Abstract
In Hungary, from the beginning of the 19th century, horse-chestnut trees have been planted widely and are popular ornamental trees in public parks, along streets, and in gardens. In the summer of 2015, longitudinal cracks on the trunk and branches and the intensive oozing of brown liquid were observed from a wound in a horse-chestnut tree in a park in Budapest. Some years later, in 2018 and 2019, the same symptoms were found in trees in other locations in Budapest. Several bacteria were reported that induce similar symptoms, including cracks and cankers on the bark of trunks and branches and sticky, white, red, brown, or black oozing. These pathogens belong to the genera Brenneria and Lonsdalea. Bark and exudate samples were taken with the aim of identifying the causal agent by conventional and molecular methods. Our results confirmed that the bacteria isolated from Aesculus hippocastanum trees belong to the genus Brenneria and phylogenetic analysis of the 16S rRNA gene region proved to have the closest phylogenetic relation with the Brenneria nigrifluens strains.
Highlights
Received: 27 December 2021The horse chestnut was previously mentioned as one of the most significant urban trees in the cities of Hungary [1]
In 2015 and since, vertical cracks were observed on the trunks and branches of Aesculus hippocastanum trees in Budapest
From these cracks and pruning wounds, brown-coloured, watery liquid has been oozing in humid and warm conditions (Figure 1). These symptoms were similar to those caused by bacteria isolated from willow (Brenneria salicis), walnut, plane (B. nigrifluens), and poplar (Lonsdalea populi) trees in Hungary [16,22,53]
Summary
The horse chestnut was previously mentioned as one of the most significant urban trees in the cities of Hungary [1]. The purpose was to provide food for wild animals during autumn and winter without incurring any damage to oak regrowth caused by them—big game often causes severe damage when looking for food. In these forests, such game can no longer find the feed it previously had in its natural forest stands (primarily acorn and beechnut), with which they stabilized themselves before the harsh winter [3,4]. Experts very often have a negative attitude toward forests that have
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call