any disease or disorder. regardless of their.. causal agent that kills young plant tissues .
Merriam-Webster Online Dictionary
blight (noun)1.
a) a disease or injury of plants marked by the formation of lesions, withering, and death of parts (as leaves and tubers)
b) an organism (as an insect or a fungus) that causes blight
2.
something that frustrates plans or hopes
3.
something that impairs or destroys
4.
a deteriorated condition - urban blight
transitive verb
1.
to affect (as a plant) with blight
2.
intransitive verb
to impair the quality or effect of - the condition that has blighted his son's life Patricia Guthrie to suffer from or become affected with blight
blight (Wikipedia)
Blight refers to a specific sign affecting plants in response to infection by a pathogenic organism.