*Contribution from the Department of Agronomy, Punjab Agricultural University, Ludhiana, 141 004, Punjab, India
Allelopathic effects of some important weeds on wheat (T. aestivum) have been studied. The fresh plant mass of Avena ludoviciana and Phalaris minor promoted the wheat seedling growth, while dry straw and glumes inhibited it. The other weeds which inhibited the growth of wheat seedlings were Cheaopodium album, Lepidium satlva, stem and root of Silene conoidea, Sonchus arvensis, Amarantbus viridis and Celosia argentea. Weeds which promoted the growth were Melilotus indica, leaves of S. conoidea and Rumex denta-tus. Cirsium arvense promoted the length of seedlings but reduced their dry weight.
