What is a girdle in plant anatomy?

A girdle in plant anatomy refers to a complete circle of dead tissue that forms around the stem of a plant. This interruption of the vascular system, specifically the phloem and cambium, disrupts the flow of nutrients and water, effectively severing the food supply pipeline between the roots and the leaves. This condition can be caused by various factors, including mechanical injuries, insect damage, or environmental stress.

When a girdle occurs, the affected plant section above the girdle may suffer from starvation, leading to wilting, stunted growth, and eventual dieback if the girdle circulates completely around the stem. Consequently, understanding the implications of girdling is crucial for diagnosing plant health issues and effectively managing plant care.

In contrast, other choices involve different aspects of plant structure and function that do not pertain to the definition of a girdle. For instance, the areas where leaves grow from the stem relate to node development, underground root structures refer to specialized root anatomy, and the main support structure for a plant describes the role of stems or trunks, neither of which captures the precise definition or impact of a girdle.