by the different Fusarium species (F. graminearum and F. culmorum) is described for the first time in this paper.     

A molecular based strategy for rapid diagnosis of toxigenic Fusarium species associated to cereal grains from Argentina

Fusarium species are worldwide causal agents of ear rot in cereals. Their toxigenic potential is a health risk for both humans and animals. In Argentina, most identification of these fungi has been based on morphological and cross-fertility criteria which are time consuming and require considerable expertise in Fusarium taxonomy and physiology. DNA based approaches have been reported as rapid, sensitive and specific alternatives to identify the main fumonisin and trichothecene-producing Fusarium species. In this work, we used PCR assays and the partial sequence of TEF1-alpha gene (Translation Elongation Factor-1 alpha) to identify the fumonisin and trichothecene-producing species in Fusarium isolates from diverse regions of Argentina. The relative efficiency and reliability of those methods to improve mycotoxin risk prediction in this country were also assessed. Species-specific PCR assays were targeted toward multicopy IGS (Intergenic Spacer of rDNA units) and on the toxin biosynthetic genes FUM1 (fumonisins) and TRI13 and TRI7 genes (trichothecenes). PCR assays based on FUM1 gene and IGS sequences allowed detection and discrimination of the fumonisin producers Fusarium proliferatum and Fusarium verticillioides. Molecular identification of nonfumonisin producers from Gibberella fujikuroi species complex was possible after determination of TEF1-alplha gene sequences, which indicated the presence of Fusarium subglutinans, Fusarium andiyazi and Fusarium thapsinum. TEF-1 alpha gene sequences also allowed discrimination of the different species of the Fusarium graminearum complex (F. graminearum sensu lato) as F. graminearum sensu stricto, Fusarium meridionale and Fusarium boothii. The last two species belonged to NIV chemotype and were detected for the first time in the subtropical region of Argentina while F. graminearum sensu stricto was DON producer only, which was also confirmed by specific PCR assays based on TRI137/TRI7 genes. Our results indicated that the PCR assays evaluated in this work are reliable diagnostic tools to detect the main toxigenic Fusarium species associated to cereal grains in Argentina. An extensive epidemiological survey based on the approach presented in this work is currently in progress to know the mycotoxigenic hazard of Fusarium species in cereal grains from the subtropical region of Argentina.