近三年来,三交杂交稻在我省大面积种植,表现出制种高产、杂种抗逆性增强和增产的效果;种植面积正在逐年扩大。据省农业厅的统计,一九八一年全省三交稻的面积,已由一九七九年的20万亩左右,发展到83万亩以上。农作物杂种优势的一个普遍现象是杂种一代优势最强,而杂种二代性状会分离,优势要明显减弱。例如玉米的自交系杂种二代要比它的杂种一代减产二、三成以上;三交、双交玉 Over the past three years, three cross hybrid rice planted in large areas in our province, showing high seed production, increased hybrid resistance and stimulation effect; planting area is expanding year by year. According to the statistics of the Provincial Department of Agriculture, the area of ​​three cross-fertilized rice in the province in 1981 has grown from about 200,000 mu in 1979 to more than 83 million mu. A common phenomenon of crop heterosis is that the hybrid generation has the strongest advantage, while the hybrid second generation trait separates, and the advantage is obviously weakened. For example, hybrids of maize inbred hybrid II than its hybrid generation cut two or three percent above; three cross, double cross jade