水稻是我国最重要的粮食作物,种植面积约占粮食作物总面积的30%,总产却占粮食总产的40%。稻米是我国50%以上人口的主食。在我国人口年增加约1500万,耕地不断减少的形势下,要保证粮食自给就必须大力提高水稻单产。在提高水稻单产的诸措施中,选育和推广良种最为经济有效。我国在20世纪50年代后期利用矮秆基因率先育成高产抗倒品种,形成了第一次“绿色革命”;70年代初,又在世界上首次将杂交 Rice is the most important grain crop in our country. The planting area accounts for about 30% of the total area of ​​the food crops, while the total output accounts for 40% of the total grain output. Rice is the staple food of more than 50% of China’s population. Under the situation of an annual increase of about 15 million in our population and ever-decreasing cultivated land, we must vigorously raise the yield of rice to ensure self-sufficiency of grain. Among the measures to increase rice yields, the most cost-effective breeding and promotion of improved varieties is. In the late 1950s, China used the dwarf gene to breed high-yielding varieties and formed the first “green revolution”. In the early 1970s, it was the first hybridization in the world