Document Type : Research Paper

Authors

• Nasrin Biyabani ¹
• Vahid Abdossi ²
• Marziyeh Ghanbari Jahromi ³

¹ Department of Horticultural Science and Agronomy, Science and Research Branch, Islamic Azad University, Tehran, Iran.

² Department of Horticulture and Agronomy, Islamic Azad University, Science and Research Branch, Tehran, Iran

³ Department of Horticultural Science and Agronomy, Science and Research Branch, Islamic Azad University, Theran, Iran.

Abstract

Background and objectives: Salinity stress is one of the most significant abiotic stresses that impede agricultural production. It is often accompanied by oxidative stress due to the generation of reactive oxygen species (ROS). Mitigating the effects of environmental stress on plants through the use of growth-promoting compounds is of particular importance. In this context, silicon sources, such as potassium silicate, play a critical role in modulating salinity stress in plants. By enhancing plant resistance to salt stress, potassium silicate can contribute to improved growth and performance in areas with saline soils. These compounds promote cellular ion balance under adverse conditions and improve water uptake and retention in plants, thereby reducing ion leakage and the detrimental effects of salinity stress.
Methodology: The present study aimed to investigate the effect of potassium silicate on the growth and physiological and biochemical characteristics of goldenrod in a factorial design based on a completely randomized design with the factor of salinity stress at three levels (0, 60, and 120 mM) and foliar application of potassium silicate at three levels (0, 50, and 100 mg/l) under greenhouse conditions. Foliar application was carried out three times at 15-day intervals. The first foliar application was performed at the 4-leaf stage. After the second foliar application, salinity stress was induced by applying 200 milliliters of sodium chloride solution to each pot for 40 days. To prevent salt accumulation in the pots, all pots were rinsed with non-saline water after every 4 irrigations with saline water. The morphological variables investigated include wet and dry weight of shoots and roots and plant height and other traits including plant pigments (chlorophyll a, b and total), relative leaf water content, ion leakage rate, proline, sodium and potassium absorption rate of roots and it was the aerial parts that were measured in the middle of the golden grass flowering period.
Results: Salinity stress caused yield reduction, and potassium silicate moderated the negative effects of salinity stress and improved plant growth conditions. The evaluations showed that the salinity of 120 mM caused a decrease in the fresh weight of shoot (28%), dry weight of shoot (29%), fresh weight of root (38%), dry weight of root (37%), total chlorophyll (40%), the relative content of leaf water (17%), root potassium (14%) and leaf potassium (16%) and increased ion leakage (23%), proline (13%), root sodium (256%), sodium leaves (325%). Potassium silicate, especially 100 mg/l, moderated salinity stress by increasing plant weight, chlorophyll, leaf water, and potassium content in leaves and roots and reducing sodium accumulation in leaves and roots and ion leakage.
Conclusion: The general results of the research showed that increasing the intensity of salinity stress had negative effects on the growth and functional characteristics of golden grass and potassium silicate in the volume of 50 to 100 mM caused the adjustment of salinity stress by increasing the quantitative and qualitative performance (biochemical and phytochemical) of golden grass. Therefore, to cultivate the golden grass plant, it should be noted that the water or soil used does not contain salts such as sodium and chlorine, or soil conditioners or growth stimulants should be used for the production and cultivation of this plant.

Keywords

• Salinity stress
• proline
• growth promoter
• golden grass

Main Subjects

• Agriculture and horticulture