@article{article_1619161, title={Effect of Different Irrigation Levels on Some Lettuce (Lactuca sativa) Varieties Grown in Kocaeli Conditions}, journal={Bursa Uludağ Üniversitesi Ziraat Fakültesi Dergisi}, volume={39}, pages={129–142}, year={2025}, DOI={10.20479/bursauludagziraat.1619161}, author={Güvenaltın, Yusuf and Kuşçu, Hayrettin}, keywords={Curly and head lettuce, deficit irrigation, yield, evaporation}, abstract={In this study, the effects of different irrigation levels on some lettuce cultivars were investigated. The research was conducted under greenhouse conditions in Kocaeli province during the 2020-2021 growing season. In the experiment, a split-plot design in randomized blocks was used. Varieties (Carteganas, Concorde, and Melina) were in the main plots, and five irrigation levels (0.25 E, 0.50 E, 0.75 E, 1.00 E, and 1.25 E) were created by taking the amount of water evaporated (E) from a 100 ml glass petri dish as a reference in the sub-plots. Head weight, diameter, length, root length, and leaf number values showed statistically significant (P <0.01) differences according to variety (V), irrigation level (IL), and V x IL interactions. The highest average head weight was obtained as 516.9 g in the Melina variety, followed by the Concorde and Carteganas varieties. The highest average head weight was obtained from 0.75 E at 581.2 g, while the lowest was obtained from 0.25 E at 224.8 g. The highest values in all yield components were obtained from the 0.75 E irrigation level. Relatively low values were obtained at 0.25 E and 0.50 E irrigation levels. According to the results obtained, the appropriate lettuce variety can be selected by considering the market value, and Melina, which has a higher unit mass, can be preferred. In addition, it was concluded that small petri dishes could be used in planning the irrigation time for lettuce grown in unheated greenhouse conditions in Kocaeli, and it can be recommended to use a value of 0.75 as the crop-pan coefficient.}, number={1}, publisher={Bursa Uludağ University}