Abstract

MARISCAL-AMARO, Luis A. et al. Mycoflora associated to leaf spots and blights in wheat (Triticum aestivum L.) under irrigation conditions in El Bajío, Mexico. Agrociencia [online]. 2017, vol.51, n.2, pp.189-200. ISSN 2521-9766.

The production of wheat (Triticum aestivum L.) under irrigation in the Bajio region, Mexico, is mainly affected by leaf rust (Puccinia triticina Eriks.) and stripe rust (Puccinia striiformis f. sp. tritici). In recent years, other symptoms were observed in this region, such as leaf spots and blights, which also limit the productivity of the wheat varieties. In order to identify the fungi associated with these symptoms, leaves with blights and leaf spots were collected from 13 municipalities in the States of Guanajuato, Michoacan and Jalisco, Mexico, during the fall-winter agricultural cycles of 2012-2013 and 2013-2014. The fungi identification was carried out using morphological methods, amplification and sequencing of internal transcribed spacer regions (ITS). The identified pathogenic fungi were: Bipolaris sorokiniana (Sacc.) Shoem. (Synonym: Helminthosporium sativum Pammel, CM King and Bakke), Alternaria alternata (Fr.:Fr), Septoria tritici, Fusarium proliferatum (Matsushima) Nirenberg, F. equiseti (Corda) Sacc., F. moniliforme (J. Sheld) (Syn. F. verticillioides (Sacc.) Nirenberg), Curvularia spp., Cladosporium spp., the saprophytes Nigrospora spp., Torula spp., Epicoccum spp., and the antagonist fungus Chaetomium globosum Kunze ex. Fr. Although the phytopathogenic fungi frequency was low in both crop cycles, its existence in this region is a potential risk, as these fungi affect the foliage, and, if the grain is contaminated, it can rot when stored, or cause the root and stem rot when the seed is used for planting.

Keywords : Bipolaris sorokiniana; Helminthosporium sativum; Alternaria alternata; Septoria tritici; Fusarium proliferatum; Fusarium moniliforme.