Allelopathic interaction of wheat (Triticum aestivum) and littleseed canarygrass (Phalaris minor)

Allelopathy is a plant-plant or plant-microbe interaction in which one plant produces secondary metabolites i.e., allelochemicals, which may influence the chemistry of its rhizosphere and affect the growth of neighbouring plants. Management of weeds using synthetic chemicals is environmentally hazardous. Allelopathy is cost effective and eco-friendly natural phenomenon that can be manipulated for weed management. An experiment was conducted to study the allelopathic interaction of wheat and littleseed canarygrass using the equal-compartment-agar method. Wheat cultivars and promising lines (Faisalabad-08, Lasani-08, Shafaq-06, Sehar-06, Miraj-08, Farid-06, Chakwal-50, V-04178, V-05066 and V-05082) were used to study their allelopathic interaction with littleseed canarygrass. Each wheat cultivar was grown alone and in association with littleseed canarygrass in glass beakers containing water agar solution, kept in a growth cabinet maintaining 25/18°C day and night temperature, respectively; 13/11 h light/dark period. Littleseed canarygrass was also grown alone as control for comparisons. Results revealed that wheat cultivars had differential allelopathic inhibition activity against littleseed canarygrass through the production of phenolic compounds. Maximum inhibition in root length (54%), shoot length (59%), root dry weight (60%) and shoot dry weight (55%) of littleseed canarygrass was recorded when grown in association with wheat cv. Shafaq-06, while all these growth parameters were less in association with cv. Sehar-06. Significant increase in production of total soluble phenolics was also observed in root and shoot of all wheat cultivars when grown in association with littleseed canarygrass as compared to when grown alone. In conclusion, cv. Shafaq-06 was found strongly allelopathic against littleseed canarygrass.