Weed Extract of Ageratum conyzoides and Chromolaena odorata to Suppress Weed Growth in the Edamame Cultivation

Abstract

Allelochemicals are alternatives for reducing chemical herbicide applications. These are plant-based compounds with phytogrowth-inhibitory activities. Allelochemicals can be found in several plant species, including Ageratum conyzoides (Ac) and Chromolaena odorata (Co). This study aimed to investigate the effects of aqueous crude extract of A. conyzoides and C. odorata, known as weed extracts, at various concentrations to suppress weeds in edamame cultivation. The experiment was conducted at the experimental field in Cangapan, Jetis, Bantul, Indonesia and carried out during the period of July to October 2022. This study employed Randomized Complete Block Design (RCBD) model, which consisted of 9 treatments and 3 repetitions, i.e., Ac 15%, Ac 30%, Co 15%, Co 30%, Ac 7.5% + Co 7.5%, Ac 7.5% + Co 15%, Ac 15% + Co 7.5%, Ac 15% + Co 15%, and control. The collected data were analyzed using Analysis of Variance and Tukey's test at the 5% level. This study has shown that weed extract suppresses weed growth with the best application at Ac 15% + Co 15%, with 43.63% efficiency. Weed extract application also shows slight injuries on edamame leaves. However, there is no decreased in chlorophyll content due to the tolerance ability of edamame to allelochemicals.