37 research outputs found
Entomophaga maimaiga ā New entomopathogenic fungus in the Republic of Serbia
The higher mortality rate of the older gypsy moth larval instars was reported in the forest complexes of Belgrade and Valjevo region, in the culmination phase of the new outbreak of the gypsy moth in Serbia. By field and laboratory studies of the causes of their death, the presence of conidia and resting spores of the entomopathogenic fungus Entomophaga maimaiga was reported in the dead caterpillars. This has been the first report of occurrence of this species in Serbia, that is, Serbia is the third European country in which this fungus has been reported. It showed to be a powerful reducer of the population size of the gypsy moth, and in both regions it caused the collapse of the outbreak in 2011.Keywords: Entomophaga maimaiga, Lymantria dispar, gypsy moth, biological control, epizootic
Baryscapus transversalis Graham (Hymenoptera: Eulophidae) ā NOVA VRSTA U FAUNI BOSNE I HERCEGOVINE\u27
Baryscapus transversalis (Hymenoptera: Eulophidae) was established for first time as an egg hyperparasitoid of Thaumetopoea pityocampa (Lepidoptera: Notodontidae) in Bosnia and Herzegovina. It was reared from egg batches of pine processionary moth collected on Pinus nigra in the region of Boracko jezero. In laboratory conditions, 80 specimens of B. transversalis were reared during emerging period of 20 days between 3 and 22 November 2013. In the eggs of T. pityocampa, both males and females of B. transversalis developed, in sex ratio (♀♀:♂♂) 3:1.Baryscapus transversalis (Hymenoptera: Eulophidae) je determiniran kao jajni hiperparazitoid Thaumetopoea pityocampa (Lepidoptera: Notodontidae) u Bosni i Hercegovini. Uzgojen je iz jajnih legla borovog Äetnjaka prikupljenih s lokaliteta BoraÄko jezero (Konjic) i time postao nova vrsta u entomofauni Bosne i Hercegovine. U laboratorijskim uvjetima uzgojeno je 80 jedinki B. transversalis u razdoblju od 3. do 22. studenog 2013. godine. Iz jaja T. pityocampa razvili su se i mužjaci i ženke B. transversalis u odnosu (♀♀:♂♂) 3:1
PRVI NALAZ ENTOMOPHAGA MAIMAIGA (ENTOMOPHTHORALES: ENTOMOPHTHORACEAE) U POPULACIJAMA LYMANTRIA DISPAR U GRÄKOJ I REPUBLICI MAKEDONIJI
The entomopathogenic fungus Entomophaga maimaiga Humber, Shimazu & Soper (Entomophtorales: Entomophtoraceae) was found for first time in populations of gypsy moth, Lymantria dispar (L.) (Lepidoptera: Erebidae), in Greece and the Former Yugoslavian Republic of Macedonia (FYROM) after its introduction in Bulgaria in 1999. Monitoring studies were conducted in 2012 in oak stands in three sites in the Xanthi region in Greece, and in three sites in FYROM in the Prilep region. Gypsy moth larvae, predominately in fourth to sixth instar, were collected in May and June. During laboratory rearing, mortality of gypsy moth larvae collected in two sites in Greece ranged from 36.4ā89.3%. Larval mortality of L. dispar in the three sites in FYROM ranged from 16.7ā87.8%. Dead larvae were analysed under light microscopy for presence of E. maimaiga and other entomopathogens. E. maimaiga was recorded from one site in Greece (Kidaris vill.), and in all study sites in FYROM (Toplica, Belovodica and Krushevo vill.). Azygospores of E. maimaiga were found in the bodies of 78.6% of gypsy moth larvae from Kidaris, and in 8.3ā16.3% of the larvae from sites in FYROM. Recent records of E. maimaiga in Serbia and the European part of Turkey, and present findings in Greece and FYROM, indicate that the fungus most probably has invaded gypsy moth populations in other parts of Balkan Peninsula.Entomopatogena gljiva Entomophaga maimaiga Humber, Shimazu & Soper (Entomophtorales: Entomophtoraceae) prvi je puta utvrÄena u populacijama gubara, Lymantria dispar (L.) (Lepidoptera: Erebidae) u GrÄkoj i Republici Makedoniji nakon introdukcije ovog patogena u Bugarsku 1999. godine. Tijekom 2012. godine obavljen je pregled hrastovih sastojina na tri lokacije u podruÄju Xanthi u GrÄkoj i na tri lokacije u okolici Prilepa u Makedoniji. Gusjenice gubara sakupljane su veÄinom u Äetvrtom do Å”estom larvalnom stadiju u razdoblju svibanjālipanj. Tijekom laboratorijskog uzgoja smrtnost gusjenica sakupljenih u GrÄkoj iznosila je od 36,4 do 89,3 %. Smrtnost gusjenica s lokaliteta u Makedoniji bila je izmeÄu 16,7 i 87,8 %. Uginule gusjenice analizirane su pomoÄu svjetlosnog mikroskopa na prisutnost E. maimaiga i ostalih patogena. Patogena gljiva E. maimaiga utvrÄena je na uzorku s jednog lokaliteta u GrÄkoj (Kidaris) i na uzorcima svih lokaliteta u Makedoniji (Toplica, Belovodica i KruÅ”evo). Azigospore E. maimaiga utvrÄene su u 78,6 % uginulih gusjenica s lokaliteta Kidaris i izmeÄu 8,3 i 16,3 % uginulih gusjenica s tri lokaliteta u Makedoniji. Nedavni nalazi E. maimaiga u Srbiji i europskom dijelu Turske te najnoviji nalazi u GrÄkoj i Republici Makedoniji ukazuju na vjerojatnost da je ovaj patogen veÄ inficirao populacije gubara u ostalim dijelovima balkanskog poluotoka
First records of Sirococcus conigenus causing shoot blight on Pinus peuce in Bulgaria
Macedonian pine (Pinus peuce) is a southern Balkan Peninsula endemic, growing in high mountains of Bulgaria, between 1400 and 2100 m a.s.l. Stands of P. peuce form the upper tree line forest areas. During a survey in 2020-2022 on Macedonian pine natural stands and plantations in Bulgaria, symptoms of shoot blight were observed in the Pirin Mts, the Rila Mts and Mt Vitosha. The fungal pathogen Sirococcus conigenus was identified as the causal agent of the disease that appeared for the first time on Pinus peuce in Bulgaria and Balkan Peninsula. Incidence of blighted shoots on individual trees varied, but was as high as 70-80% in the Rila Mts and Mt Vitosha
A checklist and areography of the longhorn beetles (Coleoptera, Cerambycidae) of Pirin Mountains, Bulgaria
The longhorn beetles fauna of Pirin Mountains, Bulgaria, was studied, based on literature data and original material. As a result, 100 taxa from five subfamilies are listed for the area, as follows: Prioninae (7 taxa), Lepturinae (31 taxa), Spondylidinae (9 taxa), Cerambycinae (28 taxa) and Lamiinae (25 taxa).This study presents two new records for Pirin Mts. (Oxymirus cursor and Tetropium fuscum fuscum) and new localities or additional information for 13 cerambycid taxa (species and subspecies). The 100 longhorn beetle taxa belong to 17 zoogeographical categories and eight complexes. The European complex occupies a dominant position (34%), followed by those from Palaearctic (17%), Eurosiberian (15%), Mediterranean (15%), European-Iranoturanian (9%), Balkan endemic (5%) and Holarctic (4%) complexes
Damage caused by singing cicadas (Hemiptera: Cicadidae) in the field protective forest belts in South Dobrudzha, Bulgaria
During the period 2020-2023, strong damage caused by singing cicadas (Hemiptera: Cicadidae) were registered on ash trees (Fraxinus spp.) in the field protective forest belts (FPFBs) in South Dobrudzha, northeastern Bulgaria. Bioacoustic studies have shown that the sounds are of Cicada orni. Many exuvia of the species were also found on the trunks and branches of ash trees. On the upper shoots and petioles, numerous oviposition holes were observed, which lead to leaf fall and drying of branch tips. In different FPFBs, tree crown damage ranges from a moderate (25-60% defoliation) to a severe (over 60% defoliation) degree. The attacks were stronger on Fraxinus excelsior and F. americana compared to F. angustifolia. The cicadas affect both old trees and young ash saplings. In young plantations, other tree species (Sophora japonica, Gleditsia triacanthos) were also affected. Imaginal activity of Cicada orni was recorded in July and August, and the peak of egg hatching occurred from early August to mid-September. The high number of Cicada orni necessitates the development of measures to control the pest in the FPFBs
Egg parasitoids of Thaumetopoea pityocampa in the region of Gyumyurdzhinski Snezhnik in Eastern Rhodopes, Bulgaria
The region of Gyumyurdzhinski Snezhnik in the Eastern Rhodopes is the closest in Bulgaria to the Aegean Sea. However, the climate is characterized by specific parameters that are determined by its relief. It is poorly protected from the invasion of cold air masses from the north. From the south, the Gyumyurdzhinski Snezhnik hill restrains the Mediterranean influence. The orography of the area favors the retention of cold air masses and a further drop in temperatures. The experimental material for the study includes 5 generations of Thaumetopoea pityocampa (2016, 2017, 2018, 2019, and 2022), collected in 31 locations of four State Forestry Enterprises: Kirkovo, Ardino, Momchilgrad, and Zlatograd. The sample for analysis included 693 egg batches with 148420 eggs in them. Seven primary egg parasitoids were established in this region: Ooencyrtus pityocampae, Baryscapus servadeii, Pediobius bruchicida, Anastatus bifasciatus, Eupelmus vesicularis, E. vladimiri, Trichogramma sp. and one hyperparasitoid (B. transversalis). Dominant parasitoids were B. servadeii and O. pityocampae, and E. vladimiri and P. bruchicida – occasional parasitoids. The hyperparasitoid B. transversalis participated in the complex with a relatively low share. The survival of the egg parasitoids in the laboratory conditions, in which the samples were kept, was low. The total mortality of the parasitoids in larval and adult stages was 47.8%. After collecting the samples, in laboratory conditions, a total of 442 individuals of the hyperparasitoid B. transversalis emerged, of which 56.3% were females and 43.7% were males. The average number of pine processionary moth eggs in a batch was 214.2. 70.8% of all the eggs in the samples hatched successfully. The egg parasitoids are a very serious natural factor, regulating the density of the pine processionary moth, but their impact varied from 2.1% to 30.3%. The natural characteristics of the area, the air temperature during the stages of eggs and young larvae, are favorable for the development of the pine processionary moth. Unhatched larvae without the influence of entomophages were 7.2%
Monitoring of the health status of Castanea sativa in the Belasitsa mountain, southwest Bulgaria
In the period 2017-2023, a survey for the assessment of the phytosanitary condition of sweet chestnut (Castanea sativa) was conducted in a permanent sample plot (PSP) Belasitsa, which is part of the European large-scale network for monitoring the health status of forest ecosystems under the International Co-operative Program ‘Forests’. The PSP is set in a natural chestnut stand in Belasitsa mountain at an altitude of 643 m. Data collected from the first years of the monitoring determined a slight deterioration in the health status of the chestnut trees caused by an infection with the fungal pathogen Cryphonectria parasitica. An improvement in trees’ vitality and lack of active necrosis were observed in 2022-2023. On the wounds, initiation of callus along the wounded edges was reported. Currently, the introduction of new and dangerous invasive insect pests Dryocosmus kuriphilus, Corythucha arcuata, etc., has not been detected. Attacks of both pests could further deteriorate the health status of the sweet chestnut in Belasitsa
Three species of bark beetles (Coleoptera: Curculionidae, Scolytinae) on Pinus peuce in Pirin Mountains in Bulgaria
In 2020 and 2021, three species of bark beetles (Coleoptera: Curculionidae, Scolytinae) were established on Macedonian pine (Pinus peuce) in the region of Vihren hut in Pirin Mts. Branches, damaged by snow were collected and studied in laboratory conditions. As a result, 24 specimens of Ips amitinus were reared in 2020 and 81 specimens of I. amitinus, Crypturgus pusillus and Pityogenes chalcographus in 2021. The most abundant species was I. amitinus with 75.2%, followed by P. chalcographus (21.9%) and C. pusillus (2.9%)