Effects of NO 2 on Inflorescence Length, Pollen/Seed Amount and Phenolic Metabolites of Common Ragweed ( Ambrosia artemisiifolia L.)

Abstract

Ambrosia artemisiifolia L. (common ragweed) is an annual ruderal plant that is native to Northern America but nowadays is also spreading across Europe, and its pollen is known to be highly allergenic. Air pollution, e.g. NOx and climate change may affect the plant growth, pollen production and duration of the entire pollen season. In this study, ragweed plants were grown over an entire vegetation period under 40 ppb NO2/clean air (control) and 80 ppb NO2 (treatment). The inflorescence length was not affected by this air pollutant. However, the pollen amount increased, while the seed production decreased in both populations upon elevated NO2 concentrations. Regarding phenolic metabolites elevated NO2 had no effect on the amount of total phenolic metabolites, while individual metabolites showed significant changes.