A superweed in the making: adaptations of Parthenium hysterophorus to a changing climate. A review

Parthenium weed (Parthenium hysterophorus L.) is a globally invasive plant with significant negative impacts on the environment, agriculture, economy, and health. This invasion problem likely to be exacerbated by climate change. Elevated atmospheric carbon dioxide concentration ([CO2]), high ambient temperatures, heatwaves, droughts will facilitate establishment, range expansion, interference potential of this species while making its management more difficult. Here, for first time, we review impact change elements parthenium biology at regional global levels. We establish that (1) plants morphologically physiologically adapt sustain or promote their growth, fecundity, competitive ability, allelopathic effect under most scenarios; (2) can reduce relative vigor neighboring plants, especially C4 grasses, in competition weed, providing edge; (3) elevated [CO2] has pronounced positive performance compared other elements; (4) efficacy widely used herbicide, glyphosate, may reduced grown [CO2]; (5) mixed effects have been reported biological control agents, some losing ground, others are maintaining improving efficacy; (6) greater risk spread expansion sustained pose challenges natural managed ecosystems. There disturbing transition from noncropped landscapes agroecosystems response recent climatic land use changes. All evidence presented suggests situation greatly aggravated if drastic interventions not implemented. Therefore, research, policy, outreach focus must revisited revamped considering develop pragmatic solutions combat “superweed”.