Background: Anthracnose is a soil-borne tomato (Solanum lycopersicum L.) disease caused by Colletotrichum coccodes and associated with early dying syndrome and postharvest fruits decays leading to significant yield losses. A biocontrol trial was conducted using Penicillium sp. and Gliocladium spp. isolates recovered from soil and compost for the evaluation of their antifungal potential against the target pathogen. Results: Cell-free culture filtrates of the microbial agents tested at different concentrations displayed an important antifungal activity based on pathogen mycelial growth inhibition and spore germination suppression. The highest antifungal potential was induced by Penicillium sp. CH6, G. catenulatum Gc1 and G. virens Gv1 cell-free filtrates applied at 3 concentrations (10, 15 and 20% v/v). C. coccodes mycelial growth was significantly reduced by 16 to 84% with chloroform and ethyl acetate extracts of Penicillium sp. CH6 and G. catenulatum Gc1 isolates applied at the concentrations 1, 2.5 and 5% v/v. These treatments had induced an important morphological alteration to pathogen mycelium expressed mainly by a decrease in colony melanization. Testing on pathogen-inoculated fruits, treatment based on cell-free culture filtrates and organic extracts had significantly reduced anthracnose severity as compared to control. Rot lesion diameter was significantly decreased about 22% following treatments with Penicillium sp. CH6 and G. catenulatum Gc1 cell-free filtrates. All chloroform and ethyl acetate extracts of isolates tested had suppressed disease severity by 11 to 59% and 14 to 85%, respectively, as compared to the untreated control. Conclusions: The results demonstrated the involvement of bioactive compounds in the cultural filtrates and organic extracts tested. These microbial agents may be explored as an alternative tool for the protection of tomato fruits from fungi-associated decays.

Mycotoxin contamination in wheat, a staple food critical to human nutrition, poses significant public health concerns. This study investigated the natural occurrence of 17 mycotoxins in Tunisian durum wheat, assessed the influence of soil tillage practices on mycotoxin contamination, and performed an associated exposure risk assessment. A total of 167 wheat samples were randomly collected over two years (2021 and 2022) from fields managed under conventional tillage (CT) and no-tillage (NT) systems during both pre- and post-harvest periods. Mycotoxins were extracted using the QuEChERS method and quantified via UHPLC-MS/MS. The results demonstrated contamination by ZEN, DON, OTA, ENA1, ENB, and ENB1. Among regulated mycotoxins, OTA was the most prevalent, detected in 68 out of 167 samples with a mean concentration of 1.85 µg/kg. ZEN was the most abundant, detected in 65 samples with a mean concentration of 26.85 µg/kg, while DON was less frequently detected in 62 samples with a mean concentration of 0.68 µg/kg. Regarding emerging mycotoxins, ENB was the most prevalent and abundant, found in 51 samples with a mean concentration of 10.13 µg/kg; ENB1 and ENA1 were detected in 20 and 10 samples, with mean concentrations of 3.38 µg/kg and 1.69 µg/kg, respectively. Furthermore, mycotoxin concentrations varied according to agricultural practices. DON, ZEN, ENA1, ENB, and ENB1 showed higher frequencies and concentrations (ranging from 0.08 to 210.11 µg/kg) in samples collected during the 2021 pre-harvest period from NT fields. In contrast, OTA exhibited greater prevalence and higher concentrations (ranging from 2.33 to 9.78 µ/kg) in samples collected during the 2022 post-harvest period from CT fields. The Estimated Daily Intake (EDI) of mycotoxins by Tunisian adults was calculated based on contamination levels in raw durum wheat from fields under NT and CT practices, resulting in the following values (ng/kg bw/day), with the first value corresponding to NT samples and the second to CT samples: OTA (17.3; 20.8), ZEN (466.3; 194.0), DON (8.0; 7.56), ENA1 (4.30; 18.85), ENB (105.17; 121.08), and ENB1 (49.91; 40.91). Both the Margin of Exposure (MOE) values for OTA and the Hazard Quotients (HQ) for ZEN and DON exceeded established safety thresholds, indicating potential health risks for Tunisian adults. These findings highlight the urgent need to implement stricter mycotoxin regulations in Tunisia and enhance surveillance systems. Further research is warranted to elucidate the mechanisms by which soil tillage practices influence mycotoxin contamination and to develop targeted mitigation strategies to ensure food safety.

Septoria tritici blotch (STB) is a major disease problem of wheat worldwide. To optimize the introgression of resistance genes in elite genotypes throughout traditional or molecular breeding programs, a full understanding of the quantitative inheritance of resistance to Zymoseptoria tritici, plant height (PH), and thousand kernel weight (TKW) is needed. In this study, maternal and cytoplasmic effects of resistance to STB were investigated using P1 (susceptible, high‐yielding line) and P2 (resistant, low‐yielding line) durum wheat lines and their F₁, RF₁, F₂, RF₂, BC₁, RBC₁, BC₂, and RBC₂ progeny, assessed for resistance to STB during three growing seasons. Duncan mean’s analysis revealed significant differences between generation means for STB, PH, and TKW. The two parents had an extreme pattern. The F₁ and RF₁ segregated close to their respective parents, suggesting the presence of cytoplasmic and maternal genetic effects for Z. tritici resistance, PH, and TKW. Separate generation mean’s analysis confirmed the results of the Duncan test. A three‐parameter model was found to be not adequate for all traits in all three growing years; while a digenic epistatic model with cytoplasmic or/and maternal effect was adequate for all cases. Narrow‐sense heritability was in the range of 50–60%, 30–69%, and 28–31% for STB, PH, and TKW, respectively. For STB, high heritability and the presence of fixable epistatic effect is encouraging and could lead to creating varieties with the right female parent to exploit cytoplasmic and maternal effects in order to improve resistance to Z. tritici in durum wheat.

Tan spot disease caused by Pyrenophora tritici-repentis was becoming more bred in Tunisia during the last decade. The search for resistant varieties against the increased virulence diversity of P. tritici-repentis is presently considered as a priority. Seven of the most commercialized durum wheat varieties in Tunisia (cvs. Maâli, Salim, Razzak, Monastir, Khiar, Inrat100, and Sculptur) were inoculated with five characterized fungal strains under field conditions, during two seasons. The variance analysis revealed that strains Ech8F₆ and B4.8 used in inoculation are the most virulent ones. These strains hosting ToxB gene caused chlorosis symptom on the tested varieties. The other strains induced necrosis with yellow halo and host ToxA gene were less virulent. The area under disease progress curve values revealed that Maâli is the most vulnerable genotype compared to the new selected varieties Monastir and Inrat100. A variable tolerance rate of the varieties to tan spot disease was also highly visible on yield components. The losses were about 22.2% of the thousand kernel weight in Maâli variety, 35% of spikes/m² in Inrat100 variety, 32.5% of kernel number/spike, and 25.2% of yield grain in Monastir variety. This effect evaluation of the strains harbouring ToxA and ToxB genes could be responsible for the identification of potentially susceptible genes Tsn1 and Tsc2 representing resistance sources for breeding programs.