Interaction of Fusarium solani, Macrophomina phaseolina and Rhizoctonia solani as root rot pathogens of Cucumis melo

Maria Alice Formiga Porto,Selma Rogéria De Carvalho Nascimento,Márcia Michelle De Queiroz Ambrósio,Beatriz Letícia Silva Da Cruz,Taffarel Melo Torres

doi:10.1590/0100-5405/182687

Maria Alice Formiga Porto, Selma Rogéria De Carvalho Nascimento + Show 3 more

Open Access

https://doi.org/10.1590/0100-5405/182687

Copy DOI

Abstract

ABSTRACT Root diseases represent one of the main reasons for yield loss in melon crops, especially root and stem rots caused by pathogens like the fungi Fusarium solani (Fs), Macrophomina phaseolina (Mp) and Rhizoctonia solani (Rs), frequently observed in muskmelon either alone or in combination. The objective of this study was to evaluate the effect of the interaction between the pathogens Fs, Mp and Rs on the incidence and severity of root rot and muskmelon development. Two greenhouse experiments were performed using plastic pots with substrate infested with each pathogenic agent alone or in combination. The second experiment was conducted in the same pots that were used in the first experiment. In the first experiment, the disease incidence was higher for the treatment with Fs alone. In the second experiment, the disease incidence and severity were greater for treatment Fs + Rs than for Fs alone. Macrophomina phaseolina was the most commonly isolated pathogen when applied to the plants in a paired mixed inoculum (Fs + Mp and Mp + Rs) in the first experiment. In the second experiment, Fs was more prevalent than the other studied pathogens. Soil infested with Fs had the lowest fresh weight of muskmelon. The pathogens Fs and Mp were more competitive than Rs.

Highlights

A ocorrência de doenças radiculares representa uma das principais causas de perda de rendimento na cultura do melão, com destaque para patógenos causadores das podridões de raízes e colo, como os fungos Fusarium solani (Fs), Macrophomina phaseolina (Mp) e Rhizoctonia solani (Rs), frequentemente observados no meloeiro de forma isolada ou associados
Soil infestation was performed only in the first experiment; the second experiment started seven days after harvest of the first experiment, with a new sowing using the same soil and pots that were used in the first experiment and following the characterization of continuous cropping to examine the behavior of pathogens from one cycle to the other
The highest disease percentage among treatments occurred with the infestation of F. solani alone in the first experiment (Figure 1a), showing a median of 100%

Summary

Introduction

A ocorrência de doenças radiculares representa uma das principais causas de perda de rendimento na cultura do melão, com destaque para patógenos causadores das podridões de raízes e colo, como os fungos Fusarium solani (Fs), Macrophomina phaseolina (Mp) e Rhizoctonia solani (Rs), frequentemente observados no meloeiro de forma isolada ou associados. A incidência da doença foi maior no tratamento com Fs sozinho. A incidência e severidade da doença foram maiores no tratamento Fs + Rs do que no Fs sozinho. Macrophomina phaseolina foi o patógeno isolado com maior frequência quando aplicado às plantas em um inóculo misto aos pares (Fs + Mp e Mp + Rs), no primeiro experimento. The expansion of muskmelon production around the world, including Brazil, has led to an increase in the incidence and severity of diseases, especially those caused by soil-borne pathogens [27]. In Brazil, no reports of percentage losses exist; soil-borne microorganisms are known to be the main cause of diseases and economic losses [27]. Previous studies have shown that associations of soil-borne pathogens commonly occur, causing root and stem rot and collapse. In Brazil, Andrade et al [6] reported mixed infections between F. solani and other soil-borne pathogens in 88.9% evaluated fields

Objectives

Methods

Results