Endogenous Polyamines and Ethylene Biosynthesis in Relation to Germination of Osmoprimed Brassica napus Seeds under Salt Stress

Abstract

Currently, seed priming is reported as an efficient and low-cost approach to increase crop yield, which could not only promote seed germination and improve plant growth state but also increase abiotic stress tolerance. Salinity represents one of the most significant abiotic stresses that alters multiple processes in plants. The accumulation of polyamines (PAs) in response to salt stress is one of the most remarkable plant metabolic responses. This paper examined the effect of osmopriming on endogenous polyamine metabolism at the germination and early seedling development of Brassica napus in relation to salinity tolerance. Free, conjugated and bound polyamines were analyzed, and changes in their accumulation were discussed with literature data. The most remarkable differences between the corresponding osmoprimed and unprimed seeds were visible in the free (spermine) and conjugated (putrescine, spermidine) fractions. The arginine decarboxylase pathway seems to be responsible for the accumulation of PAs in primed seeds. The obvious impact of seed priming on tyramine accumulation was also demonstrated. Moreover, the level of ethylene increased considerably in seedlings issued from primed seeds exposed to salt stress. It can be concluded that the polyamines are involved in creating the beneficial effect of osmopriming on germination and early growth of Brassica napus seedlings under saline conditions through moderate changes in their biosynthesis and accumulation.

Green Synthesis of Hyperbranched Spermine-Coated Fe3O4 Nanoparticles and Their Effect on Corn Seedlings under Copper Oxide Stress

“…Corn germination results showed that coating of Fe 3 O 4 -NPs by HS improved seed germination characteristics due to the increased activity of decomposing enzymes related to germination, such as γ-amylase, and increased DNA and RNA synthesis. The hydrolysis of protein and carbohydrates by specific enzymes such as proteases α-and β amylases contributes to the GR, which could be a justification for speeding up the GR and reducing the MGT. ,, …”

“…47 This could be due to enhanced seed coat permeability, allowing more water to enter the cells, and increasing metabolism and germination. 44 A similar observation has been reported in several works. 15,43,45,46 Effects of Hyperbranched Spermine and Hyperbranched Spermine-Coated Fe 3 O 4 on Germination of Corn.…”

“…It has also been reported that seed priming with Fe 3 O 4 -NPs has an effect on germination, and the application of 20 mg/L of iron oxide enhanced the percentage of rice germination and decreased the MGT . This could be due to enhanced seed coat permeability, allowing more water to enter the cells, and increasing metabolism and germination . A similar observation has been reported in several works. ,,, …”

“…42 Studies on canola and rice showed an increase in polyamine concentration during the early stages of germination, which is consistent with the current study. 43,44 Spermine application has been reported to have a positive effect on V. radiata seed germination. In addition, spermines are involved in the release of seed dormancy.…”

“…Seed germination is an extremely dynamic process that necessitates metabolic activation, organellar structure biogenesis, stored substance mobilization, cell elongation, replication, and cell division . Studies on canola and rice showed an increase in polyamine concentration during the early stages of germination, which is consistent with the current study. , Spermine application has been reported to have a positive effect on V. radiata seed germination.…”