Evaluation of effects of different salinity levels in irrigation water for some cotton varieties under Southeastern Anatolia region conditions

This study was carried out to determine the effects of different salinity levels in irrigation water for some cotton varieties under Diyarbakır Province of Southeastern Anatolia Region in 2007. The experiments were realized in the metal containers like lyzimeter with drainage type. The treatments were 4 different salinity levels (T0: 0.32 dS/m, T1: 5 dS/m, T2: 9 dS/m ve T3: 13 dS/m) and 3 different cotton cultivars (P1: Berke, P2: Stonville-453 ve P3: Teks). According to the results, the levels of increasing salinity in irrigation water decreased the seed-cotton yield for all the cultivars. The least affected cultivar from the salinity was Berke. Compared to the cultivar of Berke, the seed-cotton yields of Stonville-453 and Teks were less 8.3 % and 23.1 %, respectively. The values of salinity threshold for irrigation water according to the cultivars of cotton were calculated as Ct=4.45 (Berke), Ct=4.32 (Stonville-453) and Ct=3.72 (Teks). The values of salinity threshold for soil were Ct=6.58 (Berke), Ct=7.46 (Stonville-453), Ct=6.84 (Teks). The results showed that there were no significantly loss seed-cotton yield when irrigation water salinity up to the values of 4.45 dS/m was used.