Temporal analysis and fungicide management strategies to control mango anthracnose epidemics in Guerrero, Mexico

Abstract

The temporal progress of anthracnose (Colletotrichum gloeosporioides) epidemics was studied in mango (Mangifera indica) orchards treated with fungicides from different chemical groups, mode of action, and application sequences in two regions of contrasting climates (sub-humid and dry tropics) in Guerrero, Mexico. Full flowering, initial setting, and 8-15mm Ø fruits were identified as critical stages for infection. Epidemics started 20-26 days after swollen buds, and maximum severity was attained at 40-42 days after the first symptoms were detected. The Weibull model described (r²>0.89) anthracnose epidemics in both floral and vegetative flushes. Active ingredients of different fungicide groups, mode of action, and residuality such as myclobutanil, azoxystrobin, cyprodinil+fludioxonil, quinoxyfen, and chlorotalonil + sulfur led to significantly low values (LSD<0.05%) in the Yf, AUDPC and b-1 parameters. The best strategy was to initiate a preventive treatment with a systemic ingredient, independently of its chemical group. Severity of the disease in floral (Fl) and vegetative flushing (Veg) in the sub-humid tropic was related with temperature >30ºC (rFl=0.79-0.86; rVeg=0.80-0.95) and relative humidity > 90% (rFl=0.66-0.86; rVeg=0.67-0.94). In both regions, conidial sporulation was related to temperature >30ºC (r=0.72-0.74), relative humidity <60% (r=0.66), severity (rFl=0.62-0.98; rVeg=0.75-0.97) and dew point <25ºC (r=0.68-0.69)

Mango anthracnose integrated management

“…In the postharvest phase, anthracnose is reported to cause losses of 5 to 20% 6 and the use of synthetic chemical fungicides and treatment with hot water at 52±2 °C for 10 min have been suggested to minimize damage to mango fruits. 7,8 As well as the use of natural and biodegradable biofungicides, such as trans-cinnamaldehyde, citral and phenylacetaldehyde, for the control of anthracnose disease in mango after harvest. 9 Fitzell and Peak 10 determined that spores are the most important source of inoculum in Australia, which are produced on terminal branches, mummified inflorescences, floral bracts and leaves Under laboratory conditions spores are produced over a wide temperature range (10-30 °C) and relative humidity of 95-97%.…”

Efecto in vitro de fungicidas para el control de Colletotrichum SPP., en frutales Manabí - Ecuador

“…Este fitopatógeno tiene mucha importancia en la fruticultura tropical, por los daños económicos que ocasiona al afectar los frutos. El manejo de esta enfermedad se ha fundamentado en prácticas de control cultural y uso de fungicidas químicos (Monteon et al, 2012;Landero et al, 2016) Dada la importancia del patógeno y su necesidad de encontrar un control químico eficiente, la presente investigación determinó la eficiencia in vitro de fungicidas para el control de Colletotrichum spp., en maracuyá y papaya en Manabi -Ecuador.…”