Biocontrol efficacy of Bacillus velezensis HC-8 against powdery mildew of honeysuckle caused by Erysiphe lonicerae var. lonicerae

The powdery mildew caused by air borne pathogen (Podosphaera fusca) is an important disease of cucurbits including melon (Cucumis melo L.) plants. Three antagonistic bacterial strains (M4, M10 and M11); isolated from the melon plants were tested for antagonistic activity against P. fusca and soil-borne pathogens of melon plants (Monosporascus cannonballus, Fusarium oxysporum f. spp. melonis, F. solani and Phomopsis spp.). All the three strains were identified as Bacillus velezensis based on sequence analysis of gyrase subunit A (gyrA) gene sequence. The bacterial strains showed significant antagonistic activity against soil and air borne pathogenic fungi. Among all strains, M10 showed a broad spectrum of mycelial growth inhibition against phytopathogenic fungi. The tested culture broth did not affect the pollen fertilization, flowering, fruit rot occurrence and fruit set development during blooming and cultivation season of the melon plants. The M10 culture broth stored for 3 and 6 months displayed biocontrol efficiency of 73.2 and 72.3%, respectively. Application of mixed solution of M10 culture broth + paraffin oil strongly suppressed the incidence and spread of powdery mildew. These results suggested that the combination of paraffin oil and B. velezensis M10 culture broth is an ecofriendly approach and possess strong biocontrol potential against melon powdery mildew and can also be used as antifungal agents for several plant pathogens. © 2021 Friends Science Publishers

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Biocontrol of Leaf Mustard Powdery Mildew Caused by Erysiphe cruciferarm using Bacillus velezensis YP2

The Korean Journal of Pesticide Science ◽

10.7585/kjps.2016.20.4.369 ◽

2016 ◽

Vol 20 (4) ◽

pp. 369-374 ◽

Cited By ~ 3

Author(s):

Sang Yeob Lee ◽

Hang Yeon Weon ◽

Jeong Jun Kim ◽

Ji Hee Han

Keyword(s):

Powdery Mildew ◽

Bacillus Velezensis

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Microscopy studies of powdery mildew on summer squash

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010008691x ◽

1991 ◽

Vol 49 ◽

pp. 520-521

Author(s):

John S. Gardner ◽

W. M. Hess

Keyword(s):

Powdery Mildew ◽

Tip Growth ◽

Hyphal Growth ◽

Plant Tissues ◽

Vegetative Hypha ◽

Powdery Mildews ◽

Summer Squash ◽

Conidial Formation ◽

Polar Tip Growth ◽

Short Conidiophore

Powdery mildews are characterized by the appearance of spots or patches of a white to grayish, powdery, mildewy growth on plant tissues, entire leaves or other organs. Ervsiphe cichoracearum, the powdery mildew of cucurbits is among the most serious parasites, and the most common. The conidia are formed similar to the process described for Ervsiphe graminis by Cole and Samson. Theconidial chains mature basipetally from a short, conidiophore mother-cell at the base of the fertile hypha which arises holoblastically from the conidiophore. During early development it probably elongates by polar-tip growth like a vegetative hypha. A septum forms just above the conidiophore apex. Additional septa develop in acropetal succession. However, the conidia of E. cichoracearum are more doliform than condia from E. graminis. The purpose of these investigations was to use scanning electron microscopy (SEM) to demonstrate the nature of hyphal growth and conidial formation of E. cichoracearum on field-grown squash leaves.

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