Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

First report of wilt and necrosis caused by Diplodia seriata on cowpea in Tennessee, USA.

Abstract

Cowpea (Vigna unguiculata) is a productive vegetable, grain, forage or cover crop legume that is particularly adapted to subtropical and tropical climates where stresses such as drought, high temperature and marginal soil conditions are common. In 2014, several genotypes of surface-sterilised cowpea seeds were grown in a greenhouse at the University of Tennessee, Knoxville (Tennessee, USA), and after eight weeks, plants showed signs of wilting and necrosis of stems and leaves in concurrence with dark fungal growth. Based on morphological characteristics, molecular data (performed with genomic DNA of fungal mycelia, PCR amplification of internal transcribed spacer regions, followed by amplicon sequencing) and pathogenicity assays, the causal agent was identified as Diplodia seriata. This is thought to be the first report of infection of cowpea by D. seriata.