Allelopathic effects of Spondias pinnata (L.f.) Kurz leaf extracts

Ei Han Kyaw and Hisashi Kato-Noguch

Abstract: Spondias pinnata (L.f.) Kurz (Anacardiaceae), a deciduous tree, is cultivated in home gardens in tropical southern Asia. The fruits, leaves, and flowers of S. pinnata are edible and its various parts have been traditionally utilized in folk medicine. Although it possesses a diverse range of pharmacological properties and several bioactive substances from the plant have been well reported, the allelopathic effects of S. pinnata have not yet been documented. Hence, in this study, we aim to explore the allelopathy of S. pinnata for weed control. Extracts of S. pinnata inhibited the germination and seedling growth of Lepidium sativum L., Lactuca sativa L., Echinochloa crus-galli (L.) P. Beauv., and Lolium multiflorum Lam. Significant reductions in the germination and seedling growth were observed as the extract concentration increased. The concentrations needed for 50% inhibition (I50) values of the test plant roots and shoots were 2.2 – 6.3 and 4.3 – 30.6 mg D.W. equivalent extract/mL, respectively. The S. pinnata extracts were purified through different chromatography steps, and an inhibitory substance (SPL – 1) was isolated. These results indicate that the S. pinnata extracts had an allelopathic effect, which may be caused by SPL – 1. The SPL – 1 could be released into the soil under S. pinnata trees through the decomposition of fallen leaves and possibly acts as a plant growth inhibitory substance. Therefore, the allelopathy of S. pinnata is potentially useful for weed management in an eco-friendly way.

Keywords: Allelopathy; Inhibitory substance; Spondias pinnata; Weed control

Date published: 2022-12-09