adventitious plant

例句：

1. 1. Many plants are adventitious, meaning they grow from spores rather than seeds.
   许多植物是无性系的，这意味着它们通过孢子生长，而不是种子。
2. 2. In a garden, adventitious plants often provide shade and shelter for other plants.
   在花园里，无性系植物经常为其他植物提供阴凉和庇护。
3. 3. The adventitious roots of the tree can help it survive in harsh environments.
   这种树的无性系根可以让它适应恶劣的环境。