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

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 30ppm as compared to control. The maximum increase in shoot yield was 48 % over control by the application of 10ppm Ni with vermicompost. The plant height and number of branches per plant were significantly increased by the application of 10ppm 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 (50ppm) 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.