自然变异 meaning in English

natural variation
sporadic mutation

" there may have been something about that particular season in terms of either natural variation in susceptibility patterns going on but also then potentially this low - level community transmission of variants with reduced susceptibility as well , ' ' he said
他说： “也许是在特殊的季节，病毒的敏感谱发生了自然变异，或者敏感性降低的变异病毒株在社区内低水平地传播。 ”
And they have not been studied taxonomically . as an attempt to study the taxonomy in cultivated species level of magnoliaceae , 20 various species were tested for rapd analysis . based on the rapd analysis and some morphological characters , the materials of yulania were divided into five groups : yulania , liliflore , biondii , sprengeri , and soulangeana group
2 、依据rapd聚类分析结果和形态学特征，将玉兰亚属的种、自然变异类型和栽培品种进行了类群划分，将20个供试材料分为白玉兰类群、紫玉兰类群、望春玉兰类群、武当木兰类群和二乔玉兰类群。