Deserts comprise about 95% of the total land surface of Egypt; therefore, their potential for production must be assessed. Weed communities are mainly affected by the environment, and studies may increase our knowledge of the relationship among the weed flora, soil properties, crop rotation, soil management, fertiliser usage, and weed control. | Turkish Journal of Botany Turk J Bot (2013) 37: 464-488 © TÜBİTAK doi: Research Article Weed flora in the reclaimed lands along the northern sector of the Nile Valley in Egypt 1 1 1, 2 Monier ABD EL-GHANI , Ashraf SOLIMAN , Rim HAMDY *, Ebtesam BENNOBA 1 Department of Botany, Faculty of Science, Cairo University, Giza, Egypt 2 Department of Botany, Faculty of Science, 7th April University, Zawiya, Libya Received: Accepted: Published Online: Printed: Abstract: Deserts comprise about 95% of the total land surface of Egypt; therefore, their potential for production must be assessed. Weed communities are mainly affected by the environment, and studies may increase our knowledge of the relationship among the weed flora, soil properties, crop rotation, soil management, fertiliser usage, and weed control. The area under study is one of the most recently reclaimed lands. The recorded 150 species in the monitored 19 sites were distributed within 33 families. The species-rich families were: Poaceae (31), Asteraceae (23), Brassicaceae (13), Chenopodiaceae (12), and Fabaceae (12). Chorological analysis revealed that the widely distributed species belonging to cosmopolitan, palaeotropical, and pantropical chorotypes constituted about of the recorded flora. Pure Mediterranean species were very poorly represented, while biregional and triregional Mediterranean chorotypes constituted 28%. Saharo-Arabian chorotypes, either pure or penetrated into other regions, constituted 32%. Ubiquitous species with wide amplitude were Cynodon dactylon (L.) Pers. and Sonchus oleraceus L. Species richness varied from one crop to another. The winter weeds represented the main bulk of the recorded species within each crop, desert perennials exhibited notable variations, and margin species were the lowest. Redundancy analysis demonstrated the effect of soil organic matter, coarse .