Dharani Dhar Patra

Effect of metal tolerant plant growth promoting bacteria on growth and metal accumulation in Zea mays plants grown in fly ash amended soil.

The present study was undertaken to examine the effect of the application of fly ash (FA) into Garden soil (GS), with and without inoculation of plant growth promoting bacteria (PGPB), on the growth and metal uptake by Zea mays plants. Three FA tolerant PGPB strains, Pseudomonas sp. PS5, PS14, and Bacillus sp. BC29 were isolated from FA contaminated soils and assessed for their plant growth promoting features on the Z. mays plants. All three strains were also examined for their ability to solubilize phosphate and to produce Indole Acetic Acid (IAA), siderophores, and hydrogencynide acid (HCN) production. Although inoculation of all strains significantly enhanced the growth of plants at both the concentration of FA but maximum growth was observed in plants inoculated with BC29 and PS14 at low level (25%) of FA concentration. The experimental results explored the plant growth promoting features of selected strains which not only enhanced growth and biomass of plants but also protected them from toxicity of FA.

Influence of Nickel and Cadmium Resistant PGPB on Metal Accumulation and Growth Responses of Lycopersicon esculentum Plants Grown in Fly Ash Amended Soil

Abstractpt?>Two cadmium- and nickel-resistant plant growth-promoting bacteria, Pseudomonas sp. ASSP 5 and ASSP 29, were isolated from fly ash-contaminated sites, and their plant growth promotion ability was tested by inoculating Lycopersicon esculentum plants grown in fly ash-amended soil. Parameters that were monitored included plant height, wet and dry weights, protein and chlorophyll content in leaves, and concentration of metals in plant root and shoot systems. Although both the bacterial isolates were effective, in most cases, ASSP 29 Pseudomonas sp. exerted a more pronounced effect on plant growth than did ASSP 5. The present observations also showed that both the strains ASSP 5 and ASSP 29 protect the plants against the inhibitory effect of nickel and cadmium, probably due to the production of indole acetic acid and siderophore, and solubilization of phosphate.

Utilization of Distillation Waste–Based Vermicompost and Other Organic and Inorganic Fertilizers on Improving Production Potential in Geranium and Soil Health

Vermicompost (VC) produced from distillation waste of geranium (Pelargonium graveolens), farmyard manure (FYM) produced from animal excreta mixed with pine needle (Pinus sp.), and biofertilzer (Azotobacter) were utilized for this experiment. The plant growth attributes, biomass, and oil yield of geranium were significantly increased with integrated nutrient supply, and maximum increase was found in T8 treatments (N100P60 K60 + 5t VC). Soil organic carbon (Corg) significantly increased by 4.2% to 81.8% in T4 and T8 treatments, respectively, over the control. Data obtained on total nitrogen (Nt) and available N, phosphorus (P), and potassium (K) clearly showed that the integrated nutrient supply considerably improved the soil health and sustainability. The soil respiration and microbial biomass C (Cmic) and N (Nmic) were increased by the manures according to the application rate. The Cmic accounted for 1.8 to 2.7% of the soil Corg content and microbial N accounted for 3.9 to 5.8 % of Nt under different treatment combinations.

Integrated Nutrient Management on Biomass, Oil Yields and Essential Oil Composition of Peppermint (Mentha piperita L.) and Residual Fertility in a Hilly Soil

Abstract A field experiment was conducted to study the influence of combined use of farm yard manure and inorganic fertilizers on biomass and essential oil yields, chemical and microbial biomass carbon and nitrogen of soil grown with peppermint (Mentha piperita) in a hilly region, Bageshwar, India. Combined application of both farm yard manure and inorganic fertilizers increased the biomass and oil yields of peppermint compared to sole inorganic fertilizers treatments. The treatments receiving both farm yard manure and inorganic fertilizers improved the soil organic carbon and total N from initial value of 3.9 to 7.0 g kg-1 soil and 0.27 to 0.58 g kg-1 soil, respectively. A significant improvement has been noticed in soil respiration, soil microbial biomass carbon and nitrogen compared to inorganic fertilizer alone. Moreover, different proportions of inorganic fertilizers with farm yard manure had significant variation on available major soil nutrients. A significant correlation coefficient (r= 0.41* to 0.98**) was observed between yields and soil properties. The quality of essential oil was good and acceptable for the market.

Effect of Nickel and Vermicompost on Growth, Yield, Accumulation of Heavy Metals and Essential Oil Quality of Tagetes minuta

Abstract The effect of nickel and vermicompost on growth yield and chemical composition of essential oil and mineral element accumulation of Tagetes minuta was studied in a pot experiment. The shoot yield of Tagetes minuta was significantly increased by the application of vermicompost and nickel up to 30 ppm as compared to control. The maximum increase in shoot yield was 48 % over control by the application of 10 ppm Ni with vermicompost. The plant height and number of branches per plant were significantly increased by the application of 10 ppm of Ni alone and in combination with vermicompost as compared to control and further increase in the level of Ni decrease the plant height and number of branches per plant. The level of dihydrotagetone and ocimene in Tagetes minuta oil were significantly decreased by the application of higher level of Ni (50 ppm) compared to control. The level of tagetone in T. minuta oil was decreased by the application of Ni alone and in combination with vermicompost as compared to control. The concentration of Ni in shoot and root tissues was significantly enhanced by the application of Ni and vermicompost. The concentration of Ni in leaf tissues of T. minuta was significantly higher than in the stem and root tissues. These results suggests that growing of T. minuta with vermicompost could be used as a green technology for rehabilitation and phytoremediation of Ni-contaminated soils.

Influence of different dates of planting on growth, herb, oil yield and quality of essential oil of menthol mint (Mentha arvensis) in the North Indian Plain

A field experiment was conducted for two years (2007–2008 and 2008–2009) to study the effect of different dates of planting for three menthol mint (Mentha arvensis) cultivars (Saksham, Kushal and Kosi; developed by Central Institute of Medicinal and Aromatic Plants, Lucknow, India) on herb yield, oil yield and oil quality. All the cultivars produced higher herb and oil yields when planted on 18 February, compared with cultivars planted on other dates in both years. Average herb yield for Saksham increased by 12.89, 30.66, 54.01 and 85.71%, average herb yield for Kushal increased by 15.09, 30.57, 71.69 and 104.91%, and average herb yield for Kosi increased by 32.48, 53.28, 87.23 and 109.49% when planted on 4 January, 19 January, 3 February and 18 February, respectively, over cultivars planted on 20 December. Among the cultivars, Kosi produced a higher herb yield than Saksham and Kushal planted on 18 February. Saksham, Kushal and Kosi produced ∼89.39, 152.04 and 170.22% higher oil yield, when planted on 18 February over their respective planting date of 20 December. Maximum menthol content was recorded in cultivar Saksham when planted on 18 February and in Kushal and Kosi when planted on 4 March.