Fumonisin Contamination Research Articles

Effect of seed biopriming with Trichoderma harzianum strain INAT11 on Fusarium ear rot and Gibberella ear rot diseases

Fusarium ear rot (FER) and Gibberella ear rot (GER) are common fungal diseases of maize responsible for yield losses and reduced kernel quality due to contamination by mycotoxins. Since no chemical treatments are available to control Fusarium disease in maize, biological control could represent a promising sustainable strategy. A commercial strain of Trichoderma harzianum (INAT11) was evaluated for its ability to antagonize Fusarium verticillioides and Fusarium graminearum and to reduce disease symptoms in plants through induction of a systemic resistance response in maize. Infection trials on maize plants under controlled greenhouse conditions showed that INAT11 applied to seeds is capable of reducing both F. verticillioides and F. graminearum disease incidence (37.1% and 30.7%, respectively) and severity (32.6% and 43.4%, respectively). Field trials performed under natural infection conditions showed a reduction in deoxynivalenol contamination in kernels, while no effect on fumonisin contamination was observed. The expression patterns of some defence-related genes belonging to both the ISR (LOX10, AOS, HPL and OPR8) and SAR pathways (PAL and PR1) indicated the upregulation of some ISR and SAR markers. These upregulations occurred at different levels likely related to the lifestyle of these two fungal pathogens.

A non-toxigenic Aspergillus flavus strain prevents the spreading of Fusarium verticillioides and fumonisins in maize

We evaluated Fusarium verticillioides and fumonisin contamination in maize samples after application of a non-aflatoxigenic Aspergillus flavus strain in the field. The sampling was performed 150 days after planting. The results showed a reduction in F. verticillioides frequency, as well as in fumonisin levels when samples were obtained from field areas treated with non-aflatoxigenic A. flavus strain. These results suggested a competition for substrate or space between fungi reducing the frequency of F. verticillioides and, consequently, fumonisin production.

A loop-mediated isothermal amplification (LAMP) assay for rapid detection of fumonisin producing Aspergillus species

Fumonisins contamination of food commodities is a worldwide problem, especially for maize. The ability to produce fumonisinsis a trait of several species of Fusarium, mainly F. verticillioides and F. proliferatum on maize, and some Aspergillus species. A. niger and its sister species A. welwitschiae, can contribute to fumonisin B2 (FB2) accumulation in maize kernels, although to a lesser extent than fumonisin-producing Fusarium species.Fumonisins risk monitoring represents an effective strategy in the integrated approach for mycotoxin risk management and reduction. The availability of a user-friendlymolecular assay for the detection oftoxigenic fungal species represents a valuable tool in understanding and managing upcoming mycotoxin contamination.In this study, we developed a LAMP assay, based on the detection of fum10, for a rapid and specific molecular detection of FB2-producing A. niger and A. welwistchiae, potentially useful to perform monitoring directly “on site” in maize chain. Results showed that very low amounts of conidia are suitable to detect the presence of the target gene, thus providing information about the presence of FB2-producing Aspergillus species and the possible upcoming fumonisins contamination in maize. The assay was combined with a suitable protocol for “in field” crude DNA extraction and a colorimetric method for easy naked-eye evaluationof results, offering a reliable and user-friendly tool to support effective reduction strategies of mycotoxin contamination in crop management programs.

Fate of moniliformin during different large-scale maize dry-milling processes

Moniliformin is a widespread emerging mycotoxin. Despite all the data so far present in the scientific literature there is a lack of information on the fate of MON during the maize milling. Thus, in order to collect new occurrence data on the fate of the MON in maize food products, also in relation to the FBs, 4 maize lots have been processed through a dry-degermination and a tempering-degermination dry-milling process. The whole grain before and after cleaning, and all the products and the by-products were sampled twice for each lot and were subjected to moniliformin and fumonisin LC-MS/MS analysis.The sum of the 3 food-grade products from tempering-degermination (flaking grits, medium and small hominy grits) only contributed to 4% of the total fumonisin contamination, but to as much as 19% of the total moniliformin contamination of the whole grain. Conversely, the pearl meal, break meal and maize flour from the dry-degermination system had a fumonisin and a moniliformin content that amounted to 12% and 16%, respectively, of the total contamination of the kernels.The results obtained in the present survey underline a weaker moniliformin decontamination than fumonisin abatement, which point out a higher risk of exposure for the end consumers.

In vitro inhibitory effect of the bacterium Serratia marcescens on Fusarium proliferatum growth and fumonisins production

Fumonisins are a family of hepatotoxic and nephrotoxic mycotoxins produced mainly by Fusarium verticillioides and F. proliferatum. F. proliferatum is an important pathogen colonizing an extraordinarily broad range of host plants worldwide and causing serious economic losses in agriculture, which has drawn our research attention. In order to manage F. proliferatum and its secondary metabolites in crop products and animal feed, the antifungal bacterium Serratia marcescens SerEW01 was isolated from the cuticle of earthworms. The strain strongly inhibited the germination of F. proliferatum conidia and mycelial growth, and suppressed fumonisins accumulation. S. marcescens SerEW01 has the capacity to synthesize chitinases, which degrade the cell walls of fungal mycelia. This research will enrich the resources of antifungal microorganisms and also provide a basis for the biological control of Fusarium proliferatum and fumonisins contamination management to enhance both the yield and quality of crop products and to ensure food and feed safety.

Occurrence of Fumonisins in Some Maize Meal Marketed to Consumers in Harare, Zimbabwe

Mycotoxins are toxic secondary metabolites secreted by filamentous fungi which affect animals, plants and humanscausing a lot of diseases. Fumonisins are the types that mostly affect cereal grains. The prevalence of fumonisins in Harare marketed maize meal was investigated in 72 randomly selected samples. Fumonisin B1 and Fumonisin B2 were extracted from maize meal with methanol-water (3:1, v/v) using ultrasonic extraction. They were injected into an LC-MS system following centrifugation. A survey was also conducted to determine the measures taken by 5 major Harare millers to mitigate fumonisin contamination in the maize meal. Fumonisin B1 (FB1) was detected in all analysed samples at mean concentrations ranging between 61.45 and 265.79 µg/kg. Fumonisin B2 (FB2) was detected in only 56.9 % of the samples analysed, with a range between 13.72 µg/kg and 76.93 µg/kg. The highest total fumonisin mean concentration (FB1+FB2) was detected in maize meal with maize bran added to it (342.72 µg/kg), while the least total fumonisin mean concentration was detected in maize meal with wheat bran added to it (61.45 µg/kg). All the samples analysed were within the maximum tolerable limit (MTL) of 1000 µg/kg. However, the average probable daily intake (APDI) of fumonisins ranged between 0.82 and 4.57 µg/kg body weight/day. Maize meal with maize bran added and Roller meal had PDMI above the regulatory limit of 2 µg/kg body weight/day recommended by the World Health Organisation. The high frequency of fumonisins consumed daily in these two types of maize meal could be posing some health risks to consumers.

359 Occurrence of mycotoxins in 2018 us corn-based feed ingredients

Abstract Mycotoxins are harmful secondary fungal metabolites that are detrimental to animal health and productivity. This study investigated occurrence and contamination levels of mycotoxins in the 2018 US corn harvest including corn grain, corn silage and corn by-product feed ingredients (distillers dried grains, gluten feed, etc.). Corn and corn silage samples marked as 2018 harvest from feed mills, livestock producers, and integrators and corn DDGS and other by-products from mid-August 2018 through January 2019 were screened via the LC-MS/MS technique for the presence of six major mycotoxin groups: aflatoxins, type A trichothecenes, type B trichothecenes (B-Trich), fumonisins (FUM), zearalenone (ZEN) and ochratoxin. Parameters of the main toxins found were compared to the two prior harvest years using the Kruskal-Wallis Test (Prism7, GraphPad, La Jolla, CA) and are presented in Table 1. Mean toxin count per sample in corn grain increased in 2018 versus 2017, returning to over two toxins per sample as in 2016. Mean B-Trich level (ppb) is elevated in 2018 from 2017. Although ZEN contamination does not differ from prior years, prevalence increased to 45% from 25% in 2017. Co-contamination in corn by-product feeds is steady, averaging nearly three toxins per sample. Mean B-Trich is higher than the 2017 crop, while FUM contamination is similar to 2017. ZEN levels in 2018 by-products are the highest seen in the past three years. Corn silage has increased in mean toxin count per sample and contamination levels of B-Trich and ZEN in 2018 versus 2017. Prevalence of B-trich has remained constant from year to year, while both ZEN and FUM prevalence have increased from 2017 to 2018. Preliminary results of the 2018 corn-based feed ingredients survey suggest mycotoxin occurrence and contamination levels are approaching those observed in the challenging 2016 crop with continued concerns for co-contamination.

Utilization of Synthetic Antibody for Fumonisin Determination in Feed and Food

Fumonisin contamination in food is limited around 2 – 4 ppm and in feed for different animals varies from 5 to 100 ppm. This regulation is to prevent animal and human from carcinogenic effect from fumonisins. Measurement of fumonisins frequently uses chromatography methods such as High-Performance Liquid Chromatography (HPLC) and Liquid chromatography tandem-mass spectrometry (LCMS/MS); however, the sample preparation and analysis process for these methods are costly and time consuming. Immunoassays have also been employed for detecting fumonisins in food or feed. Unfortunately, the instability of antibody to harsh condition such as high temperature and pH becomes the drawback for immunoassay method. Currently, the technology based on molecularly imprinting, which is called synthetic antibody, has been established for replacing antibody functions. Therefore, the aim of this review is to describe development of molecularly imprinted polymer (MIP) in fumonisin analysis in feed and food. Herein, the composition and production of MIP were described comprehensively. Bulk polymerization and solid phase synthesis were methods for production of MIP in micro and nano sizes. The application of MIP was reported for sample preparation as solid phase extraction measured continuously by HPLC showing the high recovery (> 60%). Then, MIP replaced antibody in direct competitive enzyme-linked immunosorbent assay (ELISA) for quantifying fumonisins in maize with high recovery (>90%) and limit detection (2 – 6 pM). Lastly, MIP was also employed in electrochemical sensor application as receptor for recognizing fumonisin in milk and maize. In conclusion, the performance of MIP has been applied successfully for fumonisin analysis comprehensively from sample preparation and quantification. The MIP would be developed for wider application for other toxins in feed or food such as veterinary drug, heavy metals, or pesticides.

Fumonisins in Serbian Corn: Long-time Assessment under Actual Climate Change Conditions

Maize samples collected in Serbia during a period of seven years were investigated on the presence of fumonisins. Concentration of fumonisins was determined by validated direct competitive Enzyme Linked Immunosorbent Assay method. This method was in accordance with European Union requirements, therefore accredited and performed in the Serbian accredited official laboratory. Summary analysis of all obtained results revealed fumonisins contamination in 82% of the total of 291 maize samples with average contamination being 1.515 mg/kg. An increase in the percentage of contaminated samples (from 51 to 100%), as well as an increase in mean fumonisin concentration in positive samples (from 0.227 to 3.281 mg/kg) and median values in positive samples (from 0.070 to 2.140 mg/kg) was noticed during the observation period. Although in Serbia there is no regular control of fumonisins in corn for animal feeding, long-term results indicate their wide distribution in this grain. Since the data on climate elements show change in temperature and precipitation in relation to multiannual average on the territory of Serbia, further research on the effects of climate change on the development of mold, the appearance of insects and the production of toxins are necessary in order to check the resistance of currently grown hybrids in the territory of Serbia on fungal growth and fumonisins production.

Influence of socio-economic and agronomic factors on aflatoxin and fumonisin contamination of maize in western Kenya.

Consumption of maize contaminated with mycotoxins has been associated with detrimental health effects. A farm survey covering 116 push‐pull and 139 non‐push‐pull cropping systems was conducted to determine the socio‐economic and agronomic factors that influence farmers’ knowledge on incidence and contamination of maize by ear rots and associated mycotoxins in western Kenya. All the respondents were smallholder farmers between the ages of 23 and 80 years, with 50% of them being female. Maize samples were collected from the standing crop in the field of each interviewed farmer and analyzed for aflatoxin and fumonisin. Only a small proportion of farmers had knowledge of aflatoxin and ear rots in maize. Overall, less than 20% of maize samples were contaminated with both aflatoxin and fumonisin, and more maize samples were contaminated with fumonisin as compared to aflatoxin. Proportions of maize samples containing higher than the acceptable Kenyan regulatory threshold (10 µg/kg) for aflatoxin and European Commission regulatory threshold (1,000) µg/kg for fumonisin were lower in maize samples from push‐pull cropping system. Age of farmer and county of residence were significantly and positively associated with knowledge of aflatoxin, while cropping system, county of residence, and level of education were positively associated with knowledge of maize ear rots. There was strong correlation between knowledge of maize ear rots and knowledge of aflatoxin. Levels of both aflatoxin and fumonisin were significantly and positively associated with the use of diammonium phosphate (DAP) fertilizer at planting. Aflatoxin levels were also positively associated with stemborer damage. Agronomic practices were not significantly different between push‐pull and non‐push‐pull farmers. However, use of DAP fertilizer was the most important agronomic factor since it was associated with both aflatoxin and fumonisin contamination of maize. These results imply that creating awareness is key to mitigation of ear rots and mycotoxin contamination of maize. The results also suggest that the levels of aflatoxin and fumonisin in maize in western Kenya were influenced both by pre‐harvest agronomic practices and by the cropping system adopted, push‐pull or not.

The Relationship Analysis on Corn Stalk Rot and Ear Rot According to Fusarium Species and Fumonisin Contamination in Kernels.

Fusarium diseases, including corn root rot, sheath rot, stalk rot, and ear rot are frequently occurring in maize producing areas of China. Fusarium stalk rot and ear rot are the most serious diseases and often occur at the same time, but it is unclear whether there is a correlation between Fusarium composition and disease occurrence. This study was conducted to clarify the relationship between the two diseases. A total of 49 corn stalk rot samples were collected from 15 regions of eight provinces in China from 2016 to 2018. The pathogens were isolated and identified separately from stalks, ear stems, and kernels. The contents of the fumonisins (FB1 and FB2) were detected in kernels. The results showed that the main Fusarium species were found in corn kernels, ear stems and stalks at the same time. The results showed that 1201 strains of Fusarium verticillioides, 668 strains of Fusarium oxysporum, 574 strains of Fusarium graminearum species complex (FGSC), 318 strains of Fusarium equiseti, 95 strains of Fusarium proliferatum, and 40 strains of Fusarium subglutinans were isolated from 1470 corn kernels, 245 ear stems, and 1225 stalks randomly selected from 49 samples. The contamination rate of fumonisins in the 49 samples was 57.1% with an average content of 1.9 μg/g, of which four samples exhibited higher levels as set by the European Commission (4.0 μg/g). These results provide a certain association between stalk rot and ear rot and lay a foundation to study the relationships among Fusarium maize diseases.

Assessment of Aflatoxin and Fumonisin Contamination and Associated Risk Factors in Feed and Feed Ingredients in Rwanda.

Mycotoxins are fungal metabolites that contaminate crops, food, and animal feeds. Aflatoxins and fumonisins are among the mycotoxins that have been increasingly reported to affect health and productivity of livestock globally. Given that the health and productivity of livestock can directly influence human food safety and security, a study was conducted to assess the levels and factors for aflatoxin and fumonisin contamination in feed and feed ingredients in Rwanda. Aflatoxins and fumonisins were analyzed in 3328 feed and feed ingredient samples collected at six time points between March and October 2017 in all 30 districts of Rwanda. Of the 612 participants providing samples, there were 10 feed processors, 68 feed vendors, 225 dairy farmers, and 309 poultry farmers. Enzyme-Linked Immunosorbent Assay (ELISA) was used for aflatoxin and fumonisin analyses. Mean aflatoxin levels of 108.83 µg/kg (Median (MD): 43.65 µg/kg), 103.81µg/kg (MD: 48.4 µg/kg), 88.64 µg/kg (MD: 30.90 µg/kg), and 94.95 µg/kg (MD: 70.45 µg/kg) were determined for dairy farmers, poultry farmers, feed vendors, and feed processors, respectively. Mean fumonisin levels were 1.52 mg/kg (MD: 0.71 mg/kg), 1.21 mg/kg (MD: 0.56 mg/kg), 1.48 mg/kg (MD: 0.76 mg/kg), and 1.03 mg/kg (MD: 0.47 mg/kg) for dairy farmers, poultry farmers, feed vendors, and feed processors, respectively. Aflatoxin contamination was significantly affected by time of sampling and district from which feed samples originated (p < 0.05). Fumonisins did not show any correlation trends. Ninety-two percent of survey participants were unaware of aflatoxins and fumonisins and their adverse effects. This study has provided the basic understanding of the extent of feed contamination across the country and has established a baseline for future interventions in Rwanda. Further studies are needed to explore strategies for mitigating mycotoxins in the feed value chain in Rwanda.

Relationship Between Invasive Brown Marmorated Stink Bug (Halyomorpha halys) and Fumonisin Contamination of Field Corn in the Mid-Atlantic U.S.

Brown marmorated stink bug (Halyomorpha halys Stål) is an invasive agricultural pest that causes severe damage to many crops. To determine potential associations between H. halys feeding damage, Fusarium infection, and mycotoxin contamination in field corn, a field survey was conducted in eight counties in Virginia. Results indicated an association between H. halys feeding damage and fumonisin contamination. Subsequent field experiments in Delaware, Maryland, and Virginia examined the ability of H. halys to increase Fusarium verticillioides (Sacc.) Nirenberg infection and fumonisin concentrations in corn. At the milk stage, H. halys (0 or 4 adults) and Fusarium (with or without F. verticillioides inoculum) treatments were applied to bagged ears in a two by two factorial randomized complete block design with 12 replicates. H. halys treatments increased levels of feeding damage (P < 0.0001) and Fusarium infection (P = 0.0380). Interaction between H. halys and Fusarium treatments influenced severity of infection (P = 0.0018) and fumonisin concentrations (P = 0.0360). Results suggest H. halys has the ability to increase both Fusarium infection and fumonisin concentrations in field corn. Further studies are needed to understand mechanisms by which H. halys increases fumonisin and to develop management strategies to mitigate impacts of H. halys on field corn in the region.

Contamination of sesame seed grown in Mississippi with aflatoxin, fumonisin, and mycotoxin-producing fungi

Four sesame varieties (S-34, S-35, S-38, and S-39) were planted in the Mississippi Delta in 2014 and 2015 at four nitrogen fertiliser application rates from 44.8 to 112 kg N/ha, and evaluated for grain yield and contamination by mycotoxins and toxigenic fungi. Variety S-35 had the highest yield in both years. Harvest seed moisture was not related to variety, because opposite results were obtained in the two years. N fertiliser application rate had no effect on yield or mycotoxin contamination of harvested seed in 2014, but significantly increased yield in 2015. Harvested sesame seed density was influenced by treatments (N rates and variety) with varietal differences occurring in the different years. While observed differences were small, even small differences could impact marketability. There was no significant effect of N fertiliser application rate, variety, crop year or interaction between them for contamination of harvested seed by aflatoxins, fumonisins,Aspergillus flavus orFusarium verticillioides in cleaned and uncleaned harvested sesame seed. Similar results were obtained from trials conducted in the Florida Panhandle during 2015. In general, sesame seed is not susceptible to aflatoxin and fumonisin contamination. None of the mycotoxin levels observed in this study were significant in regard to human or animal health, but further testing is needed. This is the first report of fumonisin found in sesame seed. The results of this study indicate that sesame seed is a safe crop for growers and consumers.

Impact of climatic conditions on fumonisins in maize grown in Serbia

The influence of climatic conditions on the levels of fumonisins in maize grown in Serbia was studied over eight years (2008 to 2015), investigating the possible relationship between the levels of fumonisins contamination in maize in relation to registered weather/climatic conditions. Presence of these mycotoxins in maize after harvest was evaluated based on climatic conditions within two periods: 10 days before and 10 days after 50% silking. Categories of fumonisins levels were transformed into classes. Chi-square test for association was used in analysing relationships between results of fumonisins levels and calendar years. Mann-Whitney U-test was used to compare differences between meteorological data of two subsets in years with high and low fumonisins level. There was a statistically significant association between the fumonisins levels and calendar years χ2=247.954; (P&lt;0.05). This study identified low precipitation and low humidity combined with high solar radiation as a critical parameter combination for elevated levels of fumonisins. The statistically significant difference in relation to some of the examined parameters suggests that maize in Serbian agro-climatic conditions is more susceptible to fungal colonisation, and subsequent fumonisin production in the period of 10 days before 50% silking.

Differences in Ear Rot Resistance and Fusarium verticillioides-Produced Fumonisin Contamination Between Polish Currently and Historically Used Maize Inbred Lines.

Poland is the fifth largest European country, in terms of maize production. Ear rots caused by Fusarium spp. are significant diseases affecting yield and causing grain mycotoxin contamination. Inbred lines, which are commonly used in Polish breeding programs, belong, mostly, to two distinct genetic categories: flint and dent. However, historically used lines belonging to the heterotic Lancaster, IDT and SSS groups were also present in previous Polish breeding programs. In the current study, 98 inbred lines were evaluated across a 2-year-long experiment, after inoculation with F. verticillioides and under natural infection conditions. Lancaster, IDT, SSS and SSS/IDT groups were characterized as the most susceptible ones and flint as the more resistant. Based on the results obtained, the moderately resistant and most susceptible genotypes were defined to determine the content of fumonisins (FBs) in kernel and cob fractions using the HPLC method. Fumonisin's content was higher in the grain samples collected from inoculated plants than in cobs. The association of visible Fusarium symptoms with fumonisin concentration in grain samples was significant. Conversely, the cobs contained more FB1 under natural infection, which may be related to a pathogen's type of growth, infection time or presence of competitive species. Using ddRADseq genome sampling method it was possible to distinguish a basal relationship between moderately resistant and susceptible genotypes. Genetic distance between maize genotypes was high. Moderately resistant inbreed lines, which belong to IDT and IDT/SSS belong to one haplotype. Genotypes which belong to the flint, dent or Lancaster group, and were characterized as moderately resistant were classified separately as the same susceptible one. This research has demonstrated that currently grown Polish inbred lines, as well the ones used in the past are a valid source of resistance to Fusarium ear rot. A strong association was observed between visible Fusarium symptoms with fumonisin concentration in grain samples, suggesting that selection in maize for reduced visible molds should reduce the risk of mycotoxin contamination. NGS techniques provide new tools for overcoming the long selection process and increase the breeding efficiency.

Aggressiveness and Fumonisins Production of Fusarium Subglutinans and Fusarium Temperatum on Korean Maize Cultivars

Fusarium root rot and stalk rot are becoming a threat to maize production worldwide. However, there is still limited information about the aggressiveness of Fusarium subglutinans Edwards and Fusarium temperatum and their relationship with fumonisin production. In this study, for the first time, the reaction of seven Korean maize cultivars to F. subglutinans and F. temperatum was investigated. The results showed that among the maize cultivars, Hik-chal and Miheung-chal had the highest Fusarium-induced root rot and stalk rot severity, while De Hack-chal had the lowest disease severity regardless of the Fusarium species. Furthermore, the disease resistant cv. De Hack-chal accumulated low levels of fumonisins (FUM) in the infected stalk, while cv. Hik-chal and Miheung-chal had the highest level of FUM. It is worth to note that, plants infected with F. temperatum had a higher FUM concentration compared to cultivars infected with F. subglutinans. The present study shows a significant correlation between stalk rot ratings and FUM levels and it also presents new information about the potential risk of FUM contamination of maize stalk with F. subglutinans and F. temperatum in South Korea. In addition, enzyme activities like polyphenol oxidase (PPO), peroxidase (POD), and the amount of total phenol content (TPC) were studied in selected susceptible cultivar Miheung-chal and resistant cultivar De Hack-chal. The activity of PPO, POD and concentration of TPC were generally higher in the roots of the resistant cultivar than the susceptible cultivar. Moreover, following inoculation of either F. subglutinans or F. temperatum, there was a significant increase in PPO and POD activity in the roots of both cultivars. Hence, the information provided in this study could be helpful to better understand the mechanisms of resistance response to infection of Fusarium root rot pathogens.

Diverse Components of Resistance to Fusarium verticillioides Infection and Fumonisin Contamination in Four Maize Recombinant Inbred Families.

The fungus Fusarium verticillioides can infect maize ears, causing Fusarium ear rot (FER) and contaminating the grain with fumonisins (FUM), which are harmful to humans and animals. Breeding for resistance to FER and FUM and post-harvest sorting of grain are two strategies for reducing FUM in the food system. Kernel and cob tissues have been previously associated with differential FER and FUM. Four recombinant inbred line families from the maize nested associated mapping population were grown and inoculated with F. verticillioides across four environments, and we evaluated the kernels for external and internal infection severity as well as FUM contamination. We also employed publicly available phenotypes on innate ear morphology to explore genetic relationships between ear architecture and resistance to FER and FUM. The four families revealed wide variation in external symptomatology at the phenotypic level. Kernel bulk density under inoculation was an accurate indicator of FUM levels. Genotypes with lower kernel density—under both inoculated and uninoculated conditions—and larger cobs were more susceptible to infection and FUM contamination. Quantitative trait locus (QTL) intervals could be classified as putatively resistance-specific and putatively shared for ear and resistance traits. Both types of QTL mapped in this study had substantial overlap with previously reported loci for resistance to FER and FUM. Ear morphology may be a component of resistance to F. verticillioides infection and FUM accumulation.

Development of Indirect Competitive Enzyme-Linked Immunosorbent Assay to Detect Fusarium verticillioides in Poultry Feed Samples.

Fumonisins are a group of toxic secondary metabolites that are produced by Fusarium verticillioides which are associated with poultry health hazard and great economic losses. The objective of the present study was to develop an immunological method to detect F. verticillioides in poultry feed samples. An indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) based on a polyclonal antibody against 67 kDa protein of the F. verticillioides 97K exoantigen was developed to detect this fungus. Antibody anti-67 kDa protein showed cross-reactivity against F. graminearum (2–7%) and F. sporotrichioides (10%), but no or low cross-reactivity against Aspergillus sp. and Penicillium sp. exoantigens. The detection limit for the 67 kDa protein of F. verticillioides was 29 ng/mL. Eighty-one poultry feed samples were analyzed for Fusarium sp. count, 67 kDa protein of F. verticillioides and fumonisin concentrations. Eighty of the 81 feed samples (98.6%) showed Fusarium sp. contamination (mean 6.2 x 104 CFU/g). Mean 67 kDa protein and fumonisin concentration in the poultry feed samples was 21.0 µg/g and 1.02 µg/g, respectively. The concentration of 67 kDa protein, as determined by ic-ELISA correlated positively (p < 0.05) with fumonisin levels (r = 0.76). These results suggest that this ic-ELISA has potential to detect F. verticillioides and predict fumonisin contamination in poultry feed samples.

Analysis of Fusarium ear rot and fumonisin contamination in testcrosses of a maize biparental population

Abstract Fusarium ear rot (FER) negatively affects maize production worldwide and poses a serious threat to human health for producing mycotoxins. The objectives of our study were to assess the factors affecting FER and fumonisin contamination in testcrosses of a maize population. In the trials, seeds of 191 testcrosses of IBMSyn4, 11 checks and 2 replications of parental lines (a total of 216 hybrids) were sown in three environments, in 2014 and 2015. FER disease intensity (DI), fumonisin contamination (FUMc) and number of ears with signs of European corn borer (ECB) attack were measured. Strong phenotypic and weak genetic correlations between DI, FUMc and ECB indicate randomness in the interaction of those traits. We detected three QTLs (chr.1, 2 and 6) for DI (LOD scores 3.77-5.06). The QTL on chr.2, confirmed across the environments, can serve as a guideline in breeding for FER resistance.