Background: Antimicrobial peptides play important roles in both plant and animal defense systems. Moreover, over-expression of CaAMP1 (Capsicum annuum antimicrobial protein 1), an antimicrobial protein gene isolated from C. annuum leaves infected with Xanthomonas campestris pv. vesicatoria, confers broad-spectrum resistance to hemibiotrophic bacterial and necrotrophic fungal pathogens in Arabidopsis. Phytophthora root and stem rot (PRR), caused by the fungus Phytophthora sojae, is one of the most devastating diseases affecting soybean (Glycine max) production worldwide. Results: In this study, CaAMP1 was transformed into soybean by Agrobacterium-mediated genetic transformation. Integration of the foreign gene in the genome of transgenic soybean plants and its expression at the translation level were verified by Southern and western blot analyses, respectively. CaAMP1 over-expression (CaAMP1-OX) lines inoculated with P. sojae race 1 exhibited enhanced and stable PRR tolerance through T₂–T₄ generations compared with the wild-type Williams 82 plants. Gene expression analyses in the transgenic plants revealed that the expression of salicylic acid-dependent, jasmonic acid-dependent, and plant disease resistance genes (R-genes) were significantly up-regulated after P. sojae inoculation. Conclusions: These results indicate that CaAMP1 over-expression can significantly enhance PRR tolerance in soybean by eliciting resistance responses mediated by multiple defense signaling pathways. This provides an alternative approach for developing soybean varieties with improved tolerance against soil-borne pathogenic PRR.

The yellow nutsedge (Cyperus esculentus L. 1753) is an unconventional oil plant with oil-rich tubers, and a potential alternative for traditional oil crops. Here, we reported the first high-quality and chromosome-level genome assembly of the yellow nutsedge generated by combining PacBio HiFi long reads, Novaseq short reads, and Hi-C data. The final genome size is 225.6 Mb with an N50 of 4.3 Mb. More than 222.9 Mb scaffolds were anchored to 54 pseudochromosomes with a BUSCO score of 96.0%. We identified 76.5 Mb (33.9%) repetitive sequences across the genome. A total of 23,613 protein-coding genes were predicted in this genome, of which 22,847 (96.8%) were functionally annotated. A whole-genome duplication event was found after the divergence of Carex littledalei and Rhynchospora breviuscula, indicating the rich genetic resources of this species for adaptive evolution. Several significantly enriched GO terms were related to invasiveness of the yellow nutsedge, which may explain its plastic adaptability. In addition, several enriched Kyoto Encyclopedia of Genes and Genomes pathways and expanded gene families were closely related with substances in tubers, partially explaining the genomic basis of characteristics of this oil-rich tuber.