Allelochemical Compound Study from Cyperus rotundus L. as Bioherbicide for Broadleaf Weed Control

Abstract

This research was conducted at Seed and Technology Laboratory of IPB, Cikabayan Greenhouse, Darmaga, Bogor and Regional Health Laboratory, Jakarta from July 2011 until May 2012 to study the potency of allelochemical compounds from Cyperus rotundus L. as bioherbicide for broadleaf weed control (Asystasia gangetica, Borreria alata and Mimosa pigra). The research consisted of 3 experiments. The objective of the first experiment was to study breaking treatment of seed dormancy for Asystasia gangetica, Mimosa pigra and Borreria alata. The weed treatment were soaked in 50 0C warm water for 24 hours, soaked in 90 0C hot water and embedded in soil for 4 days and control. The result showed that burrying Borreria alata seed in the soil for 4 days, soaking Mimosa pigra seed in hot water could be used as dormancy breaking treatments. No dormancy breaking treatment needed for Asystasia gangetica. The second experiment was conducted to study the influence of C. rotundus extracts on pre-emergence of broadleaf weed. The treatments used 0.5, until 4.5 kg/L with interval 0.5 kg/L concentration of extract (C. rotundus biomass with aquadest). The third experiment was conducted to determine the effect of C. rotundus extracts, mixed with fresh and dried C. rotundus biomass with soil, mulched of fresh and dried C. rotundus biomass, compost and flour of C. rotundus to weed growth and developmentand soybean. The experiment was using completely randomized design in observation of germination and randomized block design in weed growth. The result showed that 1.0 kg/L concentration of C. rotundus extract caused lower weed seed germination but have no effect on soybean germination. Applications of C. rotundus biomass have no effect on the growth and development of weed and soybean. Application of C. rotundus extract 1.0 kg/L potentially can be used as pre-emergence bioherbicide.