Pear is one of the world's most important fruit crops, but the genetic story behind its origin, spread, and most desirable traits has remained difficult to untangle.

Researchers combined forest inventory data, satellite observations, and machine learning to estimate tree density across North America and evaluate the uncertainty of those estimates. The study suggests the continent contains between 339 billion and 514 billion trees with DBH＞10 cm and shows that estimates can vary substantially depending on forest definitions and tree size thresholds. The framework provides a consistent approach for large-scale forest monitoring, biodiversity assessment, and carbon accounting.

Researchers from the University of Georgia and the USDA Forest Service evaluated four strategies for predicting future tree diameters for "unobserved" species. They found that all four strategies can produce reliable predictions. However, approaches that incorporate species-specific information, such as post-hoc calibration using at least one repeated measurement or grouping rare species into an "others" category, tend to provide more precise results. The study offers practical guidance for forest managers working in species-rich tropical forests, where rare and unobserved species are common.

Antibiotic resistance in plant pathogens threatens sustainable crop protection, yet its molecular basis remains incompletely understood. This study reports that streptomycin resistance in Clavibacter michiganensis strain TX-0702 is mediated by a plasmid-borne aminoglycoside phosphotransferase, APH(3), encoded on an uncharacterized plasmid, pCM3. Functional and biochemical analyses demonstrate that APH(3) inactivates streptomycin through phosphorylation, establishing a phosphorylation-driven resistance mechanism in Gram-positive plant pathogens. Sequence analyses reveal that pCM3 carries mobile genetic elements, suggesting environmental dissemination of resistance genes in plant-associated microbes. These findings expand understanding of phytopathogen antibiotic resistance and highlight plant microbiomes as potential resistance gene sources with implications for agricultural, food, and human health safety.

China's massive reforestation effort has transformed more than 77 million hectares of land, but new research shows that planted forests face different drought risks from natural forests. Using satellite observations from 1990 to 2024 and machine learning analysis, researchers found that planted forests are more vulnerable to rapid-onset flash droughts but less prone to prolonged slow droughts. The differences are linked to forest structure: natural forests have greater species diversity, more complex canopies, and deeper root systems that help buffer sudden water shortages, while planted forests are typically younger and less diverse. The findings highlight a trade-off in drought resilience and suggest that future forest management should prioritize mixed-species, structurally diverse forests to better withstand increasing climate extremes.