Changes of micronutrients, dry weight and plant development in canola (Brassica napus L.) cultivars under salt stress

Abstract

This study was carried out to determine the effects of salt stress on the growth, dry weights and micronutrient contents of canola (Brassica napus L.) cultivars grown in greenhouse conditions. 12 canola cultivars (Marinca, Kosa, Spok, Semu DNK207 NA, Tower, Liraspa, Star, Tobin, Helios, Semu 209/81, Regent and Lirawell) were exposed to salinity treatments (150 mM NaCl and control). Shoot, leaf and root dry weights of all the cultivars at 45-day-old plants were determined. Micronutrient contents (Fe, Mn, Cu and Zn) of the leaves, stems and roots were also analyzed. Salinity stress negatively affected the canola cultivars and the extent of effects varied depending on the salt tolerance of the cultivars. Generally, salinity reduced the plant growth and dry weights. Fe, Mn, Cu and Zn concentrations were high in the roots when compared with those in the leaves and shoots in the salt applied samples. It was observed that, micronutrient contents showed some variation in the different plant parts of the canola cultivars as a result of salt applications to the growing media. Iron (Fe), manganese (Mn) and copper (Cu) content increased in all the plant parts with salt applications except for some cultivars. On the other hand, when mean data of the cultivars were considered, it could be said that zinc (Zn) content of the leaves was not significantly affected by the salt stress.

Key words: Canola, Brassica napus, dry weight, micronutrient accumulation, salt stress.