Image Number: 5368915

Photographer:
Descriptor:
Symptoms
Description:
The spots usually start as small dark green water-soaked areas. Within 48 hours, the lesions change to a brown color then to a gray or white and appear as sunken necrotic areas bordered by chlorotic tissue (on dark tobacco you usually do not see any yellow halo). The spots are often concentrated along the side of the midrib and large secondary veins but can be found anywhere on the leaf. On expanding leaves the spots appear near the tip. Lower leaf surfaces may show no evidence of damage in the early stages. Lesions may run together causing the leaf surface to become necrotic and fall out. Symptoms may occur at any growth stage, but most commonly occur during periods of rapid growth. Older leaves are more susceptible. Dark fired types usually show less injury than burley types when at the same growth stage and exposed to the same level of ozone.
Image type:
Laboratory

You must attribute the work in the manner specified (but not in any way that suggests endorsement). You may not use this work for commercial purposes unless permission is granted by the photographer or copyright owner.

Image location:
Kentucky, United States

Subject

Kingdom: Other damage agents
Phylum: Other damage agents
Class: Other damage agents
Order: Abiotic
Family: Other abiotic damage
Subject: weather fleck

Host

Kingdom: Plantae
Phylum: Magnoliophyta
Class: Magnoliopsida
Subclass: Asteridae
Order: Solanales
Family: Solanaceae
Genus: Nicotiana
Subject: Nicotiana tabacum (dark type) L.
Node Affiliation:
Image uploaded:
Thursday, March 6, 2008
Image last updated:
Wednesday, November 12, 2008