Aislamiento, identificación y daños asociados al síndrome de la muerte súbita en el cultivo de soja en Argentina

Abstract

RESUMENLos objetivos de este trabajo fueron aislar e identificar los agentes causales del síndrome de la muerte súbita (SMS) en muestras provenientes de diferentes localidades de Argentina, y cuantificar la incidencia de la enfermedad y los daños causados a campo en el rendimiento. Se analizaron 215 raíces provenientes de plantas con síntoma foliares típicos de SMS para el aislamiento e identificación de los agentes causales. Para realizar las pruebas de patogenicidad se efectuaron dos bioensayos en invernáculo. Los daños fueron estimados en un ensayo a campo situado en Pergamino a través de la cuantificación del rendimiento de muestras apareadas. El 36% (78 raíces) de las raíces presentó signos de Fusarium, compatibles con los causantes de SMS. Los estudios morfológicos realizados permitieron identificar 35 aislamientos como F. tucumaniae y 18, como F. virguliforme. Otros ocho aislamientos no pudieron identificarse. Todos los aislamientos inoculados reprodujeron los síntomas foliares típicos de SMS. Se observaron diferencias entre el peso de mil granos de plantas sanas y de plantas enfermas y entre el rendimiento potencial y el real (p<0,05). Los daños promedio fueron de 1514 kg/ha (rango 192-3770 kg/ha). Los resultados obtenidos corroboraron la distribución y predominio de F. tucumaniae y F. viguliforme en el área estudiada y su potencial destructivo. Palabras clave: Glycine max, Fusarium tucumaniae, Fusarium virguliforme, SMS. ABSTRACT Isolation, identification and yield losses associated with sudden death syndrome in soybeans in ArgentinaThe main objectives of this work were to isolate and identify the causal agents of sudden death syndrome (SDS) from samples collected in different Argentinean localities, to quantify its incidence, and to estimate yield losses. Two hundred and fifteen roots from plants with typical SDS foliar symptoms were analyzed. In order to perform pathogenicity tests, two bioassays were conducted in the greenhouse. Yield losses were estimated in a field trial located in Pergamino by quantification and comparison of yield of paired samples. Thirty-six percent of total roots (78 roots) presented signs of Fusarium, compatible with signs caused by SDS. Morphological studies allowed the identification of 35 isolates as F. tucumaniae and 18 as F. virguliforme. Other eight isolates could not be identified. All isolates that were inoculated reproduced typical SDS foliar symptoms. Significant differences were observed between healthy and diseased plants for 1000-grain weight and between potential and real yield (p<0.05). Average yield loss was 1514 kg/ha (range 192-3770 kg/ha). These results corroborated the distribution and predominance of F. tucumaniae and F. viguliforme in the area under study and its destructive potential.

Current recommendations and novel strategies for sustainable management of soybean sudden death syndrome

“…In terms of its economic impact, SDS is considered to be one of the top 10 soybean diseases of North America 39 with average yield losses of 0.82 million metric tons per year between 1996 to 2009 40 and US$321,5 million per year between 1996 ando 2016 39 . Additionally, SDS generates significant yield losses in Argentina and Brazil, two other leading soybean‐producing countries 1,41 (Table 1).…”