Drought-tolerant peanut (Arachis hypogaea L.) varieties can mitigate negative impacts of climate change on yield in the Southeastern U.S.

Rising temperatures and varying precipitation patterns in future climates pose huge challenges to the peanut (Arachis hypogaea L.) production in Southeastern U.S. (SEUS), which was characterized by hot summers and mild winters. This will require genetic improvement of peanut varieties for adapting to future climates for higher yields. Recently, several novel peanut varieties were found to exhibit higher yield and maintain photosynthesis during drought. Thus, this study aimed to investigate the spatial and temporal patterns of peanut yield response to future climate changes for peanut varieties with and without the drought tolerant trait of maintaining photosynthesis (MPh) under drought in the SEUS and evaluate the relative importance of yield related traits for enhancing yield advantage of peanut under future climate conditions. A modified version of the CROPGRO-Peanut model incorporating the drought tolerant factor was developed and validated using field trail data collected from distinct experimental sites under both rainfed and irrigated conditions. Yield was then simulated for the historical baseline period (1990–2021) and future (mid-century/2050s, late-century/2080s) climate scenarios across the SEUS. The results showed that peanut yield in the Northern SEUS was expected to benefit from climate change in the 2050s (RCP4.5 and RCP8.5), but Middle SEUS and Southern SEUS would experience high probability of yield loss in the future. Comparing to the reference variety (C4), the drought tolerant peanut varieties (C1, C2 and C3) with the trait of MPh under drought could enhance the yield gains due to future climates in the 2050s (RCP4.5 and RCP8.5) in Northern SEUS (yield increases from 5% to 10% for C1-C3, and 2% to 3% for C4) and mitigate the negative impacts of climate change in the 2080s (RCP4.5 and RCP8.5) in the Middle (yield changes from −26% to −1% for C1-C3, and −37% to −11% for C4) and Southern SEUS (yield changes from −24% to 1% for C1-C3, and −35% to −7% for C4). The yield advantage of the drought tolerant peanut varieties in future climates was strongly associated with the higher water use efficiency (WUE), harvest index (HI), seed size, seed number, and biomass with significant P values (p < 0.001). These findings are important for local breeding and management programs to mitigate the potential impacts of climate change on peanut yield in SEUS.