Four Common Setaria Species are Alternative Hosts for Clavibacter michiganensis subsp. nebraskensis, Causal Agent of Goss's Bacterial Wilt and Blight of Corn

Abstract

Goss's bacterial wilt and blight, caused by Clavibacter michiganensis subsp. nebraskensis (Cmn), has reemerged as an important disease of Zea mays (corn) in the U.S. Midwest. Results from a 2011 multistate survey indicated that Setaria spp. (foxtail) were often present in corn fields with a history of Cmn. The objective of this research was to determine if Setaria spp. that are common in the Midwest are susceptible to infection by Cmn. In the greenhouse, seedlings of four Setaria spp., including S. viridis (green foxtail), S. faberi (giant foxtail), S. verticillata (bristly foxtail), and S. pumila (yellow foxtail), and Zea mays (Golden Cross Bantam sweet corn, GCB) were inoculated with a suspension of 1.0 × 107 bacteria cells. The trial was arranged in a randomized complete block design and repeated once. Percent of symptomatic leaf area was visually estimated eight days after inoculation. S. faberi exhibited the highest levels of disease among the four Setaria spp., with disease incidence similar to what was observed on Z. mays. S. viridis was the next most susceptible. Symptoms were also observed on S. viridis, S. verticillata, and were lowest for S. pumila. Bacterial streaming was confirmed microscopically and Cmn was reisolated from the four Setaria species. Results indicate that these four Setaria spp. are susceptible to Cmn, thus serving as potential sources of inoculum. Accepted for publication 1 February 2014. Published 28 April 2014.

Clavibacter nebraskensis causing Goss's wilt of maize: Five decades of detaining the enemy in the New World

“…drummondii ), and eastern gamagrass ( Tripsacum dactyloides ) are reported to act as secondary hosts for C. nebraskensis (Langemeier et al, 2012 , 2014 ; Schuster, 1975 ; Webster et al, 2019 ). Furthermore, annual ryegrass ( Lolium multiflorum ), bristly foxtail, giant foxtail, green foxtail, yellow foxtail, Johnson grass ( Sorghum halepense ) and large crabgrass ( Digitaria sanguinalis ) have been reported to be hosts of C. nebraskensis based on symptom development in artificially inoculated plants (Ikley et al, 2015 ; Langemeier et al, 2014 ). The pathogen was isolated from barnyard grass ( Echinochloa crus‐galli ) although subsequent experiments failed to confirm that it could be infected (Ikley et al, 2015 ; Wysong et al, 1981 ).…”

“…Using amplified fragment length polymorphism (AFLP) analysis and repetitive DNA sequence‐based BOX‐PCR, Agarkova et al ( 2011 ) reported 131 C. nebraskensis strains collected between 1969 and 2009 clustered into two groups, A and B, where group B represents recent genetic changes between 1999 and 2009 while the genome of group A had been stable for a long period of time. Similarly, Langemeier et al ( 2012 ) used AFLP and rep‐PCR DNA to separate 466 strains collected in the United States into three main groups. No geographical basis for groupings was noted.…”

Herbicide safener isoxadifen‐ethyl associated with increased Goss's wilt severity in corn (Zea mays)

“…18 The re-emergence of Goss's wilt in the United States has been linked to factors of susceptible hybrids, higher planting populations, less diverse crop rotations, higher residue, reduced or no-tillage practices, longitude, yield history, and growth stage. 19 Glyphosate and surfactant use was also suggested to be a cause of increased plant disease. 20,21 However, follow-up research studies and reviews have indicated that there are no associations between herbicide tolerance traits, glyphosate use, and surfactant use with an increase in plant disease and Goss's wilt.…”

Goss’s Wilt Resistance in Corn Is Mediated via Salicylic Acid and Programmed Cell Death but Not Jasmonic Acid Pathways

“…In severe cases, yield reductions as high as 50% have been reported. Since there is no known effective chemical control for Cn , producers rely on tillage, clean farm equipment, and primarily good corn genetics [ 9 , 14 , 17 , 18 , 19 , 20 , 21 ]. Controlling alternative hosts such as Seteria viridis (green foxtail) may also reduce the Cn transmission to and infection of corn plants [ 17 , 22 ].…”