Supression of seed borne Cladosporium herbarum on common bean seed by Trichoderma harzianum and promotion of seedling development

Abstract

Trichoderma harzianum isolates have been broadly used for biocontrol of plant diseases caused by fungi. Cladosporium herbarum is a common saprophyte and seed borne fungus, which is easy to manipulate under controlled conditions. It was chosen as a model to test the effectivity of seed treatments with T. harzianum. Common bean seeds (cv. Pérola) contaminated with C. herbarum were treated with conidial suspension (CS) and autoclaved filtrate (AF) of five isolates of T. harzianum and subsequently submitted to health and germination tests. The proportion of normal seedlings formed, the length of roots, hypocotyls and leaves, and total plantlet length, total plantlet biomass, root mass ratio (RMR), stem mass ratio (SMR), leaf mass ratio (LMR), aerial part/root system ratio (AP/RS) and leaf area were also evaluated. Isolates CEN289 and CEN290 (CS and AF) provided 66 to 77% of supression of C. herbarum on seeds and a higher number of normal seedlings as compared with control. It also yielded a higher total biomass of plantlets. Moreover treatment with isolates CEN289 and CEN290 increased root and stem length in the experiments with CS. Such results indicate the potential of T. harzianum for seed treatment and suggest that it should be further tested as control for seed borne fungal diseases and as a plant growth promoter. The better performance found for CEN289 and CEN290 confirms the variability in terms of biocontrol activity among strains of T. harzianum.

Trichoderma harzianum no tratamento de sementes de Cladosporium herbarum, Sclerotinia sclerotiorum e no aumento de crescimento do feijoeiro no Brasil

“…no controle de fitopatógenos, certos isolados podem estimular o desenvolvimento de plantas (Harman et al, 2004). Recentemente, a promoção de crescimento do feijoeiro pelo emprego de Trichoderma tem sido objeto de estudo no Brasil (Aguiar et al, 2014;Guimarães et al, 2014). Experimentos conduzidos em casa de vegetação por Pedro et al, (2012), mostraram que isolados de Trichoderma podem proporcionar aumentos superiores a 30% na produção de matéria seca da parte aérea das plantas de feijão.…”

“…(Pers.) Link está associado com sementes de feijão durante o armazenamento e é capaz de provocar danos na germinação e no vigor, especialmente de sementes não tratadas (Guimarães et al, 2014). Já em relação a Sclerotinia sclerotiorum (Lib.)…”

“…). Para exemplificar essa evidência, pode-se citar o trabalho deGuimarães et al, (2014), onde o tratamento de sementes com suspensão de conídios de T. harzianum proporcionaram de 67 a Cladosporium sp. nas sementes.…”

Ação de metabólitos voláteis e não voláteis de Trichoderma harzianum sobre o crescimento de Cladosporium herbarum

“…sobre Cladosporium sp. (CARVALHO et al, 2011;GUIMARÃES et al, 2014). Neste contexto, trabalhos na área devem atentar-se para o fato de que os agentes de controle biológico podem agir contra patógenos, usando um ou mais mecanismos, tais como competição e, principalmente a antibiose (DEMIRCI et al, 2011).…”

Biological control of white mold by Trichoderma harzianum in common bean under field conditions

“…However, all three isolates proved to be effective for management of Fusarium wilt of common bean in field conditions (Carvalho et al, , 2015Guimarães et al, 2014). Therefore, also due to their high capacity for spore production, these isolates are considered a promising tool for biocontrol of white mold in common bean.…”