White mold intensity on common bean in response to plant density, irrigation frequency, grass mulching, Trichoderma spp., and fungicide

Abstract

The purpose of this study was to evaluate the efficiency of integrated managements on white mold control on common bean. Initially, in vitro testing was made to assess the antagonism of 11 Trichoderma isolates against Sclerotinia sclerotiorum and to investigate fungicides (fluazinam and procymidone) inhibitory effects on those fungi. In two field experiments the following combinations were tested: irrigation frequencies (seven or 14 days), plant densities (six or 12 plants per meter), and three disease controls (untreated control, fungicide or Trichoderma spp.). In a third experiment plant densities were replaced by grass mulching treatments (with or without mulching). Fluazinam was applied at 45 and 55 days after emergence (DAE). The antagonists T. harzianum (experiments 1 and 3) and T. stromatica (experiment 2) were applied through sprinkler irrigation at 10 and 25 DAE, respectively. Most of the Trichoderma spp. were effective against the pathogen in vitro. Fluazinam was more toxic than procymidone to both the pathogen and the antagonist. Fungicide applications increased yield between 32 % and 41 %. In field one application of Trichoderma spp. did not reduce disease intensity and did not increase yield. The reduction from 12 to six plants per meter did not decrease yield, and disease severity diminished in one of the two experiments. It is concluded that of the strategies for white mold control just reduction of plant density and applications of fungicide were efficient.

Breeding Common Bean for Resistance to White Mold: A Review

“…Nonetheless, Peachery et al (2006) reported reduced white mold severity and increased pod yield in green bean due to increased‐row spacing. Paula Junior et al (2009) and Vieira et al (2010) obtained similar results in dry bean from reduced within‐row plant populations. Common bean breeding lines with moderate levels of white mold resistance provided adequate control and did not significantly respond to fungicidal applications (Miklas et al, 2013).…”

Chemical and biological control of Sclerotinia stem rot in the soybean crop

“…Many in vivo studies have been conducted to evaluate the efficacy of fluazinam and procymidone in the control of diseases caused by S. sclerotiorum in common bean crops (PAULA JÚNIOR et al, 2009).…”

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

“…Nesse trabalho, os autores após relacionarem o sucesso obtido no campo com os testes in vitro, conseguiu identificar enzimas (NAGase e β-1,3-glucanase) e o próprio parasitismo exercido pelo fungo, como componentes-chave durante o processo de controle biológico. Assim, tem-se que os principais objetos de estudo realizados no Brasil em experimentos de campo que podem ser apontados são (1) a seleção de isolados ou avaliação de isolados provenientes de produtos comerciais atualmente disponíveis (Görgen et al, 2009); (2) identificar quais mecanismos de controle estão mais relacionados com o sucesso obtido no campo (Geraldine et al, 2013) e, (3) avaliar o controle biológico juntamente com outras práticas culturais, mensurando-se seus efeitos, dependendo da prática adotada (Paula Júnior et al, 2009).…”