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Background: Biologically active compounds derived from the many of medicinal plants have become an important source for developing natural products to act as an antioxidant, insecticidal, antimicrobial and antifungal properties. So the current work was aimed to determine the bioactive components present in the leaves of Erythrina variegata by using GC-MS analysis to assess the antioxidant, insecticidal, antimicrobial and antifungal properties. Methods: The laboratory experiment was carried out at the Department of Seed Science and Technology, Tamil Nadu Agricultural University, Coimbatore during 2019-2020 to ascertain the phytochemical extraction using different solvents, viz., water, ethanol and hexane by GC-MS analysis of the leaves of Erythrina variegata. Result: GC-MS analysis of aqueous, ethanol and hexane leaf extracts revealed the presence of twenty four, twenty six and twenty two components, respectively. Of the twenty four compounds eluted from the aqueous leaf extract, 9,12-Octadecadienoic acid (Z,Z)-, 2-hydroxy-1-(hydroxymethyl)ethyl ester had the highest peak area of 11.98%, while the lowest was 0.33 % for oleic acid,eicosyl ester and 1,2,3-butanetriol. In the ethanol leaf extract diethyl phthalate had the highest peak area of 35.04% and d-streptamine, O-6-amino-6-deoxy-à-D-glucopyranosyl-(1-4)-O- (3-deoxy-4-C-methyl-3- (methylamino) -á-L-arabinopyranosyl- (1-6) -2-deoxy-with the lowest peak area of 0.40%. Whereas, phenol,2,6-bis (1,1-dimethyl ethyl)- and dasycarpidan-1-methanol, acetate (ester) had the the lowest peak area of 0.20% and 9-octadecenoic acid (Z)-, 2,3-dihydroxypropyl ester exhibited the highest peak area of 13.41%, respectively, in the hexane leaf extract. The results of the present study clearly indicated that the leaf extract of Erythrina variegata possesses potent antioxidant, antibacterial, antifungal, antimicrobial, pesticide, insecticide, insect repellent, larvicidal activity, antibiotic, free radical scavenger, peroxidase substrate, reductant, lipid peroxidase inhibitor, plasticizer, surfactant and emulsifying properties. [ABSTRACT FROM AUTHOR]

The field experiment was carried out in the orchard, Horticultural College and Research Institute, TNAU, Coimbatore from September 2016 to April 2017 to monitor the seasonal abundance of insect pests by installing colored sticky traps. The experiment result showed that the maximum number of A. gosypii was trapped on yellow sticky traps with the meantrap catches of 50.68 A. gosypii per trap per week followed by 9.75 A. gosypii in blue sticky traps as against the minimum number of 1.70 A. gosypii in a red sticky trap. The maximum number of A. dispersus was trapped on yellow sticky traps with the mean trap catches of 34.82 per trap per week followed by 10.46 in blue sticky traps as against the minimum number of 1.68 spiraling whiteflies in a red sticky trap. The maximum number of B. tabaci was trapped on yellow sticky traps with the meantrap catches of 14.83 per trap per week followed by 6.01 in blue sticky traps as against the minimum number of 0.73 whiteflies in a red sticky trap. [ABSTRACT FROM AUTHOR]

A field experiment was conducted in the farmer's holdings at Kalathupudhur village, Coimbatore district in Tamil Nadu during 2015-2016. Experimental results revealed that the maximum number of PDI were recorded in untreated control 86.86 per cent followed by famer's practise 52 per cent, as minimum number of PDI were recorded in IPM plot 14.20 per cent at 121 DAS. Regarding fruit yield parameters, maximum numbers of harvestable fruits were recorded in IPM plot (11.85), followed by farmer's practice (8.28) as against lowest number of 4.71 fruits per plant in untreated control. The maximum fruit yield of 34.12 tonnes per ha was recorded in IPM plot followed by farmer's practise 22.53 tonnes per ha, as against the minimum fruit yield and cost benefit ratio of 8.62 tonnes per ha in untreated control, respectively. Based on the experimental results revealed that the IPM strategy was significantly superior to farmer's practice and untreated control in reducing the per cent disease incidence, number of fruits per plant and fruits yield. [ABSTRACT FROM AUTHOR]