Effect of Irrigation Water Salinity Concentrations and Methyl jasmonate on Vegetative and Laboratory Growth Characteristics of Sunflower Crop

Abstract

Two experiments were conducted, one in the field and the other in the laboratory. The field experiment was conducted in the fields of the Crop Science Department, College of Agriculture - Anbar University, in Ramadi district, Anbar province, during the autumn season of 2023/2024, to study the effect of methyl jasmonate concentrations and irrigation water salinity on the vegetative growth traits of sunflower crop. The field experiment was conducted in the fields of the Department of Field Crops, College of Agriculture, University of Anbar, in Ramadi District, Anbar Governorate, The experiment was designed as a factorial experiment (two factors) according to a randomized complete block design (R.C.B.D) with three replicates, each replicate containing 16 experimental units. The laboratory experiment was conducted in the Plant Protection Department laboratory - College of Agriculture - Anbar University, with the aim of studying the effect of soaking sunflower seeds in methyl jasmonate and saline irrigation water on the laboratory traits of sunflower plants. The experiment was conducted using a completely randomized design (CRD) with two factors. The first factor was seed soaking with methyl jasmonate at three concentrations (1, 2, 3 mM) along with a control treatment (distilled water + ethanol solution), and the second factor was saline irrigation water at four concentrations (2, 4, 6, 8 dsi m-1). Concentration 1 (mM) of methyl jasmonate showed superiority in all studied field traits: plant height, leaf area, and stem diameter, with respective averages of 36.70, 27.814, and 8.050. While, concentration 3 mM achieved the lowest average for all mentioned traits, with means of 28.41, 18.672, and 4.145, respectively. Similarly, The concentration of 1 mM also excelled in all studied laboratory traits, germination rate, final germination percentage, root length, and shoot length with an average of (84.2, 96.25, 11.35, 13.60), respectively, while the concentration of 3 mM achieved the lowest average for the germination rate, root length, and shoot length with an average of (46.6, 6.24, 8.18), respectively. The control treatment (0) achieved the lowest average for the final germination percentage, with a mean of 85.42%. Regarding salinity levels, the concentration (4 dS.m-1) outperformed in all studied field and laboratory traits, while the concentration 8 dS.m-1 recorded the lowest average for all studied field and laboratory traits. The highest value for the activity of SOD and POD enzymes was (1082.8, 4.4835) at the concentration of 3 mM methyl jasmonate, and the lowest average for these enzymes at the concentration of 1 mM was (772.2, 3.7250). Regarding the salinity levels, the concentration of 8 dS.m-1 achieved the highest average for the activity of SOD and POD enzymes with an average of (1428.5, 5.3803), respectively, while the concentration of 4 dS.m-1 achieved the lowest average for these enzymes with an average of (693.5, 3.3054), respectively.