Skip to main content
ARS Home » Southeast Area » Stuttgart, Arkansas » Dale Bumpers National Rice Research Center » Research » Publications at this Location » Publication #326961
Title: Survey and identification of panicle blanking bacteria in Arkansas

Author
item MULAW, TEMU - University Of Arkansas
item WAMISHE, YESHI - University Of Arkansas
item Jia, Yulin
item GEBREMARIAM, TIBEBU - University Of Arkansas
item BELMAR, SCOTT - University Of Arkansas
item KELSEY, CHRISTY - University Of Arkansas

Submitted to: Rice Technical Working Group Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 3/25/2016
Publication Date: 7/2/2017
Citation: Mulaw, T., Wamishe, Y., Jia, Y., Gebremariam, T.A., Belmar, S.B., Kelsey, C.D. 2017. Survey and identification of panicle blanking bacteria in Arkansas. Proc. 36th Rice Technical Working Group Meeting Proceedings, Galveston, TX. pg. 91-92. March 1-4, 2016. CDROM.

Interpretive Summary:

Technical Abstract: Outbreaks of bacterial panicle blight (BPB) of rice in recent past years have resulted in severe yield losses in the Southern United States including Arkansas. Bacterial species, Burkholderia glumae was identified as the main causative agent among others causing BPB in rice. The symptoms of BPB include sheath rot, panicle blighting, panicle blanking, seed discoloration and significant yield loss. Despite its economic importance, the bacteria causing BPB are poorly understood compared to other important plant pathogenic bacteria due to limited research on BPB. The major objective of this study was to collect and evaluate samples of fully or partially blanked rice panicles using cultural and molecular approaches and to identify the Burkholderia species that may have been associated with the panicle blanking in Arkansas counties in 2015. About 165 rice panicle samples that either showed some level of blanking or brown floret discoloration were collected from ten rice growing counties in Arkansas. Seeds were plated on a semi-selective medium CCNT at 38°C for 48 h and isolates were purified based on morphological characteristics of B. glumae. DNA was extracted from each pure isolate for molecular identification primarily using B. glumae specific primers. Of 165 field samples collected, 72 (44%) were considered positive for B. glumae visually on CCNT culture medium. However, the molecular approach, using specific primers, confirmed that only 45 (27%) of the diseased rice panicle samples were attributed to B. glumae. All 72 isolates were also tested for B. gladioli using specific primers. However, none tested positive to B. gladioli indicating that B. gladioli is not the major causal agent of BPB disease of rice in Arkansas. Based on this study, 73 percent of the samples were tested negative for B. glumae suggesting other causes of panicle blanking and discoloration. Results also suggested the use of the molecular technique complements visual and cultural identification of B. glumae. Overall, this study underlines the importance of molecular technique to increasing accuracy and dependability of disease identification from field samples where symptoms can be caused by different environmental and biological factors.