Fusarium verticillioides can be transmitted via seeds and cause systemic infection in maize (Zea mays L.); its mycotoxin has harmful effects on animal and human health. We combined QTL mapping in recombinant inbred line (RIL) populations with a genome-wide association study (GWAS) of 217 diverse maize lines using 224,152 single nucleotide polymorphisms (SNPs) under controlled conditions to determine the genetic architecture of F. verticillioides seed rot (FSR) resistance. Our study identified 8 quantitative trait loci (QTLs) and 43 genes associated with 57 SNPs that were correlated with FSR resistance through linkage mapping and GWAS, respectively. Among these, there were three candidate genes, namely GRMZM2G0081223, AC213654.3_FG004, and GRMZM2G099255, which were detected in both linkage mapping and GWAS. Furthermore, the near-isogenic lines (NILs) containing GRMZM2G0081223, which also had a susceptible parent background, were found to have a significantly improved level of resistance. In addition, the expression profile of the three candidate genes revealed that they all respond to the infection following inoculation with F. verticillioides. These genetic analyses indicate that FSR resistance is controlled by loci with minor effect, and the polymerization breeding of lines with beneficial alleles and candidate genes could improve FSR resistance in maize.Maize is one of the most important cereals in the world due to its high yield potential and its high demand for use as food, feed, and for industrial purposes. Maize is subject to a variety of biotic and abiotic stresses during its lifetime, which can significantly affect final yield and quality. The planting area for maize in China is 37.07 million hectares, of which the Huang-Huai-Hai region accounts for 39%. In this region, the incidence of soil-borne diseases in maize has increased over the years, which coincides with increases in the use of cultivation systems such as double cropping, no-tillage, and straw returned. Fusarium verticillioides (formerly Fusarium moniliforme), which is a commonly-found soil-borne fungal species, can be transmitted to seeds and cause systemic infection in maize 1 . Previous studies have confirmed that seeds infected with F. verticillioides are a source of root and stalk infection 2 . In addition, the fungus can be transmitted from the planted seed through to the developing kernels via the mature plant 1,[3][4][5] . The diseases caused by F. verticillioides include seedling blight, stalk rot, root rot, kernel rot, ear rot, and seed rot 5,6 . F. verticillioides infection can result in decreased grain yields, poor grain quality, and contamination by the mycotoxin fumonisin 7 . The fumonisins produced by F. verticillioides are known to cause a variety of diseases when ingested by animals, and have been implicated in human carcinogenesis and neural tube defects, as well as in plant diseases 6 .

Berberine, an alkaloid originally extracted from the plant Coptis chinensis and other herb plants, has been used as a pharmacological substance for many years. The therapeutic effect of berberine has been attributed to its interaction with nucleic acids and blocking cell division. However, levels of berberine entering individual microbial cells minimal for growth inhibition and its effects on bacterial spores have not been determined. In this work the kinetics and levels of berberine accumulation by individual dormant and germinated spores were measured by laser tweezers Raman spectroscopy and differential interference and fluorescence microscopy, and effects of berberine on spore germination and outgrowth and spore and growing cell viability were determined. The major conclusions from this work are that: (1) colony formation from B. subtilis spores was blocked ~ 99% by 25 μg/mL berberine plus 20 μg/mL INF55 (a multidrug resistance pump inhibitor); (2) 200 μg/mL berberine had no effect on B. subtilis spore germination with L-valine, but spore outgrowth was completely blocked; (3) berberine levels accumulated in single spores germinating with ≥ 25 μg/mL berberine were > 10 mg/mL; (4) fluorescence microscopy showed that germinated spores accumulated high-levels of berberine primarily in the spore core, while dormant spores accumulated very low berberine levels primarily in spore coats; and (5) during germination, uptake of berberine began at the time of commitment (T1) and reached a maximum after the completion of CaDPA release (Trelease) and spore cortex lysis (Tlysis).

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Antibiotic resistance genes and bacteria (ARGs and ARB) in vegetable or fruit pose risks to ecological environment health. However, the assessment of ARGs and ARB from one popular vegetable, fresh tomato, has not been carried out before. In this study, high-throughput quantitative PCR and 16S rRNA gene Illumina sequencing technology were used to explore the antibiotic resistance characteristics of bacteria on five common cultivars of fresh tomatoes from supermarket. A total of 191 ARGs and 10 mobile genetic elements (MGEs) were detected on the tomato surfaces. The distribution profile of ARGs and MGEs was different among samples, with the organic tomatoes showing more ARGs and MGEs number and relative abundance. Aminoglycoside resistance genes strA and strB, sulfonamide resistance gene sul1, and multidrug resistance gene qacΔ1-01 were the predominant ARGs. Dominant MGEs were transposase genes, which might promote horizontal gene transfer (HGT) of ARGs. Network analysis indicated that fifteen bacterial families might be the potential hosts of ARGs, and the detected MGEs might have positive correlation with ARGs. These results revealed the bacterial ARGs and MGEs from fresh tomato, which might help guide human to pay more attention to ecological environment impacts of ARGs and ARB on the surfaces of vegetable or fruit.Keywords Fresh tomato • Antibiotic resistance genes • Mobile genetic elements • Bacterial community Highlights• Diverse ARGs and MGEs were found on tomato surfaces.• Organic tomatoes showed more abundant ARGs and MGEs.• Shared ARGs and MGEs were revealed on tomato surfaces.• Network analysis displayed significant correlation among ARGs, MGEs and bacteria.