Genome size, the total amount of DNA content in the cell nucleus, varies greatly among flowering plants. One factor underlying this variation is the environment under which plants evolve. Given this premise, harsh environmental conditions in arid regions may profoundly influence genome evolution. However, the specific impact of aridification on genome size evolution, particularly for African lineages, remains largely unexplored. Here, we investigate linkages between genome size evolution and ecological adaptation using the genus Cyphostemma in the grape family (Vitaceae) as a model. Cyphostemma species exhibit genome size expansion and remarkable morphological traits in arid environments, including succulent stems or leaves and loss of tendrils. Our biogeographic reconstruction, based on substantial taxon sampling (112 of 200 species), reveals that Cyphostemma originated in continental Africa during the late Eocene to Oligocene and has undergone rapid radiation since the middle Miocene, coinciding with intensified aridification and geological activity in eastern Africa. Incorporating extensive data on traits, habitats, genome size, and chromosome numbers, we show that Cyphostemma species with the largest genomes are succulent polyploids restricted to nutrient-rich limestone outcrops. Broad-scale analyses across eudicots further confirm that larger genomes are significantly associated with both succulence and arid habitats. Our findings reveal a strong association between genome size expansion, polyploidy, and adaptive traits, indicating that genome size is a hitherto neglected trait associated with the radiation of succulent plants during the African aridification in the Cenozoic.

Hidden hunger, caused by chronic micronutrient deficiencies, affects billions of people worldwide and remains a critical public health issue despite progress in food production. Biofortification offers a promising solution by enhancing nutrient levels within plant tissues through traditional breeding or advanced biotechnologies. Recent advancements in plant synthetic biology have significantly improved biofortification strategies, enabling precise and targeted nutrient enrichment. This mini-review outlines five core strategies in synthetic biology-based biofortification: overexpression of endogenous biosynthetic genes, introduction of heterologous biosynthetic pathways, expression of nutrient-specific transporters, optimization of transcriptional regulation, and protein (directed) evolution. Vitamin B₁ biofortification serves as a primary illustrative example due to its historical importance and ongoing relevance. Recent breakthroughs, particularly from Chinese research teams, are also highlighted. Together, these strategies offer transformative potential for addressing global nutritional challenges through precise, sustainable and innovative plant-based approaches.

Plants have evolved a remarkable ability to sense and respond to changes in photoperiod, allowing adjustments to their growth and development based on seasonal and environmental cues. The floral transition is a pivotal stage in plant growth and development, signifying a shift from vegetative to reproductive growth. CONSTANS (CO), a central photoperiodic response factor conserved in various plants, mediates day-length signals to control the floral transition, although its mechanisms of action vary among plants with different day-length requirements. In addition, recent studies have uncovered roles for CO in organ development and stress responses. These pleiotropic roles in model plants and crops make CO a potentially fruitful target for molecular breeding aimed at modifying crop agronomic traits. This review systematically traces research on CO, from its discovery and functional studies to the exploration of its regulatory mechanisms and newly discovered functions, providing important insight into the roles of CO and laying a foundation for future research.