Rice is a staple food for nearly two-thirds of China’s population. As socio-economic development continues, there is a growing demand for high-quality rice. This study collected grain quality traits for 17,785 rice varieties approved throughout China, and categorized them into the following five types: indica inbred (II), indica hybrid (IH), japonica inbred (JI), japonica hybrid (JH), and indica-japonica hybrid (IJ). Comprehensive analyses were conducted to assess the differences and trends in rice quality across these varieties. We found that JI and JH excel in processing and cooking qualities, featuring higher brown rice and head milled rice rates, coupling with longer gel consistency. Inbred varieties display lower chalky rice rates than hybrids. Over several decades, head milled rice rates have notably increased across all types except for IJ. Transparency grade has decreased in nearly all types except for IJ, with similar declines observed in chalky rice rates and chalkiness degree, suggesting an overall progress in appearance quality. In terms of cooking and taste attributes, amylose content has decreased in most varieties except for IJ, and gel consistency has improved in indica varieties. Generally, the rice quality of varieties approved in China has shown a clear trend of improvement over the past 40 years. This study provides significant data support and theoretical backing for ongoing rice breeding efforts.

Invasive plant species are often characterized by superior resource acquisition capabilities compared with native species, contributing to their success in new environments. However, the dominance of these species varies, and not all invasive species become dominant, nor are all native species uniformly vulnerable to competitive exclusion. In this study, we analyzed 19 functional traits across 144 herbaceous plant species in Guangzhou, China. The studied species included 31 invasive dominant species (IDS), 19 invasive non-dominant species (INS), 63 native dominant species (NDS), and 31 native non-dominant species (NNS). Our findings reveal no significant differences in functional traits between IDS and INS, indicating a broad trait similarity within invasive categories. Pronounced similarities between invasive species and NDS suggest an ecological equivalency that facilitates successful integration and competition in new habitats. Notable differences in several key traits—height, leaf thickness, leaf water content, stoichiometry, photosynthetic rate, water use efficiency, and nitrogen use efficiency—indicate a competitive superiority in resource acquisition and utilization for invasive species over NNS. These distinctions are vital for understanding the mechanisms driving the success of invasive species and are crucial for developing strategies to manage their impact on native ecosystems.

Nitrogen (N) availability fundamentally shapes the community structure and competitive dynamics of floating macrophytes in paddy ecosystems. This study investigated the competitive interactions between Azolla and Lemna by applying a gradient of N concentrations (0–12 mg L⁻¹) across two experimental periods (November–January and March–May). Our results demonstrate a clear divergence in resource-use strategies between the two species: Azolla exhibited stronger stoichiometric homeostasis and a more conservative growth profile, retaining a competitive advantage under N-limiting conditions. Conversely, Lemna displayed a more opportunistic strategy, gaining a competitive advantage in N-rich environments through greater morphological plasticity and luxury nutrient uptake. This nitrogen-driven shift in competitive balance was associated with differences in root traits and stoichiometric flexibility. Stoichiometrically, Lemna exhibited greater flexibility in nutrient balance, including higher phosphorus accumulation under N-rich conditions, which may support rapid biomass expansion. Differences between the two experimental periods were also associated with variation in trait expression, suggesting that temporal context influenced how the two species responded to N enrichment. These findings highlight the importance of nitrogen management in steering floating-plant communities in paddy ecosystems: low-N inputs may help maintain Azolla-dominated communities with biofertilizer potential, whereas high-N conditions may favor Lemna and its rapid nutrient uptake.

Understanding why some plant species become widespread while others remain restricted to limited ranges is a central challenge in ecology and biogeography. This study investigates how functional traits, including morphological, physiological, and nutrient-related traits, relate to the global registrability—defined as the likelihood of a species being observed and recorded—for 144 herbaceous plant species from Guangzhou, China. We combined field-measured morphological, physiological, and nutrient-related traits with occurrence data from the Global Biodiversity Information Facility (GBIF), quantified as the number of unique 10 km × 10 km grid cells per species. Our analyses reveal that resource-acquisitive traits—such as high leaf water content, chlorophyll concentration, and photosynthetic capacity—are positively associated with registrability, whereas traits linked to nutrient conservation (e.g., high leaf carbon content and leaf carbon-to-nitrogen ratios) show negative associations. Principal component analysis further indicates that multivariate trait axes characterized by acquisitive strategies are significantly and positively associated with higher registrability. These findings suggest that species with fast-growth, resource-intensive strategies are more likely to be encountered and reported, potentially due to both ecological generalism and observation bias.