Cyanobacteria-Mediated Immune Responses in Pepper Plants against Fusarium Wilt

Abstract

Research in plant pathology has increasingly focused on developing environmentally friendly, effective strategies for controlling plant diseases. Cyanobacteria, including Desmonostoc muscorum, Anabaena oryzae, and Arthrospiraplatensis, were applied to Capsicum annuum L. to induce immunity against Fusarium wilt. Soil irrigation and foliar shoots (FS) application were used in this investigation. The disease symptoms, disease index, osmotic contents, total phenol, Malondialdehyde (MDA), hydrogen peroxide (H2O2), antioxidant enzymes (activity and isozymes), endogenous hormone content, and response to stimulation of defense resistance in infected plants were assessed. Results demonstrated that using all cyanobacterial aqueous extracts significantly reduced the risk of infection with Fusarium oxysporum. One of the most effective ways to combat the disease was through foliar spraying with Arthrospira platensis, Desmonostoc muscorum, and Anabaena oryzae (which provided 95, 90, and 69% protection percent, respectively). All metabolic resistance indices increased significantly following the application of the cyanobacterial aqueous extracts. Growth, metabolic characteristics, and phenols increased due to the application of cyanobacteria. Polyphenol oxidase (PPO) and peroxidase (POD) expressions improved in response to cyanobacteria application. Furthermore, treatment by cyanobacteria enhanced salicylic acid (SA) and Indole-3-Acetic Acid (IAA) in the infected plants while decreasing Abscisic acid (ABA). The infected pepper plant recovered from Fusarium wilt because cyanobacterial extract contained many biologically active compounds. The application of cyanobacteria through foliar spraying seems to be an effective approach to relieve the toxic influences of F. oxysporum on infected pepper plants as green and alternative therapeutic nutrients of chemical fungicides.

Biocontrol of early blight disease of eggplant using endophytic Aspergillus terreus: improving plant immunological, physiological and antifungal activities

“…Also, the frequent use of chemical pesticides has revealed many problems in plant, human, and animal health. It is now necessary for researchers to try to reach biological methods as safe alternatives to the use of chemical pesticides (Abdelaziz et al 2022a ; Attia et al 2016 ). Previous studies have proven that the use of plant growth-promoting microorganisms has a significant anti-microbial effect in addition to stimulating the plant’s physiological immunity, which is beneficial to increasing productivity (Attia et al 2022a , 2022b ; Abd Alhakim et al 2022 ).…”

Endophytic fungi Aspergillus spp. reduce fusarial wilt disease severity, enhance growth, metabolism and stimulate the plant defense system in pepper plants

“…Under fungal infection, plants accumulate osmolytes such as proline that act as osmoregulator to scavenge reactive oxygen species [78]. The increase of proline contents in infected pepper plants was similarly to that in heavy studies [21,79]. In addition, stressed plants treated with fungal endophytes (such as Piriformospora indica and Aspergillus ochraceus) have low levels of proline in comparison with non-treated plants [80].…”

“…Plant physiological immunity can be stimulated by many means, perhaps the most important of which are growth-stimulating organisms against stress [3,18,19]. The harmful effect of Fusarium wilt can be minimized by the induction of natural exogenous inducers such as phytohormones and antioxidant molecules [20][21][22]. Furthermore, the molecules extracted from endophytes have been reported to be powerful biostimulants of growth, physiological immunity, and yield, as they enhanced tolerance to environmental stress by stimulating the antioxidant system and improving nutrient availability and nutrient uptake from the soil [23][24][25][26].…”

Mycosynthesis of Silica Nanoparticles Using Aspergillus niger: Control of Alternaria solani Causing Early Blight Disease, Induction of Innate Immunity and Reducing of Oxidative Stress in Eggplant

“…Heavily recently studies demonstrated that fungal plant diseases caused significant changes in vegetative growth [ 82 , 83 , 84 ]. Results in Figure 6 shows A. solani affected greatly reduced eggplant growth traits; shoot length, root length and number of leaves by 50.96%, 48.27% and 34.89%.…”