FLORISTIC COMPOSITION AND ECOLOGICAL PREVALENCE OF THE WEED SPECIES GROWING IN WHEAT AND SUGAR CANE FIELDS OF DISTRICT CHARSADDA, KHYBER PAKHTUNKHWA, PAKISTAN

A total of 43 weed species belongs to 17 families and 39 genera were collected from wheat and sugarcane fields. Among them 3 genera and 3 species were monocot and 36 genera and 40 species were dicot. Family Asteraceae was the leading family represented by 11 genera (28.2%) and 12 species (27.9%). Brassicaceae, Caryophyllaceae, Papilionaceae having 4 genera (10.3%) and 4 species (9.3%) each. Poaceae having 3 genera (7.7%) and 3 species (6.97%), Polygonaceae having 2 genera (5.12%) and 3 species (6.97%). While the remaining families having 1 genera (2.6%) and 1 species (2.33%) each. According to lifeform classification Therophytes were the major lifeform class (93%) and Hemicryptophytes were 4.7% and Chamaephytes were 2.3%. Leaf size classification shows that Microphylls (37.2%) were the major leaf size class followed by Leptophylls (30.2%), Nannophylls (16.3%) and Mesophylls (16.3%). The weed species are competing with crops for nutrients, space, light and interfere by inhibiting nutrients uptake by the plants thus resulting in to considerable decrease in crop productivity.