CREA Journals (Consiglio per la ricerca in agricoltura e l’analisi dell’economia agraria)
Not a member yet
791 research outputs found
Sort by
EVOLUTION OF SENSORY ANTENNAL STRUCTURES IN THE ENSIGN SCALE INSECTS (HEMIPTERA COCCOMORPHA ORTHEZIIDAE)
Get PDFThe Ortheziidae (Hemiptera: Sternorrhyncha: Coccomorpha) are considered one of the most ancient families of Coccoidea. In this study, the antennal structures of species belonging to the Ortheziidae are examined and combined with data from a previous phylogenetic study as well as habitat preference data. Illustrations of the antennal structures (with a focus on the distribution of setae and specialized sensilla) for the type species of all genera in the Ortheziidae are provided. The three main ortheziid lineages can be recognized by their sensilla: (i) the Ortheziinae all possess coeloconic sensilla; (ii) the Newsteadiinae, which only includes Newsteadia, is characterized by a different type of coeloconic sensilla, here named Newsteadia-type coeloconic sensilla, and (iii) a clade that includes the Mixortheziinii, Nipponortheziini and Ortheziolini, all possess only basiconic sensilla
APHIDS UNDER STRESS. SPECIES GROUPS AND ECOLOGICAL FUNCTIONAL GROUPS OF APHIDS DEFINE HEAVY METAL GRASSLANDS OF CENTRAL EUROPE
Get PDFInterest in trace metals and the environmental effects of their deposition significantly increased recently. Ecological communities formed on soils with a high concentration of heavy metals are characterised by a particular composition of plants and invertebrates in response to unfavourable physical and chemical conditions and under a strong selective pressure. Calaminarian grasslands as well as other dry grasslands are fragile habitats, very rare in Central Europe; such areas are often protected within nature reserves. This paper is the first comprehensive study of aphids (Insecta: Hemiptera: Aphidomorpha) of the metalliferous areas in Central Europe. It helped to describe the species diversity of aphid communities related to the plants of heavy metal grasslands, define the level of relationships between aphids and plants of heavy metal habitats and determine diagnostic aphid species for assemblages forming in such post-industrial landscapes. On the basis of ecological groups determined for aphids, also the number and percent of the species which form them and their ratios structure aphid communities and their condition was defined. An elevated heavy metal content in the soil does not limit the species richness of such an aphid community in comparison with those of other dry grasslands. However, these aphid communities possess specific features resulting from the mixture of species arriving from dry calcareous and sandy grasslands. The concept of ecological functional groups for analysis of aphid communities is introduced. Such an approach is useful for describing aphid communities in time and the directions of their changes, thus helping to monitor successive changes and the habitat stat
FIRST INTERCEPTION OF TRICHOFERUS CAMPESTRIS (FALDERMANN, 1835) (COLEOPTERA CERAMBYCIDAE CERAMBYCINAE) IN ITALY
Get PDFThe Velvet Longhorned Beetle Trichoferus campestris (Faldermann, 1835) was intercepted for the first time in Italy, in the Naples harbour, during monitoring activities at entry points carried out in the context of the national project ASPROPI. T. campestris is widely polyphagous and able to colonize several woody species in both agricultural and forest environments. Moreover timber and solid wood items can be equally attractive to this pest. This additional report, in an area where other alien insect species had been identified in the past, emphasises how the national monitoring network represents a key element of the alert system designed to quickly counter the accidental introduction and spreading of exotic insect pests
HEMIPTERA AND COLEOPTERA ON CHENOPODIUM QUINOA
No full textHeteroptera and Coleoptera, collected in experimental fields of Chenopodium quinoa, are reported. Twelve species of Heteroptera and five species of Coleoptera were recorded; a large number of the phytophagous species, Lygus rugulipennis, Orthotylus flavosparsus, Aphis craccivora, A. fabae and Chaetocnema tibialis, and of the predator Hippodamia variegata were found
BACTERIA ASSOCIATED TO RHYNCHOPHORUS FERRUGINEUS (OLIVIER) (COLEOPTERA DRYOPHTHORIDAE) IN ITALY
Get PDFThirty-five bacterial strains were selected on the basis of colony morphology from larvae and pupae of Rhynchophorous (Olivier) ferrugineus collected from infested Phoenix canariensis Chabaud trees growing in different Italian locations. 16S rDNA sequencing showed that bacteria isolated from larvae were mostly Gram positive and belonged to Bacillus, Brevibacillus and Paenibacillus genera. Bacteria isolated from pupae were affiliated to Bacillus and five different Gram negative genera (Alcaligenes, Morganella, Myroides, Providencia and Serratia). Some strains produced lytic enzymes like chitinase, lecithinase, lipase and protease in vitro. The enthomopathogenic strains belonging to Bacillus thuringiensis, Providencia rettgeri and Serratia marcescens species may be considered of interest as potential biocontrol agents of R. ferrugineus
DISTRIBUTION, PREFERENCE AND PERFORMANCE OF PHORACANTHA RECURVA AND PHORACANTHA SEMIPUNCTATA (COLEOPTERA CERAMBYCIDAE) ON VARIOUS EUCALYPTUS SPECIES IN TUNISIA (1)
Get PDFThe two eucalyptus borers Phoracantha semipunctata and P. recurva were accidently introduced in Tunisia in1962 and 1999, respectively. Their relative distribution is still unknown and very little is known about their preferencesand performances in various host species under different Tunisian climates. We combined field data and laboratoryfollow-up, in order to define their present distribution, their relative abundance and to test the effects of sites andEucalyptus species on attack density, reproductive and developmental performances and productivity of insects. Thestudy was carried out in Eucalyptus plantations of ten localities ranging from humid to arid. Choice preference andcolonization of various selected Eucalyptus species by the two borers were studied with standing trap trees and traplogs. Tree species differed among localities, but all localities contained at least one of the two species E.gomphocephala and E. camaldulensis, both being well appreciated by the two Phoracantha species. It appeared thatboth beetle species were present in all localities but P. recurva was dominant over P. semipunctata everywhere. Insectcharacteristics depended on attack localization on tree stem; attack densities were higher on the lowest than on theupper parts. It is perfectly coherent that the density of emerging beetles correlated positively with attack density,number of young larval galleries, larval survival and adult success in the trap tree experiment. High larval survival andadult success resulted in high offspring productivity
AN UPDATED LIST OF THE SCALE INSECT (HEMIPTERA COCCOMORPHA) FAUNA OF SOME SICILIAN ENDEMIC PLANTS
Get PDFIn this study Authors report scale insects (Hemiptera: Coccomorpha) species for the first time recorded on some endemic plants of Sicilian flora, namely, Abies nebrodensis Mattei (Pinaceae), Astragalus siculus Biv. (Leguminosae), Betula aetnensis Rafinesque (Betulaceae) and Zelkova sicula Di Pasquale Garfi & Quezel (Ulmaceae).Abies nebrodensis is present in a single small population on Madonie Mountains. On this conifer the fir scale Parlatoria parlatoriae (Šulc) (Diaspididae) was collected. On B. aetnensis, that colonizes the lava substrates of Etna Volcano mainly at 1300–1900 m.a.s.l., a consistent population of an undescribed Diaspidiotus species (currently being described) was collected. Moreover Lepidosaphes ulmi (Linnaeus) (Diaspididae) was detected and collected on A. siculus which is characteristic plant of the upper part of the volcano. Zelkova sicula is a very rare relict of the Tertiary, belonging to a genus of plants already extinct in Continental Europe; with only two small populations living in restricted woodland areas in south oriental Sicily where two scale insects were collected: Aspidiotus nerii (Costa) (Diaspididae) and Parthenolecanium sp. (Coccidae)
WING DIMORPHISM IN TUSCAN POPULATIONS OF RHYZOBIUS LITURA (FABRICIUS) (COLEOPTERA COCCINELLIDAE)
Get PDFWing polymorphism is well known among beetle families such as Carabidae, Staphylinidae, Tenebrionidae and Curculionidae, but it is relatively uncommon among Coccinellidae. Rhyzobius litura (Fabricius) is one of the Italian Coccinellidae species, with a dimorphism involving the second pair of wings which may be fully developed (macropterous) or may assume a ribbon-like structure (brachypterous). Specimens of R. litura collected from localities of the Tuscan Archipelago (islands of Elba, Gorgona and Pianosa, Province of Leghorn) and Tuscan hinterland (Lorenzana, San Giuliano and Ponsacco, Province of Pisa) were examined for wing dimorphism. Different sampling techniques were used: Malaise traps, pitfall traps, beating tray, collecting net and visual search. Specimens collected were either adults or larvae, these latter were reared till maturity and then examined. Results showed a remarkable homogeneity within the examined populations, which were always constantly or strongly brachypterous or macropterous. Most of the populations examined were composed of specimens which were brachypterous or with a high level of brachyptery, but the population from the island of Pianosa was entirely composed of macropterous specimens. The hypothesis that the emergence of a long-winged population could be due to geographical isolation is discussed
Explore inhabitants’ perceptions of wildfire and mitigation behaviours in the Cerrado biome, a fire-prone area of Brazil
Get PDFFire represents an important natural feature of Brazilian landscape, especially in the Cerrado biome. The Cerrado is the economic livelihood of thousands of people from rural areas in Brazil. It is one of the most important hotspot of biodiversity in the world but also it is a fire-prone area thanks to the high flammability index of the vegetation. Residents and native people of this environment use fire very frequently. The majority of wildfires are caused by humans, though there are some aggravating natural factors affecting the risk, intensity and severity of wildfires. Since residents are continuously involved in fire suppression activities, understanding their perceptions is important for the decision makers who must assess the local capacity to preserve natural resources. This study explores perceptions about wildfire risk and fire mitigation behaviors within three municipalities of the state of Tocantins (Brazil). The study demonstrates that survey participants perceived wildfire risk as rather high, although the perceptions were complex and conflicting among interviewees. A wide range of confused perceptions about fire ignition and heterogeneous point of view have carried out form the survey. However, the residence of interviewees and their educational attainment result the variables that significantly (p-value <0.05) affect the inhabitants’ perceptions
EFFECT OF TEMPERATURE ON LIFE HISTORY OF CHRYSOMPHALUS DICTYOSPERMI (MORGAN) (HEMIPTERA DIASPIDIDAE)
Get PDFThis study documented the life table parameters of Chrysomphalus dictyospermi (Morgan) (Hemiptera: Diaspididae) reared on pumpkins at three different constant temperatures (22.5, 25, 27.5, and 30°C±1), constant relative humidity (65±5%) and long photoperiod (16:8 L:D). The intrinsic rate of increase (rm) was 0.03 female/female/day at 22.5°C, 0.05 females/female/day at 25 °C, 0.04 females/female/day at 27.5°C, and 0.06 females/female/day at 30°C. The reproductive rate (Ro) was 22.89, 50.96, 24.79, and 70.58 females/female at 22.5, 25, 27.5, and 30°C, respectively. The generation time (To) was found 102.17, 67.04, 66.21, and 68.48 days at 22.5, 25, 27.5, and 30°C, respectively. In addition the gross reproduction rate (GRR) was calculated as 32.76, 66.96, 33.07, and 88.60 females/female, the doubling time (T2) was22.62, 11.82, 14.29, and 11.15 days, and the finite rate of increase (λ) was 1.03, 1.06, 1.04, and 1.06 females/female at22.5, 25, 27.5, and 30°C, respectively