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In this study, wild barley (Hordeum brevisubulatum) infected (E+) and uninfected (E-) by Epichloë bromicola were used for hydroponic experiments during the seedling stage. Various attributes, such as the effect of fungal endophyte on the growth and development of wild barley, the absorption of cadmium (Cd) and mineral elements (Ca, Mg, Fe, Mn, Cu, Zn), subcellular distribution, and chemical forms were investigated under CdCl2 stress. The results showed that the fungal endophy significantly reduced the Ca content and percentage of plant roots under Cd stress. The Fe and Mn content of roots, the mineral element content of soluble fractions, and the stems in the pectin acid or protein-chelated state increased significantly in response to fungal endophy. Epichloë endophyte helped Cd2+ to enter into plants; and reduced the positive correlation of Ca-Fe and Ca-Mn in roots. In addition, it also decreased the correlation of soluble components Cd-Cu, Cd-Ca, Cd-Mg in roots, and the negative correlation between pectin acid or protein-chelated Cd in stems and mineral elements, to increase the absorbance of host for mineral elements. In conclusion, fungal endophy regulated the concentration and distribution of mineral elements, while storing more Cd2+ to resist the damage caused by Cd stress. The study could provide a ground for revealing the Cd tolerance mechanism of endophytic fungal symbionts. The present study is the first to study the effect of fungal endophy on essential mineral elements of plants under heavy metal stress, filling a gap in the existing research. The study could be helpful to reveal the mechanism of endophytic fungi to improve the host's tolerance to heavy metals and provide a foundation for the grass-endophyte symbionts to improve heavy metal-contaminated soils as ecological grasses. [ABSTRACT FROM AUTHOR]

Knorringia sibirica is a typical species of Polygonaceae with high medicinal and ecological value. However, there are few available phylogenetic and genetic studies about the chloroplast genome of K. sibirica. In the current study, a comprehensive examination of the chloroplast genome of K. sibirica was performed. The K. sibirica chloroplast genome is 161,384 bp, circular with a typical quadripartite structure, and comprised of guanine + cytosine content of 37.63%. The genome consists of 131 genes, including 86 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Seventy simple sequence repeats were identified in the genome. When compared with three closely related species, the result revealed that the chloroplast genome of K. sibirica was conserved in genome composition and structure. The specific sites in the genome suitable for DNA barcodes were identified by calculation of the nucleotide diversity. Finally, a phylogenetic tree of 49 species in Polygonaceae was constructed using the whole chloroplast genome. The phylogenetic analysis suggested that Knorringia is an independent genus in the Polygonea tribe. This research could provide support for the utilization of genetic sources and the evolutionary study of K. sibirica. [ABSTRACT FROM AUTHOR]

This paper considers a fresh produce supply chain in which a retailer sources alternative produce from two competing suppliers. The suppliers make efforts to preserve product freshness, while the retailer, with demand forecast information, can share it with none, one or both of the suppliers strategically. By constructing a multistage game model, the optimal demand information sharing strategy in the supply chain is explored. The results show that the retailer has the willingness to disclose demand information only when the freshness elasticity is high. Significantly, with the improvement of the freshness elasticity, the retailer will transform from sharing information with both suppliers to one supplier. The suppliers are always willing to accept the information disclosed by the retailer. However, complete transparency of demand information may hurt the supply chain under certain conditions. To improve the supply chain performance, the retailer can charge both suppliers for information fees and adjust from sharing information with no suppliers to both suppliers with a relatively low freshness elasticity. Conversely, the retailer can change from sharing information with both suppliers to sharing information with one supplier through a charging contract with a relatively high freshness elasticity. [ABSTRACT FROM AUTHOR]

The present study provides a detailed analysis of the chloroplast genome of Microula sikkimensis. The genome consisted of a total of 149,428 bp and four distinct regions, including a large single-copy region (81,329 bp), a small single-copy region (17,261 bp), and an inverted repeat region (25,419 bp). The genome contained 112 genes, including 78 protein-coding genes, 30 tRNA genes, and 4 rRNA genes, and some exhibited duplication in the inverted repeat region. The chloroplast genome displayed different GC content across regions, with the inverted repeat region exhibiting the highest. Codon usage analysis and the identification of simple sequence repeats (SSRs) offer valuable genetic markers. Comparative analysis with other Boraginaceae species highlighted conservation and diversity in coding and noncoding regions. Phylogenetic analysis placed M. sikkimensis within the Boraginaceae family, revealing its distinct relationship with specific species. [ABSTRACT FROM AUTHOR]

The clavicipitaceous fungus Epichloë gansuensis forms symbiotic associations with drunken horse grass ( Achnatherum inebrians ), providing biotic and abiotic stress protection to its host. However, it is unclear how E. gansuensis affects the assembly of host plant-associated bacterial communities after ammonium nitrogen (NH 4 + -N) treatment. We examined the shoot- and root-associated bacterial microbiota and root metabolites of A. inebrians when infected (I) or uninfected (F) with E. gansuensis endophyte. The results showed more pronounced NH 4 + -N-induced microbial and metabolic changes in the endophyte-infected plants compared to the endophyte-free plants. E. gansuensis significantly altered bacterial community composition and β-diversity in shoots and roots and increased bacterial α-diversity under NH 4 + -N treatment. The relative abundance of 117 and 157 root metabolites significantly changed with E. gansuensis infection under water and NH 4 + -N treatment compared to endophyte-free plants. Root bacterial community composition was significantly related to the abundance of the top 30 metabolites [variable importance in the projection (VIP) > 2 and VIP > 3] contributing to differences between I and F plants, especially alkaloids. The correlation network between root microbiome and metabolites was complex. Microorganisms in the Proteobacteria and Firmicutes phyla were significantly associated with the R00693 metabolic reaction of cysteine and methionine metabolism. Co-metabolism network analysis revealed common metabolites between host plants and microorganisms.IMPORTANCEOur results suggest that the effect of endophyte infection is sensitive to nitrogen availability. Endophyte symbiosis altered the composition of shoot and root bacterial communities, increasing bacterial diversity. There was also a change in the class and relative abundance of metabolites. We found a complex co-occurrence network between root microorganisms and metabolites, with some metabolites shared between the host plant and its microbiome. The precise ecological function of the metabolites produced in response to endophyte infection remains unknown. However, some of these compounds may facilitate plant-microbe symbiosis by increasing the uptake of beneficial soil bacteria into plant tissues. Overall, these findings advance our understanding of the interactions between the microbiome, metabolome, and endophyte symbiosis in grasses. The results provide critical insight into the mechanisms by which the plant microbiome responds to nutrient stress in the presence of fungal endophytes., Competing Interests: The authors declare no conflict of interest.