Detection of Cochliobolus heterostrophus races in South China

Abstract

Cochliobolus heterostrophus is the causal pathogen of the southern corn leaf blight (SCLB). There are three known races: race O, race C and race T. To determine which C. heterostrophus races comprise the field population in southern China and to assess diversity of these strains in terms of virulence, 200 isolates from diseased plants were collected in nine provinces/municipalities. All were race O, that is, no race T or race C isolates were found. Sixty race O isolates that sporulated well were chosen for further analysis. Virulence was measured using the integral optical density (IOD) of leaf lesions on four maize inbred lines. UPGMA cluster analysis of AFLP markers was applied to the 60 race O isolates plus control race O, T and C strains. Phylogenetic distribution, geographic location and virulence were not correlated. These results can provide valuable information for guidance in early warning and disease control.

Etiology and Symptoms of Maize Leaf Spot Caused by Bipolaris spp. in Sichuan, China

“…Previous studies have shown that the virulence of B. maydis and B. zeicola isolates is diversified and that these species have different pathotypes [13,42,44,45]. It was reported that race 3 of B. zeicola might be a mountain ecotype, favoring high humidity and cool temperature in mountain areas at high elevations [42,[46][47][48][49].…”

“…Therefore, considering these results and the lesion types of our maize samples, most isolates of B. zeicola in Sichuan Province may belong to race 3. B. maydis is generally subdivided into four races, namely, O, T, C, and S, and among them, race O is the predominant pathogen of maize in China and the disease characterized by the appearance of elongated or fusiform lesions on the leaves of susceptible plants [44,45,50,51]. We inferred that isolates of B. maydis in Sichuan may mostly belong to race O.…”

Single-cell level transcriptome of the maize pathogenic fungicochliobolus heterostrophusrace O in infection reveal the virulence related genes, and potential circRNA effector

“…The C. heterostrophus race O strains DY and WF were collected from previously identified C. heterostrophus race O library(3). A GFP coding region, GPDH promoter, and TrpC terminator were joined and constructed into a pCAMBIAth1300 plasmid(S6 Fig.)…”

“…The infection of C. heterostrophus and integral optical density (IOD) calculation were performed as described(3). SPSS 19.0 was used to analyze the significant variations among the IOD values of differential infection.…”

“…Southern corn leaf blight (SCLB), which is caused by Cochliobolus heterostrophus ( C. heterostrophus ), is a major fungal disease on maize worldwide(1, 2) (3) (4). T-toxin is the lethal effector which target on URF13 of T-cytoplasmic male-sterile(TCMS) maize line (5),(6),(7).…”