植物源LsGRP1具防禦預警與田間應用潛力

Abstract

隨著氣候環境不斷變化與糧食需求上升，農業面臨更嚴重的病害威脅與產量挑戰，故需在現行農法中導入病蟲害整合管理(integrated pest management)與植物健康管理(plant health management)措施，以提升病害防治與生產效率，並降低對環境造成之影響。本研究探討百合蛋白LsGRP1系統性調控植物預警效應(priming effect)的主效區段與對應之植物受體，以及其應用於田間植物健康管理之潛力。觀察融合蛋白SUMO-LsGRP1∆SS根部預處理後的阿拉伯芥幼苗與番茄植株經flg22誘導所產生的防禦反應，確認LsGRP1可系統性啟動植物的預警效應，而觀察經SUMO-LsGRP1∆SS澆灌的阿拉伯芥，並無發現生長與防禦間權衡作用的不良影響。以LsGRP1C合成胜肽澆灌處理阿拉伯芥可以誘發植株產生預警效應，而以相同方式處理SUMO-LsGRP1∆SS∆C則無此效果，顯示LsGRP1C為此預警調節之主效區段。LsGRP1於不同植物上皆可啟動預警的功能，推測植物種間可能具有相似的LsGRP1受體，本研究以阿拉伯芥受體突變株測試LsGRP1啟動預警的程度，初步推篩選AtWAK2為阿拉伯芥的LsGRP1候選受體。將LsGRP1以澆灌方式施用於田間草莓與番茄植株，對植株防禦與生產皆有正面效益，顯示LsGRP1具有應用於田間作物健康管理的潛力。

With the ever-changing climate and rising of food demand, agriculture is facing severe disease threats and production challenges. Implementation of plant health managements in conventional farming is important for effective disease control and reducing hazardous pesticide impact to the environment. In this study, the main region of Lilium protein LsGRP1 responsible for systemic defense mediation and the corresponding plant receptor was explored. The potential of LsGRP1 applied as a priming stimulus in the field was evaluated. By assessing the defense responses of SUMO-LsGRP1∆SS-pretreated Arabidopsis seedlings and tomatoes triggered by flg22, LsGRP1-triggered priming effect was verified. Meanwhile, negative effects caused by growth-defense trade-off were not observed. In addition, synthetic peptide LsGRP1C triggered priming but not the SUMO-LsGRP1∆SS∆C, showing that LsGRP1C is the main functioning region for the priming effect. The facts that LsGRP1 triggered priming on different plant species, implicated the presence of common receptor in plants. Among the receptor mutats of Arabidopsis, AtWAK2 was screened as a candidate receptor of LsGRP1. Further field assays showed that the plant defenses of strawberry and tomato could be triggered by LsGRP1 which also increased plant production, indicating the application potential of LsGRP1 in the plant health managment.