Study on Allelopathic Effect of Cocklebur (Xanthium indicum) on Macromolecular Contents of Green Gram (Phaseolus radiatus L.)

Abstract

Article InfoWeed releases an array of bioactive secondary metabolites from its various parts such as leaves, stem, root and sometimes decomposed body residues through different mechanism into its surrounding environment. The bioactive chemicals are often termed as allelochemicals and interact with plants which are present in vicinity. Effects of allelochemicals to the agricultural and biological ecosystem are may be positive or negative basing on the type of weed, crop plants and soil medium. Xanthium indicum L. and green gram are growing on paddy field after harvesting of the paddy. Green gram is cultivated by farmer on the post harvested paddy field during winter season in the mean time dormant seeds of the test weed are breakdown dormancy by cold treatment and germinated to produce plants along with crop. Hence, a pot experiment was conducted to find out the effect of various types of leachate of Xanthium indicum with its different graded dose (5, 10, 15 and 20 %) on total carbohydrate and protein content. The data of total carbohydrate and protein content obtained revealed a significant negative correlations with increase in the various types of leachate concentrations of test weed and positive correlations with increase in growth period upto 10 DAS thereafter a negative correlation were marked. This indicates that allelopathic stress of various types of leachates of Xanthium indicum L. were phytotoxic to green gram, when incubation period increase (i.e. 10 days after sowing) the degree of toxicity was higher, this might have due to profuse root system and absorbed more allelochemicals by plant as a result altering or blocking the process of intermediate biochemical pathways which reduced the macromolecular contents. The main purpose of this pot culture experiment is to highlight the adverse allelopathic effect of Xanthium indicum L. on green gram in agro-ecosystem.