Orlando Campolo | Mediterranean University of Reggio Calabria (original) (raw)

Papers by Orlando Campolo

Horticulturae, 2022

The control strategies for the olive crop key pest, Bactrocera oleae, involve synthetic chemical ... more The control strategies for the olive crop key pest, Bactrocera oleae, involve synthetic chemical insecticides and few eco-sustainable alternatives, such as ovideterrents and lures. In the last few decades, the interest concerning the formulation of botanical based biopesticides increased, but little research investigated the suitability of these approaches for B. oleae control. This research aimed to investigate the residual contact toxicity and the oviposition deterrence of three essential oil (EO)-based nano-emulsions (Pimpinella anisum, Foeniculum vulgare, Mentha × piperita) against B. oleae adult flies. All the nano-emulsions possessed optimal physical characteristics, with droplets dimensions ranging from 115 to 152 nm and low PDI values (<0.2), even after 1 year of storage. Although no notable residual contact toxicity was noted, all the tested formulations reduced the number of oviposition puncture in no-choice tests (percent repellence: mint < fennel < anise). In ch...

Common control strategies to manage stored product pests are mainly based on the use of synthetic... more Common control strategies to manage stored product pests are mainly based on the use of synthetic insecticides and fumigants. Consumer's demand for pesticide-free food, and the increasing resistance of pests to traditional insecticides, dictate the need to evaluate alternative control methods. For this purpose, many sustainable techniques have been tested for the control of stored product pests. Among them, Citrus essential oils can represent a valid alternative to synthetic insecticides. The effects of Sweet Orange essential oil (EO) nanoemulsion applied as cold aerosol were evaluated against adults of Tribolium confusum du Val (Coleoptera: Tenebrionidae) and Cryptolestes ferrugineus Stephens (Coleoptera: Cucujidae). Both chemical and physical characterization of the EO-based formulation was carried out. The developed formulation had an average size belonging to the nanometer scale and a low polydispersity index. The relatively high zeta potential value confirms the stability o...

Molecules, 2021

The family Tephritidae (Diptera) includes species that are highly invasive and harmful to crops. ... more The family Tephritidae (Diptera) includes species that are highly invasive and harmful to crops. Due to globalization, international trade, and human displacement, their spread is continuously increasing. Unfortunately, the control of tephritid flies is still closely linked to the use of synthetic insecticides, which are responsible for detrimental effects on the environment and human health. Recently, research is looking for alternative and more eco-friendly tools to be adopted in Integrated Pest Management (IPM) programs. In this regard, essential oils (EOs) and their main compounds represent a promising alternative to chemical insecticides. EOs are made up of phytoconstituents formed from the secondary metabolism of many plants and can act as attractants or toxics, depending on the dose. Because of this unique characteristic, EOs and their main constituents are promising tools that can be used both in Sterile Insect Technique (SIT) programs and in the “lure and kill” technique, e...

Sustainability, 2021

Post-harvest pest control can rely on few approved pesticides and tools; hence, there is a rising... more Post-harvest pest control can rely on few approved pesticides and tools; hence, there is a rising interest in new sustainable, eco-friendly approaches. In this study, eight commercial essential oils (EOs) (anise Pimpinella anisum, artemisia Artemisia vulgaris, fennel Foenicum vulgare, garlic Allium sativum, lavender Lavandula angustifolia, mint Mentha piperita, rosemary Rosmarinus officinalis, and sage Salvia officinalis) were selected for their bioactivity and commercial availability, and then formulated in nano-emulsions. Repellency and acute toxicity of the developed nano-formulations were tested against a key stored product pest, Tribolium confusum (Coleoptera: Tenebrionidae). All the developed nano-emulsions presented optimal physical characteristics (droplet dimension = 95.01–144.30 nm; PDI = 0.146–0.248). All the formulations were repellent over time tested against adult beetles, in area preference bioassays. The best repellent was the anise EO-based formulation (RC50 = 0.033...

Insects, 2021

The development of biologically based approaches for stored product pest control is needed to red... more The development of biologically based approaches for stored product pest control is needed to reduce chemical inputs. Bioassays were performed to investigate host habitat location in the trophic interaction durum wheat/Rhyzopertha dominica/Theocolax elegans. GC-MS analyses were carried out to identify some chemical compounds produced by the host-related substrates. Choice and no-choice experiments demonstrated that female parasitoids were poorly attracted to intact kernels with respect to the infested substrates. Furthermore, T. elegans females performed longer residence time on infested wheat, and they generally displayed a short-term like fidelity for this cue, remaining on it during the whole observation. Infested wheat emitted one chemical (fenchone), which is possibly linked to host larvae presence, while the feces produced by host larvae emitted some other characteristic compounds. Results demonstrated that the presence of host larvae is a key factor for T. elegans host habita...

Industrial Crops and Products, 2020

Essential oils (EOs) are promising active ingredients for biopesticides, although their use under... more Essential oils (EOs) are promising active ingredients for biopesticides, although their use under field conditions is limited by several criticisms concerning their high volatility and degradability. To overcome these negative qualities, EOs can be encapsulated inside nanostructures (i.e. nanoparticles and nano-emulsions), which can guarantee the preservation of the insecticidal properties. In the current study, oil in water (O/W) nano-emulsions of seven commercial EOs (15 % w/w of anise, artemisia, fennel, lavender, peppermint, rosemary, sage) were developed using different non-ionic surfactants and formulation processes, to identify the best possible surfactant/process to produce stable nano-formulations. The EOs were firstly examined by gas-chromatography analyses to identify their chemical constituents. Sage, rosemary, peppermint, lavender and artemisia EOs were characterized by high percentage (up to 50 % of the detected compounds) of oxygenated monoterpenes, while fennel and anise EOs were mainly constituted by phenylpropenes (e.g. anethol). Then, nano-emulsions were developed via the self-emulsifying process alone or in combination with sonication, using four surfactants with different Hydrophilic Lipophilic Balance (HLB) index (5 % w/w of Tween 20, Tween 80, Span 20 or Span 80). The physical characteristics (droplet size and surface charge) of nano-emulsions were analyzed using the dynamic light-scattering technique. Sonicated nano-formulations presented smaller and more homogeneous size of the micelles than the non-sonicated ones, resulting in more stable nano-emulsions. Furthermore, usually emulsions produced using Tween 80 as surfactant gave the best results in terms of droplet size and polydispersity index (PDI) values. Therefore, Tween 80 sonicated nano-emulsions were examined during a storage period of 28 weeks to determine their stability over time and possible alteration of their physical characteristics. Results suggest that these nano-formulations had a good stability over time, since relatively small increases in PDI and size values were recorded. Formulation stability is a key issue to consider when proposing botanical biopesticides for agricultural applications. Our study reports the first step in the introduction of EO-based nano-emulsions into practical application.

Industrial Crops and Products, 2021

Abstract Essential oils (EOs) are promising active ingredients to produce biopesticides, although... more Abstract Essential oils (EOs) are promising active ingredients to produce biopesticides, although their physicochemical characteristics are a critical issue to develop commercial formulates. Repellent and toxic activity of EOs against crop and stored product pests has been widely investigated in the last decades; however, no information is available on the occurrence of adverse undesirable behavioral responses (i.e. habituation) toward these repellents in target pest species. In this study, stable EO-based nano-emulsions from commercial fennel (Foeniculum vulgare), mint (Mentha x piperita) and sweet orange (Citrus sinensis) EOs were developed, and their repellence was tested against a major stored product pest, the lesser grain borer Rhyzopetha dominica. Besides, the occurrence of habituation in R. dominica adults following successive exposure to the repellent formulations was evaluated, considering the main characteristics of this kind of non-associative learning. Nanometric droplet size was achieved for all developed nano-emulsions (

Scientific Reports, 2020

Plant nutritional quality and chemical characteristics may affect the fitness of phytophagous ins... more Plant nutritional quality and chemical characteristics may affect the fitness of phytophagous insects. Here, the olfactory preferences of Bactrocera oleae (Rossi) females toward olives with different maturation and infestation status were evaluated in three cultivars: Ottobratica, Roggianella and Sinopolese. Volatile profiles from olives were identified by SPME/GC-MS. Choice tests were performed to determine the responses of B. oleae adult females toward fruits and pure chemicals linked to infestation degree. Cultivar was the main source of variability explaining the differences recorded in volatile emissions. Moreover, three VOCs [β-myrcene, limonene and (E)-β-ocimene] were associated to infestation status across all olive varieties. In choice-tests, B. oleae females always preferred the olfactory cues from low-infested over high-infested fruits. Therefore, choice-tests using synthetic VOCs, emitted in greater amount by high-infested fruit, were arranged in order to identify putati...

Industrial Crops and Products, 2019

Control strategies in stored-product facilities mainly rely on synthetic pesticides. The developm... more Control strategies in stored-product facilities mainly rely on synthetic pesticides. The development of new environmentally friendly alternatives, such as essential oils (EOs), is a key issue. The aim of this research was to develop a stable nano-emulsion containing a high amount of sweet orange (Citrus sinensis) EO and to evaluate its insecticidal activity against Tribolium confusum du Val (Coloptera: Tenebrionidae) and Cryptolestes ferrugineus (Stephens) (Coleoptera: Cucujidae). The experimental nano-emulsion showed a low surface charge (ζ slightly higher than −30 mV) and a droplet size within the sub-micrometre range (131.37 nm ± 0.29), maintained also after 1 year of storage. The EO nano-emulsion presented good repellence toward both adult insects, which lasted until 24 h of exposure at the highest dosages. Furthermore, the developed nano-formulation showed acute toxicity against both insects when tested as fumigant and cold aerosol. In fumigation trials, adults of C. ferrugineus were more susceptible than T. confusum adults. Moreover, the insecticidal activity of cold aerosol was 5 and 7-fold higher than fumigation against both C. ferrugineus and T. confusum, respectively. The EO-nanoemulsion was effective in controlling and repelling the target pests. Cold aerosol treatments with EO nanoformulations is a promising alternative method for the sanitation of production areas, warehouses, and machineries.

Entomologia Generalis, 2018

The black soldier fly, Hermetia illucens L. (Diptera: Stratiomyidae) is a promising species used ... more The black soldier fly, Hermetia illucens L. (Diptera: Stratiomyidae) is a promising species used as protein source for aquaculture and zootechnical diets, which has been also proposed as biological tool for managing organic wastes. Here, we investigated the courtship and mating behaviour of H. illucens, recording the behavioural sequences displayed, the occurrence of same-sex interactions and the role of female-borne signals eliciting male courtship. The sequence of events leading to successful copulation is not dissimilar from other stratiomyid species, although H. illucens females were able to convey their preferences for mates according to male courtship behaviours. Males performed wing fanning during courtship prior to move backwards on the female body. Once the males mounted the females, they tapped the female abdomen with the tarsi of its second and third pairs of legs and attempted to accomplish preliminary genital contacts. Male wing fanning during mounting attempts seemed pivotal for female acceptance. Same-sex courtship behaviours were observed among males, which were not able to distinguish between males and females during the in-flight approach and the mounting attempt. Wing fanning played a key role also in evoking behavioural responses of males. Indeed, the males just approached conspecifics beating their wings during flight, while no courtship was recorded toward females that did not perform wing beating. This study improves the knowledge about sexual behaviour of H. illucens, highlighting the role of wing fanning among the range of sensory modalities used in the sexual communication of stratiomyid flies.

Journal of Pest Science, 2019

The South American tomato pinworm, Tuta absoluta, is considered worldwide as one of the most impo... more The South American tomato pinworm, Tuta absoluta, is considered worldwide as one of the most important tomato pests. Insecticide resistance reported on the moth and the awareness about the negative impact of agrochemicals on the environment and human health have raised the demand for new control tools. Among these, RNA interference (RNAi) can represent a valid tool to be included into new control strategies against this pest. Here we report the results of trials aimed at evaluating the effects of dsRNAs targeting acetylcholinesterase (AChE), nicotinic acetylcholine alpha 6 (nAChRs), ryanodine (RyRs) receptors by injection and root delivery. In the injection procedure, 2 and 5 µg of dsRNA were able to reduce the gene expression in a range of 62.7-75.4%, inducing a maximum mortality rate of 92.59%. The dsRNAs administered at 5 µg by root absorption revealed the potential of this delivery system to affect the gene expression (47-69% reduction) and the mortality (ranging from 67.1 to 80.5%) of treated specimens. The delivered dsRNAs (both injected and root administered) affected the weight of both T. absoluta pre-pupae and pupae. The selected AChE, nAChRs and RyRs genes can be suitable targets for T. absoluta control by means of in planta delivery dsRNAs.

Journal of Food Quality, 2018

Among botanical extracts used as insecticides, essential oils (EOs) are promising alternatives to... more Among botanical extracts used as insecticides, essential oils (EOs) are promising alternatives to chemical insecticides. EOs are synthesized by plants, and they play a key role in plant signaling processes including also attractiveness toward pollinators and beneficial insects. Plant species producing essential oils (over 17,000 species) are called aromatic plants and are distributed worldwide. Our review aims to evaluate research studies published in the last 15 years concerning the use of EOs in stored product protection. More than 50% of the retrieved manuscripts have been published by authors from Eastern countries (Iran, China, India, and Pakistan), investigating different aspects related to insect pest management (exposure route, effect on the target pest, and mode of action). Coleoptera was the most studied insect order (85.41%) followed by Lepidoptera (11.49%), whereas few studies targeted new emerging pests (e.g., Psocoptera). Almost all the trials were carried out under la...

Scientific reports, Feb 1, 2018

Olfaction is a pivotal sense for insects and granivorous pests may exploit grain volatiles for fo... more Olfaction is a pivotal sense for insects and granivorous pests may exploit grain volatiles for food selection. Tribolium confusum, is a secondary pest of stored cereals that benefits from primary pests' infestation, as other secondary feeders, triggering competition. This study aimed to evaluate the preferences of T. confusum females toward different-infested paddy rice, highlighting the impact of intra- and interspecific competition. Tribolium confusum showed positive chemotaxis toward rice infested by larvae of a primary pest (Sitophilus zeamais), but not for grain attacked by adults alone. Furthermore, kernels concurrently infested by a primary (S. zeamais) and a secondary pest (T. confusum or Cryptolestes ferrugineus) were evaluated in Y-tube bioassays, highlighting that both food-sources were innately attractive for T. confusum females. Moreover, females positively oriented toward rice infested by conspecifics, while they avoided grain infested by C. ferrugineus, averting a...

PloS one, 2018

Microorganisms are acknowledged for their role in shaping insects' evolution, life history an... more Microorganisms are acknowledged for their role in shaping insects' evolution, life history and ecology. Previous studies have shown that microbial communities harbored within insects vary through ontogenetic development and among insects feeding on different host-plant species. In this study, we characterized the bacterial microbiota of the highly polyphagous Mediterranean fruit fly, Ceratitis capitata (Diptera: Tephritidae), at different instars and when feeding on different host-plant species. Our results show that the bacterial microbiota hosted within the Mediterranean fruit fly differs among instars and host-plant species. Most of the bacteria harbored by the Mediterranean fruit fly belong to the phylum Proteobacteria, including genera of Alphaproteobacteria such as Acetobacter and Gluconobacter; Betaprotobacteria such as Burkholderia and Gammaproteobacteria such as Pseudomonas.

Scientific reports, Jan 12, 2017

The repeated use of conventional synthetic pesticides in crop protection leads to resistance deve... more The repeated use of conventional synthetic pesticides in crop protection leads to resistance development by pests along with a negative impact on the environment, particularly non-target arthropods. Plant-derived active compounds, such as essential oils (EOs), play a key role in sustainably controlling pests. The lethal and sublethal activity of citrus peel EOs as emulsions and included in polyethylene glycol (PEG) nanoparticles (EO-NPs) was determined against the invasive tomato pest Tuta absoluta. Their effects on the plants were also assessed. The results showed an overall good insecticidal activity of the compounds tested, with a higher mortality through contact on eggs and larvae by EO emulsions and through ingestion on larvae by EO-NPs. The nanoformulation also significantly reduced the visible toxic effects on the plants. The data collected suggest that these natural compounds, especially when nanoformulated, could be successfully used in integrated pest management programs f...

Entomologia Generalis, 2017

The parasitization of honeybees by Varroa destructor represents a serious limiting factor for bee... more The parasitization of honeybees by Varroa destructor represents a serious limiting factor for beekeeping. The past and current widespread use of synthetic acaricides, such as fluvalinate and coumaphos, results in the onset of pest resistance, therefore research efforts focused on the use of alternative solutions to control the population of this parasitic mite. In the present study, the efficacy of two formulates containing Oxalic Acid (OA) or Formic Acid (FA) was evaluated in real field conditions. Our results demonstrated the effectiveness of the OA formulate in controlling more than 90% of V. destructor phoretic population. On the other hand, FA shown an efficacy of 60% on phoretic mites. A similar pattern was highlighted on brood and adult bees' infestation. The OA formulate showed a proper efficacy, highlighting its potential as alternative to chemical substances in holding the increase of V. destructor during a late summer treatment.

Microbial Ecology, 2017

Microbial communities associated to the gut of insects are attracting an increasing interest, mai... more Microbial communities associated to the gut of insects are attracting an increasing interest, mainly because of their role in influencing several host life-traits. The characterization of the gut microbial community is pivotal for understanding insect ecology and, thus, to develop novel pest management strategies. The pine processionary moth, Thaumetopoea pytiocampa (Denis & Schiff.) (Lepidoptera: Thaumetopoeidae), is a severe defoliator of pine forests, able to feed on several pine species. In this work, we performed a metabarcoding analysis to investigate, for the first time, the diversity of the gut bacterial community of pine processionary larvae associated with three different host pine species (Pinus halepensis, Pinus nigra subsp. laricio, and Pinus pinaster). We found that t he gut microbial community of T. pityocampa larvae collected on P. halapensis was different from that associated with larvae collected from P. nigra and P. pinaster. Moreover, the high presence of bacteria belonging to the genera Modestobacter, Delftia, and unidentified Methylobacteriaceae retrieved in larvae feeding on P. halapensis suggested that specific interactions can occur. Our results provide the evidence that different host plant differently impact on the microbiota diversity of T. pityocampa larvae, contributing to the general knowledge of this pest with information that could be useful in shaping the next generation of pest control strategies.

Open Life Sciences, 2017

RNA interference (RNAi) is a powerful strategy for gene function analysis, and it is also widely ... more RNA interference (RNAi) is a powerful strategy for gene function analysis, and it is also widely studied in view of a promising use in pest control. The red palm weevil, Rhynchophorus ferrugineus (Oliver) (Coleoptera: Curculionidae), is one of the most devastating pests of palm in the world. Conventional pest management practices are not adequate to control this insect, thus the development of efficient approaches with minimal environmental impact are needed. In this work, the potential of RNAi in R. ferrugineus has been investigated through the silencing of three different genes (α-amylase, V-ATPase, Ecdysone receptor). For each gene we tested two different doses (1,500 and 5,500 ng) and two delivery techniques (injection and ingestion), evaluating both gene knockdown and mortality on insects. Results show that RNAi mediated gene silencing in R. ferrugineus varies from gene to gene, and that the response is dose-dependent, with stronger effects when dsRNA was administered by inject...