Welcome to Acta Prataculturae Sinica ! Today is

Acta Prataculturae Sinica ›› 2026, Vol. 35 ›› Issue (9): 142-153.DOI: 10.11686/cyxb2025335

Previous Articles    

Biological characteristics and risk analysis of the alien invasive plant Pluchea sagittalis

Qiong ZHANG(), Yi-ya LI, Luan-mei LU, Zheng-bin CHEN, Li-xia ZHU   

  1. School of Biological Sciences and Biotechnology,Key Laboratory of Landscape Plant with Fujian and Taiwan Characteristics of Fujian Colleges and Universities,Minnan Normal University,Zhangzhou 363000,China
  • Received:2025-08-18 Revised:2025-11-03 Online:2026-09-20 Published:2026-07-27
  • Contact: Qiong ZHANG

Abstract:

The invasive alien plant Pluchea sagittalis is a perennial herb native to South America. This weed has been detected with increasing frequency across multiple regions across China in recent years, and has caused serious ecological harm in some areas. Because of its high reproductive capacity and rapid rate of spread, this species poses a significant invasion risk. In this study, we investigated the population characteristics, biomass allocation, flowering phenology, and seed germination of P. sagittalis through fixed-point field observations, and then conducted a quantitative analysis of its invasiveness. The overall aim of this research was to explore the ecological adaptation mechanisms and invasive potential of this invasive plant species to provide a scientific basis for the prevention and control of its spread. The results of the field observations show that P. sagittalis has a clumped distribution pattern. During the vegetative growth stage, the total plant biomass increases with plant height, following a highly significant exponential relationship (P<0.001). Notably, the stem accounts for the largest proportion of biomass (52.14% of total biomass), reflecting a rapid vertical growth strategy to occupy ecological niches and optimize light interception. Phenological observations in Zhangzhou, Fujian Province, revealed a prolonged flowering period from May to November, with peak flowering occurring in summer (June-August). Our observations revealed that a single capitulum completes development from bud emergence to seed maturation in 20-30 days. Analyses of its reproductive traits indicated that this plant has dual strategies: clonal propagation via lateral root expansion and outcrossing sexual reproduction with capitula bearing numerous fertile pistillate flowers on the periphery. Its pollen grains have distinctive conical spines (diameter: 20.19 μm) and are classified as starch-type pollen. The species is self-incompatible, requiring pollinator-dependent cross-fertilization. Seed germination assays demonstrated a natural germination rate of 20.33%. The invasion risk value for P. sagittalis was calculated as 68. According to the grading criteria of the technical specifications, the introduction of P. sagittalis should be strictly prohibited, and we recommend including it in the regulated control list. The combined traits of rapid growth, dual reproductive modes, and high dispersal efficiency collectively contribute to its strong invasive potential in subtropical ecosystems.

Key words: alien invasion plant, Pluchea sagittalis, growth characteristics, risk analysis