BIOASSAY OF ALLELOPATHIC POTENTIAL OF BERMUDAGRASS AND SORGHUM ON GERMINATION AND RELATED TRAITS OF WEEDS ASSOCIATED WITH RICE

Abstract

With growing concern towards human health and ecological concerns related to prolonged use of herbicides, research is undergoing globally for alternate weed managing methods. Allelopathy is one of the very efficient methods for management of weeds. Experiment was conducted during 2016 & repeated in 2017 under laboratory conditions in Kharif (summer) season using completely randomized design for allelopathic potential assessment of bermudagrass (Cynodon dactylon L.) and sorghum (Sorghum bicolor L.) with 03 replicates. The treatments under study comprised: control (check), bermudagrass & sorghum root & shoot powders @ 15 and 30 g kg^-1 soil as well as water extracts @ 15 and 30 ml kg^-1 soil. It is obvious from the present data that allelopathic plants powders & water extracts caused significant adverse effects on tested weeds i.e. Sawari (Echinochloa colonum L.), Saon (Echinochloaa crusgalli L.) and Kabah (Cyperus rotundus L.). Bermuda grass and sorghum water extracts exhibited strong allelopathic efficacy on germination, roots & shoots length, as well as fresh & dry biological weight of weeds included under study. It is further argued that greater inhibitory effects on weeds were caused by extracts prepared from bermudagrass and sorghum in comparison with their powders. Hence, it is evident from the results that bermudagrass & sorghum materials possess phytotoxic potential which can suppress growth of target plant. This allelopathic herbage could be utilized by soil incorporation or extract for weed management in rice as environment friendly strategy.