The Control of Fusarium Root Rot and Development of Coastal Pine (Pinus thunbergii Parl.) Seedlings in a Container Nursery by Use of Bacillus licheniformis MH48

Abstract

This study investigated the control of Fusarium root rot and development of coastal pine (Pinus thunbergii) seedlings in a container nursery by using Bacillus licheniformis MH48. High-quality seedlings without infectious diseases cause vigorous growth. Fusarium root rot caused by Fusarium oxysporum is responsible for serious damage to coastal pine seedlings in nurseries. B. licheniformis MH48 produced enzymes that degraded the fungal cell walls, such as chitinase and β-1,3-glucanase. These lytic enzymes exhibited destructive activity toward F. oxysporum hyphae, which were found to play key roles in the suppression of root rot. In addition, B. licheniformis MH48 increased the nitrogen and phosphorus in soils via fixed atmospheric nitrogen and solubilized inorganic phosphate. B. licheniformis MH48 produced the phytohormone auxin, which stimulated seedling root development, resulting in increased nutrient uptake in seedlings. Both the bacterial inoculation and the chemical fertilizer treatments significantly increased seedling growth and biomass, and the bacterial inoculation had a greater effect on seedling development. Based on the results from this study, B. licheniformis MH48 showed potential as a biological agent against Fusarium root rot and as a promoter of growth and development of Pinus thunbergii seedlings.

Control of Fungal Diseases and Increase in Yields of a Cultivated Jujube Fruit (Zizyphus jujuba Miller var. inermis Rehder) Orchard by Employing Lysobacter antibioticus HS124

“…Cell wall-degrading enzymes such as chitinase produced by antagonistic bacteria are known to play key roles in the suppression of phytopathogenic fungi [25][26][27][28][29][30]. In the present study, results of quantitative chitinase assay indicated that strain HS124 produced high levels of chitinase in colloidal containing medium (Figure 3).…”

“…The experiment was repeated three times with three replications. The inhibition of fungal growth by the HS124 strain was determined with the following formula: inhibition (%) = [(α − β)/α] × 100, where α was the radial growth of phytopathogenic fungus on the control plate and β was the radial growth of phytopathogenic fungus on the dual culture plate [27,28,30].…”

“…Among various other eco-friendly cultivation methods, environmentally friendly cultivation methods that employ biological control by using microorganisms can promote crop production. Thus, they are gaining popularity because of their high potential value [25][26][27][28]. Plant growth promoting rhizobacteria (PGPR) play a significant role in reduction of infection by plant pathogenic fungi leading to be a promising alternative to control plant diseases.…”

“…Plant growth promoting rhizobacteria (PGPR) play a significant role in reduction of infection by plant pathogenic fungi leading to be a promising alternative to control plant diseases. PGPR are known to produce lytic enzymes, preventing infection by fungal diseases [27][28][29][30]. However, the biocontrol efficacy of PGPR on diseases associated with jujube fruit is not clearly investigated.…”

“…PGPR provide plants with phytohormones [24,31], especially auxin, which can loosen the cell wall of root tissue cells, allowing cells to absorb additional nutrients, thereby promoting the growth of root hair and lateral roots [24,25,27,28,31,32]. In addition, auxin helps establish symbiosis with rhizobia or mycorrhiza and facilitates the uptake of nutrients from soils, promoting plant production [24,25,27,28,31,32]. In particular, after the flower is fertilized, auxin acts on the division and expansion of cells, promoting vegetative growth and increasing fruit size and yield [31,33,34].…”