Fumonisin B1 Production Research Articles

Difference between resistant and susceptible maize to systematic colonization as revealed by DsRed-labeled Fusarium verticillioides

Fusarium verticillioides was labeled with DsRed via Agrobacterium tumefaciens-mediated transformation to examine differences in colonization and reactions of resistant and susceptible inbred lines of maize (Zea mays L.). The extent of systemic colonization of F. verticillioides in roots from maize lines either resistant or susceptible to the fungus was studied by visualizing the red fluorescence produced by the fungus expressing DsRed. The difference in quantities of colony forming units (CFU) in roots and basal stems, production of fumonisin B1, and pH of root were determined. Although F. verticillioides colonized both resistant and susceptible lines, differences were observed in the pattern and extent of fungal colonization in the two types of maize lines. The fungus colonized the susceptible lines producing mosaic patterns by filling the individual root cells with hyphae. Such a pattern of colonization was rarely observed in resistant lines, which were less colonized by the fungus than the susceptible lines in terms of CFUs. The production of mycotoxin fumonisin B1 in roots from different lines was closely correlated with the amount of F. verticillioides colonization, rather than the pH or amylopectin concentrations in the root. The findings from this study contribute to a better understanding of the defense mechanism in resistant maize lines to F. verticillioides.

Sda1, a Cys2-His2 zinc finger transcription factor, is involved in polyol metabolism and fumonisin B1 production in Fusarium verticillioides.

The ubiquitous ascomycete Fusarium verticillioides causes ear rot and stalk rot of maize, both of which reduce grain quality and yield. Additionally, F. verticillioides produces the mycotoxin fumonisin B1 (FB1) during infection of maize kernels, and thus potentially compromises human and animal health. The current knowledge is fragmentary regarding the regulation of FB1 biosynthesis, particularly when considering interplay with environmental factors such as nutrient availability. In this study, SDA1 of F. verticillioides, predicted to encode a Cys-2 His-2 zinc finger transcription factor, was shown to play a key role in catabolizing select carbon sources. Growth of the SDA1 knock-out mutant (Δsda1) was completely inhibited when sorbitol was the sole carbon source and was severely impaired when exclusively provided mannitol or glycerol. Deletion of SDA1 unexpectedly increased FB1 biosynthesis, but reduced arabitol and mannitol biosynthesis, as compared to the wild-type progenitor. Trichoderma reesei ACE1, a regulator of cellulase and xylanase expression, complemented the F. verticillioides Δsda1 mutant, which indicates that Ace1 and Sda1 are functional orthologs. Taken together, the data indicate that Sda1 is a transcriptional regulator of carbon metabolism and toxin production in F. verticillioides.

Fusariotoxins in asparagus – their biosynthesis and migration

Asparagus is often infected by fungi of the Fusarium genus, a causal agent of crown and root rot, which decreases the quantity and quality of spears. Fusarium oxysporum and Fusarium proliferatum are the most severe asparagus pathogens, well known as mycotoxin producers, mainly fumonisins and moniliformin. The present study was undertaken to estimate fumonisin B1, moniliformin and ergosterol concentrations in asparagus tissue. Moreover, the possibility of toxin transport to the edible asparagus part during the inoculation by F. oxysporum and F. proliferatum of different plant parts (root, crown and stem base) and the potential risk for consumers were assessed. Our studies showed that the highest capability of producing fumonisin B1 and moniliformin was demonstrated from isolates of F. proliferatum. The highest level of fumonisin B1 in edible spears was detected when the asparagus crown was inoculated with F. oxysporum and F. proliferatum. The lowest concentration was found in the case of storage root inoculation, which corresponds with mycelium absence and the long distance from the roots to the stem. Similar results were demonstrated for moniliformin. The mycotoxin content was confirmed even in healthy spears (without disease symptoms and mycelium presence), which might indicate that the transport of mycotoxins is possible from the soil through the root system to the top part of the plants.

Effect of Zingiber officinale essential oil on Fusarium verticillioides and fumonisin production

The antifungal activity of ginger essential oil (GEO; Zingiber officinale Roscoe) was evaluated against Fusarium verticillioides (Saccardo) Nirenberg. The minimum inhibitory concentration (MIC) of GEO was determined by micro-broth dilution. The effects of GEO on fumonisin and ergosterol production were evaluated at concentrations of 500–5000μg/mL in liquid medium with a 5mm diameter mycelial disc of F. verticillioides. Gas chromatography–mass spectrometry showed that the predominant components of GEO were α-zingiberene (23.9%) and citral (21.7%). GEO exhibited inhibitory activity, with a MIC of 2500μg/mL, and 4000 and 5000μg/mL reduced ergosterol biosynthesis by 57% and 100%, respectively. The inhibitory effect on fumonisin B1 (FB1) and fumonisin B2 (FB2) production was significant at GEO concentrations of 4000 and 2000μg/mL, respectively. Thus, the inhibition of fungal biomass and fumonisin production was dependent on the concentration of GEO. These results suggest that GEO was able to control the growth of F. verticillioides and subsequent fumonisin production.

Phylogenetic analysis, fumonisin production and pathogenicity ofFusarium fujikuroistrains isolated from rice in the Philippines

Fusarium fujikuroi Nirenberg is a maize and rice pathogen causing important agricultural losses and produces fumonisins - mycotoxins which pose health risk to humans and farm animals. However, little information is available about the phylogenetics of this species and its ability to produce fumonisins in rice. We studied 32 strains isolated from rice in the Philippines and performed a phylogenetic analysis using the partial sequence of Elongation Factor 1 alpha (EF-1α) including isolates belonging to closely related species. Fumonisin B1 (FB1 ) production was analyzed in 7-day-old cultures grown in fumonisin-inducing medium by an enzyme-linked immunosorbent assay-based method and by real-time reverse transcriptase-polymerase chain reaction using primers for FUM1 gene, a key gene in fumonisin biosynthesis. Nucleotide diversities per site (π) were 0.00024 ± 0.00022 (standard deviation) for the 32 F. fujikuroi strains from the Philippines and 0.00189 ± 0.00143 for all 34 F. fujikuroi strains, respectively. F. fujikuroi isolates grouped into one cluster separated from the rest of isolates belonging to the closely related F. proliferatum and showed very low variability, irrespective of their geographic origin. The cluster containing strains of F. proliferatum showed higher intraspecific variability than F. fujikuroi. Thirteen of the 32 strains analyzed were FB1 producers (40.62%), with production ranging from 0.386 to 223.83 ppm. All isolates analyzed showed FUM1 gene expression above 1 and higher than the CT value of the non-template control sample. Both seedling stunting and elongation were induced by the isolates in comparison with the control. F. fujikuroi are distinct from F. proliferatum isolates based on phytogenetic analysis and are potential fumonisin producers because all are positive for FUM1 gene expression. No relationship between fumonisin production and pathogenicity could be observed.

Activity of natural compounds from peanut skins on Fusarium verticillioides growth and fumonisin B1 production

The objectives of this investigation were to evaluate the antifungal and antimycotoxigenic properties of peanut skin extracts (PSE) against Fusarium verticillioides. The PSE were prepared by a multisolvent extraction procedure, and the activity on growth parameters and fumonisin B1 (FB1) production of the three PSE was explored at different concentrations on potato dextrose agar and in artificially infected maize kernels, respectively. The results demonstrated that all PSE had a significant influence on growth rate or lag phase of F. verticillioides. The yellow and purple (250–500μgml−1) extracts decreased growth rate, whereas brown extract extended the lag phase. Only the yellow extract at 62.5μgml−1 was able to affect both growth rate and lag phase. With respect to mycotoxin production a significant stimulation on FB1 production was observed with purple (62.5μgml−1) and brown (250μgml−1) extracts. In contrast, a significant decreased in FB1 was observed at 62.5μgml−1 of yellow extract. These findings showed that natural compounds from PSE possess inhibitory effects on F. verticillioides growth and mycotoxin production. Thus, PSE could be use as an alternative to minimize fungal contamination.

Multiplex PCR analysis of fumonisin biosynthetic genes in fumonisin-nonproducing Aspergillus niger and A. awamori strains

To determine the genetic basis for loss of fumonisin B2 (FB2) biosynthesis in FB2-nonproducing Aspergillus niger and A. awamori strains, we developed multiplex PCR primer sets to amplify fragments of eight fumonisin biosynthetic pathway (fum) genes. Fragments of all eight fum genes were amplified from FB2-producing A. niger and A. awamori strains; from FB2-nonproducing strains four amplification patterns arose in which one or more fum gene fragments were absent. Southern hybridization analysis of strains yielding patterns 2 and 3 confirmed that loss of FB2 production in A. awamori is associated with gene deletions within the fumonisin biosynthetic gene cluster. In addition, we observed a fifth multiplex amplification pattern in which all eight fum gene fragments appeared. Reverse transcription-PCR analysis of strains yielding pattern 5 showed that the expression of at least one fum gene was reduced relative to expression in FB2-producing A. niger. This suggests that in these strains loss of FB2 production is a result of structural or regulatory mutations that alter gene expression or function. These results demonstrate a diversity of genotypes within FB2-nonproducing A. niger and A. awamori populations and provide tools useful for identifying certain non-toxigenic strains for industrial or ecological applications.

カビ汚染乾燥果実から分離された黒色コウジカビの同定とフモニシンB2産生

カビ汚染乾燥果実から分離された黒色コウジカビの同定とフモニシンB₂産生

Biorepress of fumonisin B1 production and their phytotoxicity on growth and ultrastructures of Maize (Zea mays) Seedlings

The results clearly indicated that the seed germinibility in the presence of FB1 was decreased with increasing their concentration, whereas the germinibility was uncompletely ceased at high concentrations, a slight initial lag in germination observed at lowest concentration 28.57 µg /ml and highest concentration 64.11 µg /ml, respectively compared with the control. At concentration of FB1 (28.57 µg /ml), elongation of the hypocotyls and epicotyls in seedlings slightly inhibited compared with the control. Chlorophyll a and b content of seedlings of Zea mays decreased with increasing concentrations of Fumonisin B1. Chlorophyll a content was 6.23, 3.88 and 3.91 (mg/ g fresh weight) at concentrations 28.57, 40.54 and 64.11 (µg /ml) of Fumonisin B1 compared with the control 8.55 mg/ g fresh weight. The ultrastructural studies indicate that there were dramatic differences between the treated and untreated tissues of Zea mays seedlings with the toxin FB1. The treated cells with FB1 are highly vacuolated compared with the untreated cells. Thin layer of external epidermis was observed in untreated cells while thick layer of external epidermis in treated cells was appeared. Sacchaaromyces cerevisiae reduced FB1 to 40.54 (µg /ml) compared with control 64.11(µg /ml) .On the other hand Trichoderma harizianum was more efficient in FB1 productivity where productivity was reduced to 28.57 (µg /ml) with 44.56 %.

Influence of light on growth, conidiation and the mutual regulation of fumonisin B2 and ochratoxin A biosynthesis by Aspergillus niger

Aspergillus niger is a fungus able to produce the carcinogenic mycotoxins ochratoxin A (OTA) and fumonisins. We analysed the influence of light of various wavelengths on growth, conidiation, fumonisin B2 (FB2) and OTA biosynthesis by A. niger ITEM 7097. Light from both sides of the spectrum, from long (627 nm) to short wavelengths (470-455 nm), had a stimulating effect on growth, with the highest stimulation under blue (455 nm, 1,700 Lux) and short-wave blue light (390 nm). Conidiation was reduced by 40% under a short blue wavelength (455 nm, 200 Lux), but strongly promoted under light at an even shorter wavelength (390 nm), with an increase of about 200 fold in comparison to the dark. Production of FB2 and OTA was mutually regulated by light. FB2 production was promoted under light conditions: red and blue light in particular increased FB2 biosynthesis by 40%. Conversely, OTA production was greatly inhibited under red and blue light in comparison to dark incubation, with a mean reduction of about 40 fold, indicating a reverse regulation of both biosynthetic pathways. Incubation under a 390 nm wavelength repressed the production of both toxins to non-detectable levels.

Experimental infection of Fusarium proliferatum in Oryza sativa plants; fumonisin B1 production and survival rate in grains

Fusarium proliferatum is a plant pathogenic fungus associated with crops such as asparagus and corn, and it possesses the ability to produce a range of mycotoxins, including fumonisins. In Asia, rice (Oryza sativa) is a staple cereal and is occasionally colonized by this fungus without obvious physiological changes. F. proliferatum is closely related to Gibberella fujikuroi (anamorph F. fujikuroi) responsible for Bakanae disease in rice; however there are few reports of F. proliferatum as a rice pathogen. In this study, we examined the pathogenic potential of F. proliferatum in rice plants with respect to browning, fumonisin production, and survival rates in rice grains. Fungal inoculation was conducted by spraying a conidial suspension of F. proliferatum onto rice plants during the flowering period. Browning was found on the stalk, leaf, and ear of rice. Fumonisin B1 was detected at levels from trace to 21ng/g grains, using tandem mass spectrometry. Fungal recovery after 6months indicated that F. proliferatum had high affinity to rice plants being still viable in grains. From this study, it can be concluded that F. proliferatum is a possible pathogen of rice and possesses a potential to produce fumonisin B1 in rice grains in the field.

Diversity of the Fusarium verticillioides and F. proliferatum isolates according to their fumonisin B1 production potential and origin

Species of the genus Fusarium are characterised by the exceptional intraspecies and interspecies variability in respect to morphological, physiological and genetic properties. Intraspecies and interspecies diversity of Fusarium verticillioides and Fusarium proliferatum isolates in the production of fumonisin B1 according to their origin from maize and wheat grains was studied. Fumonisin B1 production potential of investigated 42 isolates was assessed by HPTLC and ELISA method. All 22 and 20 investigated F. verticillioides and F. proliferatum isolates, respectively, had the ability to produce fumonisin B1 toxin. Fumonisin B1 production potential of F. verticillioides and F. proliferatum varied from 88.60 ppm to 1,300.60 ppm and from 2.37 ppm to 1,246.00 ppm, respectively. According to Mann-Whitnev U test, there were no significant differences between the fumonisin B1 production mean values of isolates of F. verticillioides originated from maize and wheat (628.13 ppm and 696.38 ppm, respectively), as well as, fumonisin B1 production mean values of F. proliferatum isolates (212.32 ppm and 158.07 ppm, respectively). Variability coefficient values indicated that fumonisin B1 production potential variability was more expressed in maize than wheat originated isolates for both species.

Genotyping of Fusarium verticillioides strains producing fumonisin B1 in feed associated with animal health problems

Summary Fusarium verticillioides (F. verticillioides) is not only a primary pathogen of maize, but also can cause disease in other crops such as sorghum. Pathogenicity is related to mycotoxin production such as fumonisin. In the present study, 24 isolates of F. verticillioides, which were previously identified by phenotype based methods, were re-identified using restriction fragment length polymorphism (RFLP) analysis. Digestion of the polymerase chain reaction (PCR) products with the restriction enzyme TasI allowed identifying four non- verticillioides strains that were discarded from our study. The genetic variations among the remaining 20 strains of F. verticillioides were analysed by random amplified polymorphic DNA (RAPD)-PCR method with 4 primers. Of the four primers tested, two primers produced polymorphic amplification patterns. Dendrogram for each primer indicated the distance of the strains to each other. Using primers of A, B, C and D, the isolates were divided to 8, 9, 7 and 7 groups, respectively. The results of this study indicated genetic relationship among DNA polymorphic patterns with geographic regions and the severity of fumonisin B1 (FB1) production. It seems that RAPD analysis is a suitable technique for strain typing of F. verticillioides.

Mycotoxin production by isolates of Fusarium lactis from greenhouse sweet pepper (Capsicum annuum)

Internal fruit rot, caused by Fusarium lactis, is an important disease of sweet pepper (Capsicum annuum) in Canadian greenhouses. Production of the mycotoxins fumonisin B₁ (FB₁), moniliformin (MON) and beauvericin (BEA) by F. lactis (17 isolates) and the related species F. proliferatum (three isolates) and F. verticillioides (one isolate), which are also associated with internal fruit rot, was evaluated on rice medium. All 21 isolates examined were found to produce BEA, at concentrations ranging from 13.28 to 1674.60 ppm, while 13 of 17 F. lactis isolates and two of three F. proliferatum isolates produced MON (0.23 to 181.85 ppm). Only one isolate of F. lactis produced detectable levels of FB₁ in culture, whereas all three F. proliferatum isolates and the F. verticilloides isolate produced this mycotoxin (0.28 to 314 ppm). Production of FB₁, MON and BEA was also evaluated in inoculated pepper fruits showing mild or severe symptoms of infection. FB₁ could be detected in both lightly and heavily diseased fruit tissue after inoculation with F. lactis, F. proliferatum or F. verticilloides, at concentrations ranging from 0.61 to 8.04 ppm. BEA was also detected in lightly and heavily diseased fruit tissue inoculated with F. lactis, as well as in heavily diseased tissue inoculated with F. proliferatum (3.00 to 19.43 ppm), but not in tissue inoculated with F. verticilloides. MON was detected in all tissues inoculated with F. proliferatum or F. verticilloides, and in heavily diseased tissue inoculated with F. lactis (0.03 to 0.27 ppm). The three mycotoxins were also found in naturally infected sweet pepper fruits exhibiting symptoms of internal fruit rot and collected from a commercial greenhouse. The production of MON, BEA and FB₁ alone or in combination by isolates of F. lactis suggests that development of internal fruit rot of sweet pepper is an important food safety concern, and that every effort should be made to cull infected fruit before it makes it to market.

Fumonisin B1 and its co-occurrence with other fusariotoxins in naturally-contaminated wheat grain

The natural occurrence of fumonisin B1 (FB1) and its co-occurrence with zearalenone (ZEA), T-2 toxin and deoxynivalenol (DON) were surveyed in 103 winter wheat samples collected after four to six-month storage in family barns from different locations in Serbia. All 103 samples were mycotoxin positive. The mean concentrations of all mycotoxins except ZEA were greater in 2005 than in 2007. FB1 was detected in 82.1% and 92.0% of all samples with ranges of 750–5400 μg kg−1 (mean, 2079.45 μg kg−1) and 750–4900 μg kg−1 (mean 918.76 μg kg−1) in 2005 and 2007, respectively. Moderate positive correlations were found between FB1 and DON concentrations (r = 0.56 in 2005 and r = 0.54 in 2007) and between FB1 and ZEA concentrations (r = 0.48 in 2005 and r = 0.60 in 2007), while a moderate negative correlation was detected between the production of FB1 and T-2 toxin in 2007 (r = −0.33). This is the first report of FB1 occurrence in naturally-contaminated wheat grain and its simultaneous occurrence with ZEA, DON and T-2 toxin in Serbia. Moreover, this is one of the rare reports presenting the occurrence of FB1 on wheat in the world.

HXK1 regulates carbon catabolism, sporulation, fumonisin B1 production and pathogenesis in Fusarium verticillioides

In Fusarium verticillioides, a ubiquitous pathogen of maize, virulence and mycotoxigenesis are regulated in response to the types and amounts of carbohydrates present in maize kernels. In this study, we investigated the role of a putative hexokinase-encoding gene (HXK1) in growth, development and pathogenesis. A deletion mutant (Δhxk1) of HXK1 was not able to grow when supplied with fructose as the sole carbon source, and growth was impaired when glucose, sucrose or maltotriose was provided. Additionally, the Δhxk1 mutant produced unusual swollen hyphae when provided with fructose, but not glucose, as the sole carbon source. Moreover, the Δhxk1 mutant was impaired in fructose uptake, although glucose uptake was unaffected. On maize kernels, the Δhxk1 mutant was substantially less virulent than the wild-type, but virulence on maize stalks was not impaired, possibly indicating a metabolic response to tissue-specific differences in plant carbohydrate content. Finally, disruption of HXK1 had a pronounced effect on fungal metabolites produced during colonization of maize kernels; the Δhxk1 mutant produced approximately 50 % less trehalose and 80 % less fumonisin B₁ (FB₁) than the wild-type. The reduction in trehalose biosynthesis likely explains observations of increased sensitivity to osmotic stress in the Δhxk1 mutant. In summary, this study links early events in carbohydrate sensing and glycolysis to virulence and secondary metabolism in F. verticillioides, and thus provides a new foothold from which the genetic regulatory networks that underlie pathogenesis and mycotoxigenesis can be unravelled and defined.

Incidence of fumonisin B2 production within Aspergillus section Nigri populations isolated from California raisins.

Fungi belonging to Aspergillus section Nigri occur frequently and in high populations on grapes. Species within this section include Aspergillus niger, A. tubingensis, and A. carbonarius, and they are potential sources for mycotoxins including ochratoxin A and fumonisin B(2) (FB(2)) in grapes and grape products. Aspergillus section Nigri strains were isolated from California raisins to examine the frequency and extent of FB(2) production. Of 392 strains isolated, 197 strains were identified as A. niger, 131 of which produced FB(2). These strains produced from 1.2 to 27 μg/ml FB(2) in culture. PCR amplification of fum1 and fum19 gene fragments showed that all FB(2)-producing strains and nearly all nonproducing strains of A. niger contain these genes. An additional 175 strains were identified as A. tubingensis, none of which produced FB(2). PCR with fum1 and fum19 primers amplified gene fragments of 14 and 25% of A. tubingensis strains, respectively, suggesting that putative orthologs of A. niger fumonisin biosynthetic genes might occur in A. tubingensis. These results indicate that FB(2) production is common among field isolates of A. niger and suggest that the potential for FB(2) contamination of California raisins should be addressed further.

In vitro inhibitory effect of tetrahydrocurcuminoids on Fusarium proliferatum growth and fumonisin B1 biosynthesis

Many plant pathogens produce toxic metabolites when growing on food and feed. Some antioxidative components seem to prevent fungal growth and mycotoxin formation. Recently, we synthesized a new class of powerful antioxidative compounds, i.e. tetrahydrocurcuminoids, and its structure/antioxidant activity relationships have been established. The South West of France produces large amounts of corn, which can be infected by Fusarium species, particularly F. proliferatum. In this context, the efficiency of tetrahydrocurcuminoids, which can be obtained from natural curcuminoids, was investigated to control in vitro the growth of F. proliferatum and the production of its associated mycotoxin, fumonisin B1. The relation between structure and antifungal activity was studied. Tetrahydrocurcumin (THC1), with two guaiacyl phenolic subunits, showed the highest inhibitory activity (measured as radial growth on agar medium) against the F. proliferatum development (67% inhibition at a concentration of 13.6 µmol ml−1). The efficiencies of THC2 (36% at a concentration of 11.5 µmol ml−1), which contains syringyl phenolic units, and THC3 (30% at a concentration of 13.6 µmol ml−1), which does not have any substituent on the aromatic rings, were relatively close. These results indicate that the simultaneous presence of guaiacyl phenols and the enolic function of the β-diketone moiety play an important role in the inhibition mechanisms. The importance of this combination was confirmed using n-propylguaiacol and acetylacetone as molecular models. Under the same conditions, ferulic acid and eugenol, other natural phenolic antioxidants, were less efficient in inhibiting fungal growth. THC1 also reduced fumonisin B1 production in liquid medium by approximately 35, 50 and 75% at concentrations of 0.8, 1.3, and 1.9 µmol ml−1, respectively. These very low inhibitory concentrations show that tetrahydrocurcuminoids could be one of the most promising biobased molecules for the control of mycotoxinogen fungal strains.

Fumonisin B2 production on agar media by Aspergillus niger of Japanese origin

Aspergillus niger is one of the most important fungi for industrial production of organic compounds. Recently, it has been reported that A. niger produces a typical Fusarium mycotoxin, fumonisin B2. However, currently there has been no report on the production of fumonisin B2 by A. niger of Japanese origin. In this study, we analyzed the production of fumonisin B2 with seven domestic A. niger strains. These strains were cultivated on agar media, harvested, and analyzed for fumonisins using the AOAC995.15 method with some modifications. One strain was found to produce fumonisin B2 in a media-dependent manner.

Field Studies on the Relationship betweenFusarium verticillioidesand Maize (Zea maysL.): Effect of Biocontrol Agents on Fungal Infection and Toxin Content of Grains at Harvest

Maize (Zea maysL.) is a staple food for the majority of the world's population.Fusarium verticillioides(Sacc.) Nirenberg (Teleomorph:Gibberella moniliformisWineland; synonym:F. moniliformis) is both a saprophyte and a parasite of maize and can also be found as an endophyte. The presence of this fungus in maize constitutes an imminent risk due to its ability to produce fumonisins, mycotoxins with proven carcinogenic effects. The present work investigated biocontrol activity ofBacillus amyloliquefaciensandMicrobacterium oleovoransagainstF. verticillioidesinfection and fumonisin B1production in field-grown maize during four consecutive growing seasons. Treatment withB. amyloliquefaciensconsistently reducedF. verticillioidesinoculum and fumonisin content of harvested grains.F. verticillioidescount and fumonisin levels correlated negatively with rainfall regimes; however, none of these parameters showed significant correlation with yields. Treatment with these biocontrol agents may improve phytosanitary quality of the grains and reduce toxicological risk in the maize agroecosystem.