Research on the evolution of the major pest of sycamore tree (Platanus spp.) in the bolintin deal nursery.
In 2014-2018, a study was conducted to observe the evolution of the lace bug Corythucha ciliata (Say) and the mining moth Phyllonorycter platani (Staudinger) on the sycamore tree leaves, and the soil pests as well. C. ciliata, which causes the yellowing of sycamore tree leaves, was observed in the Bolintin Deal nursery in August 2014, whose attack on the leaves was between 1.31-6.31% during August-October, with a maximum number of 45 adults and nymphs / colonized leaf. During the years 2015-2018, between April and October, the percentage of trees attacked was between a minimum of 1.58% in 2016 and a maximum of 29.17% in 2015. P. platani on the sycamore tree were also reported in 2014. There were observed leaves with characteristic symptoms (more or less oval, subeliptical forms mines) and leaves with obvious discoloured areas (with the upper edges arched and the lower and crested lower cuticle). The sycamore mine moth is part of the group of invasive species of Lepidoptera Gracilariidae which have an obvious economic and/or ecological effect and have expanded in Europe over the last 20 years. The mining moth was present from April to October. The mines formed in October and November are larger and evident on the leaves, often several mines on the same leaf. In 2014, during the August-October period, out of the total of the leaves attacked, 41.38% presented only one mine/leaf, 6.9% two mines/leaf, 17.24% three mines/leaf and 34.48% five mines/leaf. In the following years the percentage of mines per leaf was between 14.1% for 5 mines/leaf and 46.1% for 1 mine/leaf. As regards the soil fauna, the main groups of soil pests (wire worms, white worms and grey worms) were evaluated. The numerical density of larvae was somewhat uniform, and the populations of wire Worms are predominant.