Plant Secondary Metabolites in Alfalfa, Birdsfoot Trefoil, Reed Canarygrass, and Tall Fescue Unaffected by Two Different Nitrogen Sources

Abstract

Plant secondary metabolites (PSM) may increase the sustainability of agriculture systems by reducing inputs, as PSM protect plants against herbivores and pathogens, act as pesticides, insecticides, and anthelmintics while also attracting pollinators and seed dispersers. Therefore, it is important to understand what affects PSM fluctuation in plant tissues. Limited research has investigated how different nitrogen (N) sources affect PSM concentration in alfalfa (Medicago sativa L., Alf), birdsfoot trefoil (Lotus corniculatus L., BFT), reed canarygrass (Phalaris arundinacea L., RCG), and endophyte‐infected tall fescue (Festuca arundinacea Schreb., E+TF). We investigated how fecal manure (feces) and synthetic N fertilizer (urea, 46% H2NCONH2) influence N concentrations and the PSM ergovaline, gramine, saponins, and extractable condensed tannins (CT) in E+TF, RCG, Alf, and BFT, respectively. Ergovaline, saponins, and CT were not affected by fertilization. Gramine tended (P = 0.06) to be greater in control plots than in fertilized plots. Total N in E+TF and RCG was greater (P < 0.05) and tended to be greater for Alf (P = 0.08) in synthetically fertilized plots than in unfertilized plots. Seasonal variation in PSM and N was significant (P < 0.003) across all species and was species specific. Total N in E+TF was greatest in June (41.4 g kg−1), while ergovaline contents were at the lowest values recorded (117.2 μg kg−1), with subsequent increases to the greatest ergovaline values observed in July (680.0 μg kg−1). Our results reveal the variability in PSM production by plants and highlight the complexities of predicting fluctuations of PSM in forages. As environments where plants grow vary through space and time, we recommend studies on a case‐by‐case basis, depending on land management objectives.

Secondary metabolites from endophytic fungus from Lippia sidoides Cham.

“…The detection of three types of flavonoids, catechin, naringin, and quercetin, in the L. sidoides plant ( Figure 2B) also allows presenting and confirm the possibility of harnessing its leaves for biological applications. Several studies have already demonstrated the potential and ability of these metabolites to act to reduce the risks associated with pathologies such as intestinal inflammation, bacterial infections, diabetes, cardiovascular diseases, and cancer, among others (Clemensen et al, 2017;Macheleidt et al, 2016). In the present study, however, antifungal activities of the extracts are related to the antioxidative activity of flavonoids present in considerable amounts (Funari et al, 2012).…”

How planting configuration influences plant secondary metabolites and total N in tall fescue (Festuca arundinacea Schreb.), alfalfa (Medicago sativa L.) and birdsfoot trefoil (Lotus corniculatus L.): Implications for grazing management

“…Alfalfa samples were analysed as described by Clemensen et al. () with a modification of Lee, Stegelmeier, and Gardner () using the methods developed by Patamalai, Hejtmancik, Bridges, Hill, and Camp () and Wall, Eddy, McClennan, and Klumpp ().…”

Relative importance of drought, soil quality, and plant species in determining the strength of plant–herbivore interactions

“…But it is also possible that the different plant species respond differentially to the substrate by changes in the nutrient content or production of the secondary metabolites (e.g. Hagele & Rowell-Rahier, 1999;Clemensen et al, 2017). Such data are not available from our experiment.…”