College of Plant Protection, Jilin Agricultural University, Changchun 130118, PR China.
College of Plant Sciences, Jilin University, Changchun 130062, PR China.
Sci Total Environ. 2024 Apr 1;919:170771. doi: 10.1016/j.scitotenv.2024.170771. Epub 2024 Feb 7.
Tomato gray mold, caused by Botrytis cinerea, is an important disease in tomato. Pantoea jilinensis D25, isolated form tomato rhizosphere soil, can prevent B. cinerea infection in tomato. To determine the underlying biocontrol mechanism, the transcriptome of P. jilinensis D25 was assessed. Differential expression analysis revealed that 941 genes were upregulated and 997 genes were downregulated. Through transcriptome analysis, the suhB gene was knocked out. ΔPj-suhB exhibited lower swimming motility and colonization abilities than strain D25. After 4 days of co-cultivation, ΔPj-suhB could reduce the colony diameter, mycelial weight, and spore production of B. cinerea with the inhibitory rates of 31.72 %, 39.62 %, and 47.42 %, respectively, compared with control. However, the inhibitory rates of strain D25 were 52.91 %, 60.09 %, and 76.85 %, respectively, compared with control. Strain D25 could significantly downregulate pathogenesis-related genes in B. cinerea, whereas the expression level of these genes in B. cinerea was higher after treatment with ΔPj-suhB than after that with strain D25. In vitro experiments revealed that the lesion area and disease control efficacy were 1.520 and 0.038 cm and 68.7 % and 99.0 %, respectively, after ΔPj-suhB and strain D25 treatments. Pot experiments revealed that ΔPj-suhB and strain D25 could prevent tomato plants from B. cinerea infection with the disease reduction rate of 37.5 % and 75.0 %, respectively. Though the activities of defense-related enzymes and expression level of defense related genes in tomato plants were increased under ΔPj-suhB treatment, these effects were higher after strain D25 treatment. Thus, these results demonstrated that suhB was the key gene in strain D25 underlying its biocontrol effect and mobility.
番茄灰霉病由灰葡萄孢引起，是番茄的重要病害。从番茄根际土壤中分离得到的泛菌吉林亚种 D25 可以预防番茄灰霉病。为了确定潜在的生防机制，评估了 P.吉林亚种 D25 的转录组。差异表达分析显示，941 个基因上调，997 个基因下调。通过转录组分析，敲除了 suhB 基因。与菌株 D25 相比，ΔPj-suhB 的游动能力和定殖能力较低。经过 4 天共培养，ΔPj-suhB 对 B. cinerea 的菌落直径、菌丝干重和孢子产量的抑制率分别为 31.72%、39.62%和 47.42%，而对照的抑制率分别为 52.91%、60.09%和 76.85%。与对照相比，D25 菌株可显著下调 B. cinerea 中的病程相关基因，而与 D25 菌株处理相比，B. cinerea 中这些基因的表达水平更高。体外实验表明，ΔPj-suhB 和 D25 菌株处理后，病变面积和防治效果分别为 1.520 和 0.038cm 和 68.7%和 99.0%。盆栽试验表明，ΔPj-suhB 和 D25 菌株处理可使番茄植株分别降低 37.5%和 75.0%的发病率。尽管 ΔPj-suhB 处理可提高番茄植株防御相关酶的活性和防御相关基因的表达水平，但 D25 菌株处理的效果更高。因此，这些结果表明 suhB 是菌株 D25 发挥生防作用和运动性的关键基因。
