Tesi di Dottorato

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Monitoraggio di un gruppo di insetti predatori, i coleotteri carabidi, ai fini della conservazione e dello sviluppo sostenibile dell'agricoltura nel parco nazionale della Sila
(Università della Calabria, 2020-02-13) Cavaliere, Francesco; Cerra, Maria Carmela; Brandmayr, Pietro; Giglio, Anita
Agricultural management practices are known to cause lethal and sub-lethal effects on animals inhabiting croplands. The persistence and residual accumulation of pesticides in the soil are detrimental to the environment and pose a risk for human health and for species providing biocontrol ecosystem services. Carabid beetles are useful bioindicators to evaluate the ecological effects of agrochemicals due to their ecological role as predators in farmland. In order to assess the sub-lethal effects at the community, species and organism levels, on non-target species caused by regular pesticide applications, an environmental monitoring was performed over a period of two years, in two sites around the agricultural area to Sila National Park. One site is a conventional farm (39°16'58.05"N, 16°38'43.26"E, 1240 m a.s.l., Torre Garga Farm, Calabria, Italy), it was treated with herbicides, pesticides and fungicides used for pest control. The second site, chosen as control, is an organic farm (39°17'10.28"N, 16°42'28.33"E, 1150 m a.s.l., Macchia di Tuono Farm, Calabria, Italy). To check the direct sublethal effect of field exposure on species abundance and density at the community level, carabid beetles were collected in vivo by pitfall traps and identified using dichotomous keys. To asses the direct sub-lethal effect of field exposure at the organism level, the body size, the constitutive immune responses and genotoxicity we quantified in adults of Harpalus rufipes, a generalist predator taxonomically and ecologically well known, widely distributed and easy to collect in crops. The findings of this study indicated that chemical treatments admitted in the conventionally managed fields have negative effects on the abundance and density of species inhabiting croplands, the low level of PO and lysozyme-like enzyme activities and the DNA damage recorded in haemocytes indicated that field treatments might influence this non-target soil-dwelling species. However, field treatments did not cause morphometric changes in the body size of adults. The reduction of humoral responses and the genotoxic effect recorded on haemocytes may result in an increased susceptibility of this species to pathogens. From an ecoimmunological point of view, a modification of other basic life history traits such as reproduction, dispersal activity and predation may occur with effects on the adult fitness, resulting in changes of the population structure and in a reduction of the biocontrol activity for pest species in agroecosystem.
Investigating how movement affects prey camouflage using an insect predator
(2019-06-09) Umeton, Diana; Canonaco, Marcello; Brandmayr, Pietro
Patterns that help prey camouflage themselves whilst stationary prove to be ineffective once prey move. Given that motion breaks camouflage, can a moving prey ever be effectively concealed? Recent studies have found that certain patterns might help prey deceive their predators whilst moving, as in the case of ‘motion dazzle’. However, research with moving prey has been conducted using only humans or birds as predator models, and consequently, it is now known how other predator species might behave. In addition, it is important to know not just how motion affects camouflage, but also how the speed of motion can affect the efficacy of different defensive patterns. This thesis aims to address these current gaps in the field. First, I explore the visual acuity in a group of insect predators, the praying mantids, to explore if different species vary in their visual acuity, which could impact on what they can perceive and which selective pressure they could exert on prey defensive patterns. Second, using praying mantids tracking computer-generated stimuli, I empirically investigate how cryptic and conspicuous patterns might enhance the survival of moving prey. In particular, I specifically investigate if high contrast striped prey could reduce predation risk through the visual phenomenon known as “flicker fusion effect”. I found that when prey were slow moving, all patterns were equally detectable by the mantids. However, once prey moved at faster speed, a cryptic pattern was more likely to be tracked than a more conspicuous black-and-white striped pattern suggesting that the latter was successful in inducing flicker fusion effect in praying mantids’ eyes. This thesis starts to disentangle how pattern and speed could combine to help camouflage an animal when moving through its environment. The outcome of the study are discussed in the wider context of how animals coloration and behaviour evolved together to confer them survival advantages.
Biodiversità dei carabidi e conservazione degli ambienti forestali
(2014-03-25) Pulieri, Valeria; Cerra, Maria Carmela; Brandmayr, Pietro
4 Abstract Resilience, stability and resistence of forest ecosystems are the main properties providing the conservation of those habitats and allowing the maintenance of processes essential for the “ecosystem services” supply. In front of climate change and other disturbances coming from human activities, it is of fundamental importance to watch and check stability status of ecosystems. Ground beetles, good bioindicators, by their community composition, functional groups and morphometric sensitivity, provide indicators on habitat conservation evaluation and contribute to identify little changes among areas looking similar. The analisys of biodiversity could be improved by considering the above factors, enhancing the functional role of single species of the community.
Impatto sull'antropodofauna di prodotti ammessi contro la bactrocera oleae (Rossi, 1790) in olivicoltura biologia)
(2013-05-07) Belfiore, Tiziana; Brandmayr, Pietro; Canonaco, Marcello

Tesi di Dottorato

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