Drosophila suzukii Matsumura (Diptera: Drosophilidae) is an invasive polyphagous species, that is frequently found in blackberry culture, affecting the commercial value of fruits. Between 2020-2021, ...in the blackberry collection of the University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca (Romania), were carried out observations on susceptibility of five cultivated varieties (‘Thornless’, ‘Loch Ness’, ‘Thornfree’, ‘Thornless Evergreen’ and ‘Navaho’) to D. suzukii. In 2020, the attack frequency in the whole collection was 78.2%. ‘Thornfree’ had the highest attack frequency, 89% while ‘Loch Ness’ was the least susceptible with a frequency of attack of 71%. In 2021, the overall proportion of damaged fruits in the collection was 59.6%. The most susceptible was ‘Thornless’ with an attack frequency of 66% and ‘Thornless Evergreen’ with only 49%. The incidence of infestation by the spotted-wing Drosophila suzukii is influenced by the thermal characteristics of the year, with temperatures higher than 30 °C impacting the fertility of females and the viability of eggs. In the year 2020, the average number of larvae per fruit collected was 6.4, while the average number of larvae in the ‘Loch Ness’ cultivar was 9.4, with a maximum of 48 larvae per fruit. In 2021, an average of 3.4 larvae per fruit were observed, with variations ranging from 2.8 larvae in the ‘Thornfree’ cultivar to 4.2 larvae in the ‘Navaho’ cultivar.
In Europe, the box tree moth, Cydalima perspectalis (Walker, 1859) was first reported in 2006, in southwestern Germany, then spread to almost all countries. Larvae of this species affect the ...aesthetic value of the box tree. In the last period, numerous studies were carried out regarding the identification of useful entomofauna that reduce the numerical density of the population of Cydalima perspectalis. In this study conducted in north-western Romania (Cluj County, in 2019), entomopathogens and useful entomofauna were monitored in four areas, represented by four cities. The entomopathogenic agents contaminated the larvae of the box tree moth in a proportion of 5.6% at Gherla, 6.8% at Dej, 8.7% at Cluj-Napoca and 15.3% at Ciucea. Most larvae have been infected with Bacillus. At Cluj-Napoca and Ciucea, the presence of the larval endoparasite Exorista larvarum L. (Diptera: Tachinidae) was reported. Parasitoid species determined a parasitization rate of 5.1% at Dej, 8.6% at Gherla and 13.4% at Cluj-Napoca. Predators affected pupae in a proportion of 3.8% at Gherla, 4.2% at Dej and 16% at Cluj-Napoca. Among the pupae predators, for the first-time common earwig was reported, Forficula auricularia L. Entomopathogenic agents affected 5.3% of the pupae collected from Cluj-Napoca, 7.7% in Gherla and 12.5% in Dej. During the monitoring period of the zoophagous entomofauna and the entomopathogenic microorganisms, affected the pupae in a percentage of 20.1% in Gherla, 21.8% in Dej, 34.7% in Cluj-Napoca, contributing to the diminution of the population of the harmful species.
The most important pests of acacia black locust (Robinia pseudoacacia L.) (Fabaceae) are: Appendiseta robiniae Gillette, Phyllonorycter robiniella Clemens, Parectopa robiniella Clemens, Nematus ...tibialis Newman and Obolodiplosis robiniae Haldemann, species from North America, where it also originates the acacia, which is the host plant. In Europe these species were introduced accidentally, being considered invasive species. In Europe, O. robiniae Haldemann was first reported in July 2003 in northeastern Italy, in Paese near Padua, from where it spread to almost the entire European continent, especially through trade in infested biological material from nurseries. The attack occurs in the species R. pseudoacacia L., R. viscosa L. and R. hispida L., mainly in urban areas, where it mainly affects their aesthetic value. The larvae develop characteristic leaf margin roll galls on the infested leaves. There are up to 6 galels on a leaflet, and on average there are up to 5-6 larvae. In Europe it develops two, three and, in optimal conditions, even four generations a year. Zoophagous entomofauna can cause population decline, especially parasitoid species. For Platygaster robiniae Buhl & Duso (Hymenoptera: Platygastridae) the percentage of parasites reported was up to 40%. A low percentage of parasitism can be produced by other species, such as: Aprostocetus sp., Chrysocharis sp. (Hymenoptera: Eulophidae), Eupelmus urozonus Dalman (Hymenoptera: Eupelmidae), Eurytoma verticillata F. (Hymenoptera: Eurytomidae), Mesopolobus mediterraneus Mayr. (Hymenoptera: Pteromalidae) and Torymus sp (Hymenoptera: Torymidae).
The species of pear sucker, also called pear psylla or pear psyllid, which are destructive insects belonging to the genus Cacopsylla (Hemiptera: Psyllidae) cause substantial damage to pear tree ...plantations. Two consecutive years of research were conducted on the population structure and biological cycle of psylla in a small, elderly, and unmaintained pear orchard in northern Romania. Of the two identified species (C. pyri L. and C. pyricola Forster), C. pyri dominated the psylla population with a percentage of 77.8-80.1%. Adults of both species emerge from hibernation in the first part of March and produce three generations per year. First-generation adults emerge in the first decade of June, the second generation in the last decade of July, and the third generation in the first decade of September as they enter the hibernation phase. Larvae of the first generation appear in the second half of April, the second generation at the end of June - the beginning of July, and the third generation in the second decade of August. There have been reports of up to 11 adults and 27 larvae per leaf, 9 larvae per petiole, and 14 larvae per fruit. The number of adults captured on yellow sticky traps exposed on the southern side of the tree crown was significantly higher compared to the northern side. Following the intense attack, the well-known cv. ‘Williams’ was heavily affected, pear trees were badly defoliated, blackened, and aged prematurely. The climatic conditions of the two years did not influence the phenology of the pests, but the importance of monitoring psyllids is widely argued, considering that it remains the key to integrated protection programs in pear orchards.
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