Implications of climate change for environmental niche overlap between fiveCuscutapest species and their two main Leguminosae host crop species

Abstract

Some parasitic plants are major pests in agriculture, but how this might be affected by climate change remains largely unknown. In this study, we assessed this for five generalist holoparasitic Cuscuta species (smoothseed alfalfa dodder (Cuscuta approximata Bab.), alfalfa dodder (Cuscuta europaea L.), soybean dodder (Cuscuta chinensis C. Wright), Peruvian dodder (Cuscuta australis R. Br.), Japanese dodder (Cuscuta japonica Choisy)) and two of their main Leguminosae host crop species (soybean [Glycine max (L.) Merr.] and alfalfa (Medicago sativa L.)). For each of the five Cuscuta species and the two crop species, we ran MaxEnt models, using climatic and soil variables to predict their potential current distributions and potential future distributions for 2070. We ran species distribution models for all seven species for multiple climate-change scenarios, and tested for changes in the overlap of suitable ranges of each crop with the five parasites. We found that annual mean temperature and isothermality are the main bioclimatic factors determining the suitable habitats of the Cuscuta species and their hosts. For both host species, the marginally to optimally suitable area will increase by 2070 for all four RCP scenarios. For most of the Cuscuta species, the marginally to optimally suitable area will also increase. As the suitable area for both the hosts and the parasites will overall increase, Schoener’s D, indicating the relative overlap in suitable area, will change only marginally. However, the absolute area of potential niche overlap may increase up to six-fold by 2070. Overall, our results indicate that larger parts of the globe will become suitable for both host species, but that they could also suffer from Cuscuta parasitism in larger parts of their suitable ranges.

Spatial weed distribution models under climate change: a short review

“…To combat weed success, it is encouraged to research and model native species used in crops that prevent their invasion as in the case of Ipomoea batatas (L.) Lam., and Vitex negundo L. in China ( Fang et al, 2021 ). In the same context, parasitic plant species must also be taken into account too, as has been supported by recent studies ( Cai et al, 2022 ).…”

“…The scientific community is responding well to concerns about weeds, agriculture, and climate change. Studies are being carried out around the world, and they are being steadily published ( Cai et al, 2022 ). Nonetheless, there is still a gap to be filled, depending on the weeds and the areas and crops that they colonize.…”

What explains the high island endemicity of PhilippineRafflesia? A species distribution modeling analysis of three threatened parasitic plant species and their hosts

“…A better understanding of the distribution, habitat requirements, and dispersal abilities of species can result in more effective conservation management plans (Bellard et al, 2012; Guisan et al, 2013; Driscoll et al, 2014; Cai et al, 2022). This includes identifying areas that should be prioritized for formal protection (e.g., Spiers et al, 2018).…”

“…Parasitic plants are considered particularly vulnerable to the effects of habitat destruction and climate change due to their obligate dependence on their host plants (Mkala et al, 2022). Yet, little attention has thus far been given to examining how their distribution ranges and those of their hosts might change under different climate change scenarios (Zamora and Mellado, 2019; Cai et al, 2022; Mkala et al, 2022; Renjana et al, 2022). This might be a result of the negative stereotype associated with parasitism, especially for species that are, correctly or incorrectly, considered noxious weeds (Costea and Stefanović, 2009), but there are also other reasons.…”

“…This might be a result of the negative stereotype associated with parasitism, especially for species that are, correctly or incorrectly, considered noxious weeds (Costea and Stefanović, 2009), but there are also other reasons. Accurately predicting distribution ranges is challenging for parasitic species for which host specificity information is sparse, because the distribution of parasites is limited by the geographic distribution and ecosystem requirements of their hosts (Costea and Stefanović, 2009; Cai et al, 2022). These same factors complicate effective conservation management of parasitic plants.…”