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Acid soil is a hindrance to agricultural productivity and a threat to food and environmental security. Research was carried out to assess the impact of lime and organic manure (OM) amendments on yield and nutrient uptake by using the T. Aman-Maize-Fallow cropping pattern in acid soils. The experiment was set up in an RCBD design and used nine treatments and three replications. The treatments, comprising of various doses of lime, OM (cow dung and poultry manure), and a lime-OM combination, were applied to the first crop, T. Aman (Binadhan 7), and in the next crop, maize (BARI Hybrid Maize-9), the residual impacts of the treatments were assessed. Results demonstrate that the highest grain yield, 4.84 t ha−1 (13.61% increase over control) was recorded for T. Aman and 8.38 t ha−1 (58.71% increase over control) for maize, was achieved when dololime was applied in combination with poultry manure. The total rice equivalent yield increase over the control ranged from 20.5% to 66.1%. The application of lime with cow dung or poultry manure considerably enhanced N, P, K, and S content and uptake in both crops, compared to the control. Thus, it may be inferred that using dololime in association with poultry manure can increase crop productivity in acid soils.

A novel sensing platform for the study of enzymatic kinetics using gold nanoparticles dispersed in a film of fourth generation PAMAM-OS-trimethoxysilyl dendrimer self assembled on indium tin oxide (ITO) electrodes is proposed. An overlayer of chitosan formed on the gold nanoparticles modified ITO electrode is used for the immobilization of an enzyme namely, horseradish peroxidase. In addition to a single layer of gold nanoparticles, multilayer assembly method is also studied. The strategy used for the modification resulted in a new third generation amperometric biosensor for hydrogen peroxide (H2O2). Different steps corresponding to the modification strategy employed in this work are characterized using microscopic (SEM & AFM) and electrochemical techniques. The resulting biosensor exhibited excellent sensing toward H2O2 in neutral phosphate buffer. Influence of gold nanoparticles in increasing the loading of active enzyme molecules and the amplification of catalytic activity are observed. The lowest detection limit is determined to be 0.165 mM with a sensitivity of 0.3151 μA/mM (for 3-layers) and 0.07614 μA/mM (for a single layer) as determined from the cyclic voltammetric data. The apparent Michaelis – Menten rate constant is calculated to be 0.119 mM. The enzyme turn-over is estimated to be 4.873 s−1. This biosensor provides a wide response range toward H2O2 detection with an excellent reproducibility.