A Biocontrol Strain of Bacillus subtilis WXCDD105 Used to Control Tomato Botrytis cinerea and Cladosporium fulvum Cooke and Promote the Growth of Seedlings

Abstract

In this study, a strain named WXCDD105, which has strong antagonistic effects on Botrytis cinerea and Cladosporium fulvum Cooke, was screened out from the rhizosphere of healthy tomato plants. The tomato plants had inhibition diameter zones of 5.00 mm during the dual culture for four days. Based on the morphological and physiological characteristics, the 16S rDNA sequence, and the gyrB gene sequence analysis, the strain WXCDD105 was identified as Bacillus subtilis suBap. subtilis. The results of the mycelial growth test showed that the sterile filtrate of the strain WXCDD105 could significantly inhibit mycelial growth of Botrytis cinerea and Cladosporium fulvum Cooke. The inhibition rates were 95.28 and 94.44%, respectively. The potting experiment showed that the strain WXCDD105 made effective the control of tomato gray mold and tomato leaf mold. The control efficiencies were 74.70 and 72.07%. The antagonistic test results showed that the strain WXCDD105 had different degrees of inhibition on 10 kinds of plant pathogenic fungi and the average inhibition rates were more than 80%. We also found that the strain WXCDD105 stimulated both the seed germination and seedling growth of tomatoes. Using the fermentation liquid of WXCDD105 (108 cfu·mL−1) to treat the seeds, the germination rate and radicle length were increased. Under the treatment of the fermentation liquid of the strain WXCDD105 (106 cfu·mL−1), nearly all physiological indexes of tomato seedlings were significantly higher than that of the control groups. This could not only keep the nutritional quality of tomato fruits but also prevent them from rotting. This study provided us with an excellent strain for biological control of tomato gray mold, tomato leaf mold, and tomato growth promotion. This also laid the technical foundation for its application.

Antifungal mechanism of Streptomyces ma. FS‐4 on fusarium wilt of banana

“…Numerous studies have pointed out that many antifungal agents can cause programmed cell death of filamentous fungi through oxidative stress (Jeong et al 2016;Wang et al 2018;Alijani et al 2019). In our study, the induction of oxidative stress on the target fungus by FS-4 crude extract was determined.…”

“…The fluorescence intensity of the supernatant was measured by a fluorescence spectrophotometer with excitation and emission wavelengths of 488 and 525 nm respectively. The ROS content was also detected (Wang et al 2018).…”

“…In addition, Streptomyces can secrete a variety of cell wall hydrolases, such as chitinase (Pageni et al 2014), glucanase (Passari et al 2015), cellulose (Singh and Gaur 2016), nuclease (He et al 2020) and so on. The cell wall of pathogenic bacteria is used for their own growth by breaking down nutrients that cause the death of pathogenic bacteria (Wang et al 2018).…”

A Biocontrol Strain of Pseudomonas aeruginosa CQ-40 Promote Growth and Control Botrytis cinerea in Tomato

“…All 30 plants per treatment were used for disease symptom investigation. The plant disease index (DI), which would represent both disease incidence and symptom severity, can be calculated as: DI = (ΣDi × Dd)/(Mi × Md) × 100, where i means a 0–4 disease level and Mi means plant number of reaction i, and Dd means total number of leaves investigated [ 38 ].…”

Effect of Some Bioagents on Cladosporium cucumerinum Causing Cladosporium Leaf Spot: A New Challenge in Watermelon Production in Egypt.

“…Bio-control agents such as C. globosum, G. catenulatum, T. harzianum, B. subtilis, and P. fluorescens have the ability to control cladosporium leaf spots (Huang 1978;Xiao and Li. 2013;Sandoval, et al, 2009 andWang et al, 2018) and enhance the plant growth (Compant et al, 2005).…”