Search results for "Bactrocera"
showing 10 items of 22 documents
Molecular analysis of the fungal microbiome associated with the olive fruit fly Bactrocera oleae
2015
Abstract A molecular approach was used to investigate the fungal microbiome associated with Bactrocera oleae a major key pest of Olea europea , using the ITS2 region of the ribosomal DNA (rDNA) as barcode gene. Amplicons were cloned and a representative number of sequenced fragments were used as barcode genes for the identification of fungi. The analysis of the detected sequence types (STs) enabled the identification of a total of 34 phylotypes which were associated with 10 fungal species, 3 species complexes and 8 genera. Three phylotypes remained unresolved within the order Saccharomycetales and the phylum Ascomycota because of the lack of closely related sequences in GenBank. Cladosporiu…
The effect of distance between parasitoid and host on the parasitism of Psyttalia concolor (Szépligeti) in organic olive orchards
2013
Bactrocera oleae (Rossi) is a major pest of olive fruits. Biological control of olive fruit fly mainly relies on the activity of the Braconid species Psyttalia concolor (Szépligeti), which parasitizes Bactrocera oleae at the larval stage. Parasitism tests have been carried out at the insect growing facility (insectariums) of the Mediterranean Agronomic Institute of Bari (C.I.H.E.A.M.). The critical point of the use of P. concolor as a biological control agent in organic olive crop is the assessment of its effectiveness against B. oleae. Its lower presence in fruits of cultivated olives rather than in small fruits of wild olives suggests an influence of the size of the fruit, and of the thic…
È possibile il biologico per le olive da mensa?
2017
La frontiera dell’olivicoltura biologica da mensa passa attraverso il controllo della mosca delle olive in aree pandacie a forte pressione del dittero. In queste aree è di grande ausilio l’irrigazione, che facendo raggiungere prima la pezzatura desiderata, consente di sfuggire in parte alle più dannose infestazioni d’inizio autunno; in assenza d’irrigazione, spesso le drupe, all’arrivo delle piogge, aumentano in volume insieme alle infestazioni. I mezzi di controllo suggeriti sono quasi totalmente volti a evitare l’attacco, mediante l’uccisione degli adulti (catture massali o “attract and kill”) o la repellenza (argille e composti del rame); se si esclude l’uccisione delle larve di prima …
Olive seed wasps (Hymenoptera: Chalcidoidea), potentially important pests of olive crops in the Western Cape of South Africa
2019
Most phytophagous insects on cultivated olives, Olea europaea L. subsp. europaea var. europaea, in South Africa are native and come from the local wild olive tree, Olea europaea subsp. cuspidata. This paper presents the first qualitative and comparative data regarding the phytophagous seed wasps on cultivated and wild olives. From 2009 to 2012, 62 random fruit samples were collected from untreated cultivated olive trees and 53 random fruit samples from wild olives at 13 different localities in the Western Cape. During spring 2013 and summer 2014, olives collected from the trees were dissected with a scalpel (when the pit was still soft) in search of seed wasp eggs and young larvae or cut wi…
Quanta infestazione di mosca possiamo tollerare?
2022
In questo articolo sono riportati i sorprendenti risultati dei pochi recenti articoli scientifici che indicano la soglia di tolleranza della mosca delle olive per l'ottenimento di olio. In caso di raccolte precoci e medie, con estrazione entro le 24 ore, si possono ottenere oli extravergini d'altà qualità anche con 43-44% di fori d'uscita di Bactrocera oleae This article reports the surprising results of the few recent scientific papers that indicate the tolerance threshold of olive fly for obtaining oil. In case of early and medium harvests, with extraction within 24 hours, high quality extra virgin olive oils can be obtained even with 43-44% exit holes of Bactrocera oleae
Il controllo degli insetti fitofagi nell'olivicoltura biologica.
2016
Puntuali strategie di controllo, campionamenti personalizzati e maggiore consapevolezza entomologica, insita nell’approccio del coltivatore biologico, consentono ottimi risultati quali-quantitativi ed economici nella difesa fitosanitaria in olivicoltura “organica” e in qualsiasi area olivicola italiana. Le minori spese fitosanitarie rispetto all’olivicoltura convenzionale inducono un sempre maggior numero di produttori alla conversione verso il bio. Gli autori illustrano le metodologie ammesse e consigliabili in regime di agricoltura biologica, per il controllo dei principali insetti fitofagi del olivo nel Mediterraneo, con particolare riferimento alla mosca delle oilve, Bactrocera oleae, e…
Control of Bactrocera oleae by low environmental impact methods: NPC methodology to evaluate the efficacy of lure-and-kill method and copper hydroxid…
2011
The NonParametric Combination (NPC) methodology is proposed to verify the influence of the lure-and-kill method, using Ecotraps (Vioryl SA), on the distribution of Bactrocera oleae (Rossi) (Diptera Tephritidae) infestation in olive groves, and the integration of this method with copper hydroxide sprayings. This approach does not require the verification of any rigid assumption as many parametric methods do. Results of field trials indicate a strict relationship among the efficiency of the lure-and-kill method on time, dimension of the field, and population density of the olive fly. Moreover, the lure-and-kill method alone seems insufficient to provide an efficient control of the olive fly p…
Insecticidal Activity of Strains of Bacillus thuringiensis on Larvae and Adults of Bactrocera oleae Gmelin (Dipt. Tephritidae)
1999
The olive fly, Bactrocera oleae, is the key pest on olives in the Mediterranean area. The pest can destroy, in some cases, up to 70% of the olive production. Its control relies mainly on chemical treatments, sometimes applied by aircraft over vast areas, with their subsequent ecological and toxicological side effects. Bacillus thuringiensis is a spore-forming soil bacterium which produces a protein crystal toxic to some insects, including the orders of Lepidoptera, Diptera, and Coleoptera and other invertebrates. The aim of this study was to search for isolates toxic to B. oleae. Several hundred B. thuringiensis isolates were obtained from olive groves and olive presses in different areas o…
Relation of fruit color, elongation, hardness, and volume to the infestation of olive cultivars by the olive fruit fly, Bactrocera oleae
2012
The susceptibility of olive cultivars to the olive fruit fly, Bactrocera oleae (Rossi) (Diptera: Tephritidae), has seldom been studied. This article examines factors associated with olive fruit fly infestation of 16 commonly planted Sicilian olive cultivars. Total infestation data were simultaneously correlated with categorical and quantitative factors using ordinal logistic regression. When all factors were included in the analysis, year, sampling date, cultivar, and fruit color were highly significant, but the quantitative factors fruit volume, fruit elongation, and fruit hardness were not. When the analysis was repeated excluding cultivar, all quantitative factors were significant, and e…
Distribution, frequency and diversity of Bacillus thuringiensis in olive tree environments in Spain
1997
Summary Bacillus thuringiensis was isolated from samples collected from olive tree related habitats (olive groves, olive storage facilities and oil mills) of different olive producing regions in Spain. This bacterium was found in a high percentage (92%) of samples. From 72 samples analysed, 2244 sporulating colonies were selected and observed under phase contrast microscopy. From these, 414 colonies (18%) were classified as B. thuringiensis based on the production of parasporal crystals. A great variability of spore, crystal size and morphology was observed. The results indicate that olive groves are as rich as soil olive mills and olive storage facilities regarding the B. thuringiensis pop…