Isolation and identification of an endophytic bacteria Bacillus sp. K-9 exhibiting biocontrol activity against potato common scab

Abstract

Potato scab is an important soil-borne disease that can signi cantly reduce the quality and economic value of potatoes. The purpose of this study was to isolate, screen and identify endophytic bacteria that have antagonistic and control effects on potato scab disease, and to determine the control effect and yield traits of the selected strains on potato scab disease in eld conditions. A bacterial strain K-9 was isolated from the junction between scab spot and healthy epidermis of potato tuber. The K-9 strain was identi ed as a new species of Bacillus sp. through morphological, physiological and biochemical characterization, and 16S rDNA and gyrB gene sequence analysis. The diameter of the inhibition zone of strain K-9 against Streptomyces scabies on the YME plate was 3.82 cm. The K-9 strain could inhibit eight types of crop pathogens, with the highest inhibition rate (70.39%) against another soil-borne potato disease potato black scurf . In the eld test, the control effect of K-9 strain against potato scab was not signi cantly different from that of mixed bacteria or chemical agents, but the disease index and the scab index in the K-9 treatment were signi cantly lower than in the control. The potato yield in the K-9 treatment was 12.44% higher than the control. In summary, the K-9 strain can prevent not only potato scab, but also increase potato yield.Therefore, the endophytic bacterial K-9 strain may be a potential biological control agent.

Deciphering core microbiota in rhizosphere soil and roots of healthy and Rhizoctonia solani-infected potato plants from various locations

“…The potato's ability to adapt to various climates has made it crucial for both economy and global food security (Xia et al, 2017;Ajayi-Oyetunde and Bradley, 2018;Iradukunda et al, 2022;Shuang et al, 2022). However, its continuous cultivation has led to an increase in black scurf disease, caused by Rhizoctonia solani, affecting potato yields worldwide (Lankau et al, 2020;Zhang X.-Y.…”

Effect of Hydrogen Peroxide on the Soil Microbial Community Structure and Growth of Malus hupehensis Rehd. Seedlings under Replant Conditions

“… 56 Bacillus not only inhibited the reproduction of pathogenic fungi, improved microbial community structure, and enhanced plant disease resistance but also secreted catabolic phytase to increase the amount of free phosphorus in the soil, promoted phosphorus uptake by plants, and improved the crop yield. 59 Making fungi fertilizer from Trichoderma asperellum strain both promoted replanted seeding growth and development, optimized the soil microhabitats, and effectively alleviated ARD. 60 In aquatic and terrestrial habitats, Lophiostom commonly occurs as sapwood on branches, stems, or bark in woody and herbaceous plants.…”

Evaluation of molecular typing methods for some scab-causing Streptomyces strains from Turkey

“…Different phytopathogenic Streptomyces species, which are critical hazardous effects on potatoes have been reported all over the world, especially in USA and Canada (Wanner et al 2009 ), Sweden (Natsume et al 2018 ), China (Liang et al 2019 ), Argentina, Mexico, Finland, South Korea, Japan etc. (Shuang et al 2022 ).…”

“…Scab disease affects some other crops containing beet, carrot, radish, parsnip, and sweet potato (Hill and Lazarovits 2005 ; Planckaert et al 2021 ; Shuang et al 2022 ). Moreover, scab-causing Streptomyces can damage some seedlings of monocotyledonous and dicotyledonous plants.…”