Calcium nitrate on growth and ornamental traits at salt-stressed condition in ornamental kale (Brassica oleracea L. var. Acephala)

Abstract Ornamental plants are used to improve the aestheticquality of urban and rural landscapes, recreational areas, interiorscapes and commercial sites. Any negative effects of salts on ornamental plant growth have to be taken into consideration mainly for their negative influences on aesthetic value of ornamental plants. The research was conducted to determine the effects of different concentrations of calcium nitrate on some stress parameters (i.e. leaf relative water content, chlorophyll, stomatal conductance, ion leakage in the leaf tissues) and some plant growth parameters (total leaf number, number of dried leaf, main stem diameter, plant crown diameter, plant height, fresh and dry weight of root) of ornamental kale (Brassica oleracea L. var. acephala) plant grown under saline conditions. Four doses of NaCl (NaCl1:30, NaCl2:60, NaCl3:90, NaCl4:120 mM), three doses of Ca(NO3)2 (CaN1:5, CaN2:10, CaN3:15 mM), groups combined together in all doses of NaCl and Ca (NO3)2 and control (NaCl0:0 + CaN0:0) were applied into the pots with three replications. Ca (NO3)2 was applied to the leaf surface of the plants in the pots to be applied as Ca (NO3)2 spray. When the plants reached a certain maturity (two weeks after transfer to the pot), salt stress applications were started. Ca (NO3)2 treatments have applied after one week from salt stress applications. Calcium nitrate treatements applied under salt stress conditions had positive effects and increasing in effect on all parameters examined except for chlorophyll and ion leakage in leaf tissues of the plant. With increasing in calcium nitrate concentration, morphological and physiological characteristics of plants were observed increases in general. It was concluded that the increase of the number of leaves by NaCl2+CaN3 application can be minimized with CaN3 (with 15 mM Ca (NO3)2) stress caused by 60 mM salt concentration According to the results of the research, calcium nitrate applications can be recommended for ornamental kale plants grown under salt stress conditions especially limiting the negative effects of stress and to minimize such damage.