The prevalence of Senna tora in Peninsular Malaysia Azimah Abd. Kadir, Nor A. Ismail, Nurin I. M. Zulkifli, Farah F. Haron, Michael D. Day, Quentin Paynter, Che A. A. Che Omar, Maizatul A. Yahya

Abstract

Senna tora, an important medicinal plant in Malaysia, is a major introduced pasture weed in the Pacific island nation of Vanuatu. This weed contains toxic compounds, including sennosides, which can be harmful to livestock if ingested in large quantities. The seeds spread easily, leading to infestations in pastures and rangelands. A biological control program to mitigate its impacts in Vanuatu commenced, with funding from the New Zealand government. Early literature searches and climate matching suggested that Southeast Asia was the most promising region to survey for natural enemies. Therefore, surveys were conducted to determine the distribution of S. tora in Malaysia, which will help identify the best places to search for potential candidates for biological control. Field studies were conducted within a 30-60 km radius of the first location chosen based on accessible roads and near water resources. The distribution of S. tora in Malaysia occurred mostly along the west coast of Peninsular Malaysia. The highest density of S. tora was observed in Johor, followed by Negeri Sembilan and Pahang. Perlis had the lowest density, while other states fell in between. This weed is most abundant in abandoned areas, shrubland, and near rivers.