EFFECTS OF NATURAL COMPOUNDS FROM Citrus limon (L.) Burm. f. ON THE BEHAVIOR OF Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) AND Grapholita molesta (Busck) (Lepidoptera: Tortricidae)

Effetti di composti naturali da Citrus limon (L.) Burm. f. sul comportamento di Ceratitis capitata (Wiedemann) e Grapholita molesta (Busck). La ricerca ha riguardato gli effetti che le sostanze naturali provenienti da Citrus limon (L.) Burm. f. hanno sul comportamento di due importanti fitofagi dei fruttiferi, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) e Grapholita molesta (Busck) (Lepidoptera: Tortricidae). Inizialmente si è proceduto all’estrazione di differenti sostanze dal flavedo di quattro cultivar di limone coltivate in Sicilia; in particolare sono stati estratti gli oli essenziali e grazie a tre solventi organici (etere di petrolio, diclorometano e metanolo) sono stati ottenuti tre differenti estratti per ciascuna cultivar. Le sostanze volatili ottenute (oli essenziali) sono state saggiate sulle antenne della mosca mediterranea della frutta, mentre gli estratti sono stati saggiati sui tarsi dello stesso insetto; in entrambi i casi la risposta elettrofisiologica è stata registrata nei laboratori del prof. Antonio De Cristofaro dell’Università del Molise. Inoltre sono state condotte prove elettroantennografiche su α-terpineolo, geranil acetato e citrale, composti presenti nei frutti di C. limon. I menzionati estratti delle cultivar Lunario e Interdonato sono stati utilizzati per prove comportamentali di laboratorio volte all’individuazione del comportamento indotto su C. capitata; in queste prove femmine adulte del dittero provenienti da allevamenti in insettario avevano la possibilità di scegliere e ovideporre su sfere trattate o meno con gli estratti. Per gli oli essenziali sono stati individuati i componenti e loro quantità; poiché era già nota una loro attività repellente, per quelli di due cultivar sono state approntate delle prove di campo in un aranceto biologico. Nelle prove sperimentali, per la prima volta è stato dimostrato che quasi tutte le sostanze saggiate suscitano una risposta elettrofisiologica, mostrando quindi la loro percezione da parte della mosca mediterranea della frutta. In particolare per quanto riguarda gli estratti di Lunario e Interdonato, cinque su sei hanno mostrato una significativa attività repellente e antiovideponente aprendo nuove prospettive sui prodotti di possibile utilizzo vi in pieno campo, soprattutto nei frutteti biologici dove non è permesso l’utilizzo di composti sintetici. E’ interessante notare anche l’innovazione nella metodologia degli studi comportamentali in laboratorio, che per la prima volta hanno visto l’utilizzo di sfere inerti, ma forate, quindi adatte a valutare l’attività dei composti sull’ovideposizione. Degli oli essenziali saggiati negli aranceti, quelli della cultivar Lunario si sono dimostrati efficaci nel ridurre l’infestazione di C. capitata su arance a maturazione precoce, cv. Navelina, indicando con ciò che si è molto vicini alla formulazione di un preparato da utilizzare in campo nel prossimo futuro. Un’altra parte del progetto portata avanti durante il dottorato di ricerca è stata svolta in Canada nei laboratori del dott. Robert Mitch Trimble, Agriculture and Agri-Food Canada di Vineland Station (Ontario). Qui si è sviluppata una tematica legata all’applicazione dei feromoni sessuali dei lepidotteri tortricidi; in particolare si è studiato l’effetto del citrale, composto comune a molti frutti di Citrus spp., su G. molesta, importante lepidottero fitofago del pesco e altre rosacee. Sono state condotte delle prove di adattamento sensoriale al citrale e al feromone, sulle antenne dei maschi mediante analisi elettrofisiologiche, e su maschi adulti in tunnel del vento. In entrambi i casi si è utilizzato il “piezo-electric microsprayer” che permette il rilascio di quantità note di sostanze volatili, e nel caso dei feromoni tale rilascio è molto vicino alle modalità di emissione delle femmine vergini. E’ stata messa in luce per la prima volta la capacità del citrale di stimolare le antenne dei maschi, esaltare la percezione del feromone sessuale e quindi di avere un effetto sinergico a causa del processo di adattamento sensoriale; nelle prove di comportamento si è anche evidenziata la capacità del citrale di ostacolare l’aggancio della scia feromonale da parte del maschio. Ciò potrebbe permettere un utilizzo del citrale in pieno campo nella tecnica della confusione sessuale da solo o in sinergia con il più costoso feromone

Biological activity of Citrus spp. metabolites on Ceratitis capitata (Wiedemann).

The Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), is one of the most injurious pest at global level. During the last years, several electrophysiological and behavioural studies have been carried out in order to investigate plant volatile compound-insect interactions with the aim to use this knowledge in sustainable control techniques. It has been observed that lemons are not attacked by medfly, probably because of the peel oil, that is toxic to other fruit flies. In the present paper electrophysiological recordings were conducted to evaluate the insect sensitivity to peel extract and peel oil of two Sicilian cultivars (Interdonato and Lunario) of Citrus x limon (L.) Burm.f. on C. capitata females. Behavioural bioassays were also performed to show their possible biological activity (repellent, antioviposition, insecticidal). C. limon peel extracts in different solvents (petroleum ether, dichloromethane and methanol) were investigated at various concentrations using a single cell recording technique (stimulation of tarsal taste chemosensilla). Different tarsal taste cell responses to the two cultivars were recorded. The higher sensitivity was evoked by C. limon Interdonato, particularly to the methanol extract, which elicited significant increases in the spike frequency at increasing concentrations. The peel oil of the same cultivars as well as that ones of other two C. limon varieties (Monachello and Femminello) have been tested by EAG techniques. The EAG data showed a high sensitivity (about -8.0/8.5mV) of the medfly antennae to the oils of Citrus spp. and a clear dose-response relationship. Responses of adult females (virgin and mated) to Citrus spp. peel extract were quantified in a double-choice test using yellow spheres (diameter 7.0cm) housed in field cages. Preliminary tests conducted on three extracts of C. limon Interdonato and Lunario have provided interesting results. It was recorded a general decrease of the oviposition on treated spheres compared to control and in the case of the cultivar Lunario, a mortality of insects

First data on the repellent activity of essential oils of Citrus limon towards medfly (Ceratitis capitata)

The biological activity of peel essential oils of two Sicilian cultivars of C. limon, ‘Interdonato’ and ‘Lunario’, was investigated by electrophysiological recordings (EAG) and field trials on Ceratitis capitata (Wiedemann) (Diptera Tephritidae). The EAG data showed a remarkable dose-response relationship and a low activation threshold dose (10-3M) for both essential oil extracts. In field tests, essential oils showed a good repellent and antiovipositional activi- ty on ‘Navelina’ oranges, and in particular the essential oils of ‘Lunario’ pro- vided the same results of kaolin. Potential applications of essential oils from C. limon cultivars against C. capitata in organic farming are discussed

Biological activity of metabolites extracted from Citrus spp. on Ceratitis capitata (Wiedemann) (Diptera: Tephritidae)

The Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), is one of the most injurious pest at global level. During the last years, several electrophysiological and behavioural studies have been carried out in order to investigate plant volatile compound-insect interactions with the aim to use this knowledge in sustainable control techniques. It has been observed that lemons are not attacked by medfly, probably because of the peel oil, that is toxic to other fruit flies. In the present paper electrophysiological recordings were conducted to evaluate the insect sensitivity to peel extract and peel oil of two Sicilian cultivars (Interdonato and Lunario) of Citrus x limon (L.) Burm.f. on C. capitata females. Behavioural bioassays were also performed to show their possible biological activity (repellent, antioviposition, insecticidal). C. limon peel extracts in different solvents (petroleum ether, dichloromethane and methanol) were investigated at various concentrations using a single cell recording technique (stimulation of tarsal taste chemosensilla). Different tarsal taste cell responses to the two cultivars were recorded. The higher sensitivity was evoked by C. limon Interdonato, particularly to the methanol extract, which elicited significant increases in the spike frequency at increasing concentrations. The peel oil of the same cultivars as well as that ones of other two C. limon varieties (Monachello and Femminello) have been tested by EAG techniques. The EAG data showed a high sensitivity (about -8.0/8.5mV) of the medfly antennae to the oils of Citrus spp. and a clear dose-response relationship. Responses of adult females (virgin and mated) to Citrus spp. peel extract were quantified in a double-choice test using yellow spheres (diameter 7.0cm) housed in field cages. Preliminary tests conducted on three extracts of C. limon Interdonato and Lunario have provided interesting results. It was recorded a general decrease of the oviposition on treated spheres compared to control and in the case of the cultivar Lunario, a mortality of insects

Electrophysiological and Behavioral Responses of Oriental Fruit Moth to the Monoterpenoid Citral Alone and in Combination With Sex Pheromone

The monoterpenoid citral synergized the electroantennogram (EAG) response of male Grapholita molesta (Busck) antennae to its main pheromone compound Z8 Ð12:OAc. The response to a 10-g pheromone stimulus increased by 32, 45, 54, 71 and 94% with the addition of 0.1, 1, 10, 100 and 1,000 g of citral, respectively. There was no detectable response to 0.1, 1, or 10 g of citral; the response to 100 and 1,000 g of citral was 31 and 79% of the response to 10 g of Z8 Ð12:OAc. In a ßight tunnel, citral affected the mate-seeking behavior of males. There was a 66% reduction in the number of males orientating by ßight to a virgin calling female when citral was emitted at 1,000 ng/min 1 cm downwind from a female. Pheromone and citral induced sensory adaptation in male antennae, but citral did not synergize the effect of pheromone. The exposure of antennae to 1 ng Z8Ð12:OAc/m3 air, 1 ng citral/m3 air, 1 ng Z8 Ð12:OAc 1 ng citral/m3 air, or to 1 ng Z8 Ð12:OAc 100 ng citral/m3 air for 15 min resulted in a similar reduction in EAG response of 47Ð63%. The exposure of males to these same treatments for 15 min had no effect on their ability to orientate to a virgin calling female in a ßight tunnel. The potential for using citral to control G. molesta by mating disruption is discusse

Sensory Adaptation of Antennae and Sex Pheromone-Mediated Flight Behavior in Male Oriental Fruit Moths (Leptidoptera: Tortricidae) After Prolonged Exposure to Single and Tertiary Blends of Synthetic Sex Pheromone

Sensory adaptation has been measured in the antennae of male Grapholita molesta (Busck) after 15 min of exposure to its main pheromone compound (Z)-8-dodecen-1-yl acetate (Z8-12:OAc) at the aerial concentration of 1 ng/m(3) measured in orchards treated with pheromone for mating disruption. Exposing males to this aerial concentration of Z8-12:OAc for 15 min, however, had only a small effect on their ability to orientate by flight to virgin calling females in a flight tunnel. Experiments were undertaken to determine if exposure to the main pheromone compound in combination with the two biologically active minor compounds of this species, (E)-8-dodecen-1-yl acetate (E8-12:OAc) and (Z)-8-dodecen-1-ol (Z8-12:OH) would induce greater levels of sensory adaptation and have a greater effect on male sexual behavior. The exposure of male antennae to 0.5 g/m(3) air of one of the three pheromone compounds induced sensory adaptation to this compound and to the other two pheromone compounds demonstrating cross adaptation. Average percentage sensory adaptation to a pheromone compound was similar after 15 min of exposure to 1 ng/m(3) air of Z8-12:OAc, or to 1 ng/m(3) air of a 1:1:1 or 93:6:1 blend of Z8-12:OAc, E8-12:OAc, and Z8-12:OH. The exposure of males to 1 ng/m(3) air of Z8-12:OAc or the two ratios of Z8-12:OAc, E8-12:OAc, and Z8-12:OH for 15 min had no effect on their ability to orientate to a virgin calling female. The implications of these results for the operative mechanisms of sex pheromone-mediated mating disruption of this species are discussed

Indole Alkaloids from Psychoactive Mushrooms: Chemical and Pharmacological Potential as Psychotherapeutic Agents

Neuropsychiatric diseases such as depression, anxiety, and post-traumatic stress represent a substantial long-term challenge for the global health systems because of their rising prevalence, uncertain neuropathology, and lack of effective pharmacological treatments. The approved existing studies constitute a piece of strong evidence whereby psychiatric drugs have shown to have unpleasant side effects and reduction of sustained tolerability, impacting patients’ quality of life. Thus, the implementation of innovative strategies and alternative sources of bioactive molecules for the search for neuropsychiatric agents are required to guarantee the success of more effective drug candidates. Psychotherapeutic use of indole alkaloids derived from magic mushrooms has shown great interest and potential as an alternative to the synthetic drugs currently used on the market. The focus on indole alkaloids is linked to their rich history, their use as pharmaceuticals, and their broad range of biological properties, collectively underscoring the indole heterocycle as significant in drug discovery. In this review, we aim to report the physicochemical and pharmacological characteristics of indole alkaloids, particularly those derived from magic mushrooms, highlighting the promising application of such active ingredients as safe and effective therapeutic agents for the treatment of neuropsychiatric disorders

Indole Alkaloids from Psychoactive Mushrooms: Chemical and Pharmacological Potential as Psychotherapeutic Agents

Neuropsychiatric diseases such as depression, anxiety, and post-traumatic stress represent a substantial long-term challenge for the global health systems because of their rising prevalence, uncertain neuropathology, and lack of effective pharmacological treatments. The approved existing studies constitute a piece of strong evidence whereby psychiatric drugs have shown to have unpleasant side effects and reduction of sustained tolerability, impacting patients’ quality of life. Thus, the implementation of innovative strategies and alternative sources of bioactive molecules for the search for neuropsychiatric agents are required to guarantee the success of more effective drug candidates. Psychotherapeutic use of indole alkaloids derived from magic mushrooms has shown great interest and potential as an alternative to the synthetic drugs currently used on the market. The focus on indole alkaloids is linked to their rich history, their use as pharmaceuticals, and their broad range of biological properties, collectively underscoring the indole heterocycle as significant in drug discovery. In this review, we aim to report the physicochemical and pharmacological characteristics of indole alkaloids, particularly those derived from magic mushrooms, highlighting the promising application of such active ingredients as safe and effective therapeutic agents for the treatment of neuropsychiatric disorders

Preliminary Evaluation of a Granite Rock Dust Product for Pest Herbivore Management in Field Conditions

The effects of granite rock dust in dry and aqueous formulations were evaluated under field conditions for control of insect pests in different crop systems and ornamental plants. We tested efficacy of crop protection following foliar applications on lily, squash, and cabbage plants by evaluating subsequent pest damage, overall plant health, and quantity of crops produced over one season. Lily plants treated with dry and aqueous formulations of rock dust were subject to lower herbivore damage (>1% and 11% herbivory damage, respectively) when compared to the controls (30% herbivory damage). Treatment on cabbage was less effective to protect plants against herbivory damage, and no statistically significant differences were reported within treatments. The foliar applications (dry and aqueous formulations) had positive impacts on growth of squash fruit resulting in a 2.5-fold increase in size relative to the control squash fruit. These results support the potential field application of granite dust to protect ornamental plants against herbivory attack, and reveal an alternative positive effect of the silica-based product on plant growth and development

Novel β-Cyclodextrin and Catnip Essential Oil Inclusion Complex and Its Tick Repellent Properties

Cyclodextrin inclusion complexes have been successfully used to encapsulate essential oils, improving their physicochemical properties and pharmacological effects. Besides being well-known for its effects on cats and other felines, catnip (Nepeta cataria) essential oil demonstrates repellency against blood-feeding pests such as mosquitoes. This study evaluates the tick repellency of catnip oil alone and encapsulated in β-cyclodextrin, prepared using the co-precipitation method at a 1:1 molar ratio. The physicochemical properties of this inclusion complex were characterized using GC-FID for encapsulation efficiency and yield and SPME/GC-MS for volatile emission. Qualitative assessment of complex formation was done by UV-Vis, FT-IR, 1H NMR, and SEM analyses. Catnip oil at 5% (v/v) demonstrated significant tick repellency over time, being comparable to DEET as used in commercial products. The prepared [catnip: β-CD] inclusion complex exerted significant tick repellency at lower concentration of the essential oil (equivalent of 1% v/v). The inclusion complex showed that the release of the active ingredient was consistent after 6 h, which could improve the effective repellent duration. These results demonstrated the effective tick repellent activity of catnip essential oil and the successful synthesis of the inclusion complex, suggesting that β-CDs are promising carriers to improve catnip oil properties and to expand its use in repellent formulations for tick management