Recent data showed that global climate change negatively impacted maize production in the world. These negative impacts of climate on maize yield can be attributed to water stress and increasing atmospheric temperature. Water stress reduces maize yield by negatively impacting photosynthesis. This is mainly due to the reduced water availability at reproductive stages and decreased leaf expansion under water stress. The central objective was to get an idea on the effects of CO2 enrichment during the vegetative growth stages of maize under water stress. Maize seeds were water soaked for 24 hours before seeding and were seeded in to 72 well plastic trays in a growth chambers. We maintained two such growth chambers: ambient (430 ppm) and enriched (800-1100 ppm) CO2 treatments. Three different water stress treatments were assessed: One irrigation to field capacity per 7 days (SD); One irrigation to field capacity per 14 days (FD) and One irrigation to field capacity per 21 days (TD). Maize leaves were harvested to determine chlorophyll content, stomatal density, stomatal size, and epidermal cell size.
Results/Conclusions
In enriched CO2 environment, FD and TD drought treatments showed significantly higher chlorophyll `a' and chlorophyll `b' contents from SD drought treatments. Stomatal length and width showed irregular responses to the combined CO2 enrichment and water stress treatments. Stomatal length showed the trend TD<SD<FD. Stomatal density showed irregular numbers in different water stress treatments under ambient and enriched CO2 environments. The widths of epidermal cells showed an irregular trend in case of SD and TD, while FD showed highest averages. Not all eco-physiological parameters in corn were significantly affected by CO2 enrichment. But longer drought treatments (FD and TD) resulted in higher chlorophyll content in corn.