Progress and challenges of rice ratooning technology in Anhui Province, China

Ratoon rice cultivation has expanded to improve resource use efficiency, increase economic profits, and ensure food security in China in recent years. This article reviewed the development history and research progress of ratoon rice in Anhui Province, located in the lower reaches of the Yangtze River. Key cultivation technologies related to rice variety selection, planting patterns, fertilizer and water management strategies, as well as harvesting methods and stubble heights of the main crop for high-yielding ratoon rice were summarized. Particularly, we described three types of rice ratooning technologies in Anhui, including the technologies for medium-duration indica hybrid variety with the main crop harvested mechanically at high stubble height, for indica-japonica hybrid variety with the main crop harvested mechanically at medium stubble height, and for short-duration indica variety with the main crop harvested mechanically at low stubble height. Additionally, this review analyzed several challenges for the sustainable development of ratoon rice in Anhui, such as poor understanding of mechanisms underlying simultaneous improvement of high yield and high quality, the lack of rice varieties with strong ratooning ability, the yield loss from mechanical harvesting of the main crop, the unstable grain yield due to adverse weather, and the insufficient financial support for R&D. Finally, the prospects for further development of ratoon rice were proposed, including technology development and dissemination, farmers' training, and profit-boosting from premium products.