Effects of elevation and habitat on leaf and reproductive traits of Ageratina adenophora (Sprengel) King & Robinson

Elevational gradients as well as habitat variability provide variation in environmental conditions enabling plants to alter their functional traits with respect to their surroundings on the way to sustain and better perform. Phenotypic plasticity has been suggested as one of the foremost mechanisms that invasive species implement to endure and invade wide geographical areas. The present study was performed to understand the leaf functioning and reproductive approaches adopted by the invasive weed Ageratina adenophora in response to different habitats of Kumaun Himalaya along elevational ranges. ANOVA showed significant effects of elevational ranges, habitats and their interactions on most of the investigated traits. A wide range in leaf area (367-1278 cm(2)/plant) and seed number (2803-12,240 seeds/plant) across the elevational zones indicated high plastic responses. Linear regression analysis revealed that the specific leaf area (r =-0.279; p < 0.05) and leaf area ratio (r =-0.255; p < 0.05) decreased significantly with increasing elevation. Reproductive traits like seed number (r =-0.284; p < 0.05) and reproductive index (r =-0.416; p < 0.05) also decreased significantly with increasing elevation. The results revealed that this species responds to heterogeneous environments via altering its leaf traits and reproductive performance. The large differences in trait values between habitats and elevations suggested a high degree of plasticity, which is leading to the successful encroachment and establishment of A. adenophora across an elevational gradient without undergoing adaptive evolution. (c) 2022 SAAB. Published by Elsevier B.V. All rights reserved.