Effects of salt source and irrigation water salinity on growth, yield and quality parameters of black cumin

Abstract

Excess salinity, osmotic stress, toxic ions and ion imbalance negatively affect plant growth. Many crops are classified as salt sensitive. However, there is no information in the literature about the effects of different salt sources (SS) and salinity levels (SLs) on black cumin (Nigella sativa L.). This study was conducted to determine the effects of SL (0.6, 1.5, 2.5 and 5.0 dS/m) prepared separately by different SSs (CaCl2, MgCl2, NaCl, Ca(NO3)2, MgSO4 and Na2SO4) on the evapotranspiration, growth, yield and quality parameters of black cumin. The results showed that the evapotranspiration, soil salinity, plant height, vegetative dry weight and oil content of black cumin were affected only by SL. Both SS and SL have a significant effect on the number of capsules and seed weight. The SS × SL interaction was meaningful on drainage water salinity and the number of seeds. The seed weights under CaCl2, MgCl2, Ca(NO3)2, MgSO4 and Na2SO4 SS were adversely affected even at very low SL. However, the low slope values for these salts reveal that the increase in SL has a limited effect on seed weight. Therefore, it can be recommended to consider both the salt type and SL of irrigation water in black cumin cultivation.