High temperature stress at heading stage is one of the important natural disasters causing the reduction of the seed setting rate of rice in the middle-lower reaches of Yangtze River. This study investigated the effects of high temperature stress at heading stage on fertilization rate of modern rice varieties and combinations, including modern inbred japonica, three-line hybrid indica rice and two-line hybrid indica rice cultivars under the field condition. The modern inbred japonica cultivar showed better ...