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Background: Selenium (Se) is an essential micronutrient for humans, but its deficiency as well as toxicity affects large number of people worldwide. Plantago ovata, a commercially important medicinal plant, is mainly cultivated in western regions of India, where elevated levels of Se have been found in soil. Thus, we evaluated the potential of Se biofortification in P. ovata via phytoremediation and its effect on the bioactive composition. Results: The results showed a significant alteration in various morphological and physiological parameters in a dose-dependent manner. The 10 µM Se dose improved seedling height, biomass and total chlorophyll content. There was a gradual increase in total Se content, with highest accumulation of 457.65 µg/g FW at 500 µM Se treatment. Se positively affected the antioxidative metabolism which was measured from the change in total antioxidant capacity, radical scavenging activity and Metallothionein 2 expression. Increasing levels of Se also affected the PAL activity, total polyphenol and flavonoid content. Caffeic acid, Coumaric acid and Rutin were found to be the most abundant phenolic compounds. Conclusions: Low levels of selenium (below 50 µM) can successfully improve Se accumulation and elicit production of various polyphenols without hampering plant growth. Thus, Se fortification of P. ovata seedlings via phytoremediation appears to be a feasible and efficient way to enhance its nutraceutical value in dietary products. [ABSTRACT FROM AUTHOR]

There is growing global demand for medicinal drugs including isabgol (Plantago ovata). With increasing demand of food for an ever-increasing population in India, it is not possible to bring arable lands under cultivation for aromatic and medicinal plants. Salt-affected lands (both saline and alkali) occupy about 8∙6 million ha. Due to poor physical properties and excessive exchangeable Na+, most of these lands do not support good vegetation cover. The marginal and salt-affected lands could be successfully utilized for the cultivation of aromatic and medicinal plants. We achieved almost complete germination of isabgol seeds using up to 5000 ppm salt-solution. Grain yield (including husk) was 1∙47 to 1∙58 t ha-¹ at pH 9∙2 showing no significant yield reduction as compared to normal soil. At pH 9∙6 the grain yield was 1∙03 to 1∙12 t ha-¹. At higher pH there was significant reduction in yield. Sowing in good moisture (at field capacity) of soil was found best, but to save time sowing at shallow depth in dry soil, followed by irrigation was also suitable as compared to broadcasting seeds. The chlorophyll content was greater 70 days after sowing compared to younger stages (50 days after sowing). The total chlorophyll and plant biomass were lower from crops grown by broadcasting methods of sowing as compared to two other methods of sowing. The leaf area index (LAI) was higher for the broadcasting method of sowing as compared to the other two methods. Na+ absorption increased and K+ and K+/Na+ ratio decreased with increase in pH. Results reported in this paper clearly indicate that isabgol can successfully be grown on moderately alkali soils up to pH 96 without the application of any amendment. [ABSTRACT FROM AUTHOR]

During the winter season of 1996-1997, little leaf disease of psyllium (Plantago ovata) appeared for the first time in the experimental fields of CIMAP at Lucknow. Disease incidence ranged from 15 to 20 percent in severely infected fields with infected plants showing chlorosis, stunted growth, tiny leaves, excessive branching, and reduction in inflorescences. Electron microscopic studies revealed that infected leaf tissues contain numerous pleomorphic bodies that varied considerably in size (80-750 nm), shape (spherical, oval, some with budding) and electron opacity, and that were bounded by a smooth trilaminar membrane and contained ribosomes-like granules and DNA-like strands. Disease symptoms in infected plants showed remission if treated with tetracycline-HCL. The pathogen, not observed in healthy plants, appears to be a new type of phytoplasma. [ABSTRACT FROM PUBLISHER]