1Department of Agroromy, Punjab Agricultural University, Ludhiana-141004, Punjab (India)
2Department of Plant Breeding, Punjab Agricultural University, Ludhiana-141004, Punjab (India)
Abstract
Allelopathic influence of some tropical weeds was studied on the growth and development of wheat and mungbean, as also on nitrogenase activity and growth of Rhizobium culture. It was observed that a few weeds have promotory allelopathic effects and such effects are species specific. Chenopodium album had promotory effects on growth and development of wheat and mungbean and also on nitrogenase activity and Rhizobium culture. Celosia argentea, Rumex dentatus and Phalaris minor also promoted wheat growth and increased grain yield. R. dentatus increased mungbean growth and nitrogenase activity. Avena ludoviciana and Cirsium arvense though increased the growth, depressed the niirogenase activity. The promotion or inhibi-tion of Rhizobium growth depended on the concentration of the extracts in the medium.
