EFFECT OF OSMO-HARDENING SEED ON K AND NA CONCENTRATION AND SOME GROWTH PROPERTIES OF WHEAT UNDER SALT STRESS

Abstract

Salinity is a major abiotic stress, limiting plant growth and agricultural productivity worldwide. It is known that plant growth regulators mitigate the negative effects of salinity. The current study showed the effect of 6-benzyl aminopurine, gibberellin and melatonin on wheat, which is a moderately tolerant crop to salinity, and it is grown for grain as it is a major crop for most countries of the world. A field experiment was conducted using three cultivars of wheat (Al-Ezz, Dijlah, and Al-Rasheed) under the influence of five combinations of tempering seeds before planting (Seed Hardening with salts (comparison 2), Seed Hardening + Benzyl stimulation, Seed hardening + Gibberellin stimulation, Seed hardening + Melatonin stimulation), all of them. It was irrigated with salty well water (6 dS Siemens m 2 m) in addition to the treatment (comparison 1) that was not subjected to hardening and stimulation and was irrigated with river water. The potassium and sodium content of the leaves were evaluated, The Dijlah and Al-Rasheed cultivars had the highest potassium content 3.40 and 3.10, while the Ezz cultivar had the highest sodium content of 0.238. The area of the flag leaf, the number of branches and the biological yield of Al-Rashid cultivar increased (19.6 cm2 and 43.6 branch cm2 and 126.06g cm-2), while the Dijlah cultivar achieved the highest root weight of 0.568 gm. The combinations of salinity treatment (hardening + melatonin) increased the area of the flag leaf and the concentration of potassium in the leaves and decreased the sodium element (14.03 cm-2, 3.866 and 0.167), Thus,it was superior to the comparison treatment 1 that was not exposed to saline stress, and this was positively reflected on the rest of the studied traits. It turns out that melatonin can relieve salt stress in plants by affecting metabolic or physiological processes. The application of melatonin is an effective management strategy to mitigate salt stress in order to increase agricultural production and sustainability.