辣椒疫霉是一种具有广泛寄主范围的高度破坏性的植物病原卵菌,并造成巨大的损失。大黄因子L3(EFL3)是一种天然的植物衍生化合物,已在医学和化妆品应用中得到广泛研究。在这项研究中,测定了105株辣椒芽孢杆菌对EFL3的敏感性,研究了EFL3抗辣椒的生物学活性和生理效应。EFL3抑制菌丝体生长和孢子萌发的中值有效浓度(EC50)值范围为0.66至8.94μg/mL(平均值,2.96±0.91μg/mL)和1.63至13.16μg/mL(平均值,5.30±1.64μg/mL),分别。EFL3处理导致辣椒芽孢杆菌细胞壁和细胞膜损伤,通过形态学和超微结构观察揭示了这一点,碘化丙啶(PI)和钙氟白色(CFW)染色,并测量相对电导率以及丙二醛(MDA)和甘油含量。此外,磷脂和纤维素的含量,它们是细胞膜和细胞壁的主要组成部分,在EFL3治疗后显著降低。此外,EFL3在体内分离的番茄叶片和辣椒幼苗上对辣椒的保护和治疗效果。这些数据表明,EFL3对辣椒假单胞菌表现出强抑制活性,从而表明它可能是控制辣椒假单胞菌诱导的疾病的有效替代方案。
Phytophthora capsici is a highly destructive phytopathogenic oomycete with a broad host range and is responsible for tremendous losses. Euphorbia factor L3 (EFL3) is a natural plant-derived compound that has been widely studied in medicine and cosmetic applications. In this study, the sensitivity of 105 P. capsici isolates to EFL3 was determined, and the biological activity and physiological effects of EFL3 against P. capsici were investigated. The median effective concentration (EC50) values for EFL3 inhibition mycelial growth and spore germination ranged from 0.66 to 8.94 μg/mL (mean, 2.96 ± 0.91 μg/mL) and 1.63 to 13.16 μg/mL (mean, 5.30 ± 1.64 μg/mL), respectively. EFL3 treatment resulted in cell wall and cell membrane damage of P. capsici, which was revealed by morphological and ultrastructural observations, propidium iodide (PI) and calcofluor white (CFW) staining, and measurements of relative conductivity as well as malondialdehyde (MDA) and glycerol contents. In addition, the contents of phospholipid and cellulose, which are the major components of cell membrane and cell wall, were significantly reduced following EFL3 treatment. Furthermore, EFL3 provided protective as well as curative efficacies against P. capsici on detached tomato leaves and pepper seedlings in vivo. These data show that EFL3 exhibits strong inhibitory activity against P. capsici, thereby suggesting that it could be an effective alternative for controlling P. capsici-induced diseases.