Isolation, screening and in vitro evaluation of bacterial antago-nists from spent mushroom substrate against Colletotrichum musae

Abstract

Colletotrichum musae is a major pathogen in banana fruit which causes heavy losses at the postharvest stage. As a viable alternative to harmful chemical usage and physical control measures, the potential of using bacterial antagonist against C. musae was evaluated in this study. Out of a total of 92 bacterial isolates derived from dilution plates of aqueous extracts of spent mushroom substrate (SMS), 43 isolates were initially selected for screening for antagonistic activity against the C. musae isolate CMK01. Screening of the selected bacterial isolates revealed that 39 of the tested isolates significantly inhibited fungal growth in vitro compared to the control (P <0.05). The diffusible substances secreted by the five selected isolates showed 100% inhibition of colony growth, while (13-58%) inhibition was observed with volatile compounds. Light microscopic observations revealed deformation and blackening of C. musae hyphal tips in the colony margins facing the antagonists. Four of the selected five bacterial isolates were identified with 100% precision as Pseudomonas aeruginosa based on partial 16S rDNA sequences. These promising antagonists have the potential to be developed as effective biocontrol agents against C. musae.

Fungicides and Bioagents: Evaluation of Pathogen Eradication under Laboratory Conditions

“…The pathogen C. musae was isolated from naturally infected banana fruit which is brought from Dhule fruit market showing typical symptoms circular to angular / irregular ring, light to dark brown spots with a dark red or blackish margin were used to isolate the pathogen by tissue segment method [18] on potato dextrose agar (PDA) medium. Further, the seven days old culture of C. musae were used for the in vitro efficacy of bioagents and fungicides test.…”

“…in culture media. Costa and Subasinghe[30,31,18] observed the effect of P. fluorescens on the C. musae. The results regarding the effect of bio agents are also agreements with the many plant pathologists, [32] who also reported that T. harzianum and T. viride were shown to be the most effective in vitro condition against C. gloeosporioides.…”

Assessment of Various Fungicides, Bioagents and Natural Substances on Anthracnose Disease of Banana

“…), which affects both mature and damaged green fruits. Additionally, banana tip rot, crown rot, and blossom end rot have all been caused by C. musae [21,[22][23][24]. The disease typically develops during extended periods of storage and transit that are characterized by low temperatures and high humidity.…”

The Potential of Microbes Isolated from Spent Substrate of Shiitake and Oyster Mushrooms to Induce Resistance Against Early Blight Disease in Tomatoes

“…Spent mushroom substrate can control plant diseases through several mechanisms. The efficacy of spent mushroom compost has been related to the activity of microorganisms that are antagonistic to plant pathogens [7,[10][11][12]. Spent mushroom substrates also contain antimicrobial substances that inhibit pathogen growth [13,14].…”

“…lycopersici [11] and Rhizoctonia solani [12]. Bacterial isolates from spent oyster mushroom substrate were also effective at inhibiting the growth of plant pathogens in vitro, including Colletotrichum musae [10], and Fusarium solani [16].…”