醋糟生物质炭对尖孢镰刀菌胁迫下番茄系统抗性的影响

为探明生物质炭介导的系统抗性在土传病害防治过程中的作用,以番茄枯萎病为对象,采用盆栽试验,研究尖孢镰刀菌胁迫下生物质炭对番茄体内抗氧化酶活性和非酶类抗氧化分子含量的变化,及对相关抗性基因表达的影响。结果表明:施加生物质炭可显著降低番茄的病害程度。在尖孢镰刀菌胁迫下,番茄叶片光合色素显著降低,丙二醛含量显著增加,生物质炭的施加可显著降低尖孢镰刀菌胁迫造成的光合色素和丙二醛含量变化。施加生物质炭在降低番茄体内过氧化物酶活性的同时,可提高“解毒酶”(包括过氧化氢酶、超氧化物歧化酶、谷胱甘肽还原酶和谷胱甘肽S-转移酶)的活性。在尖孢镰刀菌胁迫下,番茄体内氧化型谷胱甘肽含量明显升高,生物质炭的施加(3%)在显著降低氧化型谷胱甘肽含量的同时,显著提高了还原型谷胱甘肽含量,表明生物质炭可通过提高抗氧化分子含量来加强番茄体内活性氧的清除效率。此外,在生物质炭的作用下,番茄水杨酸相关基因PR1a、MPK2和NPR1的表达下调,而茉莉酸相关基因DEF1、JAZ1、JAZ3和乙烯相关基因ACO1和ACS的表达上调。结果表明施加生物质炭可增强番茄系统防御尖孢镰刀菌入侵的启动效应和能力。

Vinegar residue biochar regulates the systemic resistance of tomato under Fusarium oxysporum stress

To explore the effects and possible mechanisms associated with biochar-elicited suppression of soil-borne diseases and improved plant performance, pot experiments were used to explore the ability of biochar to induce systemic resistance in tomato against Fusarium wilt caused by a soil-borne pathogen, Fusarium oxysporum f. sp. lycopersici Snyder and Hansen. Results showed that biochar application significantly reduced tomato disease severity. The photosynthetic pigments and malondialdehyde content of tomato leaves were significantly decreased and increased, respectively under F. oxysporum stress, and the application of biochar significantly reduced the changes in photosynthetic pigments and malondialdehyde content. The activity of peroxidase in tomato significantly reduced, whereas the activity of "detoxification enzymes"(including catalase, superoxide dismutase, glutathione reductase, and glutathione S-transferase) significantly increased during the biochar treatment. The content of oxidized glutathione in tomato was significantly increased under F. oxysporum stress. The application of biochar(3%) significantly reduced the content of oxidized glutathione but significantly increased the content of reduced glutathione, indicating that the biochar could enhance the removal efficiency of active oxygen in tomato. In addition, application of biochar could enhance the priming effect and ability of tomato system against F. oxysporum invasion, which is mainly dependent on the pathway mediated by jasmonic acid and ethylene. Specifically, with the treatment of biochar, the relative expression of salicylic acid-related genes(PR1a, MPK2, and NPR1) was down-regulated, while the relative expressions of jasmonic acid-related genes (DEF1, JAZ1, and JAZ3) and ethylene-related genes(ACO1 and ACS) were up-regulated. The above results indicate that the application of biochar can enhance the resistance ability of tomato system to defend against F. oxysporum stress.