Antioxidative and Metabolic Contribution to Salinity Stress Responses in Two Rapeseed Cultivars during the Early Seedling Stage

Abstract

Measuring metabolite patterns and antioxidant ability is vital to understanding the physiological and molecular responses of plants under salinity. A morphological analysis of five rapeseed cultivars showed that Yangyou 9 and Zhongshuang 11 were the most salt-tolerant and -sensitive, respectively. In Yangyou 9, the reactive oxygen species (ROS) level and malondialdehyde (MDA) content were minimized by the activation of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) for scavenging of over-accumulated ROS under salinity stress. Furthermore, Yangyou 9 showed a significantly higher positive correlation with photosynthetic pigments, osmolyte accumulation, and an adjusted Na+/K+ ratio to improve salt tolerance compared to Zhongshuang 11. Out of 332 compounds identified in the metabolic profile, 225 metabolites were filtrated according to p < 0.05, and 47 metabolites responded to salt stress within tolerant and sensitive cultivars during the studied time, whereas 16 and 9 metabolic compounds accumulated during 12 and 24 h, respectively, in Yangyou 9 after being sown in salt treatment, including fatty acids, amino acids, and flavonoids. These metabolites are relevant to metabolic pathways (amino acid, sucrose, flavonoid metabolism, and tricarboxylic acid cycle (TCA), which accumulated as a response to salinity stress. Thus, Yangyou 9, as a tolerant cultivar, showed improved antioxidant enzyme activity and higher metabolite accumulation, which enhances its tolerance against salinity. This work aids in elucidating the essential cellular metabolic changes in response to salt stress in rapeseed cultivars during seed germination. Meanwhile, the identified metabolites can act as biomarkers to characterize plant performance in breeding programs under salt stress. This comprehensive study of the metabolomics and antioxidant activities of Brassica napus L. during the early seedling stage is of great reference value for plant breeders to develop salt-tolerant rapeseed cultivars.

Comparative efficacy of bio-selenium nanoparticles and sodium selenite on morpho-physiochemical attributes under normal and salt stress conditions, besides selenium detoxification pathways in Brassica napus L.

“…To investigate the effect of bioSeNPs and Se (IV) on B. napus under standard and salt stress conditions, 60 sterilized seeds were placed on filter paper in the germination boxes (15 × 10 × 5 cm), containing 15 mL of different solutions, ddH 2 O as a control and 50, 100 and 150 µmol L −1 Se (IV) or bioSeNPs (standard conditions), ddH 2 O, 150 and 200 mM NaCl as a control, 50, 100 and 150 µmol L −1 Se (IV) or bioSeNPs combined with 150 and 200 mM NaCl (salt stress conditions). Three replicates of seeds were kept according to a randomized block design in a growth chamber with optimal conditions (day/night temperature at 25 ± 1/20 ± 1 °C) with 12 h light (13,000 lx) and 12 h dark (HP250GS-C, Ruihua Instrument and Equipment Co., Ltd., Wuhan, China) according to [ 33 ]. Germinated seeds were counted daily, starting from the first day of cultivation to the seventh day; seeds were considered germinated when the primary root was at least 2 mm long.…”

Deciphering Reserve Mobilization, Antioxidant Potential, and Expression Analysis of Starch Synthesis in Sorghum Seedlings under Salt Stress

“…Accumulation of higher concentrations of inorganic cations such as sodium, magnesium, and calcium, and anions such as chloride and sulfate, disturb the membrane potential [12]. The high concentration of salts in the soil has a destructive effect on the cell membrane's integrity, photosynthetic reactions, activation of several proteases, and absorption of nutrients [13]. Excess salts compromise the physiological and biochemical functions of plants, causing osmotic stress that results in disturbances of water conductance [2].…”

Salt Priming as a Smart Approach to Mitigate Salt Stress in Faba Bean (Vicia faba L.)

“…They prevent free radicals from diffusing into the membrane's hydrophobic matrix and/or restricting oxidative stress-induced reactions in the bilayer's hydrophobic region [73]. The increase in phenolics in response to salt stress was also recorded in faba bean [44], wheat [74], and rapeseed [75].…”