Lasiodiplodia regiae: a new species causing canker and dieback of fruit trees in China
Fungal diseases causing canker and dieback of fruit trees can cause serious economic losses in commercial orchards. In China, studies on trunk diseases were carried out from 2019 to 2021 in the Henan province. Ten orchards of various fruit tree species were surveyed and symptomatic samples were analyzed in the laboratory for the presence of fungal pathogens. As a result, 150 isolates of Botryosphaeriaceae were obtained from Actinidia chinensis (kiwifruit), Juglans regia (walnut), Prunus persica (peach), Prunus pseudocerasus (Chinese sour cherry), Vitis vinifera (grapevine), and Ziziphus jujuba (jujube). Affected trees showed symptoms of stem canker, branch dieback and gummosis. Morphological examination and phylogenetic analysis revealed the presence of Botryosphaeria dothidea and of a new species, Lasiodiplodia regiae sp. nov. This new species was found in A. chinensis, J. regia, P. persica, P. pseudocerasus, V. vinifera and Z. jujuba, from 4 locations in Henan. Pathogenicity tests showed that L. regiae can cause canker, dieback and gummosis in 4 studied hosts (J. regia, P. persica, P. pseudocerasus, V. vinifera). The authors noted that although B. dothidea was the dominant pathogen in the studied orchards in Henan, L. regiae was more common in orchards located in the warmer central and southern areas, and that L. regiae was not only more virulent than B. dothidea but also had a wider host range. It is concluded that further research is needed on this emerging pathogen to better understand its biology and develop control strategies.
Sources
Wang Y, Xie S, Cao J, Zhao H, Yin X, Guo Y, Xu C, Guo L, Wu H, Zhang M (2023) Lasiodiplodia regiae sp. nov.: a new species causing canker and dieback of fruit trees in China. Phytopathology 113(7), 1210-1221.