Comparative Weed Density Studies in Irrigated Carrot (Daucus carota L.) Potato (Solanum tuberosum L.) and Wheat (Triticum aestivum L.) in Sokoto-Rima Valley, Sokoto State, Nigeria*

A.I., Yakubu, J. Alhassan, A. Lado and S. Sarkindiya

Journal of Plant Sciences 5 ( 1 ): 33 - 40 , 2010