Wheat stripe rust, caused by the fungal pathogen Puccinia striiformis f. sp. tritici (Pst), is a destructive wheat disease in China. The Gansu–Ningxia region (GN) is a key area for pathogen over-summering in China, and northwestern Hubei (HB) is an important region for pathogen over-wintering, serving as a source of inoculum in spring epidemic regions. The spatiotemporal population genetic structure of Pst in HB and the pathogen population exchanges between GN and HB are important for estimating the risk of interregional epidemics. Here, 567 isolates from GN and HB were sampled from fall 2016 to spring 2018 and were genotyped using simple sequence repeat markers. The genotypic and genetic diversity of Pst subpopulations in HB varied among seasons and locations. Greater genetic diversification levels were found in the spring compared with fall populations using principal coordinate analysis and Bayesian assignments. In total, there were 17 common genotypes among the 208 determined, as shown by a small overlap of genotypes in the principal coordinate analysis and dissimilar Bayesian assignments in both regions, which revealed the limited genotype exchange between the populations of GN and HB.

The increasing global antibiotic resistance has created a pressing need for new antimicrobial drugs. Antimicrobial peptides (AMPs) come into the spotlight for their antibacterial properties, particularly against multidrug-resistant pathogens. Since AMPs act locally, they achieve optimal antimicrobial effectiveness and face maximum evolutionary pressure within spatially confined, highly competitive microbiomes. This ecological principle justifies marine particles as promising reservoirs of untapped marine AMPs. Marine particles are ubiquitous throughout the ocean, ranging from the sunlit surface waters to the deepest hadal environments. They are densely colonized microhabitats where nutrient gradients, spatial proximity, chemical signaling, and interspecies competition among microorganisms converge—unique characteristics that position marine particles as natural laboratories for the evolution of novel AMPs. However, most marine microorganisms are challenging to cultivate. Fortunately, metagenomics is revolutionizing marine AMP discovery by enabling researchers to screen for elusive peptide-encoding genes and complex biosynthetic gene clusters in uncultivated microbial communities. Additionally, advancements in artificial intelligence are further transforming marine AMP bioprospecting by moving from passive exploration to active molecular understanding and navigation. This review synthesizes our current understanding of the microbial ecology and emerging technologies that drive marine AMP discovery, and explores the application potentials of marine AMPs in human medicine, agriculture, and mariculture.