Trait variability in co-occurring invasive and native plant species in road side population of Kumaun Himalaya

• Published in: Revista brasileira de botânica 2022-09, Vol.45 (3), p.1099-1110
• Main Authors: Khatri, Kavita, Negi, Bhawna, Bargali, Kiran, Bargali, Surendra Singh
• Format: Article
• Language: English
• Subjects: Biohazards; Biomass; Biomedical and Life Sciences; Botany; Dry matter; Ecology & Biogeography - Original Article; Flowers & plants; Indigenous plants; Indigenous species; Introduced species; Invasive plants; Invasive species; Leaf area; Leaves; Life Sciences; Plant species; Plant Systematics/Taxonomy/Biogeography; Plants (botany); Reproduction; Resource allocation; Resource conservation; Roadsides; Soil properties; Strategy; Water stress
• ISSN: 1806-9959; 0100-8404; 1806-9959
• DOI: 10.1007/s40415-022-00827-y

Since coexisting invasive and native plant species are exposed to similar environmental circumstances and selection pressures, variation in the morpho-functional, resource allocation and reproductive performance of these species could reflect the strategies adopted by the former for their invasion success. This study observed general differences in the morphological and physiological traits between invasive Ageratina adenophora and its co-occurring other invasive ( Bidens pilosa ) and native ( Galinsoga ciliata ) aster species in roadside populations of Kumaun Himalayan region. Plant samples were collected during their peak growth period. For the collection of plant and soil samples, five plots of 50 m × 2 m size were established at regular interval on the Nainital–Kathgodam road between 1800 and 1900 m asl. Five quadrats of 1 m × 1 m size were randomly placed at each of these plots, and from these quadrat, five individuals of each species were randomly collected. Soil was collected from 0 to 15 cm depth from all the five study plots. The results showed that soil properties did not vary among study plots and were of same nature. A. adenophora showed higher plant height and total biomass than its neighboring species and allocated more biomass to stem (76%) than G. ciliata (44%) and B. pilosa (38%) which reflects the competitive superiority of this plant over nearby vegetation for light harvesting. In contrast, highest biomass to leaves was allocated by G. ciliata (27%) followed by B. pilosa (26%) and A. adenophora (6%). The root/shoot ratio was lowest in A. adenophora and highest in B. pilosa . Specific leaf area was reported least for A. adenophora , while specific leaf weight was maximum reflecting the strategy of A. adenophora to survive in water stress conditions. High leaf dry matter content represented the physical strength and conservative strategy of A. adenophora in addition to protection from natural and biological hazards, whereas the highest seed number and reproductive index represented the superior reproductive efficiency than its co-occurring two species. Plant functional traits were positively or negatively correlated with each other and did not always exhibit higher values for A. adenophora . These findings suggest that A. adenophora possess superior traits associated with resource acquisition and resource conservation strategies in addition to advanced reproductive performance, which strongly influence the invasive success of this plant in