Effect of Hydrogen Peroxide and Soil Amendments on the Physiological Characteristics of Ranunculus Asiaticus in Saline Soils

Abstract

This study was conducted in a greenhouse at research station (A) of the College of Agricultural Engineering Sciences - University of Baghdad - Jadiriyah during the autumn season of 2020 to study the impact of exogenous application of hydrogen peroxide and soil amendments (zeolite and Disper osmotic regulator) and their interactions in the physiological traits of the Ranunculus asiaticus L. grown in saline soils. The experiment was carried in a split-split block (2*5*3) according to an RCBD randomized complete block design with three replications and an average of 6 plants in the experimental unit The results showed that the growth of Ranunculus asiaticus L in saline soils caused a significant decrease in the leaf content of relative water content (RWC), membrane stability index (MSI), chlorophyll content. While a significant increase in the leaf content of hydrogen peroxide was observed, and the increase in the electrolytic leaching of the plant is an indicator of oxidative stress. The addition of soil amendments to plants grown under salinity stress caused a significant increase in the leaf content relative to water content, membrane stability, decreased electrolytic leaching, and hydrogen peroxide content. Exogenous application of hydrogen peroxide at a concentration (5 mmol l-1) had a positive effect on most of the physiological characteristics. The interaction between soil amendments and hydrogen peroxide contributed to the avoidance of plants from oxidative stress resulting from the high concentration of effective oxygen radicals (ROS) in the cells of plants exposed to salt stress, and stimulating the activity of the enzymatic and non enzymatic defense system in addition to the increase of chlorophyll and physiological characteristics.