Abstract

CAZAL-MARTINEZ, Cinthia Carolina et al. Evaluation of synthetic hexaploid wheats for resistance to Wheat Blast disease. Rev. mex. fitopatol [online]. 2019, vol.37, n.1, pp.35-49.  Epub Aug 21, 2020. ISSN 2007-8080.  https://doi.org/10.18781/r.mex.fit.1807-5.

Wheat Blast disease is caused by the fungus Pyricularia oryzae pathotype Triticum. The disease has been endemic to tropical South American region for over 30 years until 2016, when it occurred in Bangladesh, opening the possibility of its expansion to other regions. Considering the limited availability of known sources of resistance in wheat and the synthetic hexaploid wheats are known to be a source of resistance to multiple type of stresses, the objective of this research was to evaluate a collection of synthetic hexaploid wheats for their resistance to Wheat Blast. The experiments were carried out in the Hernando Bertoni Research Center, Paraguayan Institute of Agricultural Technology, Paraguay. Test spikes were inoculated, concentration of 5.104 conidios.mL-1. The reaction was evaluated 15 days after inoculation and observed for next 15 days to calculate the disease-progress. Sixty-four synthetic hexaploid wheats, provided by the International Maize and Wheat Improvement Center, Mexico, were subjected to infections by isolate (P14ATae039) of P. oryzae, 18 materials were selected based on their maximum values of reaction, to be reevaluated with two different isolates P14ATae039 and P14YTae031. TS29, TS49 synthetic wheat were identified as new sources of resistance to wheat blast and TS73 wheat that is moderately susceptible, but of different genetic origin. To our best knowledge, this is the first report of synthetic hexaploid wheats selected as new sources of genetic resistance to wheat blast disease.

Keywords : Fungal disease; resistance to pathogen; Aegilops tauschii; Triticum durum.