Panthi Urbashi, McCallum Brent, Kovalchuk Igor, Rampitsch Christof, Badea Ana, Yao Zhen, Bilichak Andriy
Agriculture and Agri-Food Canada, Morden Research and Development Centre, 101 Rte 100 #100, Morden, MB R6M 1Y5, Canada.
Department of Biological Sciences, University of Lethbridge, 4401 University Dr W, Lethbridge, AB T1K 3M4, Canada.
J Genet Eng Biotechnol. 2024 Mar;22(1):100357. doi: 10.1016/j.jgeb.2024.100357. Epub 2024 Feb 15.
Screening and developing novel antifungal agents with minimal environmental impact are needed to maintain and increase crop production, which is constantly threatened by various pathogens. Small peptides with antimicrobial and antifungal activities have been known to play an important role in plant defense both at the pathogen level by suppressing its growth and proliferation as well as at the host level through activation or priming of the plant's immune system for a faster, more robust response against fungi. Rust fungi (Pucciniales) are plant pathogens that can infect key crops and overcome resistance genes introduced in elite wheat cultivars.
We performed an in vitro screening of 18 peptides predominantly of plant origin with antifungal or antimicrobial activity for their ability to inhibit leaf rust (Puccinia triticina, CCDS-96-14-1 isolate) urediniospore germination. Nine peptides demonstrated significant fungicidal properties compared to the control. Foliar application of the top three candidates, β-purothionin, Purothionin-α2 and Defensin-2, decreased the severity of leaf rust infection in wheat (Triticum aestivum L.) seedlings. Additionally, increased pathogen resistance was paralleled by elevated expression of defense-related genes.
Identified antifungal peptides could potentially be engineered in the wheat genome to provide an alternative source of genetic resistance to leaf rust.
为维持和增加农作物产量，需要筛选和开发对环境影响最小的新型抗真菌剂，因为农作物产量不断受到各种病原体的威胁。已知具有抗菌和抗真菌活性的小肽在植物防御中发挥重要作用，在病原体层面通过抑制其生长和增殖，在宿主层面通过激活或启动植物免疫系统，使其对真菌做出更快、更强有力的反应。锈菌（柄锈菌目）是能够感染关键作物并克服优良小麦品种中引入的抗性基因的植物病原体。
我们对18种主要来源于植物且具有抗真菌或抗菌活性的肽进行了体外筛选，以评估它们抑制叶锈菌（小麦叶锈菌，CCDS - 96 - 14 - 1分离株）夏孢子萌发的能力。与对照相比，9种肽表现出显著的杀真菌特性。对排名前三的候选肽β - 硫堇、α2 - 硫堇和防御素 - 2进行叶面喷施，降低了小麦（普通小麦）幼苗叶锈病感染的严重程度。此外，病原体抗性的增强与防御相关基因表达的升高相平行。
鉴定出的抗真菌肽有可能在小麦基因组中进行工程改造，以提供对叶锈病的另一种遗传抗性来源。
