В. В. Антоненко The research was carried out on the premises of the experimental study farm of Russian State Agrarian University - Moscow Timiryazev Agricultural Academy in Moscow in 2018-2019. Over two years, the authors collected and microscoped samples of affected plants of different families to determine the causative agents of fungal diseases. The identification of the fungi species of the Alternaria genus was carried out by morphological features of conidia and the habitus of sporulation. It was found that the damage of apple and pear trees is caused by two non-specialized fungus species of Alternaria tenuissima and Alternaria infectoria. It was found that 73% of 110 apple varieties and 47.2% of 53 pear varieties studied were affected to varying degrees by the fungi of the Alternaria genus. The paper describes apple varieties that have been damaged by Alternaria. There has been detected a high malware of Alternaria blight on the young seedlings of pome crops. The species of A. tenuissima and A. infectoria pathogens have been determined to affect dicotyledonous weed plants widely distributed in fruit gardens, as well as a number of garden-protective and ornamental crops. Also, their possible role as infection reservoirs and vectors for fruit crops has been established. The authors considered grade vulnerability to Alternaria blight lesion of different pome and stone fruit varieties. The most Alternaria blight-resistant varieties of pome crops have been identified. The authors have stated the relationship between the degree of Alternaria blight progression and factors such as pest damage and the location of plantings. They also describe some differences in the manifestation of Alternaria blight symptoms on apple and pear trees during the initial period of disease progression. As a result of the studies, recommendations are given on the implementation of protective measures aimed at reducing the spread of Alternaria blight of pome crops in fruit gardens.
Научная статья 
fruit trees