Xanthoceras sorbifolia is a unique woody oilseed tree in China, and its leaves are rich in flavonoids, which are involved in plant growth, development and defense. However, the mining of flavonoid synthesis-related genes in Xanthoceras sorbifolia leaves is lacking. In this study, 226 leaves of Xanthoceras sorbifolia from eight provinces in the key distribution areas were measured for flavonoid content, and the differences in flavonoid content of Xanthoceras sorbifolia were analysed to screen out excellent seed sources and six excellent single plants with higher flavonoid content. Genome-wide association analysis (GWAS) was used to identify genes controlling the synthesis of flavonoids, and 62 significant Single nucleotide polymorphism (SNP) sites were identified, which were closely associated with 8 traits, and a total of 11 genes coding for proteins. We found that these genes mainly encode proteins such as WPP domain-associated protein (WAP) (Fragment), Protein pleiotropic regulatory locus 1 (PRL1) and Phosphomevalonate kinase, peroxisomal (PMK), etc. We found that these proteins may directly or indirectly affect the synthesis of flavonoids, which will provide a data base for molecular breeding and genetic improvement of Xanthoceras sorbifolia.

Objectives: Toona sinensis, commonly known as Chinese toon, is a perennial woody plant with significant economic and ecological importance. This study employed whole-genome resequencing of 180 T. sinensis samples collected from Shandong to analyze genetic variation and diversity, ultimately identifying 18,231 high-quality SNPs after rigorous quality control and linkage disequilibrium pruning. This comprehensive genomic resource provides novel insights into the genetic architecture of T. sinensis, facilitating the elucidation of population structure and supporting future breeding programs. Data description: We performed whole-genome resequencing on 180 Toona sinensis samples, generating 1170.26 Gbp of clean data with a Q30 percentage of 93.69%. The average alignment rate to the reference genome was 96.72%, with an average coverage depth of 8 × and a genome coverage of 88.71%. Following data quality control and alignment, we performed SNP calling and filtering to identify high-quality SNPs across all samples. Population structure analyses were then conducted using the identified SNPs, including principal component analysis (PCA), structure analysis, and phylogenetic tree construction. These comprehensive analyses provide a foundation for understanding the genetic diversity and evolutionary dynamics of T. sinensis.

Xanthoceras sorbifolium Bunge, a unique oil crop native to northern China, has a long history of cultivation. In this study, X. sorbifolium Bunge was continuously planted in Zibo and Weifang, Shandong Province, to explore the factors that cause a decline in X. sorbifolium Bunge yield and fruit quality after long-term continuous planting. The results showed that the continuous cropping of X. sorbifolium Bunge led to a significant decrease in the biomass of the plant's seedlings, markedly reduced the root activity, and reduced the soil nutrient content. A significant change in the soil microbial community structure was observed after years of X. sorbifolia Bunge monoculture. At the genus level, the relative abundance of soil pathogenic fungi, such as Neocosmospora, Aspergillus, and Penicillium, significantly increased after continuous cropping, with the relative abundance of Neocosmospora increasing significantly in the three study sites. The abundance of common soil bacterial genera, such as Mortierella, Bacillus, and Streptomyces, is significantly lower under continuous cropping than in regular soil. The number of soil-specific bacteria was also reduced. The results showed that the accumulation of fungal pathogens, particularly Neocosmospora, may be the main challenge in the continuous cropping of X. sorbifolium Bunge, as it reduces the abundance of beneficial bacteria, primarily Bacillus, Streptomyces, and Mortierella.

Yellowhorn (Xanthoceras sorbifolium Bunge) is a woody oil species endemic to China. Its oil is predominantly composed of unsaturated fatty acids (UFAs, 85&