Detection and characterization of fungus (Magnaporthe oryzae pathotype Triticum) causing wheat blast disease on rain-fed grown wheat (Triticum aestivum L.) in Zambia

• DOI: 10.1371/journal.pone.0238724
• Publication Date: 2020-09-21T17:57:05Z
• Authors: Batiseba Tembo; Rabson M. Mulenga; Suwilanji Sichilima; Kenneth K. M’siska; Moses Mwale; Patrick C. Chikoti; Pawan K. Singh; Xinyao He; Kerry F. Pedley; Gary L. Peterson; Ravi P. Singh; Hans J. Braun
• Keywords: Pyricularia; Blast disease; Spots

Wheat blast caused by Magnaporthe oryzae pathotype Triticum (MoT) is a threat to wheat production especially in the warmer-humid environments. In Zambia, symptoms were observed for first time on (Triticum aestivum L.) grown experimental plots and five farmers' fields Mpika district of Muchinga Province during 2017–18 rainy season. Infected plants showed typical with spike becoming partially or completely bleached blackening rachis short span time. Incidence nearly all heads was high ranged from 50 100%. Examination diseased plant leaves presence elliptical, grayish tan necrotic lesions dark borders leaf often mixed other foliar diseases. A study conducted isolate identify causal pathogen(s) using classical molecular methods determine pathogenicity detected disease agent. Morphobiometrical determination pathogen revealed conidia characteristic pear shaped 2-septate hyaline spores associated M. species. Preliminary polymerase chain reaction screening six isolates obtained infected samples diagnostic primers (MoT3F/R) at ZARI, subsequent analysis two MoT3F/R C17F/R performed USDA-ARS, USA. Both experiments confirmed that MoT agent Zambia. Further, tests pure culture WS4 WS5 produced inoculated genotypes. Results this indicate causing rain-fed thus making it report Zambia Africa. This inter-continental movement (disease) has serious implication trade needs be urgently addressed.