Morphological adaptation strategy of invasive plant Ambrosia trifida seed distributed along rivers is closely related to soil nutrients

• Published in: Plant diversity Vol. 47; no. 3; pp. 499 - 510
• Main Authors: Xu, Yufeng, Xue, Chenyang, Wang, Xuezhi, Meng, Lin, Gao, Ying, Yu, Mengyang, Geng, Lin, Shao, Meini, Qu, Bo
• Format: Journal Article
• Language: English
• Published: China Elsevier B.V 01.05.2025; Kunming Institute of Botany, Chinese Academy of Sciences
• Subjects: Ambrosia trifida; Biological invasion; gene flow; genes; Genetic differentiation; invasive species; maternal effect; nitrogen; organic matter; phosphorus; potassium; Research Paper; River; river water; rivers; seed dispersal; Seed morphology; seed weight; soil; species diversity; total nitrogen; water quality; River; Biological invasion; Genetic differentiation; Seed morphology
• ISSN: 2468-2659; 2096-2703; 2468-2659
• DOI: 10.1016/j.pld.2024.10.005

Rivers are crucial in the spread of invasive plants. Invasive plants alter their seed traits to adapt to environmental changes and promote invasion. Studying the trait changes in invasive plant seeds may improve the understanding of their propagation mechanisms along the river and provide appropriate control measures. In this study, seven Ambrosia trifida populations along the Liaohe River were used as study subjects. The results showed that the seven A. trifida populations were closely related and exhibited a certain gene exchange, but the absence of evidence of directed gene flow among populations did not confirm that rivers were the medium of seed dispersal of A. trifida. Along the Liaohe River, from top to bottom, the positive view area, length, width, perimeter, and thousand seed weight of A. trifida seeds showed an increasing trend. The total nitrogen and phosphorus contents in the river water of the A. trifida population in the lower reaches of the Liaohe River were higher than those at the other sites. Furthermore, along the river, from top to bottom, the available nitrogen, total nitrogen, total potassium, available potassium, and organic matter contents in the soil in which A. trifida populations grew showed significant increasing trends. River structure, water quality, and soil nutrients had direct and indirect effects on seed morphology. Soil total nitrogen, available potassium, and organic matter had significant positive effects on seed positive view area and perimeter, suggesting that the maternal effect played a critical role in shaping seed morphology. Our analysis showed that soil nutrients along the river may be the primary driver that governs changes in A. trifida seed traits. •Gene exchange exists among populations of Ambrosia trifida in Liaohe River.•The absence of direct evidence to confirm that rivers is the medium of seed dispersal of A. trifida.•River structure and water quality had direct and indirect effects on seed morphology, but not significant.•Soil nutrients had significant positive effects on seed morphology.