Article citationsMore>>
Punja, Z.K., Wan, A., Lieppi, L., Goswami, R.S. and Jayaraj, J. (2013) Growth, Pathogenicity, Infection Behaviour, and Genetic Diversity of Rhexocercosporidium Isolates Originating From Ginseng Fields in British Columbia. Canadian Journal of Plant Pathology, 35, 503-513.
http://dx.doi.org/10.1080/07060661.2013.843315
has been cited by the following article:
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TITLE:
Morphological and Biochemical Changes in Ginseng Seedling Roots Affected with Stripe Symptoms
AUTHORS:
Zamir K. Punja, Mahfuzur Rahman
KEYWORDS:
Cell Disruption, Iron Sequestration, Panax quinquefolius, Phenolics, Root Epidermis
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.6 No.16,
October
19,
2015
ABSTRACT: A unique symptom of longitudinal red stripes on the surface of one-year-old ginseng roots was
studied to determine the morphological and biochemical changes taking place. Light and scanning
electron microscopy, measurements of phenolic and mineral element content, and enzyme activity,
were compared between healthy and stripe-affected root tissues. Light microscopy revealed that
the root epidermis had ruptured and fissures extended for 3 - 4 cell layers into the cortex. Phenolic
compounds accumulated in the epidermal cells which stained with Toluidine blue 0. Total phenolic
content was higher in tissues from striped roots compared to healthy roots and HPLC profiles
showed increases in a number of specific phenolic compounds. Analysis of epidermal tissues
by SEM-EDX for mineral element content showed a marked increase in levels of iron, silicon and
aluminum and a decline in potassium in striped root tissues. The activity of the enzymes phenylalanine
ammonia lyase and peroxidase were also found to be higher in striped root tissues. Striping
of ginseng roots is a physiological condition caused by a rupture of the epidermis due to rapid
growth of underlying cells, which results in phenolic accumulation and sequestration of several
minerals. Further oxidation causes a visible red striping on the root surface.