Impression of elevated Co2 on the herbivory of tomato fruit borer Helicoverpa armigera (Hubner)
Kalpana Bisht, Sunil Verma and NN Singh
The present study was conducted to observe the influence of elevated CO2 concentrations i.e. 550 ppm, 700 ppm on host (Tomato, pLycopersicon esculentum) and its insect herbivore (Tomato Fruit Borer, H. armigera, Hubner) in relation to ambient CO2 i.e. 398 ppm concentration in open top chambers and laboratory conditions between September to December, 2015. Biochemical analysis was done for the tomato leaves raised under elevated CO2 conditions, which included nitrogen, carbon, C:N ratio and phenol content analysis using different methods. The results of biochemical analysis showed that nitrogen per cent was 2.80 per cent and 2.52per cent as compared with ambient condition 3.78 per cent, carbon content did not affected by elevated CO2 concentrations. The C:N ratio was observed in increasing trend with the elevated CO2 level i.e. 11.8, 12.8 and 13 per cent in ambient, 550 ppm and 700 ppm respectively. However, no change was observed in phenol content of the leaves. While growth performance on H. armigera showed larval weight and larval duration were in increasing trend i.e. 0.72g (700ppm) and 20.15 days (700ppm) respectively. Moreover, pupal weight and fecundity were found in decreasing trend i.e. 0.28g and 424 eggs/female/day respectively.