Sulphur cinquefoil (Potentilla recta L.) is an invasive plant of concern within grasslands in western North America. To better understand the role of native plant communities and soil seedbank in P. recta invasion within grasslands, we conducted two greenhouse studies to examine (1) P. recta growth response when grown with and without fertilizer in established native plant communities of varying functional groups (grasses, forbs, or grasses and forbs), and (2) the prevalence of P. recta and other species in the soil seedbank at varying soil depths (0 to 5 cm, 5 to 10 cm, 10 to 15 cm) of grasslands invaded by P. recta in southeastern British Columbia, Canada. The growth response of P. recta did not differ between the native plant communities. However, P. recta above- and belowground biomass declined as native plant aboveground biomass increased, suggesting a productive plant community may be important to suppress P. recta. Fertilizer did not affect the growth response of P. recta or native plants, suggesting nutrients may not have been a dominant limiting factor under greenhouse conditions. Nine species were identified in the soil seedbank. Seven were nonnative, which included P. recta, and native species represented less than 2% of the seedbank. Of the average number of emerged nonnative seedlings, more than 20% were P. recta. The number of emerged P. recta seedlings was 69% lower at 10- to 15-cm compared with 0- to 5-cm soil depth, although the successful germination of P. recta at greater soil depths suggests viable P. recta seeds are persisting in the seedbank. Active revegetation may be an important strategy to mitigate P. recta reinvasion or secondary invasion by other invasive species from the soil seedbank.

硫磺花 ( Potentilla recta L.) 是北美西部草原上令人担忧的入侵植物。为了更好地了解原生植物群落和土壤种子库在草原内直肠菌入侵中的作用，我们进行了两项温室研究，以检查 (1)在已建立的具有不同功能组的原生植物群落中，使用和不使用肥料生长的直肠菌生长反应（草、杂草或草和杂草），以及 (2) 草地不同土壤深度（0 至 5 厘米、5 至 10 厘米、10 至 15 厘米）的土壤种子库中P.recta和其他物种的流行率在加拿大不列颠哥伦比亚省东南部被P.recta入侵。P.recta的生长反应原生植物群落之间没有差异。然而，随着原生植物地上生物量的增加， P.recta地上和地下生物量下降，这表明生产性植物群落可能对抑制P.recta很重要。肥料不影响P.recta或本地植物的生长反应，这表明在温室条件下，养分可能不是主要的限制因素。在土壤种子库中鉴定出九种。七个是非本地的，其中包括P.recta，本地物种占种子库的不到 2%。在平均出苗数中，超过 20% 是P. recta。出现的P. recta数量与 0 至 5 厘米土壤深度相比，10 至 15 厘米的幼苗降低了 69%，尽管P.recta在更大土壤深度的成功发芽表明可行的P.recta种子持续存在于种子库中。积极的植被恢复可能是减轻土壤种子库中其他入侵物种重新入侵或二次入侵的重要策略。