ABSTRACT
Worldwide, barley (Hordeum vulgare L.) is the fourth most important cereal after wheat, maize, and rice and it is used in the livestock, food, and brewing industry. The main producer of this cereal is the Russian Federation with a production of 18 million tons per year. In Mexico, the barley is planted in an approximate area of 283,386 ha; 83% of this area is located in the States of Hidalgo (44%), Mexico (11%), Puebla (14%), and Tlaxcala (14%). The cultivation conditions depend on rainfall as a unique source of moisture during the summer cycle. Unfortunately, the minimum tillage methods and monoculture 276of cereals have favored the increase of phytopathogens causing foliar spots, root rot, and fusariosis; which is particularly important because it affects yield and produces toxins in the grain that are harmful to human and animal health. Among the phytopathogenic fungi that cause losses in barley plantations worldwide, Puccinia striiformis can be mentioned that causes yellow or linear rust. Puccinia hordei that causes leaf rust or brown rust, Drechslera teres/Pyrenophora teres that causes net stain, with losses in yield greater than 50%, to the fungi Alternaria spp., Fusarium spp., Epicoccum sp., which cause the black tip, Fusarium spp., which cause fusariosis, F. graminearum/Gibberela zeae that causes seedling blight, Bipolaris sorokiniana/Cochliobolus sativus that causes seedling blight or blurred spot, Ustilago nuda that causes loose smut, and U. hordei causing covered smut disease. The yellow rust and the red spot diseases cause the greatest damage to the barley plantations. The phytopathogenic fungi classification of barley worldwide has been based on the use of morphological characters and the relationship with their hosts. Therefore, performing the morphological characterization of fungal isolates from the barley plant in Mexico will allow us to have knowledge about the microorganisms that are present in our country and thus to control those that are harmful to the plant. For that, the aim of this research was the isolate and morphological characterization of fungi associated with diseased barley plants in Mexico.
