烤烟黑胫病抗性评价及生理响应特性分析

Resistance Analysis of Tobacco Black Shank Disease and Characteristic of Physiological Response

本研究旨在揭示不同烤烟品种对烟草黑胫病的抗性机理。通过对抗病性的鉴定,从24个烤烟品种(系)中鉴定出4个高抗品种、8个中抗品种、8个中感品种和4个高感品种。对这些品种在烟草疫霉(Phytophthora parasitica var.nicotianae)侵染后,从中选取2个高抗品种和2个高感品种测定其抗氧化酶系活性、水杨酸含量以及抗病相关基因的表达情况。结果表明,在受到病原菌侵染时,高抗品种的抗氧化酶活性显著高于高感品种,暗示着更强的氧化应激防御能力。此外,高抗品种中的内源水杨酸合成以及抗病相关基因的诱导表达均显著高于高感品种,表明这些品种能够更有效地激活其防御系统以应对烟草黑胫病菌的侵染。本研究结果为理解烤烟对黑胫病的抗性机制提供了重要信息,并为烟草抗病育种提供了理论依据。

The study aimed to elucidate the resistance mechanisms of different tobacco varieties against tobacco black shank disease.The identification of resistance to tobacco black shank disease of 24 tobacco varieties(lines)was conducted,and four highly resistant varieties,eight moderately resistant varieties,eight moderately susceptible varieties,and four highly susceptible varieties were identified.Two highly resistant varieties and two highly susceptible varieties were selected to determine the activity of antioxidant enzyme system,salicylic acid content,and expression of disease-related genes after Phytophthora parasitica var.nicotianae infection.The results revealed that the antioxidant enzyme activity in highly resistant varieties was significantly higher than that in highly susceptible varieties after infection with P.nicotianae,suggesting that highly resistant varieties have stronger antioxidative capabilities.Additionally,the synthesis of endogenous salicylic acid in high-resistant varieties was significantly stronger than that in highly susceptible varieties after infection with P.nicotianae,and the expression of disease resistance genes was also significantly higher than that in highly susceptible varieties,indicating that resistant varieties can more efficiently trigger their own defense system to resist the invasion of P.nicotianae.The study offers insights into the mechanisms of tobacco against tobacco black shank disease and provides a theoretical foundation for breeding disease-resistant tobacco varieties.