First Characterisation of the Phoma Species Complex on Maize Leaves in Central Europe.

Lucia Ramos Romero,Birger Koopmann,Dagmar Tacke,Andreas Von Tiedemann

doi:10.3390/pathogens10091216

Lucia Ramos Romero, Birger Koopmann + Show 2 more

Open Access

https://doi.org/10.3390/pathogens10091216

Copy DOI

Journal: Pathogens	Publication Date: Sep 18, 2021
Citations: 2	License type: CC BY 4.0

Affiliation: University of Göttingen

Abstract

In the last decade, the cultivated area of maize has increased in Central Europe due to its high yield potential and diverse uses for feed and bio-energy. This has led to more intense maize cultivation, with narrowed crop rotations resulting in the increase in maize leaf diseases. During 2012 and 2013, an inventory of maize leaf spot diseases was carried out in various regions in Central Europe. In addition to the major leaf pathogens, isolates of Phoma-like species were obtained from oval to elliptical spots on leaves or found in lesions produced by other leaf pathogens. A total of 16 representative Phoma-like strains were characterised for their pathogenicity on maize leaves, for their morphological characteristics and with a phylogenetic analysis based on multilocus sequence analysis using part of the actin (ACT), calmodulin (CAL), β-tubulin (TUB), internal transcribed spacer (ITS) region of ribosomal DNA and large subunit ribosomal RNA (LSU) genes. The strains were grouped into four clades, and morphological studies supported this classification for most of them. Strains were compared with six reference Phoma-like species strains from the Westerndijk Fungal Biodiversity Institute collection reported to colonise maize. The pathogenic group of strains from our collection (after completion of Koch’s postulates) did not cluster with any of these species, indicating a different and novel Phoma-like species infecting maize leaves. To our knowledge, this is the first study dissecting the Phoma species complex on maize leaves in Central Europe.

Highlights

In the last decade, the cultivated area of maize has progressively increased in Central Europe due to its high yield potential and the option of diverse uses for feed and bioenergy
A total of 16 representative Phoma-like isolates were selected for phylogenetic analysis based on multilocus sequence analysis (MLSA) using part of the actin (ACT), calmodulin (CAL), β-tubulin (TUB), internal transcribed spacer (ITS) region of ribosomal DNA and large subunit ribosomal RNA (LSU) genes
The pathogenic strains obtained in this work induced leaf spots in the greenhouse after spray inoculation, which were similar to the early symptoms found in the field and are described in the literature for the most common Phoma-like pathogen on maize leaves, D. maydis [15]

Summary

Introduction

The cultivated area of maize has progressively increased in Central Europe due to its high yield potential and the option of diverse uses for feed and bioenergy This has led to more intense maize cultivation in many regions, with narrowed crop rotations resulting in the increased presence of various maize leaf diseases such as northern corn leaf blight (Exserohilum turcicum, teleomorph Setosphaeria turcica) and eyespot (Kabatiella zeae). The genus Phoma and other related genera are known to contain a large number of pathogenic species associated with leaf, grain or stem diseases These have been shown to damage many important crops worldwide such as citrus lemon [1], sunflower [2,3], oilseed rape [4,5,6], tobacco [7], sorghum [8,9], wheat [10,11], rice [12], sugarcane [13] and coffee [14], potentially causing significant economic losses. Some Phoma species or fungi related to this genus have been reported as causal agents of diseases on leaves, stems, roots and grains of maize [15,16,17,18,19,20,21]

Objectives

Methods

Results

Conclusion