Chrysanthemum White Rust On Plants
Caused by Puccinia horiana, this fungal disease is highly host-specific, affecting only Chrysanthemums. This fungus prefers cool, wet weather, making it proliferate in late summer and fall. It first originated in China and Japan, and it spread worldwide due to it taking a while for plants to manifest symptoms. This is also known as “latent periods” and was the reason why infected plants that seemed healthy were transported from garden to garden across countries. It spreads by spore through the air and primarily affects the plant’s foliage. It grows within the leaf tissue, extracting nutrients from the cells. This is why heavy attacks can cause collapse and premature death. Other types of rust affect Chrysanthemums, but white rust is the most dangerous.
