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The effects of aqueous leachate of Nicotiana plumbaginifolia Viv. on germination, seedling growth, amylase activity, sugar and starch contents of germinated seeds of maize (Zea mays L. cv. Uttam) were examined. Effects of leachate on photosynthetic pigments, protein content, activities of nitrate reductase and some antioxidants were also studied. Higher concentration of aqueous leachate of N. plumbaginifolia reduced the germination rate (GR). However, final germination percentage remained almost unaffected. Lower concentration of leachate stimulated the amylase activity and resulted in higher sugar content and GR. The increasing concentrations of leachate inhibited the conversion of starch into sugars. Allelochemicals decreased the amount of chlorophyll a, chlorophyll b, carotenoids, protein and nitrate reductase activity (NRA). The leachate of lower concentrations stimulated the activity of peroxidase but slight decrease was recorded in higher concentration. Superoxide dismutase and catalase exhibited concentration dependent increase except in seedlings treated with 100% concentration of leachate. Impairment of various metabolic activities due to leachate resulted in decreased root and shoot length.

The sunflower (Helianthus annuus L. cv. PAC 36) seedlings were inoculated with plant growth promoting rhizobacteria (PGPR), viz. Azotobacter chroococcum (A+), Bacillus polymyxa (B+), separately and in combination of the two (AB+). Relative water content and seedling growth were maximum in AB+ seedlings under control. Water stress significantly decreased the RWC, growth and dry mass of non-inoculated seedlings. However, inoculated seedlings maintained higher growth even under water stress. Pigments and protein contents decreased under water stress, but higher amount of the same was observed in stressed AB+ seedlings. Enhanced activity of nitrate reductase was recorded in AB+ seedlings with maximum in control. Water stress significantly decreased the nitrate reductase activity. A significant increase in the activity of superoxide dismutase (SOD) in leaves was recorded under water stress except in B+ with maximum increase in non-inoculated seedlings. Catalase (CAT) activity decreased in stressed non-inoculated seedlings while increased in the leaves of A+ and AB+ seedlings. Almost similar trends were recorded for both leaves and cotyledons. PGPR improved the water status in stressed seedlings and thereby physiological and biochemical parameters and thus ameliorated the severe effects of water stress.

Withania somnifera is one of the important medicinal plant grown for its root. The present experiment was carried out to evaluate the most efficient bioinoculants as a seed treatment for the growth and yield of W. somnifera under pot conditions. The results revealed that N-fixer Bacillus sp. (AZHGF1) strain was most efficient microbe for promoting growth and yield of W.somnifera. In the tested arbuscular mycorrhizal (AM) fungi, we have demonstrated that Glomus intraradices (GI) was the potential AM fungus for the better growth and root yield of W. somnifera. The rhizospheric population of bioinoculants was maintained which may be useful for the next cropping season plants. This technology may be adopted in many seed borne crops which may be useful in safe and sound management of soil health.

Medicinal coleus (Coleus forskohlii) is an important medicinal crop which contains forskolin in their roots. Because of continuous collection of roots from the wild sources, this plant has been included in the list of endangered species. The crop has a great potential in future due to the expected increase in demand for forskolin which is widely used in glaucoma, cardiac problems, eczema, asthma, and hypertension and also used in the treatment of certain types of cancers. With the present annual production of about 100 tons from 700 ha in India, cultivation of C. forskohlii is picking up because of its economic potential. However, the crop has not become very popular among farmers because of its susceptibility to many diseases of which root- rot/wilt is the most important, causing serious losses affecting the tuber yield. The present review focuses on various diseases of important medicinal plant C. forskohlii and their management. [Medicinal Plants 2011; 3(1) : 1-7].

Nodal and shoot tip explants were collected from field grown mature plants of pointed gourd (T. dioica) for initiation of shoot cultures. The sterilized explants were aseptically inoculated on MS medium supplemented with various concentrations of BAP and kinetin alone and in combinations. Observations were made on 15 explants showing shoot initiation, average length of shoot and number of days taken by nodal/shoot segments to initiate the shoots. Medium containing BAP (1mg/ml) proved better for establishment of nodal explants. Out of 15, 12 explants established successfully on this medium. The growth of shoots was also found better than on other media tried. It took minimum time (5–6 days) to initiate the culture and the length of the shoot was ~ 1.5 cm with a survival of 80%. BAP at a concentration of 1mg/ml was found most suitable for shoot initiation from nodal explants of T. dioica in the present study.