Antibacterial Functions and Proposed Modes of Action of Novel 1,2,3,4-Tetrahydro-β-carboline Derivatives that Possess an Attractive 1,3-Diaminopropan-2-ol Pattern against Rice Bacterial Blight, Kiwifruit Bacterial Canker, and Citrus Bacterial Canker

Abstract

In recent years, naturally occurring tetrahydro-β-carboline (THC) alkaloids and their derivatives have been of biological interest. However, few studies and developments have reported the use of such structures in managing plant bacterial diseases. Herein, an array of novel THC derivatives containing an attractive 1,3-diaminopropan-2-ol pattern were prepared to evaluate the antiphytopathogen activity in vitro and in vivo and explore innovative antibacterial frameworks. Notably, target compounds exhibited excellent activities against three rebellious phytopathogens, namely, Pseudomonas syringae pv. actinidiae (Psa), Xanthomonas axonopodis pv. citri, and Xanthomonas oryzae pv. oryzae, at related optimal EC 50 values of 2.39 (II 9 ), 2.06 (I 23 ), and 1.69 (II 9 ) μg/mL, respectively. These effects were superior to those of the parent structure 1,2,3,4-THC and positive controls. In vivo assays showed that II 9 exhibited excellent control efficiencies of 51.89 and 65.45% at 200 μg/mL against rice bacterial blight and kiwifruit bacterial canker, respectively, and I 23 substantially relieved the citrus canker on the leaves. Antibacterial mechanisms indicated that these THC compounds could induce the increment of reactive oxygen species and subsequently endow the tested bacteria with distinct apoptotic behavior. In addition, II 9 could alleviate the hypersensitive response and pathogenicity of Psa. Overall, these simple THC derivatives can be further developed as versatile antibacterial agents.

Synthesis and Biological Evaluation of 1,2,4-Triazole Thioethers as Both Potential Virulence Factor Inhibitors against Plant Bacterial Diseases and Agricultural Antiviral Agents against Tobacco Mosaic Virus Infections

“…The pathogenicity assay was performed by inoculating the premixed Xoo cells (OD 595 = 0.6) with the corresponding compound A 10 (25.05 μg/mL) or an equivalent DMSO solution on the adult rice plants through a leaf-cutting method. After the rice plants were cultured for 14 days in a greenhouse, the lesion lengths were measured and photographed. , …”

“…After the rice plants were cultured for 14 days in a greenhouse, the lesion lengths were measured and photographed. 18,65 2.5. RNA Extraction and qRT-PCR Analysis.…”

Transcriptome Analysis on the Mechanism of Ethylicin Inhibiting Pseudomonas syringae pv. actinidiae on Kiwifruit

“…In vivo tests of ethylicin's efficacy on bacterial canker disease of the one-year-old kiwifruit plant was determined following the method of Liu [25]. The kiwifruit plant branch was cut 1 mm open with a sterilized knife and then injected with 10µL of ethylicin solution at a concentration of 0, 200, and 500 µg/mL.…”

Sustainable Management of Diseases in Horticulture: Conventional and New Options

“…The role of phosphorus in crop protection appears to be inconsistent and unpredictable. Relatively high potassium content generally has positive effects in reducing disease severity [202]. In particular, potassium phosphate was found to significantly reduce the severity of barley powdery mildew [206].…”

“…oryzae, the causal agent of rice bacterial blight; Pseudomonas syringae pv. actinidiae, the causal agent of kiwifruit bacterial canker [202].…”