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Due to environment and sustainability issues, this century has witnessed a global attention in green technology in the field of materials science through the development of composites. So, natural fiber reinforced composites have become important field of green composite. The main objective of this paper is to investigate the effect of sisal fiber reinforcement in epoxy composites with random orientation. Sisal fiber is abundant, low cost, degradable and good strength fiber. Sisal fiber is separated from sisal leaf using suitable techniques and those fibers surface are modified by chemical pre-treatment method (alkali treatment5%NaOH solution). Pre-treated fiber with constant length and volume is reinforced in epoxy matrix. Pure epoxy and sisal fiber reinforced epoxy composites are prepared by hand lay-up method. The prepared composites are tested as per ASTM standard. Tensile strength, compression strength and water absorption test are examined for the composite. The properties of the prepared composites are compared with pure epoxy. Experimental results show that the fiber reinforced composites showed enhanced mechanical properties compared with plain epoxy composites.

In insects, diet plays an important role in growth and development. Insects can vary their diet composition based on their physiological needs. In this study we tested the influence of diet composition involving varying concentrations of macronutrients and zinc on the immune-tolerance following parasite and pathogen exposure in Spodoptera litura larvae. We also tested the insecticidal potential of Mesorhabditis belari, Enterobacter hormaechei and its secondary metabolites on Spodoptera litura larvae. The results shows macronutrient composition does not directly affect the larval tolerance to nematode infection. However, Zinc supplemented diet improved the immune tolerance. While larvae exposed to bacterial infection performed better on carbohydrate rich diet. Secondary metabolites from bacteria produced an immune response in dose dependent mortality. The study shows that the larvae maintained on different diet composition show varied immune tolerance which is based on the type of infection.

Nowadays, the use of chemical insecticides has led to development of resistance in insects, and causing harmful effect to non-target organisms and environment. Plant-mediated biopesticides are an alternative source for the management of insect pests. Present study focuses on lethal and sublethal effects of Manihot esculenta on immune response and antioxidant enzyme activity of Spodoptera litura larvae. The result shows that high toxicity of petroleum benzene leaf extract in S. litura larvae with LC50 of 109.89 mg/mL. FT-IR analysis of leaf extracts shows the presence of alkane, alkyl halides, misc, amines, esters and carboxylic acid. GC-MS analysis of extracts contains 10 compounds, notable among them are 9, 12-Octadecadienoic acid (10.93) and Lupeol (11.35), 4, 4, 6A, 6B, 8A, 11, 14 B-Octamethyl- (37.41). In addition, several sublethal effects of the leaf extract were also observed. There was a significant increase in the total haemocyte count and differential haemocyte count in S. litura larvae. Phenoloxidase (PO) levels, detoxification enzymes such as CytP450, GST and catalase levels were significantly increased, whereas, SOD levels were lower than the non-treated S. litura larvae. Manihot esculenta leaf extracts is an alternative to chemical insecticides for the management of S. litura larvae and may be used for the management of other agricultural insect pests.