Teline monspessulana Can Harm the Chilean Native Tree Nothofagus obliqua: Effects on Germination and Initial Growth

Abstract

Teline monspessulana is highly invasive in several countries around the world. This species pressurizes and displaces several native and endemic tree species in south-central Chile such as Nothofagus obliqua, the native species of greatest timber interest. We determined the effects induced by allelochemical stress of T. monspessulana on N. obliqua germination and initial growth. Germination was evaluated under in vitro conditions and in natural substrate obtained from sites inhabited by N. obliqua and from nearby areas invaded by T. monspessulana. Controls irrigated with tap water and treatments with aqueous extracts of aerial organs of the invasive species were used. Morphometric and morphological variables were evaluated, and the composition of alkaloids and phenols from the plant organs used for the aqueous extracts was determined. The substrates were also chemically characterized. Allelochemicals synthesized by T. monspessulana caused germination and growth inhibition and tissue-level alterations, as well as leaf and root damage in N. obliqua seedlings. In the aerial organs of T. monspessulana, the quinolizidine alkaloids aphylline, caulophylline, anagyrine, and sophocarpine were mainly detected. In addition, 21 phenolic compounds were identified, including gallic acid, vanillic acid, chlorogenic acid, p-coumaric acid, and quercetin. The phytotoxic potential of T. monspessulana can compromise the natural multiplication of N. obliqua and its survival from its first phenological stages. This interdisciplinary study model facilitated the clarification of the plant–plant relationship mediated by allelochemicals. The model can be replicated to investigate other interspecific interactions between invasive and native species.

Phenolic Antioxidant Protection in the Initial Growth of Cryptocarya alba: Two Different Responses against Two Invasive Fabaceae

“…Although the allelopathic potential of T. monspessulana has been little investigated, a recent study showed the presence of at least seven alkaloids and 21 phenols in T. monspessulana aerial organs, which were related to the allelopathic effect exerted on the native Chilean species Nothofagus obliqua (Mirb.) Oerst [28]. Similarly, some previous studies have demonstrated the allelopathic potential of U. europaeus [29][30][31].…”

“…It is well documented that allelopathic stress can also affect the structure and activity of the root apical meristem, which affects water and nutrient absorption, implying a delay in root growth [39][40][41], as has also been observed in C. alba seedlings under UE stress. Prior works show the allelopathic capacity of T. monspessulana and U. europaeus over the early growth of N. obliqua [28] and Quillaja saponaria Molina [42], two Chilean native species. The allelopathic effect of U. europaeus on the growth and development of agricultural species [30], Lactuca sativa L. [31],…”

“…For example, the presence of alkaloids N-methylcytisine, lupanine, argentamine, thermopsine, N-[2-aminoethyl] cytisine, and cytisine in the methanol extract of U. europaeus has been tied to cytotoxic effects [31]. The alkaloids caulophylline, lupanine, aphylline, anagyrine, sophocarpine, ellipticine, and cytisine have also been detected in T. monspessulana [28]. Allelopathic compounds are released into the environment through leaching, volatilization, root exudation, and organ decomposition [6].…”