Indian sugarcane under warming climate: A simulation study

Abstract

Multi-model climate projections are increasingly used to quantify the impacts of climate change on major staple crops under different climate change scenarios. Despite uncertainty associated with different climate projections, it helps in providing a direction and magnitude of change in crop production in future with different uncertainty levels. In this study, we used the CANEGRO-Sugarcane crop model driven by downscaled and bias-corrected simulations forced by different regional climate models (RCMs) for the mid-future (2040–2069) and far-future (2070–2099) under the two emission scenarios RCP4.5 and RCP8.5 to simulate the effect of climate change on sugarcane’s stalk fresh mass (SFM) and Sucrose Mass (SM) over major sugarcane growing states of India. The result showed, out of three phenological phases analyzed, two were found to be Shortened (planting to emergence up to 14.5 days and emergence to stalk elongation up to 6.3 days) and one i.e., peak population to harvest get extended up to 9.5 days under RCP8.5, far-future. An increase in SFM is projected substantially in the mid-future under RCP 8.5 for the tropical state of Gujarat (11.2–18.1 %) and the least for Odisha (6.8 % to 10.7). On the contrary, SM was found to decrease overall except for the states of Uttar Pradesh, Maharashtra, Gujrat, and Andhra Pradesh. The changes in the SFM and SM were found to be regulated by the increase in maximum (Tmax) and minimum temperature (Tmin), decline in solar radiation (Srad), leading to an increase in SFM and a reduction in sugar content. Therefore, decline in SM in the future which may cause economic loss as sugarcane is one of the most important cash crops of India. With uncertainties in the magnitude of change, the findings are useful for plant breeders and policymakers to develop appropriate strategies to minimize the loss and enhance sugar production.