The salinity impact on changes in some metabolites and some vital subcellular organelles in white maize

Abstract

Abstract Background The great need to propagate new crop genotypes that are well adapted to the changing environmental conditions is urgently needed to support the high demand of food of the growing world population. In this work five white maize inbred lines (P4, P8, P12, P15, and P17) were studied for their salinity tolerance when exposed to: 0, 1000, 2000, 3000, and 10000 mg/L NaCl. The equilibrium balance between reactive oxygen species ROS and the detoxification cascades points to the plant’s performance under stress. The free amino acid and soluble sugar contents (non-enzymatic antioxidants) in addition to the superoxide dismutase & Phenylalanine ammonia-lyase SOD& PAL (enzymatic antioxidants) and some phenolic compounds contents were evaluated against hydrogen peroxide H2O2 as ROS product to classify plants to stress -tolerance or sensitive. Transmission electronic microscope (TEM) investigation is also, used to study the impact of the stress on the plant cells’ compartments after the direct treatment with saline water for 3 h as moderate soil holding time capacity to irrigation water. Results Maize line P8 followed by line P17 were the highest to cope with the irrigation of saline water in different ranges of concentrations of salt, accumulate the soluble sugars, free amino acids and antioxidants over control and other maize lines. These results are supported by the root ultrastructure observation with transmission electronic microscope. Conclusion Maize line P8 followed by the P17 line are highly recommended to be crossed and planted in the newly reclaimed lands irrigated with salty water. Graphical Abstract

Keywords

• Biochemical markers
• Antioxidant enzymes
• Non-enzymatic detoxification
• TEM investigation
• Salinity