Epidemiology and strategies for chemical management of powdery mildew in mango

Abstract

-The objective of this work was to evaluate phytosanitary strategies for the chemical control of powdery mildew (Oidium mangiferae) in mango, based on the alternation of active ingredients with different modes and sites of action, and to determine the environmental and epidemiological conditions that favor the development of the disease. The experiment was conducted in Guerrero, México, in commercial orchards, within a program for the development of fungicide spraying strategies. Epidemic curves were used on temporal analyses of the disease for: incidence; area under disease progression curve (AUDPC); severity; and conidial seasonality and its relationships with meteorological parameters. The disease was better controlled with the application of systemic fungicide followed by contact fungicide with multisite activity. The first symptoms appeared 30 days after the issuance of shoots, and the most susceptible phenological (critical) stages were at full bloom and at the onset of fruit with 8-15 mm. Optimum conditions for the development of powdery mildew, which maximizes the density of airborne spores, are temperatures higher than 30°C and relative humidity over 90%.Index terms: Mangifera indica, Oidium mangiferae, epidemics, fungicide resistance, integrated pest management, multisite fungicides. Epidemiologia e estratégias para o manejo químico do míldio-pulverulento em mangueiraResumo -O objetivo deste trabalho foi avaliar estratégias fitossanitárias para o controle químico do míldio-da-mangueira (Oidium mangiferae), baseadas na alternação de princípios ativos com diferentes modos e sítios de ação, e determinar as condições ambientais e epidemiológicas que favorecem o desenvolvimento da doença. O experimento foi realizado em Guerrero, México, em pomares comerciais, no âmbito de um programa para o desenvolvimento de estratégias de pulverização com fungicida. Curvas epidêmicas foram utilizadas em análises temporais da doença quanto à: incidência; área abaixo da curva de progresso da doença (AACPD); severidade; e sazonalidade dos conídios e sua relação com parâmetros meteorológicos. A doença foi mais bem controlada com a aplicação de fungicida sistêmico seguido de fungicida de contato, com atividade multissítio. Os primeiros sintomas apareceram 30 dias após a emissão dos brotos, e os estádios fenológicos mais sensíveis (críticos) foram o de floração completa e o de frutos com 8-15 mm. As condições ótimas para o desenvolvimento do oídio, que maximizam a densidade de esporos no ar, são temperatura acima de 30°C e umidade relativa superior a 90%.Termos para indexação: Mangifera indica, Oidium mangiferae, epidemia, resistência a fungicidas, manejo integrado de pragas, fungicidas multilocais.

Mango Diseases: Impact of Fungicides

“…The incidence caused by this disease varied from 31.50 to 93.00% on different sensitive mango varieties. The pathogen develops in dry and cold environments but reaches greater severity at 90% relative humidity (RH) and 20-25°C [74][75][76][77][78][79][80].…”

Dieback of Mango and Cutting Method Impact on the Regeneration of Tree in the Sudano-Sahelian Zone

“…The leaves of the trees wither out and remain attached to the dying tree 12,14,15 . These symptoms may be found alone or in a combination of two or more symptoms in different mango orchards in Brazil or Pakistan 16,17 . The mortality of the tree is usually by the blockage of vascular bundles in the proper flow of nutrients 18 .…”

Eficacia de insecticidas botánicos y biorracionales para el control de trips (Thysanoptera: Thripidae) en árboles de mango en Veracruz, México

“…), powdery mildew (Oidium mangiferae), Witches' Broom (Fusarium spp.) and rotting and dieback (Lasiodiplodia theobromae) (Omar et al, 2018;Pérez et al, 2017;Tovar-Pedraza et al, 2020;Rodríguez-Gálvez et al, 2017). As for arthropod pests, where in high populations they cause significant losses (Abushosha et al, 2017;Aguirre et al, 2013;Ayala-Ortega et al, 2019;López-Guillén et al, 2014;Duran-Trujillo et al, 2017; Virgen- Sánchez et al, 2011).…”