Studies on leaf spot disease of Withania somnifera and its impact on secondary metabolites

Abstract

During an investigation of the disease profi le of Withania somnifera, it was observed that leaf spot is the most prevalent disease. Repeated isolations from infected leaf tissues and pathogenicity tests showed the association of fungal pathogen identifi ed as Alternaria alternata (Fr.) Keissler. Scanning electron microscopy showed various histological changes in the leaf tissues of infected plants. A decrease in total content of reducing sugars (20%) and chlorophyll (26.5%) was observed in diseased leaves whereas an increase was noticed in proline (25%), free amino acids (3%) and proteins (74.3%). High performance thin layer chromatography (HPTLC) analysis of secondary metabolites viz. withanolides, withaferin-A and total alkaloids of the diseased leaves vis-à-vis control revealed reduction in withaferin-A and withanolides contents by 15.4% and 76.3% respectively, in contrast to an increase in total alkaloids by 49.3%, information hitherto unreported in W. somnifera.

Optimizing factors affecting adventitious shoot regeneration, in vitro flowering and fruiting of Withania somnifera (L.) Dunal

“…It has been used in traditional medicine for the treatment of Alzheimer's disease, arthritis, cardiovascular disease, cold, dementia, dropsy, fever, female disorders, and hiccups (Kirtikar and Basu, 1975). Phytochemical studies revealed that W. somnifera contains a number of active constituents such as alkaloids, flavonoids and steroidal lactones (Pati et al, 2008;Mirjalili et al, 2009). In recent years, the demand for this plant species has sharply risen due to its biological activities.…”

Carbon-Mercaptooctadecane/Carboxylated Multi-walled Carbon Nanotubes Composite Based Genosensor for Detection of Bacterial Meningitis

“…5c) [27] which was changed into a dense surface morphology after hybridization with ssG-DNA of N. meningitidis from patient CSF (Fig. 5d) [28].…”

Withania somnifera (Ashwagandha): A wonder herb with multiple medicinal properties

“…But the crop is mainly attacked by fungal pathogens under field conditions, although deterioration of these crops due to other diseases has also been reported. Leaf spot is the most prevalent disease of W. somnifera Alternaria alternata caused by a fungus (Pati et al, 2008). The plant has also been reported to be affected by many other foliar diseases.…”