Natural products derived from plants are emerging as potent biorational alternatives to synthetic insecticides for the integrated management of post harvest insects of maize. In this paper, effectiveness of botanicals including plant extracts, essential oils, their isolated pure compounds, plant based nano formulations and their mode of action against storage insects have been reviewed with special reference to maize. Plant based insecticides found to be the most promising means of controlling storage insects of maize in an eco friendly and sustainable manner. This article also throws light on the commercialization of botanicals, their limitations, challenges and future trends of storage insect management.

A novel polymer nanocomposite has been synthesized in the present study using a bio-polymer Karaya and inorganic SiO2 nanoparticles via sonication for application as a fracturing fluid in stimulating oil and gas wells. Gum Karaya (KG), an acidic polysaccharide, has been investigated for its structural, morphological and rheological characteristics, and the results have been compared with prepared KG–SiO2 nanocomposite at different SiO2 dosing for improved structure, viscoelasticity, viscosity and temperature stability. Steady shear rheology test depicted pseudoplastic nature, while oscillatory study confirms gel characteristics and weak dependence of storage and loss moduli on frequency for all the prepared samples. Dominance of elasticity over viscous nature of the gel assures efficient solid transporting/suspending capability. Experimental results showed that the rheological characteristics of the synthesized gel is comparable with Guar and CMHPG over the shear and temperature ranges under study and suitable for temperatures above 150 °C and pressure conditions. Also, polymer breaking and sandpack regained permeability tests proved synthesized gels to be a cleaner with less residue as compared to the other two.

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The time for gravity draining of water from a large Cylindrical open tank by means of a drain pipe ( Located at the center of the bottom of the storage tank) is measured experimentally for the case of turbulent flow conditions in the drain pipe. Further, to reduce draining time, experiments are also conducted by the addition of water soluble Carboxymethyl Cellulose (CMC). The concentrations of CMC considered are 0.625,1.25, 2.5 and 5ppm respectively. The optimum concentration of CMC is found to be 0.625 ppm. Further, the re-usability of CMC polymer solutions is also contemplated and it is noted that there is an increase in draining time upon re-use of the CMC polymer solutions.