In this experiment studied were the major factors influencing
ryegrass yield in a ryegrass rice
rotation system, including
the way of planting, the quantity of seed used and the type and quantity of fertilizer applied. It was shown that a high amount of seed use ( 22.5% kg/ha), sown by direct spreading into the paddy field one month before the rice being harvested, would bring about a good yield (9 183.45 kg/ha of dry matter and 1 668 kg/ha of crude protein) of quality
ryegrass fodder as an aftercrop. As the above method is labour saving and can utilise the soil moisture in the paddy field efficiently during the fallowing period, it is recommended as a major way to utilise paddy fields for fodder production during the winter time. As an option, a relatively labour intensive, but seed saving and early harvesting method is also introduced. With this latter method, 15 kg/ha of seed are needed and a yield of 9 765.45 kg/ha of dry matter and 1 730.25 kg/ha of crude protein can be obtained. For both the methods the rate of 1 500 kg/ha of fertilizer mix (N∶P 2O 5∶K 2O=15∶15∶15) is recommended as the optimum.