The antagonistic activity of marine actinomycetes from mangrove ecosystem against phytopathogenic fungi Colletotrichum sp. KA

Abstract

Abstract. Fadhilah QG, Santoso I, Yasman. 2021. The antagonistic activity of marine actinomycetes from mangrove ecosystem against phytopathogenic fungi Colletotrichum sp. KA. Biodiversitas 22: 642-649. Marine actinomycetes from mangrove ecosystems are known to be potential antifungal-producing isolates against phytopathogenic fungi. The aim of this research was to obtain potential marine actinomycetes isolates against the phytopathogenic fungi Colletotrichum sp. KA. Screening of 15 marine actinomycetes isolates using a dual culture method with a plug technique showed that 80% of isolates have antagonistic activity, represented as a percentage of growth inhibition range from 47.96% to 84.94%. Among 12 potential isolates, six isolates (SM4, SM11, SM14, SM15, SM18, and SM20) were evaluated for delayed antagonistic activity with incubation periods of 6, 9, and 12 days using the plug and streak techniques. The results showed that the percentage of growth inhibition of selected isolates inclined to increase along with the incubation period prior to inoculation of Colletotrichum sp. KA. Delayed antagonist assays using the streak technique resulted in higher inhibition results compared to the plug technique. Furthermore, the non-delayed assays of the two selected isolates, SM11 and SM15, also inhibited Colletotrichum sp. KA 57.99% and 59.88%, respectively. The delayed antagonist assay with a shorter incubation period of the two selected isolates also showed an increased percentage of growth inhibition of Colletotrichum sp. KA. According to our research, the delayed antagonistic assay of marine actinomycetes isolates with a 12-day incubation period using a plug technique was representative to evaluate the percentage of growth inhibition.

Figure 3 from: Fadhilah QG, Santoso I, Maryanto AE, Abdullah S, Yasman Y (2021) Evaluation of the antifungal activity of marine actinomycetes isolates against the phytopathogenic fungi Colletotrichum siamense KA: A preliminary study for new antifungal compound discovery. Pharmacia 68(4): 837-843. https://doi.org/10.3897/pharmacia.68.e72817

“…Belonging to actinomycetes, the genus Streptomyces can control plant pathogens through various mechanisms, such as the production of antimicrobial and other metabolite compounds (Olanrewaju and Babalola 2019). The percentage inhibition of all isolates in antibiosis assay was lower than obtained in our previous study of antagonist assay using plug technique, for example, SM14 at 12 days was only 64.90% in antibiosis assay, whereas in antagonist assay was 82.34% (Fadhilah et al 2021). This phenomenon may be due to the inhibition in antibiosis assays is represented solely by the antifungal compound activity itself.…”

“…This phenomenon may be due to the inhibition in antibiosis assays is represented solely by the antifungal compound activity itself. Meanwhile, concerning the antagonism assay, it was assumed that the inhibition was caused not only by antifungal compounds but also by direct interspecific competition with the involved species for food and space (Fadhilah et al 2021). As a biocontrol agent, Streptomyces has been reported to have various antagonistic mechanisms, including competition for nutrients and space and antibiosis, as well as parasitism (Law et al 2017).…”

“…The preliminary study to discover new antifungal compounds had been done by screening the marine actinomycetes isolates that have antifungal activity. Our previous study for discovering potential actinomycetes reported that 80% of the marine actinomycetes isolated from the mangrove ecosystem in Pramuka Island, Jakarta, Indonesia demonstrated antagonistic activity against the phytopathogenic fungi, Colletotrichum siamense KA (Fadhilah et al 2021). The aim of the present study was to evaluate the antifungal activity of the three marine actinomycetes isolates (SM11, SM14, and SM15) with the highest antagonistic activity using antibiosis assay.…”

Diversity of phyllospheric Actinomycetes in Liliaceae plants and their potential as growth inhibitors of Alternaria porri

“…Ohike et al (2018) tested the inhibition effect of Actinomycetes against eight types of phytopathogenic fungi and found that all isolates exhibited positive results on the mycelium. Fadhilah et al (2021) successfully isolated marine Actinomycetes from mangrove ecosystems. The isolates demonstrated antagonistic activity against Colletotrichum sp., with an inhibition percentage of 84.94%.…”

Evaluation of the antifungal activity of marine actinomycetes isolates against the phytopathogenic fungi Colletotrichum siamense KA: A preliminary study for new antifungal compound discovery

“…The fermentation periods for the antifungal compounds produced from the isolates lasted 6, 9, and 12 days based on our previous study. It was assumed that the marine actinomycetes isolates had been in a stationary growth phase (Fadhilah et al 2021). Bioactive compounds such as antibiotics are synthesized during stationary growth phases when the nutrients in the medium are depleted (Fedorenko et al 2015).…”