橡胶树热激蛋白HbHSP90.1抗橡胶树白粉病菌的功能研究OA

[Objective]Rubber tree powdery mildew severely constrains natural rubber production.Identify-ing disease resistance factors and elucidating their functions are of great significance for green control.Heat shock protein HSP90 is a key regulator of plant immunity,and its member HbHSP90.1 has been confirmed to be induced by powdery mildew infection.Therefore,this study aimed to reveal the specific function of HbHSP90.1 in rubber tree response to powdery mildew infection,to clarify its regulatory role in disease resistance.[Method]HSP90 activity was interfered with using an inhibitor,or HbHSP90.1 gene was silenced by dsRNA,followed by rubber tree powdery mildew inoculation to assess disease resistance.Rubber trees were treated with plant hormone ana-logs that induce resistance(sodium salicylate and ethephon),and HbHSP90.1 expression was measured by reverse transcription quantitative PCR.After silencing HbHSP90.1,the contents of salicylic acid and the ethylene precur-sor 1-aminocyclopropane-1-carboxylic acid(ACC)were determined.[Result]Inhibiting the activity of HbHSP90.1 or silencing the gene significantly increased the susceptibility of rubber trees to powdery mildew.Ex-pression analysis showed that HbHSP90.1 was continuously upregulated under sodium salicylate treatment,but it was suppressed under ethephon treatment.After silencing HbHSP90.1 and inoculating with powdery mildew,the endogenous salicylic acid content in the leaves decreased significantly,while ACC content increased significantly.This indicated that the gene may participate in regulating immune responses by modulating hormone balance.[Conclusion]HbHSP90.1 is a key positive regulator in the rubber tree's response to powdery mildew infection.It participates in regulating the plant's immune response to powdery mildew by positively regulating the salicylic acid signaling pathway.This study provides new experimental evidence for in-depth analysis of the molecular mechanism of disease resistance in rubber trees.