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bioRxiv · 10.1101/2021.10.01.462801

Potential of breadfruit cultivation to contribute to climate-resilient low latitude food systems

Abstract

The number of people in food crisis around the world is increasing, exacerbated by the challenges of COVID-19 and a rapidly changing climate. Major crop yields are projected to decrease in low-latitude regions due to anthropogenic climate change, making tropical and sub-tropical food systems particularly vulnerable to climate shocks. Increased cultivation of breadfruit (Artocarpus altilis), often categorized as a neglected and underutilized species (NUS), has been suggested as an agricultural adaptation pathway for food insecure tropical and subtropical regions, due to its potential to enhance climate resilience and overall sustainability of low-latitude agricultural systems. To better understand breadfruits cultivation suitability and geographic range in current and future climates, we employ a diverse set of observations and models to delineate the current climatically viable breadfruit range and assess the climatically viable breadfruit range in the future (2061-2080) under stabilization and high emission scenarios. We find that the area of suitable breadfruit range within the tropics and subtropics is projected to decrease ~4.4% in the stabilization scenario and ~4.5% in the high emission scenario. In Southeast Asia and the Pacific Islands, yield quality and consistency show minimal decreases under the high emission scenario, with increases in total suitable area under both scenarios. In contrast, in Latin America and the Caribbean, the current range of breadfruit suitability is projected to contract ~10.1-11.5% (stabilization-high emission). Present and future model suitability outputs suggest that opportunities to successfully expand breadfruit cultivation over the next several decades exist in sub-Saharan Africa, where food insecurity is coincidentally high. However, in all regions, high emission scenario conditions reduce the overall consistency and quality of breadfruit yields compared to the stabilization scenario. Our results have the potential to inform global food security adaptation planning and highlight breadfruit as an ideal NUS to incorporate in food security adaptation strategies in a changing climate.

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BibTeXRIS

Yang, L., Zerega, N., Horton, D. E.. 2021-10-01. Potential of breadfruit cultivation to contribute to climate-resilient low latitude food systems. https://doi.org/10.1101/2021.10.01.462801

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