Investigation on the forage utilization of indica and japonica weedy rice with strong ratooning ability

Abstract There was few research on the utilization and development of weedy rice. Some weedy rice has remarkable good characteristics as forage in some soil which is difficult to plant crops and pastures. In this study, two weedy rice lines of japonica and indica subspecies with high ratooning ability (Xijing, japonica ; Gaoxian, indica ) were used to study the possibility of their forage utilization and related suitable cultivation methods. Three different stubble heights of first season were set in 2018 and 2019, and three cutting times of first season (heading stage, milk stage, and waxy ripening stage) were set in 2019. The ratoon grass was harvested 40 days after the first season harvest. For japonica weedy rice line Xijing, its grass yield was significantly lower than that of indica weedy rice line Gaoxian. The dry matter yield of first season grass plus ratoon grass of Gaoxian with the first season harvested at milk stage was the highest of all. The total digestible dry matter yield (first season grass plus ratoon grass) of Gaoxian with 15 cm cutting stubble of first season was higher than those of stubble 30 and 45 cm treatments ( p < .05). In conclusions, indica weedy rice line Gaoxian, with high biomass of first season and good ratooning ability, had the good potential for forage development by harvesting first season at milk stage with 15 cm stubble height.