Biocontrol potential ofMicrobacterium maritypicumSneb159 againstHeterodera glycines

Abstract

BACKGROUND The soybean cyst nematode Heterodera glycines (Ichinohe) is the most devastating pathogen affecting soybean production worldwide. Biocontrol agents have become eco‐friendly candidates to control pathogens. The aim of this study was to discover novel biocontrol agents against H. glycines. RESULTS Microbacterium maritypicum Sneb159, screened from 804 strains, effectively reduced the number of females in field experiments conducted in 2014 and 2015. The stability and efficiency of H. glycines control by Sneb159 was further assessed in growth chamber and field experiments. Sneb159 decreased H. glycines population densities, especially the number of females by 43.9%–67.7%. To confirm Sneb159 induced plant resistance, a split‐root assay was conducted. Sneb159 induced local and systemic resistance to suppress the penetration and development of H. glycines, and enhanced the gene expression of PR2, PR3b, and JAZ1, involved in the salicylic acid and jasmonic acid pathways. CONCLUSION This is the first report of M. maritypicum Sneb159 suppressing H. glycines infection. This effect may be the result of Sneb159‐induced resistance. Our study indicates that M. maritypicum Sneb159 is a promising biocontrol agent against H. glycines. © 2019 Society of Chemical Industry

Isolation and identification of induced systemic resistance determinants from Bacillus simplex Sneb545 against Heterodera glycines

“…The cysts were obtained by pouring infested soil through a nested 850 μm pore over 250 μm pore sifter followed by centrifugal flotation in a 35% sucrose solution 61,62 . The cysts were surface-sterilised using 0.5% sodium hypochlorite for 3 min, rinsed with sterile distilled water seven times, and then incubated at 26 °C in the dark 14 . Second-stage juveniles (J2) were collected for SCN inoculum (1,000 J2 mL -1 ).…”

“…The genes expression of PR genes were detected, and Actin 11 was used as reference gene for normalizing the target genes. The primers for PR1 67 , PR2 68 , PR3a 58 , PR3b 58 , PR10 59 and Actin 11 14 were described in Table 1 . The 10-μl reaction mixtures of qRT-PCR contained 5 μL 2 × TB Green premix (Takara), 1 μL cDNA template (1:5 dilution), 3.2 μL sterile distilled water, and 0.8 μL of each forward and reverse primers for selected genes.…”

“…The exogenous stimulation of PGPR can induce a plant immune response, which can directly induce salicylic acid (SA)-and/or jasmonic acid (JA)-dependent defence responses 11,12 . Previous studies have indicated that the expression of SA-and JA-pathway-related genes could be up-regulated in host plants in response to SCN by coating seeds with bacteria [13][14][15] .…”

Efficacy ofBacillus megateriumstrain Sneb207 against soybean cyst nematode (Heterodera glycines) in soybean

“…9 Similarly, Sinarhizobium fredii Sneb183 and Microbacterium maritypicum Sneb159 have displayed their potential to inhibit nematode development, and induce systemic resistance in soybean plant, respectively. 3,10 Moreover, soybean seed coated with bacteria including Bacillus simple, B. megaterium and S. fredii has been shown to reduce SCN reproduction and promote plant growth and yield in field trials. 6 Therefore, bacterial biocontrol agents can be used to control soybean cyst nematode.…”

“…20 In the last few years, ISR mediated by plant growth-promoting bacteria (e.g. Bacillus sp., Klebsiella pneumoniae, Microbacterium maritypicum, R. etli) has been reported against a wide range of important plant-parasitic nematodes, such as H. glycines, 3,10,21 Meloidogyne incognita, 22 and Globodera pallida. 23 Moreover, GmACS9b, GmEDS1, GmPAD4, GmSAMT1, and GmNPR1-1 genes play an important role in induced systemic resistance against nematodes.…”