Climate resilience, yield and geographical suitability of sweet potato under the changing climate: A review

Sweet potato is one of the important tropical tuber crops across the world. This review analyzes the studies on the climate resilience of sweet potato to various environmental parameters, the impact of climate change on its yield, and geographical suitability to exploit more about this crop and find out the knowledge gap in its existing research. Drought tolerance studies indicate the suitability of sweet potato in drought-prone areas in terms of their survival rate, and their leaves can tolerate up to a wilting point of -1.3 MPa. The optimum night and daytime temperatures for sweet potato are 18 & DEG;C and 28 & DEG;C. There are 82 crop varieties available globally with heat-stress tolerance without compromising the yield. The elevated atmospheric CO2 enhanced the growth and yield of sweet potato and increased the water use efficiency. The salinity tolerance of sweet potato is observed as 11 dS m(-1), and it is superior to other major food crops. Sweet potato's ozone tolerance is higher than other crops (59 ppb). The impact studies on crop yield and geographical suitability also recommend its superiority to other major food crops with similar crop duration. As an outcome of this study, further research is needed to explore this crop as sweet potato can substitute for major food grain crops in developing countries regarding food, feed, medicine, and fuel. Research on value-added products and their marketing is another area that needs immediate attention. Studies must exploit sweet potato leaves to ensure nutritional security in developing countries. The researchers also need to focus on developing climate-resilient varieties to ensure a continuous supply of planting materials to needy people to ensure food security. This review also demands more studies on the modeling of sweet potato worldwide to issue crop yield forecasts and monitor the spatial distribution of its major pests worldwide.