Intensive agriculture is spectacularly successful since last couple of decades due to the inputs viz; fertilizers and pesticides along with high yielding varieties.

Surfactants form a variety of microstructures in solution, some of which are equilibrium and the others are non-equilibrium microstructures. During the dissolution of a surfactant in a solvent, various types of non-equilibrium microstructures have been observed. The most interesting and fascinating non-equilibrium microstructure is the 'Myelin Figure'. In the present report the swelling and dissolution dynamics of the myelin growth in the surfactants Aerosol-OT (AOT) and phosphatidylcholine (PC) in aqueous medium have been studied. The effect of the additive para-toluene sulfonic acid (PTS) on the dynamics and the shape of these myelin structures have been investigated. The observation of coiling transformations in the presence of these additives has been studied. It is shown that the molecular diffusion of the surfactant from the interface and the flexibility of the interface are the two important parameters for formation, growth and coiling of myelin structures. Chemical reactions in myelins have been carried out to throw light on the water transport during the myelin growth.

A laboratory experiment was performed to study the persistence of imidacloprid from two formulations (Confidor 200 g litre-1 SL and Gaucho 700 g kg-1 WS), and its metabolism in three different soils (Gangetic alluvial soil of Kalyani, lateritic soil of Jhargram and coastal alkaline soil of Canning) of West Bengal following application at 0.5 kg and 1.0 kg AIha-1. Dissipation of imidacloprid in soil followed first-order kinetics and DT50 values ranged from 28.7 to 47.8 days. The shortest half-lives (28.7 and 35.8 days) were observed in the lateritic soil of Jhargram for both liquid and powder formulations. The formation of two metabolites of imidacloprid, imidacloprid-urea and imidacloprid-olefin, was first detected on day 30 of degradation at 28 (+/- 1) degrees C in all three soils.

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