Farklı kalsiyum dozları ve tuz seviyelerinin domateste (Solanum lycopersicum L.) verim, kalite ve çiçek burnu çürüklüğüne etkisi

Salinity is one of the most important problem in tomato production. Tomato is moderately salt-sensitive crops, and significant yield and quality losses occur under salt stress. One of the most important effect of salt stress is that it causes blossom end rot in tomato fruit. The reduced uptake of calcium by tomato plants under salt stress leads to the development of blossom end rot. Calcium is one of the effective nutrients in reducing the negative effects of salt stress in tomato plants. This study was carried out in a greenhouse at the Gaziosmanpaşa University, Agricultural Faculty, Department of Horticulture, Tokat/Türkiye, from 01 May to 10 December 2021 and from 10 May to 30 November 2022. Plants were grown in soilless culture. Cocopeat + perlite mixture (2:1 ratio) was used as growing media. Ufuk Fı indeterminate tomato variety and LA442 tomato line were used. In the experiment, interactions between different calcium doses and salt levels were tested. Four different calcium oxide doses (0, 50, 100, and 200 ppm) and three salinity levels (2.0, 4.0, and 6.0 dS/m) were used. The plants were regularly watered with irrigation water containing salt and calcium. Irrigation water containing calcium was given at 08.00, while, irrigation water containing salt was given at 16.00. The results showed that in the years 2021 and 2022 for the LA442 and Ufuk Fı genotypes, increasing calcium doses from 0 to 200 ppm significantly increased marketable fruit yield, marketable fruit weight, total yield and fruit number in both saline and non-saline conditions. Marketable yield, total yield and marketable fruit weight were maximized at 200 ppm calcium application in both years and two varieties at high salt concentration. As the salinity of the nutrient solution increased, the incidence of blossom end rot increased, and as the Ca dose increased, the rate decreased. Increasing the Ca dose at high salt concentration resulted in a significant decrease in blossom end rot. Increasing salt concentration caused an increase in Brix in the fruit, and no significant relationship was found between Ca doses and Brix. While salt stress caused a decrease in leaf chlorophyll content, the amount of chlorophyll content increased as the Ca doses increased. Fe and Mn content of tomato leaves decreased due to increase in salt and Ca. Leaf Fe content decreased as salinity and Ca doses increased. While P and K decreased in high salinity, no relationship was found between leaf P and K content with calcium doses. While leaf Na content increased with increasing salt, no significant relationship was found with Ca doses. The amount of Ca in tomato fruits, Ca of leaf and also in the tip of the fruit decreased as salt increased and increased as calcium increased. Vitamin C in fruit was negatively affected by salt stress, and the increase in Ca doses increased. Salinity effected fruit enzyme activity. While MDA, APX, CAT and POX activities in fruit increased under salt stress, high Ca dose caused a decrease or did not change in some applications. As a result, salt stress in tomato caused a significant decrease in plant development, yield and quality parameters, but high concentrations of Ca doses to plants under salt stress significantly reduced the effect of salt stress. A significant portion of the yield and quality loss was caused by blossom end rot in fruits. While blossom end rot increased in salt stress, giving high doses of Ca to plants under stress significantly reduced blossom end rot.