Effect of spraying with Nano nitrogen and potassium on some Morphological Characteristics of Calendula officinalis L. plant under water stress conditions

Abstract

An experiment was carried out in plastic pots in the College of Agriculture , University of Kerbala, to investigate the effect of foliar spraying with Nano nitrogen and potassium on some phenotypic characters of Calendula officinalis L. under the water stress condition in sandy loam soil in winter growing season (2023-2024). Factorial experiment in a CRD with 3 replications was used for the study. The experiment consisted of three factors with three replicates. The first factor consisted of two levels of irrigation water levels (50% and 100% of soil field capacity) denoted as S1 and S2 (Table 1). The second factor was foliar application using three levels of liquid Nano nitrogen fertilizer (0, 2 and 4 ml) L-1, denoted as N0, N1, and N2 respectively. The third factor was foliar application of the complex Nano-potassium fertilizer at three concentrations, 0, 2, and 4 g L-1, designated K0, K1, and K2, respectively. These levels were randomly assigned to all experimental units. The design involved 54 experimental units. Data were subjected to statistical analysis as per the design adopted and means were compared at 5% level of probability. The results indicated a significant impact of the factors examined in this study, as well as their interactions, on various phenotypic traits, including plant height, stem diameter, number of leaves, and number of flowers. The average values of these traits decreased under conditions of water stress when irrigation was applied at 50% of the soil field capacity. Additionally, the values further declined with lower concentrations of foliar spray containing Nano nitrogen and potassium