Evaluation of the chemical content of water-stressed goldenrod plant under the influence of tissue polyter and nano-chitosan

Abstract

Abstract An independent factorial experiment was conducted in one of the plastic greenhouses designated for this purpose in Karbala, Al-Husseiniya district, located 14 km from the city center, during the 2024–2025 agricultural season. The aim was to study the effect of natural compounds on the chemical content of goldenrod plants subjected to water stress under greenhouse conditions. The experiment involved three factors: the first factor was water stress, i.e., irrigation at three intervals (every 4, 6, and 8 days); the second factor was the use of tissue politer at three levels (0, 2.50, and 5 g pot⁻¹), applied once at seedling transplanting; and the third factor was foliar spraying with nano-chitosan at three levels (0, 100, and 200 mg L⁻¹), applied four times during the experiment. The experiment was arranged in a randomized complete block design with three replications, and results were analyzed at a 5% probability level. The combined factors showed significant effects on the percentages of nitrogen, phosphorus, and potassium. The highest values were obtained under the treatment combination of irrigation every 4 days, soil application of tissue politer at 5 g, and foliar spraying with nano-chitosan at 200 mg L⁻¹, reaching (3.937, 1.197, and 2.263)% respectively. In contrast, the lowest values were recorded under irrigation every 8 days, with soil free of politer and spraying with distilled water only, reaching (3.003, 1.030, and 1.297)% respectively.