Evaluation of effect of salinity stress and foliar spraying of spermine, spermidine and putrescine on leaf and root nutrients in Camelina

Soil salinity, especially in arid and semi-arid regions, is one of the factors that limit the growth of plants. Excessive accumulation of sodium and chloride ions leads to reduced growth and imbalance of nutrients. The use of exogenous polyamines, including putrescine, spermidine and spermine, is considered as an effective method not only in determining their role in response to salinity, but also as a way to increase plant resistance to salinity. Camelina is an oilseed product of the Brassica family, which contains other bioactive compounds such as flavonoids and phenolic products and as a new source of essential fatty acids, especially omega-3 fatty acids. This study was conducted with the aim of evaluating the effect of different levels of sodium chloride and foliar spraying of spermine, spermidine and putrescine on seed yield and the concentration of leaf and root nutrients in Camelina plant. The experiment was carried out in March 2022 as factorial design based on a completely random design (CRD) in the form of pot culture with 12 treatments and 3 replications. The salinity stress treatment was with Urmia lake water at three levels (0, 15, 30 ds/m). Foliar treatment at 4 levels 1- Foliar spraying with spermine (2 mM), 2- Foliar spraying with spermidine (2 mM), 3- Foliar spraying with putrescine (2 mM) and control (no foliar spraying). The application time of foliar spraying was done every 3 days (totally in 6 stages) after establishing three seedlings in the pot and reaching the four-leaf stage. At the end of the Camelina plant growth season, to calculate the seed yield, the seeds in the capsules of three plants in each pot were separated and weighed. Statistical analysis of data was done using SAS software (version 9.1) and MATATC, and comparison of means was also done by Tukey's test at the five percent level. Excel program was also used to draw graphs. The results of this research showed that the salt stress was 30 and 15 ds/m compared to the treatment without salt decreased leaf potassium (52 and 17%), root potassium (44 and 37%), leaf magnesium (50 and 28%), root magnesium (56 and 24%), leaf zinc (58 and 47%), root zinc (39 and 29%), leaf iron (10 and 2%), root iron (57 and 23%) and seed yield (52 and 10%), but it increased the amount of leaf sodium (89 and 82%), root sodium (39 and 11%), leaf calcium (14 and 6%) and root calcium (76 and 28%), respectively. Also, salinity stress caused a decrease in the ratio of potassium to sodium absorption, but increased the ratio of calcium to the sum of sodium and potassium in the roots and leaves due to the increase in the amount of sodium and the decrease in potassium. At all salinity levels, foliar spraying with polyamines increased leaf and root potassium, leaf and root magnesium, leaf and root zinc, leaf and root iron, by reducing the amount of sodium in leaves and roots. Also, foliar spraying with spermine, spermidine and putrescine compared to no foliar spraying, increased the seed yield by 32, 8 and 21%, respectively. The results of this research showed that foliar spraying with spermine, spermidine and putrescine by improving the absorption of macro and micro elements in roots and leaves, increasing the ratio of potassium to sodium and the ratio of calcium to total sodium and potassium in roots and leaves could moderate the effects of salinity stress and improve the seed yield of camellia under salinity stress conditions and it prevented excessive reduction in seed yield.