ALLELOPATHIC EFFECTS OF SUNFLOWER WATER EXTRACT ON WEED CONTROL AND WHEAT PRODUCTIVITY

Allelopathic influence of sunflower plant waterextract (1:10 w/v) against weeds and wheat sown aftersorghum crop was studied under field conditions atFodder Research Institute, Sargodha (Pakistan), during2005-06. Treatments applied were sunflower plantwater extract at pre-emergence, at 25 DAS (days aftersowing), pre-emergence + 25 DAS, 25+35 DAS, preemergence+ 25 + 35 DAS and control. Wheat varietyInqlab-91 was sown on 13th November, 2005. Theinhibitory effects of pre-emergence application ongermination of Phalaris minor were higher, whereaswheat remained unaffected at this stage of application.Application of water extract at pre-emergence + 25DAS, 25 + 35 DAS and pre-emergence + 25 + 35 DASsuppressed the growth of Phalaris minor Retz.,Chenopodium album L., Coronopus didymus L. andAvena fatua L. Inhibitory effects were species specificand increased with increasing the water extractapplication frequency. All the treatments except preemergence+ 25 + 35 DAS increased the wheat yieldsignificantly over control.