First report of a leaf spot disease caused by Alternaria protenta on the Datura stramonium in Serbia.
Datura stramonium (jimsonweed) is an invasive and competitive annual weed and a potential reservoir host of pests and pathogens in agricultural fields. During a survey of potato growing fields in the municipality of Maglić, Vojvodina Province, typical Alternaria symptoms on leaves of D. stramonium were observed among the potato plants in September 2016. The incidence of diseased plants ranged from 12 to 70%. The symptoms started as small, round, light brown spots with chlorotic haloes, which gradually enlarged to 0.3 to 2 cm in diameter, becoming irregular and sometimes having a dark brown border. Based on the results of morphological observations, DNA sequencing and pathogenicity tests, the causal agent was identified as Alternaria protenta. This is thought to be the first report of A. protenta causing leaf spot on D. stramonium in Serbia.