CO2 Fertilizer Effect on Growth, Polyphenols, and Endophytes in Two Baccharis Species

Abstract

In a climate change context, the buildup of CO2 will affect plant communities worldwide. This study evaluated the effects of CO2 enrichment on the development and defense of two Cerrado native species Baccharis dracunculifolia and B. platypoda and their associated endophytic fungi richness. The study took place in Open-Top Chambers, two with ambient CO2 concentration (~400 ppm) and two in an enriched environment (~800 ppm). Baccharis platypoda developed 20% more leaves under enriched CO2 conditions, whereas B. dracunculifolia was 30% taller and showed 27% more leaves than those under ambient conditions. In both species, leaf polyphenol concentration did not differ between treatments. Nevertheless, polyphenol content had a positive correlation with plant height on both species' individuals grown under CO2 enriched conditions. Endophytic fungi richness and colonization rate on both plant species did not differ between ambient and enriched conditions. Our results show the positive effect of CO2 fertilizer in at least one of the measured growth parameters. An important new finding was a synergistic increase in growth and chemical defense in both studied species under enriched CO2 conditions, suggesting higher carbon assimilation and accumulation. This study suggests that the effects on primary productivity and secondary metabolites of Baccharis species will potentially reflect on the diversity and distribution of Cerrado plants and their associated animal communities.

Elevated CO2 concentration improves the performance of an agricultural pest: a worrisome climate crisis scenario

“…Flavonoids are biosynthesized via the phenylpropanoid (PAL) pathway, which demands high levels of carbohydrates to operate. Therefore, if Flv content increased, it is reasonable to infer that other allelochemicals may have increased as well (O'Neill et al, 2010;Oki et al, 2020) and further hampered early instar performance (Zavala et al, 2013;Prasifka et al, 2015).…”

“…According to Hall et al (2020), eCO 2 could also cause alterations in plant resource allocation and hormone production (e.g., jasmonic and salicylic acid). These changes may increase the production of secondary metabolites with allelochemical functions (Zavala et al, 2013;Oki et al, 2020), such as flavonoids (Flv) and sesquiterpenoids, commonly found in Asteraceae species (Prasifka et al, 2015).…”

The Influence of Elevated CO2 on Volatile Emissions, Photosynthetic Characteristics, and Pigment Content in Brassicaceae Plants Species and Varieties

“…Carbon dioxide fertilization has not affected the total phenols determined in chickpea leaves [ 18 ]. Leaf polyphenol concentrations found in two Cerrado native species, Baccharis dracunculifolia and B. platypoda , grown at 400 ppmv and 800 ppmv carbon dioxide, have not been statistically significant [ 19 ].…”