Cork oak (Quercus suber) is one of the most important forest species in Portugal and in the Mediterranean basin, but in recent decades a progressive decline has been registered in the montado ecosystem. The main phytopathogenic agent involved in this process, Phytophthora cinnamomi, has a high infection potential and survival ability, and became a serious threat to this ecosystem. Extensive areas of cork oak are infected in Portugal, being imperative to find new ways to control this disease. The complex lifecycle of this pathogen and the small number of effective agrochemicals currently authorized against Phytophthora spp., with phosphonates taking advantage, justifies this work where new products with antagonism against Oomycetes or biostimulant properties were tested. This study aimed to evaluate the efficacy of BLAD (a polypeptide with antifungal, anti-oomycete and biostimulant properties), potassium phosphonate and salicylic acid in Q. suber infected with P. cinnamomi, quantifying the severity of root lesions. BLAD, potassium phosphonate and salicylic acid treatments showed lower root lesion severities than the inoculated control, and proved to be effective as they provided a slower disease evolution. The lowest lesion severity in cork oak roots observed with BLAD treatments allowed us to consider BLAD as the most promising product among the three we tested.

栓皮栎 ( Quercus suber ) 是葡萄牙和地中海盆地最重要的森林树种之一，但近几十年来，蒙塔多生态系统的数量逐渐减少。参与这一过程的主要植物病原菌肉桂疫霉(Phytophthora cinnamomi)具有很高的感染潜力和生存能力，成为对该生态系统的严重威胁。葡萄牙大面积的软木橡树受到感染，迫切需要找到控制这种疾病的新方法。这种病原体的复杂生命周期和目前授权用于对抗疫霉属的有效农用化学品数量较少，并利用膦酸盐，证明了这项工作的合理性，即测试了具有拮抗卵菌或生物刺激特性的新产品。本研究旨在评估 BLAD（一种具有抗真菌、抗卵菌和生物刺激特性的多肽）、磷酸钾和水杨酸对感染肉桂霉的Q. suber的功效，量化根部病变的严重程度。BLAD、磷酸钾和水杨酸处理显示出比接种对照更低的根部病变严重程度，并且被证明是有效的，因为它们提供了更慢的疾病进展。通过 BLAD 处理观察到的软木橡树根部病变严重程度最低，这使我们可以将 BLAD 视为我们测试的三种产品中最有前途的产品。