Determination of Weed Problems in Three Different Growing Seasons in Potato Fields (Solanum tuberosum L.) in Odemis District of Izmir

This study was conducted to determine the disribution and density of weed species which are problems on potato fields located in central odemis and its district in 2014. Survey studies were made between April and October; periods of spring, summer an autumn; on total 70 fields. As a result of the survey, 44 diffrent weed spesies from 23 families were identified. The weeds in each sampling frame were counted, and their frequency and density were determined. The most commonly found families were Poaceae (9 species), Polygonaceae (5 species), Brassicaceae (3 species) and Asteraceae (3 species) respectively. In spring time, Chenopodium album before cultuvation and Portulaca oleraceae after cultuvation were detected as the most dense seen species. Chenopodium album were determined as the most frequently seen species, before and after cultuvation, in terms of frequency of occurence. In summer time, Echinochloa crus-galli were detected, before and after cultuvation, as the most dense and frequently seen species. In autumn time, Portulaca oleraceae, was found before cultuvation and Chenopodium album was found after cultuvation as the most dense species. Portulaca oleraceae was the most frequently seen species both before and after the cultuvation. Keywords : Potato, weed, density, survey