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By incorporating an additional recovery compartment in the SLBS model, a new model, known as the SLBRS model, is proposed in this paper. The qualitative properties of this model are investigated. The result shows that the dynamic behavior of the model is determined by a thresholdℛ0. Specially, virus-free equilibrium is globally asymptotically stable ifℛ0≤1, whereas the viral equilibrium is globally asymptotically stable ifℛ0>1. Next, the sensitivity analysis ofℛ0to four system parameters is also analyzed. On this basis, a collection of strategies are advised for eradicating viruses spreading across the Internet effectively.

Genetic populations provide the basis for genetic and genomic research, and chromosome segment substitution lines (CSSLs) are a powerful tool for the fine mapping of quantitative traits, new gene mining, and marker-assisted breeding. In this study, 213 CSSLs were obtained by self-crossing, backcrossing, and marker-assisted selection between cultivated soybean (Glycine max [L.] Merr.) variety Suinong14 (SN14) and wild soybean (Glycine soja Sieb. et Zucc.) ZYD00006. The genomes of these 213 CSSLs were resequenced and 580,524 single-nucleotide polymorphism markers were obtained, which were divided into 3,780 bin markers. The seed-pod-related traits were analyzed by quantitative trait locus (QTL) mapping using CSSLs. A total of 170 QTLs were detected, and 32 QTLs were detected stably for more than 2 years. Through epistasis analysis, 955 pairs of epistasis QTLs related to seed-pod traits were obtained. Furthermore, the hundred-seed weight QTL was finely mapped to the region of 64.4 Kb on chromosome 12, and Glyma.12G088900 was identified as a candidate gene. Taken together, a set of wild soybean CSSLs was constructed and upgraded by a resequencing technique. The seed-pod-related traits were studied by bin markers, and a candidate gene for the hundred-seed weight was finely mapped. Our results have revealed the CSSLs can be an effective tool for QTL mapping, epistatic effect analysis, and gene cloning.

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There is growing interest in expanding the production of soybean oils (mainly triacylglycerol, or TAG) to meet rising feed demand and address global energy concerns. We report that a plastid‐localized glycerol‐3‐phosphate dehydrogenase (GPDH), encoded by GmGPDHp1 gene, catalyzes the formation of glycerol‐3‐phosphate (G3P), an obligate substrate required for TAG biosynthesis. Overexpression of GmGPDHp1 increases soybean seed oil content with high levels of unsaturated fatty acids (FAs), especially oleic acid (C18:1), without detectably affecting growth or seed protein content or seed weight. Based on the lipidomic analyses, we found that the increase in G3P content led to an elevated diacylglycerol (DAG) pool, in which the Kennedy pathway‐derived DAG was mostly increased, followed by PC‐derived DAG, thereby promoting the synthesis of TAG containing relatively high proportion of C18:1. The increased G3P levels induced several transcriptional alterations of genes involved in the glycerolipid pathways. In particular, genes encoding the enzymes responsible for de novo glycerolipid synthesis were largely upregulated in the transgenic lines, in‐line with the identified biochemical phenotype. These results reveal a key role for GmGPDHp1‐mediated G3P metabolism in enhancing TAG synthesis and demonstrate a strategy to modify the FA compositions of soybean oils for improved nutrition and biofuel.