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

Abstract

As the largest rice production province in China, the ratoon rice in Hunan has rapidly developed in recent years in the aspects of planting area, total production, and cultivation technologies. The present review is undertaken to summarize the past and current status and the key practices of ratoon rice production in Hunan. The planting area of ratoon rice in Hunan was 267,000 ​ha in 2019, with the average yield of 7.50–10.50 ​t ​ha⁻¹ and 2.30–6.00 ​t ​ha⁻¹ in the main and ratoon seasons, respectively. The grain quality in ratoon season is similar to or even better than that of late-season rice, but the relatively poor grain quality in the main season limits the profits for farmers. In recent years, research on the cultivation technology of ratoon rice has been widely conducted in Hunan, which led to the development of a series of key practices for ratoon rice production with regard to variety selection, sowing dates, crop establishment, fertilizer and water management, straw cutting height and harvesting time, and the controls of pests, diseases, and abiotic stresses. However, the constraints in policy intervention, as well as the large yield gap, have greatly limited the further expansion of ratoon rice in Hunan. To further promote ratoon rice production in Hunan, the innovation and extension of fully mechanized ratoon rice cultivation technologies, breeding and chemical regulation approaches to enhance ratooning ability, and support from the local government regarding policy, infrastructure, demonstration, and training must be strengthened in the future.