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 .

Background: Cerium oxide nanoparticles (CeO 2 NPs) are potent scavengers of cellular reactive oxygen species (ROS). Their antioxidant properties make CeO 2 NPs promising therapeutic agents for bone diseases and bone tissue engineering. However, the effects of CeO 2 NPs on intracellular ROS production in osteoclasts (OCs) are still unclear. Numerous studies have reported that intracellular ROS are essential for osteoclastogenesis. The aim of this study was to explore the effects of CeO 2 NPs on osteoclast differentiation and the potential underlying mechanisms. Methods: The bidirectional modulation of osteoclast differentiation by CeO 2 NPs was explored by different methods, such as fluorescence microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), quantitative real-time polymerase chain reaction (qRT-PCR), and Western blotting. The cytotoxic and proapoptotic effects of CeO 2 NPs were detected by cell counting kit (CCK-8) assay, TdT-mediated dUTP nick-end labeling (TUNEL) assay, and flow cytometry. Results: The results of this study demonstrated that although CeO 2 NPs were capable of scavenging ROS in acellular environments, they facilitated the production of ROS in the acidic cellular environment during receptor activator of nuclear factor kappa-Β ligand (RANKL)-dependent osteoclast differentiation of bone marrow-derived macrophages (BMMs). CeO 2 NPs at lower concentrations (4.0 µg/mL to 8.0 µg/mL) promoted osteoclast formation, as shown by increased expression of Nfatc1 and C-Fos, F-actin ring formation and bone resorption. However, at higher concentrations (greater than 16.0 µg/mL), CeO 2 NPs inhibited osteoclast differentiation and promoted apoptosis of BMMs by reducing Bcl2 expression and increasing the expression of cleaved caspase-3, which may be due to the overproduction of ROS. Conclusion: This study demonstrates that CeO 2 NPs facilitate osteoclast formation at lower concentrations while inhibiting osteoclastogenesis in vitro by inducing the apoptosis of BMMs at higher concentrations by modulating cellular ROS levels.

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In the era of climate change, due to increased incidences of a wide range of various environmental stresses, especially biotic and abiotic stresses around the globe, the performance of plants can be affected by these stresses. After oxygen, silicon (Si) is the second most abundant element in the earth’s crust. It is not considered as an important element, but can be thought of as a multi-beneficial quasi-essential element for plants. This review on silicon presents an overview of the versatile role of this element in a variety of plants. Plants absorb silicon through roots from the rhizospheric soil in the form of silicic or monosilicic acid. Silicon plays a key metabolic function in living organisms due to its relative abundance in the atmosphere. Plants with higher content of silicon in shoot or root are very few prone to attack by pests, and exhibit increased stress resistance. However, the more remarkable impact of silicon is the decrease in the number of seed intensities/soil-borne and foliar diseases of major plant varieties that are infected by biotrophic, hemi-biotrophic and necrotrophic pathogens. The amelioration in disease symptoms are due to the effect of silicon on a some factors involved in providing host resistance namely, duration of incubation, size, shape and number of lesions. The formation of a mechanical barrier beneath the cuticle and in the cell walls by the polymerization of silicon was first proposed as to how this element decreases plant disease severity. The current understanding of how this element enhances resistance in plants subjected to biotic stress, the exact functions and mechanisms by which it modulates plant biology by potentiating the host defence mechanism needs to be studied using genomics, metabolomics and proteomics. The role of silicon in helping the plants in adaption to biotic stress has been discussed which will help to plan in a systematic way the development of more sustainable agriculture for food security and safety in the future.

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