KR-102961740-B1 - Streptomyces recifensis SN1E1 strain having antimicrobial activity against plant pathogen and uses thereof

Abstract

The present invention relates to a Streptomyces recifensis SN1E1 strain having antimicrobial activity against plant pathogens and the use thereof. Since the Streptomyces recifensis SN1E1 strain of the present invention has the effect of effectively inhibiting the growth of Erwinia amylovora, the causative agent of fire blight in fruit trees, using the strain of the present invention as a biopesticide can avoid soil and water pollution problems caused by conventional synthetic pesticides, thereby enabling the supply of environmentally friendly, high-quality, and safe agricultural products to consumers.

Inventors

• 곽연식
• 이수인

Assignees

• 경상국립대학교산학협력단

Dates

Publication Date

20260507

Application Date

20230531

Claims (8)

1. Streptomyces recifensis SN1E1 strain with accession number KCTC19089P, having antimicrobial activity against Erwinia amylovora .
2. delete
3. A composition for controlling fire blight caused by Erwinia amylovora, containing the strain of claim 1 or a culture solution thereof as an active ingredient.
4. delete
5. A biological pesticide for controlling fruit tree fire blight caused by Erwinia amylovora, containing the strain of claim 1 or a culture solution thereof as an active ingredient.
6. A method for controlling fire blight caused by Erwinia amylovora , comprising the step of applying an effective amount of a composition for controlling fire blight caused by Erwinia amylovora of claim 3 to a plant, plant seeds, or plant planting soil.
7. delete
8. A method for preparing a composition for controlling fruit tree fire blight caused by Erwinia amylovora, comprising the step of culturing the strain of claim 1.

Description

Streptomyces recifensis SN1E1 strain having antimicrobial activity against plant pathogens and uses thereof The present invention relates to a Streptomyces recifensis SN1E1 strain having antibacterial activity against plant pathogens and the use thereof. Fire blight is a type of disease caused by the pathogen * Erwinia amylovora *, and it is a highly contagious bacterial disease, particularly affecting apple and pear crops. Primarily hosting fruit trees belonging to 39 genera and over 180 species of the Rosaceae family, it is characterized by the drying out of tissues such as flowers, leaves, branches, stems, and fruits, turning them dark brown. If symptoms worsen, it forms ulcers on tree trunks or thick branches and eventually kills the tree's roots, rendering the fruit unharvestable. Generally, fire blight pathogens emerge during periods of high rainfall and prolonged flowering, exhibiting rapid spread to host plants in nearby areas. Regarding the transmission pathways of *Erwinia amylovora*, the pathogen primarily overwinters in the tissues of tree trunks or branch margins. It becomes active starting in the spring as flowering approaches, transmitting bacterial mucus to other plants via pollinators such as insects (bees, butterflies, flies, etc.) and birds, as well as through natural means (wind and rain). Additionally, domestic epidemiological studies on fire blight infections have reported that transmission can also occur via pruning tools or humans. Fire blight was first reported in the eastern United States in 1780 and has gradually spread through the Mediterranean to Europe, Canada, and New Zealand; recently, its scope has expanded to Central Asia adjacent to China. In Korea, the disease first appeared in Anseong, Gyeonggi-do and Cheonan, Chungcheongnam-do in 2015, and has been continuously spreading to nearby fruit orchards in Anseong, Cheonan, and Jecheon since 2018. Generally, in Korea, based on the 'Guidelines for Fire Blight Surveillance and Control' specified in the [Plant Areas Act], measures such as burial and orchard closure are carried out for fruit trees confirmed to have fire blight to prevent the spread of the disease. Additionally, all confirmed fruit trees and host plants within a radius of 100 m are collectively buried, and the cultivation of host plants is prohibited for three years. Economic losses caused by fire blight occur not only domestically but also overseas. The apple and pear industries in over 40 countries, including the United States and Europe, have suffered annual economic losses of approximately $10 billion. Furthermore, as fire blight acts as a trade barrier for affected countries during the import and export quarantine stages, significant economic losses are on the rise. To date, no definitive cure for fire blight has been developed. In Korea, efforts are being made to prevent the spread of the disease by implementing two rounds of control measures for affected fruit orchards: a primary winter prevention measure during the dormancy period and an additional antibiotic treatment during the flowering season. One method to combat fire blight in fruit trees is to minimize disease occurrence through horticultural practices. For instance, reducing soil moisture and maintaining a balance of fertilizer nutrients can control infection and spread, but this method cannot fundamentally eliminate the disease. Alternatively, it is possible to treat fire blight by removing infected trees or blackened branches during the winter, when the pathogen is dormant. However, this method requires careful attention to equipment sterilization to prevent the spread of the disease, and since it cannot detect all small lesions or internal infections, it cannot completely eradicate the disease. In addition, fire blight can be controlled on fruit trees infected with the disease by regularly spraying copper compounds or antibiotics. However, the use of copper compounds is often ineffective or causes russeting on the fruit, making it difficult to use universally. Although the use of antibiotics, particularly streptomycin, is more effective and less harmful to fruit than copper compounds, other methods are needed because *Erwinia amylovora* is developing resistance to streptomycin in many U.S. states where it is used, including California, Oregon, Washington, Missouri, and Michigan. Meanwhile, Korean Patent Publication No. 2022-0082675 discloses 'a strain of Pseudomonas cedrina S26-32 for controlling fire blight in fruit trees and its use' and Korean Patent Publication No. 2022-0082673 discloses 'a strain of Arthrobacter parcens S29-14 for controlling fire blight in fruit trees and its use', but there is no description of the Streptomyces recifensis SN1E1 strain of the present invention, which exhibits antibacterial activity against Erwinia amylovora, the causative agent of fire blight in fruit trees. Figure 1 shows the results confirming the antimicrobial activity of the Streptomyces recifensis SN1E1