Designing of future ornamental crops: a biotechnological driven perspective

Cytogenetic analysis and visualization of genetic relationships in wild lilies

Lilies are highly regarded for their ornamental appeal and striking flowers, which are of significant importance in horticulture. Understanding the genetic makeup of these plants is crucial for breeding and developing new cultivars. This study presents a comprehensive cytogenetic analysis of 45 S and 5 S rDNA loci in 34 wild Lilium species. To reveal the genetic relationships within the genus, advanced visualization methods, such as heatmaps and 3D network plots, were utilized. The results of this study identified both conserved and divergent genetic features, which offer insights into the evolutionary history and potential genetic compatibility of these species. Notably, the clustering of species based on rDNA locus patterns highlights the need for potential taxonomic re-evaluation and reveals candidates for cross-breeding. This integrated approach emphasizes the importance of combining cytogenetic data with traditional morphological classifications to refine our understanding of the Lilium species. Future research should expand the range of analyzed species, incorporate additional molecular markers to further elucidate genetic relationships, and support the development of resilient and diverse ornamental crops. The findings of this study provide a novel framework for genetic analysis of Lilium, offering valuable insights for both scientific understanding and practical breeding programs.

Engineered dsRNA-protein nanoparticles for effective systemic gene silencing in plants

Long-distance transport or systemic silencing effects of exogenous biologically active RNA molecules in higher plants have not been reported. Here, we report that cationized bovine serum albumin (cBSA) avidly binds double-stranded beta-glucuronidase RNA (dsGUS RNA) to form nucleic acid-protein nanocomplexes. In our experiments with tobacco and poplar plants, we have successfully demonstrated systemic gene silencing effects of cBSA/dsGUS RNA nanocomplexes when we locally applied the nanocomplexes from the basal ends of leaf petioles or shoots. We have further demonstrated that the cBSA/dsGUS RNA nanocomplexes are highly effective in silencing both the conditionally inducible DR5-GUS gene and the constitutively active 35S-GUS gene in leaf, shoot, and shoot meristem tissues. This cBSA/dsRNA delivery technology may provide a convenient, fast, and inexpensive tool for characterizing gene functions in plants and potentially for in planta gene editing.

Genome and GWAS analysis identified genes significantly related to phenotypic state of Rhododendron bark

As an important horticultural plant, Rhododendron is often used in urban greening and landscape design. However, factors such as the high rate of genetic recombination, frequent outcrossing in the wild, weak linkage disequilibrium, and the susceptibility of gene expression to environmental factors limit further exploration of functional genes related to important horticultural traits, and make the breeding of new varieties require a longer time. Therefore, we choose bark as the target trait which is not easily affected by environmental factors, but also has ornamental properties. Genome-wide association study (GWAS) of Rhododendron delavayi (30 samples), R. irroratum (30 samples) and their F1 generation R. agastum (200 samples) was conducted on the roughness of bark phenotypes. Finally, we obtained 2416.31 Gbp of clean data and identified 5 328 800 high-quality SNPs. According to the P-value and the degree of linkage disequilibrium of SNPs, we further identified 4 out of 11 candidate genes that affect bark roughness. The results of gene differential expression analysis further indicated that the expression levels of Rhdel02G0243600 and Rhdel08G0220700 in different bark phenotypes were significantly different. Our study identified functional genes that influence important horticultural traits of Rhododendron, and illustrated the powerful utility and great potential of GWAS in understanding and exploiting wild germplasm genetic resources of Rhododendron.