西瓜枯萎病生防细菌的筛选与生防机制研究

doi:10.16420/j.issn.0513-353x.2025-0286

摘要/Abstract

摘要：

西瓜枯萎病是重要的土传病害，严重影响西瓜的产量和品质。分离筛选具有西瓜枯萎病生防潜力的细菌并探究其作用机制极具意义。采用平板对峙法分离获得枯草芽孢杆菌（Bacillus subtilis）PJ3和深褐芽孢杆菌（Bacillus atrophaeus）HY5。发酵液处理结果表明，PJ3和HY5均可诱导病原菌分生孢子破裂，降低细胞膜中麦角甾醇和菌丝蛋白含量，破坏膜结构并提高通透性，抑制其生长。盆栽试验结果表明，与仅接种病原菌的对照相比，PJ3、HY5及其等量复配处理均可显著降低植株发病率和病情指数，且二者等量复配处理的病情指数降低了71.43%，显著优于单菌株处理。综上所述，PJ3和HY5菌株对西瓜枯萎病具有良好生防潜力，且复配使用效果最佳。

关键词: 西瓜, 枯萎病, 尖镰孢菌西瓜专化型, 枯草芽孢杆菌, 生物防治

Abstract:

Fusarium wilt of watermelon，caused by Fusarium oxysporum f. sp. niveum（FON），significantly reduces crop yield and quality. This study isolated two antagonistic bacteria. Bacillus subtilis PJ3 and Bacillus atrophaeus HY5，from soil using a dual-culture assay. Their fermentation broths disrupted FON conidia，damaged cell membranes by reducing ergosterol and protein content，and inhibited fungal growth. Pot trials confirmed their biocontrol efficacy，with PJ3，HY5，and their consortium significantly reducing disease incidence and severity. The consortium showed the best control，reducing disease severity by 71.43%，outperforming single strains. In summary，PJ3 and HY5 exhibit good biocontrol potential against watermelon Fusarium wilt，and their combined application yields the best results.

Key words: watermelon, Fusarium wilt, Fusarium oxysporum f. sp. niveum, Bacillus subtilis, biological control

杨嘉妮, 马乔女, 顾欣, 江彤, 苏小粉. 西瓜枯萎病生防细菌的筛选与生防机制研究[J]. 园艺学报, 2026, 53(5): 1521-1534.

YANG Jiani, MA Qiaonü, GU Xin, JIANG Tong, SU Xiaofen. Screening of Biocontrol Bacteria Against Fusarium Wilt in Watermelon and Study on Their Biocontrol Mechanisms[J]. Acta Horticulturae Sinica, 2026, 53(5): 1521-1534.

图/表 12

表1 不同生防细菌对FON的作用

Table 1 Effect of different biocontrol bacteria on FON

菌株 Strain	菌落直径/mm FON colony diameter	抑菌率/% Inhibition rate
对照Control	62.04 ± 0.19 a	—
PJ3	13.38 ± 2.19 h	78.40 ± 3.55 a
JB	14.86 ± 0.21 gh	76.03 ± 0.32 ab
XG2	15.59 ± 0.28 fgh	74.87 ± 0.48 abc
MX	21.03 ± 1.20 de	66.10 ± 1.94 de
SL1	19.11 ± 0.60 def	69.23 ± 0.97 cde
MD-1	20.85 ± 0.12 de	66.40 ± 0.17 de
XB-3	17.63 ± 3.04 fg	71.57 ± 4.91 cde
T1-4	22.45 ± 0.32 cd	63.83 ± 0.52 ef
PJ16	22.79 ± 0.20 cd	63.27 ± 0.32 ef
J4-2	25.16 ± 0.24 bc	59.47 ± 0.38 fg
TYC-4	28.72 ± 1.10 b	53.70 ± 1.79 g

图1 PJ3菌株菌落形态（A）、革兰氏染色（B）和芽孢染色（C）

Fig. 1 Colony morphology of strain PJ3（A），gram staining（B）and spore staining（C）

图2 PJ3和HY5菌株间的拮抗性

Fig. 2 Results of crossed culture of strain PJ3 and HY5

表2 菌株复配对FON的抑菌率

Table 2 Inhibition rate of compound bacterial inoculum on FON

菌株 Strain	FON菌落直径/mm FON diameter	抑菌率/% Inhibition rate
对照Control	52.74 ± 0.37 a	/
PJ3/HY5	10.56 ± 0.61 d	79.90 ± 1.15 a
PJ3	15.56 ± 0.56 c	70.37 ± 1.06 b
HY5	18.36 ± 1.24 b	65.05 ± 2.35 b

图3 PJ3与HY5菌株单独使用和复配对FON的抑菌效果

Fig. 3 Fungistasis effect of strain PJ3 and HY5 on FON

图4 显微观察不同发酵液对西瓜枯萎病菌FON的孢子萌发的影响

Fig. 4 Microscopic observation on the spore germination of FON treated with different fermentation broths

图5 不同菌株发酵液处理对西瓜枯萎病菌（FON）菌丝细胞膜渗透性的影响 t检验，*表示在P < 0.05水平上差异显著，**表示在P < 0.01水平上差异显著，ns表示差异不显著。下同

Fig. 5 Effect of crude extract of biocontrol bacterial inhibitory substance on permeability of FON mycelium cell membrane t-Test，* indicates significantly difference at P < 0.05 level，** indicates significantly difference at P < 0.01 level，ns indicates no significant difference. The same blow

图6 不同发酵液处理对西瓜枯萎病菌（FON）中麦角甾醇合成的抑制作用

Fig. 6 Inhibitory effect of different fermentation broth treatments on ergosterol synthesis in watermelon Fusarium wilt pathogen（FON）

图7 生防细菌抑菌蛋白粗提液对FON菌丝和培养液中MDA含量的影响 JMDA：菌丝体中，PMDA：培养液中，JMDA + PMDA：总含量

Fig. 7 Effect of crude extract of biocontrol bacterial bacteriostatic protein on MDA content of FON hyphae and culture medium JMDA：In mycelium，PMDA：In the culture medium，JMDA + PMDA：The total content

图8 生防菌株抑菌蛋白粗提液对FON菌丝内可溶性蛋白质含量的影响

Fig. 8 The effect of crude extract of antibacterial protein from biocontrol bacterial strains on the soluble protein content in FON mycelium

表3 不同发酵液处理对盆栽西瓜枯萎病的防治效果

Table 3 Control effect of different fermentation broth treatments on potted watermelon Fusarium wilt

处理 Treatments	发病率/% Disease incidence	病情指数 Disease index	防治效果/% Control efficiency
不接种FON（No FON vaccination）	73.33 ± 3.34 b	56.00 ± 1.47 b	—
FON（对照Control）	100.00 ± 0.00 a	90.67 ± 4.35 a	—
PJ3	40.00 ± 2.44 c	25.00 ± 1.33 d	72.42 ± 2.44 a
HY5	33.33 ± 3.12 d	22.67 ± 1.54 c	75.00 ± 2.87 b
PJ3/HY5	26.67 ± 1.24 e	15.00 ± 1.32 d	83.46 ± 3.48 c

表4 生防菌处理后西瓜枯萎病菌（FON）在根际土壤和幼苗根内的定殖量

Table 4 Colonization amount of watermelon Fusarium wilt pathogen（FON）in rhizosphere soil and seedling roots after biocontrol bacteria treatment ng · g-1

处理 Treatment	根际土壤 The soil of melon seedling roots		瓜苗根内 The roots of melon seedlings
处理 Treatment	10 d	30 d	10 d	30 d
不接种FON（No FON vaccination）	19.29 ± 1.57 b	27.77 ± 0.97 b	18.38 ± 0.30 b	25.19 ± 1.10 b
FON（对照Control）	23.67 ± 0.48 a	31.27 ± 0.63 a	22.96 ± 0.51 a	28.21 ± 1.46 a
PJ3	10.83 ± 0.92 cd	3.28 ± 0.40 c	11.16 ± 0.50 c	2.40 ± 0.51 c
HY5	11.13 ± 0.39 c	3.32 ± 0.99 c	11.36 ± 0.32 c	2.88 ± 0.28 c
PJ3/HY5	8.29 ± 0.84 d	2.37 ± 0.25 c	10.88 ± 0.53 c	1.48 ± 0.33 c

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