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Background: Agricultural chemicals, metals, industrial effluents, plastics, excessive dumping of unused and expired pharmaceutical chemicals etc. contaminate terrestrial, aquatic and aerial environment. The excessive usage of the unwanted chemicals elicits undesirable effects in the non target organism inhabited in the various environments. The soil biota like earthworm faces threats of the environmental contaminants. A number of research works has been carried out to study the impact of certain environmental pollutants on the terrestrial inhabitant like earthworms which are widely utilized in the waste disposal management. Tamarind shell waste is considered one of the unwanted materials dumped in the road side and being discharged from industry and from the houses. The bio waste is now a day’s utilized for various purposes. The environmental contaminants such as diclofenac and bisphenol-A are discharged into the environment and finally reach the terrestrial environment where the inhabitants are adversely affected. Hence the study has been focused to analyze the efficiency of earthworm Eudrilus eugeniae in the conversion of tamarind shell waste mixed separately with Diclofenac and bisphenol-A. Methods: Vermibed was prepared for the present work. The vermibed contains cow dung and garden soil which are common in all the pots. One pot was considered as control. The second pot was mixed with tamarind shell waste. The third pot was mixed with diclofenac and finally in the last pot bisphenol-A was taken. Healthy earworms were selected and released to the four pots. The experimental set up was maintained for 30 days. Correlation matrix and t-test was performed to understand the significance of the results.Result: The study revealed the impact of pollutants on the bioconversion of tamarind shell waste. The contaminants like diclofenac and bisphenol-A significantly decreased the micro and macro nutrient levels. The phosphorous, nitrogen and potassium level showed a decrease when compared to control on 30th day in the diclofenac treatment. The nitrogen value was also decreased in the bisphenol-A treated compost on 30th day and the value was statistically significant. The other nutrients, phosphorous and iron were also decreased significantly (P less than 0.05) in the treatment and correlation matrix showed positive and negative correlation with micro and macro nutrients. The physico-chemical characters such as pH and electrical conductivity are also altered in the experimental conditions.

A field investigation was carried out during Rabi season (Pishanam rice) of 2012-2013 at wetland of Central Farm, Agricultural College and Research Institute, TNAU, Killikulam, to study the effect of integrated nutrient management practices on dry matter production, yield and NPK uptake of transplanted rice. The treatments were laid out in a Randomized Block Design and replicated thrice using the rice variety ADT(R) 45. Among the different integrated nutrient management practices, application of GLM @ 6.25 t ha-1 + Azophosmet + 100 % NPK registered significantly the highest (P<0.01) dry matter production at all the stages (Active tillering; 1690, flowering; 9100 and harvest;14490 kg ha-1). The grain yield was increased, when GLM was integrated with 100 % NPK application (6030 kg ha-1). The grain yield was further increased, when Azophosmet was applied through seed and soil application along with GLM and 100 % NPK (6617 kg ha-1). However, it was on par with application of FYM + Azophosmet + 100 % NPK. The same trend was noticed in straw yield also. The uptake of N, P and K nutrients by rice crop at har-vest stages (95.6, 37.7 and 118 kg ha-1) of crop growth was remarkably increased by the application of GLM + Azophosmet + 100 % NPK. Among the various nutrient management practices, application of GLM + Azophosmet + 100 % NPK registered superior growth indicators due to the effective utilization of various nutrients and subsequent accumulation of more assimilates which inturn led to improved vegetative growth and higher yield of transplanted rice.

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