A disease caused by a plant pathogen that invades a plant's vascular tissue and spreads throughout all parts of the plant is a ...

A disease caused by a plant pathogen that invades a plant's vascular tissue and spreads throughout all parts of the plant is a ...

• A. Systemic Disease
• B. Localized Disease
• C. Fungal Disease
• D. Viral Disease

Answer: (A)

A systemic disease is one where the pathogen invades the plant’s vascular tissue and moves through the plant, reaching multiple parts. When the pathogen travels via the xylem or phloem, it isn’t confined to a single leaf or one spot—the infection can spread to roots, stems, and shoots, causing symptoms across the plant. Localized diseases stay at the initial infection site and don’t spread through the vascular system, so they don’t produce the widespread impact described here. The fact that the pathogen travels through the plant’s transport system, rather than remaining in one location, is what defines a systemic infection. Although fungi, bacteria, and viruses can all cause systemic infections, the key idea is the pattern of movement through vascular tissues leading to widespread symptoms like overall decline, wilting, or discoloration throughout the plant.

A systemic disease is one where the pathogen invades the plant’s vascular tissue and moves through the plant, reaching multiple parts. When the pathogen travels via the xylem or phloem, it isn’t confined to a single leaf or one spot—the infection can spread to roots, stems, and shoots, causing symptoms across the plant. Localized diseases stay at the initial infection site and don’t spread through the vascular system, so they don’t produce the widespread impact described here. The fact that the pathogen travels through the plant’s transport system, rather than remaining in one location, is what defines a systemic infection. Although fungi, bacteria, and viruses can all cause systemic infections, the key idea is the pattern of movement through vascular tissues leading to widespread symptoms like overall decline, wilting, or discoloration throughout the plant.