In VitroAntagonistic Characteristics of Bacilli Isolates againstTrichodermaspp. and Three Species of Mushrooms

Abstract

Twenty isolates of Bacillus species obtained from livestock manure composts and cotton-waste composts were tested for their antagonistic effects in vitro against three green mold pathogens of mushrooms (Trichoderma harzianum, T. koningii, and T. viridescens). However, there exists a possibility Bacillus species may have antagonistic effects against mushrooms themselves, and thus the same 20 isolates were tested in vitro against three species of mushrooms (Flammulina velutipes, Lentinus edodes, and Pleurotus ostreatus). Of the 20 Bacillus species isolates tested, two inhibited mycelial growth of T. harzianum, seven that of T. koningii, and eight that of T. viridescens. Importantly, the bacterial isolates M27 and RM29 strongly inhibited mycelial growth of all the Trichoderma spp. isolates tested. The isolate M27 was subsequently identified as the most effective in inhibiting mycelial growth of all the Trichoderma species. Interesting results of the effect Bacillus isolates had upon the mushroom species followed. It was found that most Bacillus isolates except 5T33 at least somewhat inhibited mycelial growth of the three mushroom species or some of the mushrooms. Furhermore, the antagonistic effects of the bacterial isolates against the three species of mushrooms varied depending on the mushroom species, suggesting a role for mushroom type in the mechanism of inhibition. The bacterial isolates M27 and RM29 were identified as having the most antagonistic activity, inhibiting mycelial growth of all the Trichoderma spp. as well as mycelial growth of the three species of mushrooms. These results suggest that the bacterial isolates and their antagonistic effects on green mold pathogens should be further studied for their practical use for biological control of green mold in the growing room of the mushrooms.

Impact of Bacillus subtilis QST713 mushroom grain spawn treatment on yield and green mould control

“…The tested B. subtilis QST713 did not inhibit the growth of A. bisporus mycelia in plots without the pathogen, which is consistent with the results of experiments conducted by Milijašević-Marčić et al (2017) in button mushroom, and Nagy et al (2012) in oyster mushroom (Pleurotus ostreatus). Conversely, Kim et al (2008) reported slightly inhibited mycelial growth of edible mushrooms, enoki (Flammulina velutipes), shiitake (Lentinula edodes) and oyster mushrooms in Korea, as did Kosanović et al (2013) in A. bisporus, too.…”

Multistrain versus single-strain plant growth promoting microbial inoculants - The compatibility issue

“…In the study of Thilagavathi et al (2017) mixture of incompatible B. subtilis Bs16 with Trichoderma viride strains Tv1 and/or Tv13, had the same or less eff ect on inhibition of Macrophomina phaseolina and produced greengram plants with a lower vigour index and germination percentage relative to their individual application. Bacillus species show strong antagonistic activity against other benefi cial bacteria (Simoes et al, 2007) and fungi (Kim et al, 2008;Fuga et al, 2016), thus making the prior examination of compatibility a necessary step for the construction of an eff ective Bacillusbased mixture.…”

Increased Biological Activity of Aneurinibacillus migulanus Strains Correlates with the Production of New Gramicidin Secondary Metabolites

“…BCAs are antagonistic to plant pathogens through antibiosis, competition for nutrients and infection sites on the plant surface, hyperparasitism and by induction of host resistance (Kim et al, 2008; Chandel et al, 2010; Alenezi et al, 2016b). An additional advantage of Bacillus species is their ability to produce highly resilient endospores during unfavorable environmental conditions, allowing efficient storage of Bacillus -based BCA preparations (Piret and Demain, 1982).…”