Increase in growth, productivity and nutritional status of wheat (Triticum aestivum L. cv. WH-711) and enrichment in soil fertility applied with organic matrix entrapped urea.

Field experiments were conducted during two consequent years in semi-arid, subtropical climate of Rohtak district situated in North-West Indian state Haryana to evaluate the effects of eco-friendly organic matrix entrapped urea (OMEU) on wheat (Triticum aestivum L. cv. WH-711). The OMEU prepared in granular form contained cow dung, rice bran (grain cover of Oryza sativa), neem (Azadirachta indica) leaves and clay soil (diameter of particles <0.002mm) in 1:1:1:1 ratios and saresh (plant gum of Acacia sp.) as binder entrapping half of the recommended dose of urea. A basal application of organic matrix entrapped urea showed increase in plant growth in terms of fresh and dry weights, root length, root number, leaf number, tillers, plant height, earlet number, earlet length and productivity in terms of grain yield and straw yield over free form of urea (FU) and no fertilizer (NF) application. The OMEU increased total soluble proteins, organic N and free ammonium content in the leaves at 45 and 60 days. The nutritional status of wheat grains in OMEU applied plants was almost similar to that observed for FU applied plants. An increase in organic carbon and available phosphorus (P) was observed in OMEU applied plots on harvest, whereas pH was slightly decreased over FU applied plots. The microbial population and activity in terms of fungal and bacterial colony count and activities soil dehydrogenase and alkaline phosphatase were significantly higher in OMEU applied plots as compared to the FU applied plots. Our data indicate that OMEU which are low cost, biodegradable and non-toxic can be used to replace the expensive chemical fertilizers for wheat cultivation in semi-arid, subtropical climate.

Genotypic variation in Brassica juncea (L.) Czern. cultivars in growth, nitrate assimilation, antioxidant responses and phytoremediation potential during cadmium stress.

Four cultivars of Brassica juncea i.e. TM-4, TM-2, RH-30 and T-59 were screened for seed germination and seedling growth up to 15 days in the presence of 0.5-1.5 mM cadmium (Cd). The exposure to Cd reduced seed germination and seedling growth (root and shoot length and dry weight) in all four cultivars; the effect being more severe in TM-2 and RH-30 than in TM-4 and T-59 and at 3 d than at 7 d and 15 d. The cultivars TM-4 and T-59, with higher tolerance to Cd toxicity, were selected for further analysis including the estimation of nitrate reductase (NR) and peroxidase (POD) activities, total organic nitrogen (TON), total soluble proteins, proline levels and Cd accumulation. The NR activity and total soluble proteins decreased upon Cd exposure in a concentration dependent manner, whereas TON increased significantly in 3 d seedlings upon Cd exposure. The activity of POD and proline level increased significantly as compared to the respective controls. The level of Cd accumulation was higher in T-59 than in TM-4. Therefore, T-59 was found to be the most tolerant cultivar to Cd than other three cultivars possibly due to a better capacity to transport Cd in their vacuolar sink. The variety T-59, thus, appears to be suitable for Cd phytoremediation.