TY - JOUR
T1 - Biogeography of cereal stemborers and their natural enemies
T2 - forecasting pest management efficacy under changing climate
AU - Mutamiswa, Reyard
AU - Chikowore, Gerald
AU - Nyamukondiwa, Casper
AU - Mudereri, Bester Tawona
AU - Khan, Zeyaur Rahman
AU - Chidawanyika, Frank
N1 - Funding Information:
The authors gratefully acknowledge the financial support for this research by the following organizations and agencies: the Norwegian Agency for Development Cooperation (NORAD) project on Combating Arthropod Pest for Better Health, Food and Resilience to Climate Change (CAP‐AFRICA) grant number RAF‐3058 KEN‐18/0005; the Swedish International Development Cooperation Agency (SIDA); the Swiss Agency for Development and Cooperation (SDC); the Federal Democratic Republic of Ethiopia; and the Government of the Republic of Kenya. Valuable institutional support from University of the Free State (UFS) to RM, GC and FC, Botswana International University of Science and Technology (BIUST) and Rhodes University to CN as well as Midlands State University (MSU) to RM is highly appreciated. The views expressed herein do not necessarily reflect the official opinion of the donors.
Publisher Copyright:
© 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
PY - 2022
Y1 - 2022
N2 - Background: Climate warming presents physiological challenges to insects, manifesting as loss of key life-history fitness traits and survival. For interacting host–parasitoid species, physiological responses to heat stress may vary, thereby potentially uncoupling trophic ecological relationships. Here, we assessed heat tolerance traits and sensitivity to prevailing and future maximum temperatures for the cereal stemborer pests, Chilo partellus, Busseola fusca and Sesamia calamistis and their endo-parasitoids, Cotesia sesamiae and Cotesia flavipes. We further used the machine learning algorithm, Maximum Entropy (MaxEnt), to model current and potential distribution of these species. Results: The mean critical thermal maxima (CTmax) ranged from 39.5 ± 0.9°C to 44.6 ± 0.6°C and from 46.8 ± 0.7°C to 48.5 ± 0.9°C for parasitoids and stemborers, with C. sesamiae and Ch. partellus exhibiting the lowest and highest CTmax respectively. From the current climate to the 2050s scenario, parasitoids recorded a significant reduction in warming tolerance compared with their hosts. Habitat suitability for all stemborer–parasitoid species was spatially heterogeneous under current and future climatic scenarios. Cotesia sesamiae C. flavipes and B. fusca exhibited significant habitat loss, whereas Ch. partellus and S. calamistis showed a significant habitat gain under future 2050s predictions. Model metrics based on mean area under the curve ranged from 0.72 to 0.84 for all species, indicating a good predictive performance of the models. Conclusion: These results suggest C. sesamiae and C. flavipes may face survival constraints or extirpation compared with their pest hosts when environmental temperature reaches their upper thermal limits earlier, likely reducing pest regulation through density-mediated effects. The results demonstrate potential destabilization of stemborer–parasitoid trophic systems potentially compromising biocontrol efficacy under climate warming.
AB - Background: Climate warming presents physiological challenges to insects, manifesting as loss of key life-history fitness traits and survival. For interacting host–parasitoid species, physiological responses to heat stress may vary, thereby potentially uncoupling trophic ecological relationships. Here, we assessed heat tolerance traits and sensitivity to prevailing and future maximum temperatures for the cereal stemborer pests, Chilo partellus, Busseola fusca and Sesamia calamistis and their endo-parasitoids, Cotesia sesamiae and Cotesia flavipes. We further used the machine learning algorithm, Maximum Entropy (MaxEnt), to model current and potential distribution of these species. Results: The mean critical thermal maxima (CTmax) ranged from 39.5 ± 0.9°C to 44.6 ± 0.6°C and from 46.8 ± 0.7°C to 48.5 ± 0.9°C for parasitoids and stemborers, with C. sesamiae and Ch. partellus exhibiting the lowest and highest CTmax respectively. From the current climate to the 2050s scenario, parasitoids recorded a significant reduction in warming tolerance compared with their hosts. Habitat suitability for all stemborer–parasitoid species was spatially heterogeneous under current and future climatic scenarios. Cotesia sesamiae C. flavipes and B. fusca exhibited significant habitat loss, whereas Ch. partellus and S. calamistis showed a significant habitat gain under future 2050s predictions. Model metrics based on mean area under the curve ranged from 0.72 to 0.84 for all species, indicating a good predictive performance of the models. Conclusion: These results suggest C. sesamiae and C. flavipes may face survival constraints or extirpation compared with their pest hosts when environmental temperature reaches their upper thermal limits earlier, likely reducing pest regulation through density-mediated effects. The results demonstrate potential destabilization of stemborer–parasitoid trophic systems potentially compromising biocontrol efficacy under climate warming.
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U2 - 10.1002/ps.7062
DO - 10.1002/ps.7062
M3 - Article
AN - SCOPUS:85135093845
SN - 1526-498X
VL - 78
SP - 4446
EP - 4457
JO - Pest Management Science
JF - Pest Management Science
IS - 11
ER -