Allelochemicals of invasive tree species Senna spectabilis alleviate antioxidant enzymes activities in native plants of the Western Ghats

Abstract

Abstract Invasive alien species are major threats to biodiversity worldwide. Senna spectabilis is one such species that has been introduced to several countries, including India. This study aimed to investigate the allelopathic potential of S. spectabilis and its effects on seedlings of native plants over a period of three years. Assays such as metabolic activity, L-proline estimation, lipid peroxidation, antioxidant enzyme assay, and polyphenol oxidase activity were used to assess the allelopathic potential of S. spectabilis and finally, bioactive phytochemical components were identified by Gas chromatography coupled with mass spectrometry (GC–MS). The metabolic activity of treated seedlings decreased significantly, while lipid peroxidation and L-proline content increased. Antioxidant enzyme activities were also increased in response to S. spectabilis extract. GC-MS analysis detected 28 phytoconstituents in the leaf extracts prepared from 5 different solvents, and 7 plant allelochemicals were identified. The results showed that S. spectabilis extracts contained several allelochemicals, including phenolic compounds, fatty acids, and terpenoids. These findings suggest that S. spectabilis has strong allelopathic potential, which could contribute to its invasive potential. The present study highlights the need for effective management strategies to control the spread of this invasive species and the importance of selecting specific native species for restoration programme.