TO INVESTIGATE THE MAJOR WEEDS OF WHEAT IN DIFFERENT AGRO-ECOLOGICAL ZONES OF KHYBER PAKHTUNKHWA PAKISTAN

Weed infestation of wheat crop is a serious problem throughout the country as weeds cause huge yield losses. To investigate the major weeds of wheat in Khyber Pakhtunkhwa province, a comprehensive survey was conducted during January to June, 2012. Wheat fields at D.I. Khan, Lakki Marwat, Kohat and Peshawar were visited. Surveys were conducted when the growth of the weeds was at peak. Quadrate method was used to record relative density, relative frequency, relative canopy coverage and importance value index. Several fields were visited at each location and the data average was calculated. After putting the data in ecological formulae, the data obtained showed Avena fatua as a major weed of wheat at the above mentioned four locations. While, Rumex dentatus at D.I. Khan, Phalaris minor at Lakki Marwat and Peshawar, and Rumex crispus at Kohat were the second major weeds after A. fatua. During these comprehensive surveys, the major and most problematic weeds of wheat were identified and the importance value indices were calculated. The seeds of two major weeds that ranked first and second at each location were collected at maturity and thus were used for detailed experimentations.