Effect Of Weed Residues On The Physiology Of Common Cereal Crops

The allelopathic influence of plant residues of three dominant weeds of NorthWestern Himalayan region, namely, Eupatorium adenophorum, Ageratum conyzoides and Lantana camara was observed on the germination and early growth of three common cereal crops viz., Triticum aestivum cv. HPW-42, Oryza sativa cv. Hasanshrai Basmati and Zea mays cv. Girija. The effect of soil amended with weed residues at two concentrations (5 g/100 g soil and 10 g/100 g soil) was compared with control. Among the test crops, maize with larger seeds was least sensitive to the exposure to various treatments while wheat and paddy with small seeds were comparatively susceptible. The incorporation of weed residue in soil had inhibitory effect on the per cent germination and shoot length of seedlings of test crops. The results of the study indicated the allelopathic influence of weed residue on the physiology of the crop plants. Therefore, the intensive studies on allelochemicals released from decaying weed residues in the natural environment where additive or synergistic effects become significant even at low concentrations are desirable to provide detail information on the influence of the weeds on crops of economic