Essential oils in the control of Botrytis cinera: influence on post harvest quality of Rubi grapes

Abstract Agrochemicals are used to control diseases in post-harvest grapes, but although efficient, they may cause human health problems. Thus, the objective of the present work was to verify the potential of the volatile compounds present in the essential oils of the fruits pitanga (EOP), guaçatonga (EOG) and melaleuca (EOM) in the control of Botrytis cinerea both in vitro and inoculated in ' Rubi ' grapes, as well as to verify the induction of resistance in these fruits. Thus, B. cinerea mycelial growth, grey mould control in 'Rubi' grapes, post-harvest quality of the grapes and the activities of the enzymes polyphenoloxidase (PPO), phenylalanine ammonium lyase (PAL), glucanase (GLU) and chitinase, were evaluated. According to the results it was observed that the volatile compounds released by the essential oils reduced the rates of mycelial growth of B. cinerea and of the grey mould disease, and the treatments with the volatiles from EOP and EOG activated the resistance induction mechanisms of these fruits. Thus, EOP and OEG release compounds that can act directly on B. cinerea and also induce resistance in the 'Rubi' grapes, reducing the grey mould in these grapes.

摘要：农用化学品常用于防控采后葡萄病害，尽管其防控效果显著，但可能引发人体健康风险。为此，本研究旨在验证毕当加（pitanga）果实精油（EOP）、圭查通加（guaçatonga）精油（EOG）以及白千层（melaleuca）精油（EOM）中的挥发性成分，在体外及接种灰葡萄孢（Botrytis cinerea）的‘鲁比’（'Rubi'）葡萄上的抑菌潜力，同时验证该类成分对果实的抗病诱导效果。本研究评估了灰葡萄孢菌丝生长情况、‘鲁比’葡萄灰霉病防控效果、葡萄采后品质，以及多酚氧化酶（polyphenoloxidase, PPO）、苯丙氨酸解氨酶（phenylalanine ammonium lyase, PAL）、葡聚糖酶（glucanase, GLU）和几丁质酶（chitinase）的活性。结果表明，三种精油释放的挥发性成分可显著抑制灰葡萄孢菌丝生长速率并降低灰霉病病害发生率；其中EOP与EOG的挥发性处理可激活果实的抗病诱导机制。综上，EOP与EOG释放的活性成分既可直接抑制灰葡萄孢，又可诱导‘鲁比’葡萄产生抗病性，从而降低果实灰霉病的发生。