Allelopathic Assessment of Aqueous Extracts of Winter Weeds on Growth of Little Canary Grass (Phalaris minor Retz.) and Wheat (Triticum aestivum L.)

Medicago denticulata, Chenopodium album and Melilotus indica are the major annual weeds of cultivated wheat, other than Phalaris minor which is the most dominant one. In order to determine the allelopathic potential of these winter weeds, sole aqueous extracts of 10 % concentration and their combinations were tested on growth of wheat and Phalaris minor in a field experiment. Results showed that application of extracts showed non-significant effect on germination and plant height of wheat while seedling emergence of Phalaris minor was reported lower under treatments containing Melilotus indica aqueous extracts, however, plant height of Phalaris minor was found at par under different treatments at each crop growth stage (15, 30, 45, 60 DAS and at maturity). Medicago denticulata (10%) + Melilotus indica (10%) + Chenopodium album (10%) and Melilotus indica (10%) + Chenopodium album (10%) were the best treatments in terms of dry matter accumulation of wheat and led to lowest dry matter production in Phalaris minor. Inhibitory effect of weed aqueous extracts on growth and development of Phalaris minor however reduced with subsequent stages of crop growth, being 75% at 15 DAS and 25% by maturity stage. The treatments with Melilotus indica weed aqueous extracts recorded higher weed control efficiency than other treatments at each crop growth stage, statistically highest being under Medicago denticulata (10%) + Melilotus indica (10%) + Chenopodium album (10%). This study validated the allelopathic potential of all three weeds and concluded that combination of aqueous extracts of Medicago denticulata (10%), Melilotus indica (10%) and Chenopodium album (10%) and Melilotus indica (10%) + Chenopodium album (10%) achieved significant control of Phalaris minor and led to better growth of wheat as well.