Effects of the nano silicon application on salt tolerance in pepper (Capsicum annuum L.)

In the study, in which the effectiveness of nano-silicon (Nano-Si) applications for increasing salt tolerance in pepper was investigated, commercial varieties of Mızrak and Şölen were used as materials. For stress plants, 4 different salt doses, 0 (control), 50, 100 and 150 mM, were used in 3 true leaf stages, and 0, 0.5, 1, 2 and 3 mM doses were used together with salt stress in Nano-Si applications. It was applied once as a foliar spray. Plants harvested after stress, green part fresh and dry weight, stem length and diameter, leaf number and area, leaf water proportional content (YOSI), green part Na, Cl, K and Ca content, malondialdehyde (MDA), chlorophyll-a , b, were examined for total chlorophyll and carotenoid content. Salt stress caused a decrease in plant growth parameters, YOSİ, K and Ca ion concentration, chlorophyll-a, b, total chlorophyll and carotenoid content in pepper varieties; Na and Cl ion concentration and MDA content increased. This increase became evident in parallel with the increase in salt level, and damage was observed at the maximum dose of 150 mM. On the other hand, in nano-Si applications with salt stress, on average 9-82% in wet and dry weight compared to salt stress; 16-91% in stem length and diameter; 23-92% in number and area of leaves, 15-37% in YOSI values; 1-41% in K content; 13-75% in Ca content; 9-87% improvement was achieved in photosynthetic pigments. In addition, while Na ion uptake is limited to 16-33%, Cl ion uptake is limited to 11-23%; The increase in MDA content was prevented at the level of 20-258%. As a result of the study, it was determined that nano-Si applications improved the damage caused by salt stress at varying rates and were effective in increasing tolerance, and 0.50 mM and 1.00 mM nano-Si applications came to the fore in terms of this positive effect among the applications.