Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

First report of stalk rot of maize caused by Stenocarpella maydis in Spain.

Abstract

Scattered maize (Zea mays) plants with symptoms of premature wilting and leaf senescence were observed in one commercial field in Torres de Alcanadre (Huesca) during the summer of 2012. Similar symptoms including disintegrated stalk pith tissues, and lodged plants following rain and strong wind were observed again in two commercial fields in Almacelles (Lleida) in 2016 and in two commercial fields in Biota (Zaragoza) in 2017. Estimated disease incidence ranged from 15 to 30% depending on the field. Symptomatic plants were barren. Four symptomatic plants were collected from each of two fields (one in Almacelles and another in Biota) for pathogen isolation and identification. Based on morphological characteristics, molecular data (sequence analysis of the ribosomal DNA (rDNA) region consisting of the 5.8S rDNA and internal transcribed spacers 1 and 2) and pathogenicity tests, the causal agent was identified as Stenocarpella maydis. This pathogen frequently causes stalk rot of maize in the United States. However, this is thought to be the first report on S. maydis-caused stalk rot in maize in Spain. Because S. maydis is also capable of infecting grain and may produce mycotoxins, continued monitoring of this pathogen in Spain is necessary to avoid loss of yield and reduced grain quality.