Abstract:

In view of the lack of suitable varieties for ratooning rice production in eastern Hubei, the evaluation index of ratooning ability is not clear, and the identification methods are not unified，the study aims to screen suitable ratoon rice varieties in eastern Hubei and establish an evaluation system for ratooning ability. A field trial was conducted in Huanggang City in 2023 using 23 hybrid rice varieties as materials. The growth duration, agronomic traits and yield were analyzed, and key indicators for evaluating ratooning ability were identified through regression analysis. The growth period of the tested varieties ranged from 184 to 213 days, with the regeneration bud emergence rate showing the greatest variation (8.5%-85.6%, CV=43%) and significantly correlated with yield (R²=0.902). Based on ratoon season yields (1350 to 4500 kg/hm²), ratooning ability was classified into four grades. Among the indicators, the regeneration bud emergence rate on the 7^th day after harvest of the main crop, the number of effective panicles in the ratoon season, and the tiller number per seedling at the maximum seedling stage achieved classification accuracy rates of 68.75%, 70.25% and 47.38%, respectively, allowing them to serve as core screening indicators. 16 varieties, such as ‘Jingchuyou 89’, ‘E Liangyou 88’, were identified as suitable varieties for cultivation. Among them, 4 varieties, including ‘E Liangyou 88’, ‘Xinxiang Liangyou 3927’, Yuxiangyou 8133 and ‘Sheng Liangyou 311’, achieved total annual yields exceeding 13,000 kg/hm², demonstrating outstanding yield performance. This study identified core indicators for evaluating ratooning ability and screened multiple suitable varieties, providing a scientific basis for selection and production of ratoon rice in eastern Hubei.

Key words: eastern Hubei, ratoon rice, variety screening, ratooning ability, evaluation