Prospects for cotton self-sufficiency in China by closing yield gaps

Although China is the world second largest cotton (Gossypium hirsutum L.) producer, it is the world largest cotton consumer with high reliance on import. Cotton cropping system in China underwent substantial changes in the past few decades as 85% of the previous cotton area changed into other uses, and its production center has shifted fast to new croplands in Xinjiang where farm size is larger and mechanization more prevalent. Given these rapid changes, we performed the first comprehensive assessment of cotton production capacity and selfsufficiency ratio in China based on the analysis of yield gap (difference between current farm yield and yield potential) by employing a bottom-up scaling approach which entails local weather, soil, crop management and latest high-yielding experimental data. We found that current yield gap represents 40% of estimated potential yield, suggesting a large scope for total production increase by yield gap closure. China's current cotton selfsufficiency ratio is 68%, and it could reach 90% by yield gap closure in Xinjiang alone and up to 94% in all major cotton growing provinces by 2030. Results also highlight the regions with the greatest prospect for further production increase in China by considering current yield gaps, production area, and potential for expansion. Xinjiang alone could achieve 71% of additional production, while opportunities also exist in the other major cotton growing provinces, i.e., south part of Hebei and southeast part of Hubei provinces.