A FLORISTIC STUDY ON THE WEEDS OF WHEAT FIELDS OF ZANJAN PROVINCE, IRAN

Weed is one of the most important factors that decrease yield and quality of wheat crop, therefore identification of weeds is so valuable in its management strategies. Availability of weeds information of a specific region will aid us select the best method for control and manage them in our planning. Due to existence of so many different weed species in wheat fields of Zanjan province (Iran), this survey was conducted to cover seven different areas selected randomly from different locations of the province during 2003-04. In each field, 9 to 13 plot samples with a W pattern were located at three different grow stages of wheat i.e. tillering, stem elongation and heading. The species of the weeds were mostly determined based on Flora Iranica. According to this study, 126 angiospermous taxa of 107 genera in 30 families were recorded as weeds from the Zanjan province. All of the recorded specimens were donated to FAR Herbarium. The largest families were Brassicaceae (including 24 species, making 16.3% of the total), Poaceae (22 species, 14.9%), and Asteraceae (17 species, 11.5%). Among them, 24 families belonged to dicotyledons and seven families were monocots.