Effect of Elevated Carbon Dioxide on Life Cycle of Root-Knot Nematode, Meloidogyne incognita in Tomato

Tomato plants of two varieties namely Pusa Ruby (susceptible) and SL-120 (resistant) were taken to study the effect of elevated carbon dioxide on lifecycle of root-knot nematode, Meloidogyne incognita. One half of the plants in each variety were exposed to elevated CO2 of 550 ppm and the other half were exposed to ambient CO2 of 385 ppm. Fifteen days after CO2 exposure the plants were inoculated with the second stage juveniles of root-knot nematode and the nematode life stages were monitored. The nematode penetration increased by 40.41% in Pusa Ruby and 42.74% in SL-120 at elevated CO2 level than the ambient on 3rd DAI. The totallifecycle duration decreased by 3.5 and 4 days in Pusa Ruby and SL-120 at elevated CO2 level. The Cumulative Degree Hour values proved that the CO2 have no any direct role in determining nematode total life duration. The fecundity of RKN decreased by 8.09% in Pusa Ruby 38.84% in SL-120 under increased CO2. The percentage of hatching of first generation eggs obtained after increased CO2 exposure doesn't show any change.