中国农业科学 ›› 2025, Vol. 58 ›› Issue (11): 2145-2161.doi: 10.3864/j.issn.0578-1752.2025.11.006

• 植物保护 • 上一篇    下一篇

钙调节活性氧和内生细菌增强水稻对纹枯病抗性

赵守帅(), 都梦翔, 郭思宇, 张烁, 赵宏伟, 赵长江()   

  1. 黑龙江八一农垦大学农学院/农业农村部东北平原农业绿色低碳重点实验室,黑龙江大庆 163319
  • 收稿日期:2025-01-15 接受日期:2025-02-22 出版日期:2025-06-01 发布日期:2025-06-09
  • 通信作者:
    赵长江,E-mail:
  • 联系方式: 赵守帅,E-mail:2753638862@qq.com。
  • 基金资助:
    国家自然科学基金(31101429); 黑龙江省“双一流”学科协同创新成果建设(LJGXCG2022-107); 黑龙江八一农垦大学青年创新人才项目(CXRC2016-02)

Calcium Regulates Reactive Oxygen Species and Endophytic Bacteria to Enhance Rice Resistance to Sheath Blight

ZHAO ShouShuai(), DU MengXiang, GUO SiYu, ZHANG Shuo, ZHAO HongWei, ZHAO ChangJiang()   

  1. College of Agronomy, Heilongjiang Bayi Agricultural University/Key Laboratory of Low-Carbon Green Agriculture in Northeastern China, Ministry of Agriculture and Rural Affairs, Daqing 163319, Heilongjiang
  • Received:2025-01-15 Accepted:2025-02-22 Published:2025-06-01 Online:2025-06-09

摘要:

【背景】 由立枯丝核菌(Rhizoctonia solani)引起的水稻纹枯病在世界各稻区常年普遍发生,因抗性品种严重缺乏,给水稻绿色生态种植带来巨大挑战。【目的】 揭示外源钙调物处理对水稻抗病的调节作用及其调控机制。【方法】 四叶一心期籼稻和粳稻幼苗喷施5 mmol·L-1钙调物150 mL,共喷施两次,每24 h喷施一次,在首次喷施48 h后采用牙签嵌入法在水稻第2、3叶片叶鞘接种立枯丝核菌,取同一部位叶片进行活性氧相关指标、光合色素含量测定及内生细菌分析。【结果】 加钙(CaCl2和Ca(NO3)2)处理增强供试水稻的抗病性,减钙(螯合剂EGTA)处理削弱水稻的抗病性。对各处理水稻植株钙含量分析发现,与空白对照相比,加钙处理提升植株钙含量,减钙处理降低植株钙含量;病原菌接种导致体内钙含量较相应对照处理均降低。加钙处理使水稻幼苗活性氧( 和H2O2)含量增加,减钙处理引起的活性氧含量变化比加钙处理明显。加钙处理后,水稻活性氧含量变化与病斑面积变化趋势一致,二者正相关;SOD、POD、CAT、APX、GPX活性和GSH含量保持相对较高的水平,其中CAT活性增幅尤为明显。减钙处理多数情况下相关酶活性显著降低。加钙处理可重构水稻体内活性氧稳态,包括活性氧产生、抗氧化系统和膜损伤指标。与接种对照相比,加钙处理水稻病斑面积与H2O2含量正相关性增强,CAT负相关性增强、ASA负相关性增强、APX负相关性减弱、GSH由负相关转为正相关,MDA正相关性减弱、电导率由负相关转为正相关。加钙处理使接菌水稻叶片内生细菌群落微生物丰富度降低、内生细菌群落多样性有限增加。尽管加钙处理对水稻内生细菌共现网络影响有限,但立枯丝核菌接种对水稻内生细菌网络产生显著影响,且加钙处理内生菌网络鲁棒性在接菌前后均显著高于空白组和减钙组,接菌后网络易损性显著低于空白组和减钙组。【结论】 加钙处理可以显著降低供试水稻相对病斑面积,提高水稻SOD、POD、CAT活性和GSH含量,减少体内活性氧积累,减少膜损伤,维持活性氧稳态提高水稻抗病性;同时,钙处理降低水稻内生细菌群落丰富度、增加其多样性,提高有益菌属占比,重构稳定性增强的内生细菌抗病群落。

关键词: 钙, 水稻, 纹枯病, 立枯丝核菌, 活性氧, 内生细菌

Abstract:

【Background】 Rice sheath blight, caused by Rhizoctonia solani, is a prevalent disease in rice-growing regions worldwide, posing significant challenges to the green ecological cultivation of rice due to the severe lack of resistant varieties.【Objective】 To elucidate the regulatory effect of exogenous calcium treatment on rice disease resistance and its regulatory mechanism.【Method】 Four-leaf stage indica and japonica rice seedlings were sprayed with a 5 mmol·L-1 calcium regulator at 150 mL and sprayed twice at a 24 h interval. The toothpick insertion method was used to inoculate R. solani in the second- and third-leaf sheaths of rice 48 h after the first spray. Leaves from the same part were taken for determination of reactive oxygen species (ROS)-related indicators, photosynthetic pigment content, and endophytic bacterial analysis.【Result】 Calcium addition treatment (CaCl2 and Ca(NO3)2) enhanced the resistance of the tested rice against R. solani while the chelating agent EGTA treatment weakened their resistance. Compared with the blank control, the calcium content of plants was increased with calcium addition treatment and decreased with calcium reduction treatment; pathogen inoculation resulted in lower calcium content in the plants compared to the corresponding control treatments. All calcium addition treatments caused an increase in the content of and H2O2 in rice seedlings, the change of ROS content caused by the calcium reduction treatment was more obvious than that of calcium addition treatment. Calcium addition treatment caused changes in rice ROS content consistent with the trend of lesion area changes, with a positive correlation between the two. Calcium addition treatment also maintained the enzyme activities of SOD, POD, CAT, APX, GPX and content of GSH at relatively high levels. The increase in CAT activity was particularly significant. In most cases, calcium reduction treatment significantly reduced the activity of related enzymes. Calcium addition treatment could reconstruct rice’s ROS homeostasis and enhance disease resistance and immune responses, including ROS production, antioxidant systems, and membrane damage indicators. Compared with the blank control, the positive correlation between the lesion area and H2O2 content in rice treated with calcium addition was enhanced, the negative correlation with CAT was enhanced, the negative correlation with ASA was enhanced, the negative correlation with APX was weakened, the correlation with GSH turned from the negative to positive, the positive correlation with MDA was weakened, and the correlation with conductivity turned from negative to positive. Calcium addition treatment reduced the microbial richness of endophytic bacterial community in inoculated rice leaves and limitedly increased the diversity of endophytic bacterial community. Although calcium addition treatment had a limited impact on the endophytic bacterial co-occurrence network in rice, the inoculation of R. solani significantly affected the endophytic bacterial network in rice. Furthermore, the network robustness after calcium addition treatment was significantly higher than that of the control group and the calcium reduction treatment group, both before and after inoculation; the network vulnerability after inoculation was significantly lower than that of the control group and the calcium reduction treatment group.【Conclusion】 Calcium addition treatment can significantly reduce the relative lesion area of tested rice, enhance the activities of SOD, POD, CAT and content of GSH, decrease the accumulation of ROS, reduce membrane damage, maintain the homeostasis of ROS and enhance the disease resistance of rice; simultaneously, calcium addition treatment reduces the richness of endophytic bacterial community, increases its diversity, enhances the proportion of beneficial bacterial genera, restructures the endophytic bacterial community with enhanced stability.

Key words: calcium, rice, sheath blight, Rhizoctonia solani, reactive oxygen species (ROS), endophytic bacteria