Allelopathic Influence of Leachates of Sesame Varieties on Germination and Growth of Weeds

Background: Allelopathy is described as the interference to plant growth resulting from chemical interactions among plants and other organisms mediated through release of plant-produced bioactive secondary metabolites referred to as allelochemicals. Harnessing the allelopathic properties of field crops offers a natural means of weed control without the need for external weed control agents in the field. The naturally occurring allelochemicals could be manipulated as a viable tool to control weeds and witness environment friendly and sustainable agricultural system (Farooq et al., 2020). Among the oilseed crops, sesame is an allelopathic crop, which can inhibit or stimulate other crops and suppress weeds. However, studies on the allelopathic effect of different sesame varieties are scanty. Methods: The experiment was conducted at College of Agriculture, Vellayani, Kerala, during June to September 2023 to examine the allelopathic effect of leachates prepared from different sesame varieties on germination and growth of three common weeds of Kerala viz., Alternanthera sessilis, Setaria barbata and Cyperus rotundus. The experiment was designed using CRD, with six treatments and pure water as control. Result: The allelopathic potential of sesame varied among the different tested varieties. All varieties showed inhibitory effect on germination and growth of the tested weeds. The leachates of varieties, GT-10 and TMV-5 showed the highest inhibitory effect on germination and growth attributes of all the three weeds. The germination percentage of Alternanthera sessilis, Setaria barbata and Cyperus rotundus were decreased by 83.33%, 86.67% and 90% respectively with the application of leachate of variety GT-10 compared to control. The seedling vigour index I (SVI I) and seedling vigour index II (SVI II) of Alternanthera sessilis, Setaria barbata and Cyperus rotundus treated with leachate of GT 10 were lower than control by 92.5% and 90.83% , 93.89% and 93.59% and 95.79 % and 96.73% respectively compared to control. The inhibitory effect of sesame leachates could be considered as an eco-friendly approach in weed management.