1,720,973 research outputs found
Biological notes on Parahypopta caestrum and first microbiological control assays
No full textWe provide notes about the biology and the ethology of Parahypopta caestrum (Hubner) (Lepidoptera Cossidae), based on field
observations conducted in asparagus plantations in Apulia region, Italy. Furthermore, the effect of 6 entomopathogenic nematode
(EPN) strains (Steinernematidae and Heterorhabditidae) and 3 entomopathogenic fungal (EPF) isolates (Beauveria bassiana) was
evaluated in laboratory assays against III instar larvae of the asparagus moth. The results showed that all the nematodes and fungal
strains affected the asparagus moth survival, except the Steinernema affine and Heterorhabditis bacteriophora strains.
Steinernema feltiae and B. bassiana showed the best performances, killing on average 90% of the P. caestrum larvae. Considering
the lack of effective chemical control means, the microbiological control of the asparagus moth by EPNs and EPFs reveals promising
perspectives and needs further investigations
Prove di controllo microbiologico di insetti in habitat criptici con nematodi entomopatogeni
No full textEffect of Beauveria bassiana and Metarhizium anisopliae on the Trialeurodes vaporariorum-Encarsia formosa system
No full textThe virulence of three strains of Beauveria bassiana and one of Metarhizium anisopliae was tested against Trialeurodes vaporariorum and its parasitoid Encarsia formosa in laboratory assays. These strains were previously selected for their virulence against Galleria mellonella and Tenebrio molitor. The commercial B. bassiana strain ATCC 74040, both as pure fungal culture and formulated myco-insecticide (Naturalis), was included in the assays as positive control. First, the entomopathogenic fungal strains were tested for their virulence against T. vaporariorum nymphs on tomato leaf disks. Then, the E. formosa development was evaluated under treatment with the entomopathogenic fungal strains at five different time points from the parasitization of T. vaporariorum nymphs. The virulence of our entomopathogenic fungal strains was superior to that of ATCC 74040,although not significantly, resulting in a cumulative mortality (CM) of T. vaporariorum nymphs 7 days after inoculation (DAI) greater than 86 %. Our M. anisopliae strain CIST8 was the most effective (96.6 % CM 7 DAI), even superior to the myco-insecticide Naturalis (94.2 %), which was more effective than the ATCC 74040 pure strain (85.6 %). The entomopathogenic fungal strains, and especially Naturalis, negatively affected E. formosa development and its parasitization activity of T. vaporariorum nymphs. This effect was more pronounced when the fungal strains were applied before parasitization. Results suggest that the application of entomopathogenic fungi is incompatible with E. formosa release on crops
Effect of Beauveria bassiana strains on the Ceratitis capitata - Psyttalia concolor system
Full text linkThe effects of a previously selected entomopathogenic fungus, Beauveria bassiana AL1 strain, and the B. bassiana based myco-insecticide Naturalis (ATCC 74040 Beauveria bassiana strain) were evaluated on the system Ceratitis capitata - Psyttalia con-color in laboratory assays. First, the entomopathogenic fungal strains were tested for their virulence against 2, 4, and 6-days old puparia of C. capitata. Subsequently, P. concolor emergence from C. capitata puparia treated or not with the fungal strains was evaluated at three different time points (2, 4 and 6 days) from the parasitization and the following pupation. Results showed that the entomopathogenic fungal applications affected the medfly survival. The effect of fungal treatments was higher on 2-day pu-paria (49.16 and 51.33% of mycosed puparia for ATCC 74040 and AL1 strain respectively) while the rate of mycoses was lower and ranged between 39 and 27.16% when fungal treatments were performed on 4 and 6-day puparia. Furthermore, fungal treat-ments affected the P. concolor emergence (c.a. 80% in the untreated control) particularly when applied 2 days after the parasitiza-tion and the C. capitata pupation (43.16 and 47.83% for the ATCC 74040 and the AL1 strains respectively), while when treat-ments were performed on older puparia, the P.concolor emergence ranged from 63.33 to 68.66%. Results suggest that the ento-mopathogenic B. bassiana strains are effective against C. capitata puparia but they may be detrimental against its endoparasitoid P. concolor, particularly when applied in the earlier stages of the parasitization process
Natural enemies emerged from Thaumetopoea pityocampa (Denis & Sciffermüller) (Lepidoptera Notodontidae) pupae in Southern Italy
Full text linkObservation made over a 4-year period in pinewoods of Apulia Region (South Italy) on Thaumetopoea pityocampa (Denis Sciffermüller) (Lepidoptera: Notodontidae) prepupae and pupae, indicated the following natural enemies complex: Hexamermis sp. (Nematoda: Mermithidae), Phryxe caudata (Diptera: Tachinidae), Villa brunnea and Hemipenthes velutina (Diptera: Bombyliidae), Conomorium pityocampae (Hymenoptera: Pteromalidae), Coelichneumon rudis and Cryptus sp. (Hymenoptera: Ichneumonidae), Beauveria babiana and Isaria farinosa (formerly Paecylomices farinosus) (Ascomycota: Hypocreales). The moths and the parasitoid species emerged sequentially and, although these natural enemies show irregular distribution, they together controlled up to 60% of T. pityocampa pupae. Ecological implications of such parasitism are being discubed
Infectivity of mediterranean native entomopathogenic nematodes (Steinerne-matidae and Heterorhabditidae) from natural habitats in relation to temperature
Full text linkThe infectious activity of 15 Steinernema and Heterorhabditis strains of Entomopathogenic Nematodes (EPNs), belonging to 5 species (Steinernema feltiae, S. affine, S. apuliae, S. ichnusae and H. bacteriophora) collected from natural habitats (meadows, coasts and woods) in Southern Italy was compared in laboratory bioabays against Galleria mellonella larvae. Infectivity was determined by 2 larval mortality rate abays in relation to different temperature values. In the first experiment the percentage of larval mortality was recorded after a 72-hr exposure period to the EPNs Infective Juveniles (IJs) at 6 temperatures between 10 and 35°C, at intervals of 5°C, using IJs in aqueous suspension. The second bioabay was performed to compare the infectivity at 3 relatively low temperature values (6-10-14°C), using IJs in 2 different suspensions (aqueous and gel); the percentage of larval mortality was recorded every 72 hrs for 12 days after exposure to IJs. In the first experiment S. feltiae, S. ichnusae and S. affine strains showed the best performances at temperature values 10, 15, 20 and 25°C, while H. bacteriophora and S. apuliae showed the best results at 30 and 35°C. In the second test S. feltiae, S. ichnusae and S. affine strains demonstrated a better cold-infectivity (at 6-10-14°C) than H. bacteriophora and S. apuliae strains. IJs in the water suspension killed the Galleria larvae quicker than those in the gel. The gel suspension keeps nematodes more safe and active than the water one
Effects of entomopathogenic fungi on Encarsia formosa Gahan. (Hymenoptera: Aphelinidae) activity and behavior
No full textThe effects of a previously selected entomopathogenic fungus, Beauveria bassiana AL1 strain, and the B. bassiana-based mycoinsecticide Naturalis were evaluated on the Trialeurodes vaporariorum-Encarsia formosa system. The parasitoid's ability to recognize uninfected and infected hosts was examined by evaluation of E. formosa tropism in 'choice' conditions and its activity (residence time on leaf, searching time, handling hosts time and hosts acceptance) in no-choice conditions. Finally, the role of E. formosa in transmitting the mycoses from infected to uninfected host populations was estimated. E. formosa showed no differential tropism in 'choice' conditions. It was able neither to locate the host at distance nor to discriminate between infected and uninfected hosts. E. formosa was able to vector fungal propagules from contaminated to uncontaminated hosts during its activity. The results of these laboratory experiments have clarified some biological and behavioral aspects of pathogen-host-parasitoid interactions
Comments on the morphology and biology of Pammene castanicola Trematerra & Clausi, 2009 (Lepidoptera: Tortricidae: Grapholitini)
No full textMany insects are reported to damage cultivated chestnut (Castanea sativa Mill.; Fagaceae) in Italy, but the most
important pests of chestnut fruits are weevils (Curculio elephas Gyll. and Curculio glandium Marsh.; Curculionidae) and
tortricid moths (Pammene and Cydia; Tortricidae) (Pollini, 1998, Speranza, 1999). The larvae of the tortricid pests
develop internally, tunnelling in the fruits and eating the endocarp (Rotundo et al. 1991), which significantly reduces nut
quality and commercial value. The most damaging tortricid moths in the Italian chestnut industry are Pammene fasciana
(Linnaeus) (the early chestnut moth), Cydia fagiglandana (Zeller) (the intermediate chestnut moth), and Cydia
splendana (Hübner) (the late chestnut moth) (Pedrazzoli et al. 2012). Pammene castanicola Trematerra & Clausi, 2009
was recently described from chestnut woods near Etna Vulcan, Sicily (Trematerra and Clausi 2009), and it is known only
from the vicinity of the type locality. It is similar to Pammene fasciana in morphological and biological features, and it
was previously misidentified as P. fasciana. We provide observations on the biology and larval development and present
detailed descriptions and illustrations of the mature larva of P. castanicola, with comments on the differences between P.
castanicola and P. fasciana
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