Evaluation of the Efficiency of Ordinary and Nano-Chitosan in Stimulating Acquired Systemic Resistance of Cucumber Plants Against the Fungus Fusarium solani Which Causes Root Rot Disease

Abstract

Under laboratory and greenhouse conditions, the study aimed to use ordinary and nano-chitosan at doses of (0.5, 1.0, and 2.0)% to stimulate acquired systemic resistance and defensive responses in Cucumis sativus L. against the fungus Fusarium solani that causes cucumber root rot. In contrast to the control treatment, where the percentage of seed germination reached 100%, the findings of the pathogenicity assessment of the fungus F. solani revealed a considerable decrease in the percentage of germination of cabbage seeds, with the average percentage of germination reaching 0.00%. In order to evaluate the efficacy of ordinary and nano-chitosan against the fungus F. solani, which causes cucumber root rot, the results also revealed that these additions were made to the culture medium. Results indicated a direct correlation between the concentrations of chitosan addition and the percentage of fungal growth inhibition (F. solani). Fungal growth inhibition percentages reached 88.8% and 72.2%, respectively, when using 2% concentrations of nano- and ordinary chitosan, compared to 0.0% in the control treatment (fungus F. solani). The application of both ordinary and nano-chitosan, along with their combination, to plants infected with the pathogenic fungus under greenhouse conditions resulted in a noteworthy decrease in both the rate and severity of infection when compared to the control treatment. The infection rate was observed to be (48.00, 24.00, and 18.00)%, and the severity was (37.00, 12.66, and 10.00)% for both types of chitosan. Additionally, their interaction was evaluated in relation to the infection rate (100.00) and severity (90.00%), respectively. Additionally, spraying regular and nano chitosan, as well as their combination, increased the cucumber plant’s growth parameters. The intervention treatment outperformed the control treatment (mushrooms) in terms of plant height, fresh and dry weight of the shoot and root system, and plant height, achieving growth rates of 22.52 cm, 15.55, 3.00, 1.75, and 0.63 g, respectively. Results from lab and greenhouse experiments show that nano-chitosan performs noticeably better than regular chitosan. This suggests that nano-chitosan could be used first, and then ordinary chitosan, as an alternative to chemical pesticides in controlling the causes of cucumber root rot disease.