From the Field-Agronomy Notes
Tobacco Research Update: Nitrogen Deficiency of Tobacco
In this tobacco research update, we highlight the symptoms of nitrogen deficiency. These images are part of a project supported by the North Carolina Tobacco Foundation to develop a web-based diagnostic key for the identification of nutrient disorders of tobacco.
By far, nitrogen (N) is the most widely applied nutrient for plant growth. It should come as no surprise, that symptoms of nitrogen deficiency are readily induced in plants.
In tobacco, one of the first indicators of limited N is slowed growth (Fig. 1). Plant growth stalls and leaf expansion does not occur. Visual symptoms of N deficiency quickly follow. When N supplies are limited, the plant will reallocate N from the lower leaves to the upper leaves, due to the fact that N is a mobile element. This is the reason why symptoms initially develop on the lower foliage.
The initial symptom of N deficiency is a paler green coloration of the lower leaves (Fig. 2). The progression to more advanced symptoms readily occurs when N is unavailable to the plant. Pale green leaves will begin to change to a light yellow, that becomes progressively more bleached over time (Fig. 3). These symptoms may be observed in the attached continuously rotating image (Fig. 4, click image to play video). Ultimately, these bleach-yellow leaves will turn brown (senesce) and fall off the plant.
We would like to express our appreciation to the North Carolina Tobacco Foundation for supporting this project. We will be providing updates as symptoms progress over the course of the nutrient disorder induction phase of the experiment.
Key Contact: Dr. Matthew Vann, Department of Crop and Soil Science firstname.lastname@example.org
Contributing Authors: Josh Henry, Paul Cockson, Matthew Vann, and Brian Whipker
Funding Source: North Carolina Tobacco Foundation
Project Team: Josh Henry (NC State M.S. student in Horticultural Science), Paul Cockson (NC State B.S. student in Agroecology), Ingram McCall (Research Technician in Horticultural Science), Rhonda Conlon (Extension IT at NC State), Matthew Vann (Tobacco Extension Specialist, Dept. of Crop and Soil Science), and Brian Whipker (Professor of Floriculture and Plant Nutrition in Horticultural Science).