Mung beans have high economic value and are in demand by the public, but there has been a decline in green bean production due to the presence of weeds around the plants. The aim of this research is to obtain the types of weeds and their concentrations which can reduce the growth and yield of mung bean plants.The research was conducted on the 3rd floor of the Laboratory of Ecology and Plant Production Management, Faculty of Agriculture, Sebelas Maret University, Surakarta in June-September 2023. The method used was a two-factor Completely Randomized Design (CRD). The first factor was extracts of various types of weeds (Imperata cylindrica (L.), Chromolaena odorata (L.), Cyperus rotundus) and the second factor was extract concentration (0, 25, 50, and 75%), each treatment was repeated 3 times. The variables observed were plant height, number of leaves, number of branches, root length, fresh weight of straw, dry weight of straw, number of pods per plant, number of seeds per pod, weight of 100 seeds and weight of seeds per plant. Data analysis used analysis of variance (Anova) at the 95% significance level, and if there were significant differences, it was continued with the Duncan’s Multiple Range Test (DMRT) at the 95% significance level and correlation test between variables. The result showed that siam weed extract treatment can reduce the number of seeds per pod, 100 seed weight and seed weight per plant. The nut-grass weed extract reduced the number of branches of mung bean plants. An extract concentration of 75% reduces the weight of 100 mung bean seeds. The concentration of weed extract does not interact with the type of weed and is not able to inhibit growth and reduce the yield of mung bean plants at the age of eight weeks.
