利用植物免疫力防治病害的現況與展望

Abstract

植物免疫力乃植物與病原交互作用時，藉由一連串訊息分子傳遞誘發防禦反應，以抵抗病原入侵的能力；亦可藉根圈有益微生物誘導植物免疫力的提升。植物根圈環境中擁有豐富的微生物相，其中植物促生根圈細菌 (plant growth-promoting rhizobacteria, PGPR)可激發植物之免疫力，且不會影響植物的生長與發育，甚至具有促進植物生長的能力。已知植物促生根圈細菌可保護植物，避免真菌、細菌、病毒、線蟲等病原的入侵，多數Pseudomonas 及Bacillus 之種類具有此能力，可開發應用於植物病害之生物防治。誘發植物免疫力會因細菌與植物間的辨識造成植物抗病程度不一，選用適當的生物防治菌株始可減少病害之發生，並得降低田間農藥使用量、減少環境汙染及避免病原菌抗藥菌株的產生。 Interactions between plant and pathogen can induce plant immunity by a series of signal transduction and activation of plant defense responses, giving resistance to pathogen attacks; in addition, plant immunity can be activated by beneficial microorganisms present in the rhizosphere. In the plant rhizosphere, there are plenty of organisms; among them, plant growth-promoting rhizobacteria (PGPR) are able to activate plant immunity, and are capable of promoting plant growth and development without adverse effect. PGPR are able to protect plants from attacks by different kinds of pathogens, including fungi, bacteria, virus, and nematode. Many species of Pseudomonas and Bacillus with plant growth-promoting activity can be applied for the biocontrol of plant diseases. Activation of plant immunity depends on the recognition of bacterium by the plant and the level of disease resistance being induced. Use of suitable biocontrol agents can improve disease suppression effect; it would also decrease the amount of agrochemical applied, environmental pollution and the generation of drug resistant strains of pathogens.