He noted that a dish in which he was trying to grow bacteria for an experiment looked abnormal - there was blue mould in it.
他注意到，他想为实验培养细菌的培养皿看起来不正常--上面有蓝色的霉菌。
英语百科
Blue mold
（重定向自Blue mould）
Blue mold is a downy mildew disease of tobacco that is caused by Peronospora tabacina, a fungus-like protist in the family Peronosporaceae. Blue mold can cause severe damage to susceptible tobacco plants in many parts of the world. Since it is an obligate parasite, it must have living tobacco tissue in order to grow.