Growth analysis of a reestablished population versus a natural population of Bidens cernua L.

Abstract

A reintroduction experiment of Bidens cernua L., a species included in the Red List of Italian Flora, was carried out at Lake Posta Fibreno (Lazio, central Italy). There were no significant differences in the length of the phenological phases between the reestablished population (P_r) and the natural one (P_n). The length of the phenological cycle, from seedling emergence to the end of the fruiting phase, was 207 ± 3 days. The relative growth rate in height (RGR_H) and relative growth rate in mass (RGR_m) were significantly (p < 0.05) higher for P_r (0.047 ± 0.001 cm cm⁻¹ d⁻¹ and 0.057 ± 0.001 g g⁻¹ d⁻¹, respectively) than for P_n (0.045 ± 0.001 cm cm⁻¹ d⁻¹ and 0.055 ± 0.001 g g⁻¹ d⁻¹, respectively). There were significant (p < 0.05) differences for plant height (H) and total leaf area per plant (TLA) between P_r and P_n, the latter having the lower values. Total plant dry mass (PDM) was significantly higher for P_r, and the above‐ground/below‐ground dry mass ratio was 6.7 ± 0.4 and 4.7 ± 0.2 for P_r and P_n, respectively. On the whole, results demonstrate that the P_r of B. cernua has the potential to develop in a manner that is demographically similar to the P_n present in the Posta Fibreno Lake protected area.

Abbreviations: H, plant height; LA, mean leaf area; LM, leaf dry mass; PCA, principal component analysis; PDM, total plant dry mass; P_n, natural population; P_r, reestablished population; RGR_H, relative growth rate in plant height; RGR_m, relative growth rate in plant dry mass; SLA, specific leaf area; TLA, total leaf area per plant

Keywords:

• Bidens cernua L.
• phenology
• relative growth rate
• seed yield
• total leaf area
• total plant dry mass