Symptoms associated with bacteria include leaf spots, soft rots, scabs, wilts, and galls. Fungal Pathogens Fungal pathogens can grow on living or dead host plants. Many fungi are able to penetrate host tissue using enzymes. Fungi grow wherever environmental conditions are favorable. Fungi reproduce by producing spores that can be either sexual or asexual in nature.
Many fungi require high humidity or free water for germination of spores.
Many fungal spores are able to survive long periods of unfavorable conditions and will germinate once conditions become favorable. Wind, splashed water, tools, machinery, and insects are ways in which fungal pathogens can come into contact with host plants. Symptoms associated with fungal pathogens include soft rots, stunting, curling of leaves, leafspots, wilts, mildews, and blights. General differences between diseases caused by fungal and bacterial pathogens are outlined below. Nov. 1982 Viruses Viral pathogens are minute organisms that cannot be seen unless highly magnified.