Effects of stolon severing on the expansion of Alternanthera philoxeroides from terrestrial to contaminated aquatic habitats

摘要: Few studies have examined the effects of clonal integration (translocation resources between interconnected ramets) during expansion amphibious plants from terrestrial to aquatic habitats. We conducted a greenhouse experiment simulate contaminated habitats in stoloniferous herb Alternanthera philoxeroides (alligator weed). The proximal ramets (i.e. relatively old) fragments grown uncontaminated soils were connected (allowing integration) or disconnected (preventing distal young) either water (control, no CuSO4) four copper-contaminated treatments containing 31.25, 62.5, 125 and 250 mg/L CuSO4, respectively. When stolon connection was severed, all died. intact, however, survival rate 85–100% when they at three lower levels contamination 43.75% highest level. Moreover, growth did not differ those control (uncontaminated water). These results suggest that could greatly improve alligator weed subjected moderate copper stress. Although also increase level stress (250 mg/L compared with ramets, measures still significantly than control. This suggests plays limited role it is severe by high contamination.