Daniela Lupi

Partial removal of water before freezing: cultivar and pre-treatments as quality factors of frozen muskmelon (Cucumis melo, cv reticulatus Naud.)

Abstract The influence of both the cultivar and the dehydration method, applied before freezing, on quality characteristics of dehydrofrozen muskmelon spheres has been studied. Water was removed from muskmelon cultivar Mirado and Rony, prior to freezing, by Dewatering–Impregnation–Soaking in concentrated solution (DIS) for 1 h, air dehydration and combined DIS-air dehydration to a final 50% weight reduction. The results of the analysis of exudate loss, texture, colour, aroma composition and sensory characteristics ascertained the crucial importance of the cultivar which had a great influence on the quality of the end products. Moisture reduction prior to freezing reduced exudate loss and improved texture at thawing. All the pre-treatments caused the loss of ethyl esters, namely “positive” aroma compounds, while the alcohols, “negative” aroma compounds, increased in air dehydrated fruits and remained stable in the DIS-treated ones. This finding could explain the higher sensory acceptability of the DIS-treated fruit when compared with those pre-air dehydrated.

Characterization of the Bacterial Community Associated with Larvae and Adults of Anoplophora chinensis Collected in Italy by Culture and Culture-Independent Methods

The wood-boring beetle Anoplophora chinensis Forster, native to China, has recently spread to North America and Europe causing serious damage to ornamental and forest trees. The gut microbial community associated with these xylophagous beetles is of interest for potential biotechnological applications in lignocellulose degradation and development of pest-control measures. In this study the gut bacterial community of larvae and adults of A. chinensis, collected from different host trees in North Italy, was investigated by both culture and culture-independent methods. Larvae and adults harboured a moderately diverse bacterial community, dominated by Proteobacteria, Actinobacteria, and Firmicutes. The gammaproteobacterial family Enterobacteriaceae (genera Gibbsiella, Enterobacter, Raoultella, and Klebsiella) was the best represented. The abundance of such bacteria in the insect gut is likely due to the various metabolic abilities of Enterobacteriaceae, including fermentation of carbohydrates derived from lignocellulose degradation and contribution to nitrogen intake by nitrogen-fixing activity. In addition, bacteria previously shown to have some lignocellulose-degrading activity were detected at a relatively low level in the gut. These bacteria possibly act synergistically with endogenous and fungal enzymes in lignocellulose breakdown. The detection of actinobacterial symbionts could be explained by a possible role in the detoxification of secondary plant metabolites and/or protection against pathogens.

A 3 year field survey of the natural enemies of the horse-chestnut leaf miner Cameraria ohridella in Lombardy, Italy

A survey to inventory the natural enemies of the horse-chestnut leafmining moth, Cameraria ohridella Deschka and Dimic (Lepidoptera, Gracillariidae) and to evaluate their relative abundance, was conducted from 2001 through 2003 in Lombardy, northern Italy. Two predators and 10 parasitoids were found during the 3-year survey. An increasing number of parasitoid species associated with the leafminer was detected (4 species in 2001, 5 in the 2002 and 10 in 2003). Eulophidae (Hymenoptera: Chalcidoidea) were most represented: Minotetrastichus frontalis Nees, Closterocerus trifasciatus Westwood, Pnigalio pectinicornis L., Pnigalio agraules Walker, Pediobius saulius Walker, Chrysocharis pentheus Walker, Cirrospilus talitzkii Bouček, Sympiesis sericeicornis Nees, Baryscapus nigroviolaceus (Nees). Only one Ichneumonidae (Hymenoptera: Ichneumonoidea) was found during 2003: Itoplectis alternans (Grav.).

Exotic Insects in Italy: An Overview on Their Environmental Impact

Hundreds of alien arthropods, native to different continents or introduced from other parts of Europe, have been recorded in Italy in the last few decades (Jucker et al., 2009; Pellizzari & Dalla Monta, 1997; Pellizzari et al., 2005). Italy is at high risk of introduction of exotic insects, particularly because of the country’s climatic conditions, which support many subtropical species, and its position in the middle of the Mediterranean Sea, which makes Italy a commercial and tourist crossroad. Invasion is a normal ecological process, but it can be incentivized by human activities with processes far more rapid than those that occur in purely native systems. Biological invasion by exotic species is considered one of the main threats to the loss of biodiversity; it can cause enormous damage in terms of socio-economic costs, harm human health, and result in ecological losses (Kenis et al., 2009). The rise in economic costs can be attributed to yield losses, in agriculture and horticulture, or to increases in the production costs for pest management. The severe economic impact of these species is evident: the crudest estimate of the total known monetary impact of alien species in Europe is close to 10 billion euros annually (COM, 2008). Moreover, the damage to human health leads to major costs connected to control programs and public health measures. Damage is due to irritation and disease transmission by hematophagous species, or to allergies, and other maladies by other groups of insects. The introduction of a species affects the ecosystem of the new habitat in different ways: the invasive species can be a herbivore, predator, or parasitoid, and can compete with indigenous species via different interactions (competition, disease transmission, hybridization). The major pathways of arthropod migration are indeed accidental, represented by different means of transports, the trade in ornamental plants and other goods, and tourism; natural climatic events can also be responsible for the movement of arthropods. We likewise have to consider that sometimes the introduction of the invasive species is voluntary, and even if the insect itself is helpful, can become a serious threat to a country’s biodiversity. The deliberate introduction into the new environment can be for productive purposes or as a control agent (the classical biological control, based on importation of natural enemies from the country of origin of the exotic pest). Rodolia cardinalis (Mulsant), imported in California in the late 19th century to control cottony cushion scale, has ever since been a textbook example illustrating the accomplishments of biological control.

Japonica cultivars' susceptibility to the rice water weevil Lissorhoptrus oryzophilus (Coleoptera: Curculionoidea: Brachyceridae)

Italy is the largest rice‐producing country in the European Union. In Italy, only japonica cultivars are listed in the Italian National Register. Almost all of the rice production is concentrated in the Po Valley, where the rice water weevil Lissorhoptrus oryzophilus Kuschel was first detected and settled. This study investigated the performance of this pest in terms of feeding, reproduction and plant injury on 10 rice cultivars chosen among the most widely grown in Italy. No‐choice experiments were conducted to evaluate the plant susceptibility to larval attack and to find out how cultivars can influence the adult leaf area consumption. The results gave evidence of different types of attack depending on the density of the insect (0.6 adults/plant vs. 0.9 adults/plant), the cultivar type and climatic conditions. Different cultivars with the same level of infestation gave different results in terms of productivity. Production was significantly affected by the larval presence in 4 of the 10 cultivars tested. A different population structure reflected a different damage severity. Statistically different values for total adult leaf area consumption were found according to adult female age and to the cultivar.

First record of Rhoptrocentrus piceus Marshall (Hymenoptera, Braconidae, Doryctinae) as parasitoid of Psacothea hilaris hilaris (Pascoe) (Coleoptera, Cerambycidae).

The species Rhoptrocentruspiceus Marshall (Hymenoptera: Braconidae) was reared from the larvae of the xylophagous beetle Psacotheahilarishilaris (Pascoe) (Coleoptera: Cerambycidae), an exotic pest of Ficus and Morus species native to eastern Asia. It was recorded in the north of Italy in September 2005. This discovery is the first report of this species as parasitoids of the yellow spotted longicorn beetle all over the world.

Salvia verticillata: Linking glandular trichomes, volatiles and pollinators

Plants have developed a plethora of signals to interact with other organisms, finally building up a sophisticate language for communication. In this context, we investigated Salvia verticillata L. (Lamiaceae), with the primary goal to link secondary metabolites and actual biotic relationships. We specifically analysed the volatile organic compounds (VOC) spontaneously emitted by leaves and flowers and determined the composition of the essential oils obtained from the aerial parts across 2015 and 2016. We merged information of chemical analyses to a micromorphological investigation on the glandular indumentum and to focal observations on the pollinator assemblage. The VOC profiles were highly variable, with the floral bouquet being the most complex. Flowers and leaves showed 37 and 20 exclusive compounds, dominated by 1,8-cineole (10.4%) and germacrene D (38.4%), respectively. Sesquiterpene hydrocarbons prevailed (83.3% leaves; 73.7% flowers) and 19 common compounds were detected. The oil profiles proved to be consistent across the two years: sesquiterpene hydrocarbons invariably dominated, with germacrene D, bicyclogermacrene and β-caryophyllene as main compounds. The whole plant epidermis is thickly covered by two types of glandular hairs: peltates and small capitates, both responsible for the synthesis of terpenes, finally resulting in the VOC emission and in the essential oil production. S. verticillata attracted mainly bees belonging to two functional groups: medium-sized and large bees, notwithstanding the small size of its flowers. At the site, Apis mellifera and different Bombus species were recorded, mainly interested in feeding on nectar. The literature survey on the isolated volatile compounds confirmed the hypotheses on the seduction strategies towards Apoidea.

Assessment of Vegetable and Fruit Substrates as Potential Rearing Media for Hermetia illucens (Diptera: Stratiomyidae) Larvae

Abstract Hermetia illucens (L.) (Diptera: Stratiomyidae) is able to consume a wide range of organic matter and is of particular interest for waste management. The nutritional value of preimaginal stages, in particular the protein content, makes this species a valid candidate for use as feed for other organisms. Vegetables and fruits are promising rearing substrates for insects produced for this purpose according to the EU regulation. In order to examine the effects of diets on insect performance and chemical composition, larvae were reared on the following substrates: 1) fruit (apple, pear, and orange); 2) vegetable (lettuce, green beans, and cabbage); and 3) mixed fruits and vegetables. High percentages of survival were observed on all diets, but there were differences among weights of larvae, pupae, and adults, with weights of larvae reared on mixed fruits and vegetables lower than on other diets. Pupae reared on the mixed diet were heaviest, and also morphometric measurements of adults were highest. Larvae reared on fruit diets had the highest fat content, comprising mostly saturated fatty acids; the highest content of essential n-3 fatty acids was found in vegetable reared larvae and that of n-6 in mixed reared larvae. Larvae reared on the mixed diet had the highest protein content. Calcium contents were high and moderate amounts of iron and zinc were found. H. illucens showed the capability to develop on vegetable and fruits diets displaying different nutrient profiles and biological performances.The best-performing rearing strategy should vary in relation to the final use of H. illucens.