Antimicrobial activities of Trichoderma atroviride against common bean seed-borne Macrophomina phaseolina and Rhizoctonia solani

Abstract

Common bean (Phaseolus vulgaris L.) is the most consumed legume worldwide, with a commercial value surpassing that of all other legume crops combined. Seed-borne fungi cause at least 10% loss in common bean. Standard blotter (SB) and agar plate (AP) techniques were used to identify seed-borne fungi associated with common bean seeds. Thirty-two fungal species comprising 23 genera were detected. Among the fungal pathogens recovered, Macrophomina phaseolina and Rhizoctonia solani were predominant with a higher recovery using the AP technique than SB technique. Antagonistic activities of six Trichoderma isolates associated with healthy common bean seeds were evaluated against both pathogens, M. phaseolina and R. solani through a dual culture assay. Of them, Trichoderma isolate T22 remarkably suppressed the growth of both pathogens (72.42% and 68%, respectively), 5 days after inoculation. Both pathogens were completely overgrown by T22 mycelia, and sclerotia formation by the two pathogens was lacking compared to the control plates, after 8 days. The T22 isolate was morphologically identified as T. atroviride. The scanning electron microscopy (SEM) confirmed the mycoparasitism of T. atroviride T22 against M. phaseolina and R. solani, resulting in mycelium collapse of both pathogens. A total of nine unique volatile compounds of T. atroviride T22 filtrate were identified by GC-MS technique, representing 75.03% of the total components. Among them, 5-hydroxymethylfurfural (46.11%), and 4 H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl-(15.66%) were detected as major components, while furfural (3.14%), hexadecanoic acid, 2-hydroxy-1-(hydroxymethyl) ethyl ester (2.81%), 1,2-cyclopentanedione (2.79%), and 2-furanmethanol (2.09%) were found to be minor compounds. Our results confirmed that T. atroviride T22 can be used as an effective biocontrol agent against M. phaseolina and R. solani, which are pathogens on common beans and many other crops.

Antagonism and molecular identification of <i>Trichoderma</i> isolated from rhizosphere of medicinal plants

“…According to studies by Paul et al (2021), the antagonism exhibited by T. harzianum ranged between 75.01 and 78.22%. A slightly higher inhibition rate (72.42%) than in the present study was observed by El-Benawy et al, (2020) by the T. atroviride isolate T22.…”

“…Screening of the antagonist potential of Trichoderma isolates has been demonstrated in scientific works for several plant pathogenic fungi, such as Macrophomina phaseolina (El-Benawy et al, 2020, Choudhary et al, 2021, Martínez-Salgado et al, 2021, Paul et al, 2021; Fusarium spp. (Pellan et al, 2020;Kumar et al, 2021;Yassin et al, 2021); Sclerotium rolfsii (Kotasthane et al, 2014;Kamel et al, 2020;Blanco et al, 2021) and Sclerotinia sclerotiorum (Marques et al, 2016;Amaral et al, 2018;Sumida et al, 2018;Carvalho et al, 2019).…”

Plantago lagopus extract as a green fungicide induces systemic resistance against Rhizoctonia root rot disease in tomato plants

“…For all these reasons, research is making good progress toward a biological control point of view that could be combined with other methods to make a good plan for fighting plant diseases ( Abo-Zaid et al, 2021 ). Many biocontrol agents are reported to fight R. solani pathogens such as Bacillus subtilis and Trichoderma species, which stop the pathogen’s growth or progress with different strategies like production of siderophores, cell lysis enzymes, or by direct intact (hyperparasitism; Wu et al, 2019 ; El-Benawy et al, 2020 ; Heflish et al, 2021 ). Also, various plant extracts are reported for their antifungal activity against R. solani, including a diverse array of bioactive chemicals that are well-known for their antimicrobial and antifungal activity without causing phytotoxic effects ( Al-Askar and Rashad, 2010 ; Santas et al, 2010 ; Abd-El-Khair and El-Gamal Nadia, 2011 ; Hamza et al, 2016 ; Koka et al, 2017 ; Parveen et al, 2017 ).…”

Biocontrol of Phytophthora xcambivora on Castanea sativa: Selection of Local Trichoderma spp. Isolates for the Management of Ink Disease

“…These features represent a very important characteristic to be evaluated in several species of Trichoderma used as beneficial fungi against several plant pathogens, in both forest and crop patho-systems. In particular, T. harzianum, T. atroviride, T. virens, T. koningiopsis, T. hamatum and T. asperellum were reported to overgrow and sporulate on the target pathogen in dual cultures, the latter considered as a sign of mycoparasitism [21,27,[68][69][70][71].…”