propagation coefficient meaning in English

传播常数
传播系数
繁殖系数

And development foregrounds is that propagation coefficient of the tip meristem culture is high and the range of increasing in yield is clear
茎尖组织培养前景广阔，具有繁殖系数高、增产幅度大等特点。
The results of quantitative analysis showed that the pre - tension deformation reduced the fatigue crack propagation threshold and increased the crack propagation coefficient , and consequently decreased the fatigue resistance of the part with mechanical damage
定量分析表明：预拉伸变形降低了疲劳裂纹扩展门槛值，提高了裂纹扩展系数，从而使管线在机械损伤的部位疲劳抗力降低。