title: Weeds in a Changing Climate: Vulnerabilities, Consequences, and Implications for Future Weed Management.
abstract: Whilst it is agreed that climate change will impact on the long-term interactions between crops and weeds, the results of this impact are far from clear. We suggest that a thorough understanding of weed dominance and weed interactions, depending on crop and weed ecosystems and crop sequences in the ecosystem, will be the key determining factor for successful weed management. Indeed, we claim that recent changes observed throughout the world within the weed spectrum in different cropping systems which were ostensibly related to climate change, warrant a deeper examination of weed vulnerabilities before a full understanding is reached. For example, the uncontrolled establishment of weeds in crops leads to a mixed population, in terms of C3and C4pathways, and this poses a considerable level of complexity for weed management. There is a need to include all possible combinations of crops and weeds while studying the impact of climate change on crop-weed competitive interactions, since, from a weed management perspective, C4weeds would flourish in the increased temperature scenario and pose serious yield penalties. This is particularly alarming as a majority of the most competitive weeds are C4plants. Although CO2is considered as a main contributing factor for climate change, a few Australian studies have also predicted differing responses of weed species due to shifts in rainfall patterns. Reduced water availability, due to recurrent and unforeseen droughts, would alter the competitive balance between crops and some weed species, intensifying the crop-weed competition pressure. Although it is recognized that the weed pressure associated with climate change is a significant threat to crop production, either through increased temperatures, rainfall shift, and elevated CO2levels, the current knowledge of this effect is very sparse. A few models that have attempted to predict these interactions are discussed in this paper, since these models could play an integral role in developing future management programs for future weed threats. This review has presented a comprehensive discussion of the recent research in this area, and has identified key deficiencies which need further research in crop-weed eco-systems to formulate suitable control measures before the real impacts of climate change set in.
authors.affiliation: Indian Council of Agricultural Research - Indian Institute of Soil Science Bhopal, India.
authors.forename: Kulasekaran
authors.initials: K
authors.lastname: Ramesh
authors.affiliation: Department of Agronomy, Muhammad Nawaz Shareef University of AgricultureMultan, Pakistan; The Centre for Plant Science, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, ToowoombaQLD, Australia.
authors.forename: Amar
authors.initials: A
authors.lastname: Matloob
authors.affiliation: Department of Agronomy, University of AgricultureFaisalabad, Pakistan; Ayub Agricultural Research InstituteFaisalabad, Pakistan.
authors.forename: Farhena
authors.initials: F
authors.lastname: Aslam
authors.affiliation: Centre for Environmental Management, Faculty of Science and Technology, Federation University Australia, Mount Helen VIC, Australia.
authors.forename: Singarayer K
authors.initials: SK
authors.lastname: Florentine
authors.affiliation: The Centre for Plant Science, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Toowoomba QLD, Australia.
authors.forename: Bhagirath S
authors.initials: BS
authors.lastname: Chauhan
keywords: agricultural; climate change; crops; management crop; vulnerabilities; weed