Allelopathic Activity of Leaf and Root Extracts of Clidemia hirta to Morpho-Physiological Characters of Rice (Oryza sativa) and Some Weeds of Rice Field

The decline in worldwide rice production could be attributed to weed infestations. Weeds hinder the growth of rice plants, leading to reduced rice production. Conversely, the study and potency of extract of Clidemia hirta D.Don as bioherbicide in rice is limited. Based on these characteristics, Cl. hirta is suspected to have allelopathic potential as an herbicide to enhance rice production by inhibiting weed growth. Therefore, this research aimed to analyze the extract of the invasive alien species (IAS) plant Cl. hirta as an allelopathic agent in inhibiting weed growth in rice cultivation. The research methods include the identification and inventory of plant seeds, the preparation of leaf and root extracts of Cl. hirta in a water-based solvent, allelopathy extract tests on rice and weeds in the seedling and vegetative growth stages, morphological character analysis as a physiological response to the extract, and phytochemical tests. The tested weed species include Ageratum conyzoides, Echinochloa crus-galli, Cyperus iria and Ludwigia octovalvis, while the rice variety used is IR64 as a control. In summary, both leaf and root extracts of Cl. hirta inhibit the growth of A. conyzoides, E. crusgalli, Cy. iria and L. octovalvis. In contrast, rice growth was actually stimulated by the extract. Therefore, this study is expected to serve as a reference for the development of bioherbicides for rice cv. IR64.