1、Fungi are an example of ectogenous organisms that grow externally on plants.
真菌是生长在植物外部的外源生物的一个例子。

2、The insect infestation on the crops is believed to be caused by ectogenous factors such as climate conditions and environmental changes.
作物上的昆虫侵扰被认为是由于气候条件和环境变化等外来因素引起的。