Metabolite analysis of the effects of elevated CO₂ and nitrogen fertilization on the association between tall fescue (Schedonorus arundinaceus) and its fungal symbiont Neotyphodium coenophialum

Abstract

Atmospheric CO2 is expected to increase to between 550 ppm and 1000 ppm in the next century. CO2-induced changes in plant physiology can have ecosystem-wide implications and may alter plant-plant, plant-herbivore and plant-symbiont interactions. We examined the effects of three concentrations of CO2 (390, 800 and 1000 ppm) and two concentrations of nitrogen fertilizer (0.004 g N/week versus 0.2 g N/week) on the physiological response of Neotyphodium fungal endophyte-infected and uninfected tall fescue plants. We used quantitative PCR to estimate the concentration of endophyte under altered CO2 and N conditions. We found that elevated CO2 increased the concentration of water-soluble carbohydrates and decreased the concentration of plant total amino acids in plants. Fungal-derived alkaloids decreased in response to elevated CO2 and increased in response to nitrogen fertilization. Endophyte concentration (expressed as the number of copies of an endophyte-specific gene per total genomic DNA) increased under elevated CO2 and nitrogen fertilization. The correlation between endophyte concentration and alkaloid production observed at ambient conditions was not observed under elevated CO2. These results suggest that nutrient exchange dynamics important for maintaining the symbiotic relationship between fungal endophytes and their grass hosts may be altered by changes in environmental variables such as CO2 and nitrogen fertilization.

Co2 Effects on Larval Development and Genetics of Mealworm Beetle, Tenebrio Molitor L. (Coleoptera: Tenebrionidae) in Two Different Co2 Systems

“…Based on previous research, the fitness level of M. persicae was decreased when feeding on the pepper plants grown under higher CO 2 concentrations. Similar results were recorded on species of Brassicaceae (Oehme et al, 2011) such as Brevicoryne brassicae on Brussels sprout (Ryan et al, 2014), and Acyrthosiphon pisum on the broad bean (Ryan et al, 2014). Other than that, elevated CO 2 also affects their morphology and physiology by reducing fertility and producing a fewer number of offspring, as well as increasing chewing insects development duration (Dáder et al, 2016).…”

New insights into carbon acquisition and exchanges within the coral–dinoflagellate symbiosis under NH 4 + and NO 3 − supply

“…Nutrient-induced changes in host-symbiont interactions have been well studied in terrestrial plant-fungal associations [68], but much less is known about it in aquatic systems. There are still large gaps in our understanding on how nutrients affect marine symbioses.…”

Advances in understanding CO2 responsive plant metabolomes in the era of climate change

“…Regallo), elevated CO 2 (700 ppm) caused an increase in the accumulation of carbohydrates, and a decrease in AAs and total nitrogen (N) in leaves (Aranjuelo et al 2011). Similarly, in tall fescue (Schedonorus arundinaceus) treated with elevated and high CO 2 showed that both treatments increased the concentration of water-soluble carbohydrates compared to ambient controls (Ryan et al 2014). It is interesting to note that in the two aforementioned studies, decreases in AAs and total N-content were observed, thus indicating increases in C/N ratio due to elevated CO 2 .…”