Spatial variation in allelopathic inhibition by Ageratina adenophora on growth and yield of two traditional millet crops

摘要

Abstract This study investigated the effects of Ageratina adenophora Sprengel (King and Robinson) on the growth and grain yield of two millet crops viz. finger millet (Eleusine coracana) along with the red and white variety of barnyard millet (Echinochloa frumentacea). Plants of selected millet crops growing at three distances (0, 1 and 5 m) from A. adenophora were harvested at mature stage and analysed for plant height, dry mass and grain yield. Significant inhibitory effects were recorded on all measured variables including shoot and root length and dry mass, panicle size and grain yield. In general, red barnyard millet was found to be more sensitive to allelopathic effects of A. adenophora as compared to white barnyard and finger millet. Distance from A. adenophora strongly affected the allelopathic effects; generally decreasing with increasing distance. Grain yield was the most inhibited variable for both the barnyard varieties, and reductions of 72 and 83 were observed in white and red barnyard millet, respectively. While finger millet showed maximum inhibition in plant biomass (18). Harvest index showed maximum inhibition (57) in red barnyard followed by white barnyard (15) millet while finger millet remained unaffected. This study concluded that both finger and barnyard millet are sensitive to A. adenophora invasion and observed growth reductions in finger and barnyard millet may be due to the allelochemicals present in the A. adenophora plants.