Academic literature on the topic 'Castanea sativa L'

Durante as escavações arqueológicas realizadas no Castro de Monte Mozinho, nos anos de 2008 e 2009, foram efetuadas recolhas de sedimentos com vista à realização de estudos de arqueobotânica. A presente discussão centra-se na componente antracológica das recolhas realizadas no Compartimento 1 do setorA-2008 do povoado. Os resultados obtidos permitiram a identificação de um espectro paleoflorístico no qual se destaca a presença de castanheiro (Castanea sativa Mill.), carvalho caducifólio (Quercus tipo caducifólia), dois tipos de leguminosas, choupo (Populus L.) e pinheiro bravo (Pinus pinaster Ait.). Em segundo plano surgiram urze (Erica L.), amieiro-negro (Frangula alnus Mill.), freixo (Fraxinus L.), Prunus L. (género ao qual pertencem diversas espécies domésticas e silvestres tais como a ameixeira, o pessegueiro, o abrunheirobravo), salgueiro (Salix L.), ulmeiro (Ulmus L.) e azinheira ou sobreiro (Quercus tipo perenifólia).O número de espécies e a diversidade ecológica do conjunto analisado permitiu concluir que a recoleção de madeiras ocorreu em três formações vegetais distintas: bosques climácicos dominados por carvalhos; matos subseriais arbustivos resultantes da degradação da primeira formação; e formações ripícolas. Odestaque de Castanea sativa L. nas amostras permitiu algumas reflexões acerca da sua integração nas dinâmicas ecológicas e económicas de época romana. Charcoal analysis in Monte Mozinho: a paleoecological approach to the remains from compartment 1, sector A-2008 - During the archaeological excavations in the roman settlement of Castro de Monte Mozinho, taken place in 2008 and 2009, several soil samples were collected in order to obtain relevant archaeobotanical data. The present article focuses on the compartment 1, sector A-2008. The results obtained allowed the identification of a paleofloristic spectre, in which stands out the presence of sweet chestnut (Castanea sativa Mill.), deciduous oak (Quercus deciduous), Leguminosae, poplar (Populus L.) and cluster pine (Pinus pinaster Ait.). In small numbers, several other species were identified, e.g. heath (Erica L.), alder buckthorn (Frangula alnus Mill.), ash (Fraxinus L.), Prunus L. (genus with a wide range of species – plum tree, cherry plum, peach, etc.), willow (Salix L.), smooth-leaved elm (Ulmus L.) and cork oak or holm oak (Quercus evergreen). The variety of species analysed throughout the study allowed us to assume that firewood collection took place in three distinct plant formations: climacic forests of deciduous oak, subserial formations originated by its degradation and riparian vegetation. On the other hand, the relevance of Castanea sativa in these samples allowed the discussion of its integration in the regional Roman ecological and economical dynamics.

Sprouted buds of eight mature plus-trees of Castanea sativa were collected from two natural populations (Mt. Paiko and Mt. Hortiatis, Greece). Explants were cultured on Murashige and Skoog (MS) medium (three concentrations of macro and micro-elements) combined with three concentrations of BAP (6-Benzylaminopurine). Results were evaluated based on three multiplication traits: (a) number of shoots produced, (b) length of the longest shoot segments and (c) percentage of responsive explants. A high genotype-dependant variation for the number of shoots produced per explant was detected. MS medium at full salt strength and 0.2 mg l-1 BAP provided the best results based on the multiplication traits measured. Elite mature tree P-2 proved to be highly favourable for multiplication. Rooting was attempted on ½ MS medium at five different NAA concentrations. Successful rooting (56%) was obtained by using 0.50 mg l-1 NAA in vermiculite medium after eight weeks. These results indicate that the P-2 genotype can be micropropagated from the protocol developed for ornamental purposes, clonal testing and tree improvement applications.Â

Castanea sativa cv. ‘Garrone Rosso’ and ‘Marrone di Castel del Rio’ are two of the most prized varieties in Italy due to their valuable and healthy nuts used for fresh consumption and in the confectionery industry. Despite the growing demand for chestnuts, there are constraints regarding plant propagation that hamper the renewal and new planting of orchards in different areas. Castanea sativa is susceptible to diseases that have caused a reduction in its area of production. For this reason, in vitro culture represents a valuable technique for germplasm preservation and plant multiplication enabling production of a high number of plants for use in breeding programs. Here we present an in vitro micropropagation protocol for Italian Castanea sativa cv. ‘Marrone di Castel del Rio’ and cv. ‘Garrone Rosso’ to contribute to the preservation and enhancement of the Italian germplasm. Nodal explants were used as the starting material for in vitro establishment. The cv. ‘Marrone di Castel del Rio’ showed a high percentage of survival explants (92%) when subjected to long bleach exposure (25 min), in contrast to what was observed for the ‘Garrone Rosso’ cultivar. Ascorbic acid was found to be the best compound to counteract phenol exudation. The MS3B and DKW media supplied with 0.5 mg/L BAP were effective for in vitro establishment, while the DKW medium (0.1 mg/L BAP and 0.05 mg/L IBA) was preferable for the proliferation phase. A double-layer rooting methodology was used and 35% rooting was observed with 25 mg/L IBA rooting treatment.

Pollen viability and germinability in some European chestnut genotypes was assessed in this study. In 10 chestnut genotypes, percentages of pollen viability were generally high and often around or over 80%. The pollen germination percentages of the genotypes were significantly affected by media sucrose concentrations. At optimum sucrose concentrations pollen germination percentages varied between 21.97 and 43.68% in 2004, 3.95 and 31.97% in 2005 and 6.79 and 31.03% in 2006, across all genotypes. The highest pollen germination percentage was obtained from 10% sucrose concentration in all years. Although, in 2006, a highly marked positive correlation (r = 0.80) was determined for the viability and germination percentages, no significant relation between the viability and germination percentages r = –0.54 and r = –0.05, respectively) was found in 2004 and 2005. In 2005 and 2006, germination percentages declined compared to 2004.

633.88:582.688.3(560) Arbutus unedo L. and Arbutus andrachne L., belonging to Ericaceae family and being evergreen, are two important species having economic values in natural flora of Turkey. These species spread as enclave in the Black Sea Region, while they are found naturally in the Mediterranean and Aegean Region of Turkey. Arbutus unedo, whose fruits contain a high amount of sugar (42% - 52%), is widely preferred in the subbranchs of the food industry such as jam, marmalade and sweetener, especially in the beverage industry in Europe. Arbutus andrachne is a species that has an effect on the circulatory system and besides it has antihemorrhagic and urinal antiseptic properties. In this study, floristic characteristics of Arbutus unedo and A. andrachne, spreading in places where the Mediterranean climate is predominant in Turkey, being characteristic elements of maquis formation in coastal areas of Black Sea Region, are investigated. Within the scope of the study, sample plots were taken in Bartın, Kastamonu, Sinop, Samsun, Ordu and Trabzon regions. It was determined that the most common native species accompanying these species (only woody plant taxa) are different. These species are frequently spread together with Castanea sativa in Bartın, Quercus sp. + Carpinus betulus in Kastamonu, Castanea sativa + Pinus sylvestris + Fagus orientalis in Sinop, Pinus brutia in Samsun, Quercus sp. in Ordu and Quercus sp. + Carpinus betulus in Trabzon. In addition, shrub species such as Erica arborea, Laurus nobilis, Ruscus aculeatus, Smilax excelsa, Rubus sp. and Cistus sp. accompany to these species in all of these sample plots.

ABSTRACT The objective of this study was to evaluate the effect of the growth regulator indole butyric acid (IBA) on the rooting of mini-cuttings of Castanea crenata x C. sativa hybrid clones. Minicuttings were left to root for 60 days in an acclimatized greenhouse and then transferred to a shade house for a further 30 days. The experiment was a random block design with a double factorial arrangement consisting of five IBA concentrations (0, 2,500, 5,000, 7,500 and 10,000 mg L-1) and five clones, with three repetitions, composed of eight minicuttings per repetition. The use of IBA significantly affected the rooting and survival of the mini-cuttings, and good rates were achieved. However, at each IBA concentration we found significant differences between clones, thus suggesting that the conditions of the process of mini-cutting propagation should be specifically adapted to each particular clone.

The antioxidant properties of almond green husks (Cvs. Duro Italiano, Ferraduel, Ferranhês, Ferrastar and Orelha de Mula), chestnut skins and chestnut leaves (Cvs. Aveleira, Boa Ventura, Judia and Longal) were evaluated through several chemical and biochemical assays in order to provide a novel strategy to stimulate the application of waste products as new suppliers of useful bioactive compounds, namely antioxidants. All the assayed by-products revealed good antioxidant properties, with very low EC50 values (lower than 380 μg/mL), particularly for lipid peroxidation inhibition (lower than 140 μg/mL). The total phenols and flavonoids contents were also determined. The correlation between these bioactive compounds and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, reducing power, inhibition of β-carotene bleaching and inhibition of lipid peroxidation in pig brain tissue through formation of thiobarbituric acid reactive substances, was also obtained. Although, all the assayed by-products proved to have a high potential of application in new antioxidants formulations, chestnut skins and leaves demonstrated better results.

Microsatellite or simple sequence repeat (SSR) markers show many characteristics of the ideal molecular marker, and recent studies have shown that loci developed in one species may allow analysis in taxonomically related species. In this study, 52 primer pairs developed in two oak species—Quercus robur L. and Quercus petraea (Matt.) Lieb.—were used to amplify DNA of 5 chestnut cultivars; 28 of them yielded amplicons and 12 polymorphic loci were selected and used to fingerprint 12 european chestnut (Castanea sativa Mill.) cultivars grown in the Piedmont region of northwestern Italy. The number of alleles per locus ranged from 3 to 8, mean expected heterozygosity was 0.592 (range: 0.288 to 0.868), and mean observed heterozygosity was 0.667 (range: 0.333 to 1.000). The results demonstrate the usefulness of some SSR markers isolated in Quercus for the fingerprinting and genetic mapping of Castanea cultivars.

La terapia di eradicazione contro Helicobacter pylori (H. pylori) comporta la riduzione dei livelli di IL-8 nella mucosa gastrica e il controllo del rischio di cancro e ulcera. L’approccio terapeutico corrente è minacciato dall’antibiotico resistenza. Pertanto, la scoperta di composti vegetali di origine dietetica con effetto anti-infiammatorio e anti-batterico potrebbe contribuire al controllo della gastrite e migliorare il profilo di sicurezza della terapia. Le piante contenenti tannini, inclusi gli ellagitannini, hanno già dimostrato effetti gastro-protettivi in studi preclinici, ma richiedono ulteriore validazione farmacologica. Castanea sativa Mill. (castagno) rappresenta una fonte di tannini utilizzata tradizionalmente contro disturbi gastro-intestinali e respiratori. Gli estratti di C. sativa Mill. sono ammessi come ingredienti nutraceutici in diversi paesi europei sulla base del loro impiego tradizionale; d’altra parte, la loro composizione fitochimica e la loro attività biologica sono scarsamente studiate. Ciò comporta un limite per la documentazione di indicazioni salutistiche (health claims). L’obiettivo del seguente progetto di dottorato è stato di caratterizzare estratti idroalcolici ottenuti da frutti e foglie di C. sativa Mill., con un’attenzione particolare alla valutazione della composizione in tannini. In parallelo, gli estratti sono stati studiati come potenziali candidati contro la gastrite ed H. pylori, attraverso un approccio multidisciplinare che ha compreso esperimenti in vitro di tipo farmacologico e microbiologico. Nell’ottica di una possibile applicazione nutraceutica, il lavoro ha considerato l’importanza dell’origine botanica degli estratti e ha valutato l’impatto della digestione gastrica sulla stabilità dei composti bioattivi. I risultati conseguiti sugli estratti del frutto (la castagna) sono stati pubblicati dal gruppo di ricerca (Sangiovanni and Piazza et al. 2018): in breve, seguendo un approccio bio-guidato, gli estratti idroalcolici di frutti da 5 varietà di castagno sono stati utilizzati nel modello di rilascio di IL-8 indotta da TNFα in cellule epiteliali gastriche (AGS). Due delle varietà (Venegon e Verdesa) sono emerse per la loro attività inibitoria promettente (IC50 minore di 10 μg/mL) e di conseguenza sono state caratterizzate per il loro contenuto polifenolico. L’analisi HPLC-MS ha rilevato la presenza di tannini condensati (proantocianidine oligomeriche) negli estratti ottenuti dalle componenti esterne della castagna (pericarpo ed episperma), i quali hanno correlato con l’inibizione di IL-8 (IC50s minori di 0.5 μg/mL); al contrario, la parte edibile del frutto (l’endosperma) è risultato privo di proantocianidine e attività biologica. I tannini idrolizzabili tipici della corteccia di castagno, ovvero gallotannini ed ellagitannini, sono risultati assenti nel frutto. In accordo con la letteratura riguardante i tannini, gli estratti hanno mantenuto la loro attività inibitoria in seguito alla simulazione in vitro della digestione gastrica. Inoltre, l’attività biologica è stata modestamente intaccata da brevi trattamenti termici (fino a 100°C per 30 min), suggerendo la possibilità di recuperare le parti esterne per l’arricchimento di una farina di castagne bioattiva. Di conseguenza, una farina arricchita di episperma è stata preparata rispettando la composizione originale della castagna, quindi è stata estratta e valutata per l’inibizione di IL-8 (IC50 = 16.35 μg/mL), rivelando una potenziale applicazione nutraceutica. Seguendo un approccio simile sono stati studiati gli estratti idroalcolici delle foglie appartenenti alle varietà più promettenti (Venegon e Verdesa). Diversamente dal frutto, nella foglia sono stati riconosciuti gli ellagitannini castalagina e vescalagina (1-2%), i quali hanno stimolato l’approfondimento di un potenziale effetto contro H. pylori. In particolare, sono stati valutati l’effetto anti-batterico e anti-infiammatorio in un modello di co-coltura di cellule epiteliali gastriche infettate con il batterio (cellule tumorali AGS a confronto con cellule non-tumorali GES-1). Le foglie hanno inibito il rilascio di IL-8 con IC50 inferiori a 30 μg/mL in entrambi i modelli cellulari e hanno inibito la crescita batterica a 100 μg/mL. La simulazione della digestione gastrica ha moderatamente inficiato gli effetti biologici (2 volte) e il contenuto in fenoli totali, suggerendo la loro probabile stabilità a livello gastrico in seguito ad assunzione orale. Per gli ellagitannini castalagina e vescalagina è stato dimostrato lo stesso effetto inibitorio (IC50 di IL-8 minore di 16 μM; MIC = 25 μM), ma a concentrazioni che non spiegano completamente l’effetto dell’estratto originale; di conseguenza, la sinergia con altri polifenoli potrebbe giocare un ruolo. Il lavoro sperimentale ha posto le prime basi per il recupero a scopo nutraceutico di scarti agricoli della coltura del castagno, quali le parti esterne del frutto e le foglie, sottolineando il ruolo dei tannini per la loro attività biologica.
The eradication therapy against Helicobacter pylori (H. pylori) accounts for the reduction of IL-8 levels in gastric mucosa and the related risk of gastric cancer and ulcer onset. However, the current therapeutic approach has being challenged by antibiotic resistance. The discovery of natural compounds from edible plants with anti-inflammatory and anti-bacterial activities may contribute to the control of the disease and improve the safety profile of eradication. Plants producing tannins, including ellagitannins, have already shown pre-clinical gastroprotective evidences, but pharmacological validations are still required. Accordingly, Castanea sativa Mill. (sweet chestnut) is a well-known source of tannins, traditionally used for gastro-intestinal and respiratory diseases. On the base of the traditional indication, extracts from sweet chestnut are currently allowed as botanical ingredients by several European countries; however, their phytochemical composition and biological activity are poorly investigated, thus limiting the substantiation of health claims. The aim of the phD project was to characterize hydroalcoholic extracts from fruit and leaves of sweet chestnut, with a particular attention to tannin composition. In parallel, extracts were evaluated as potential candidates against gastritis and H. pylori through a multidisciplinary approach, including in vitro pharmacological and microbiological experiments. In the view of nutraceutical application, the work took into account the importance of the botanical origin of the extracts and evaluated the impact of gastric digestion on the stability of natural compounds. The results obtained on the fruit (chestnut) have been published by the research group (Sangiovanni and Piazza et al. 2018): in brief, following a bio-guided approach, hydroalcoholic extracts from chestnut of five different varieties were screened for their ability to impair TNFα-induced IL-8 release in human gastric epithelial cells (AGS). Two varieties (Venegon and Verdesa) emerged for their promising inhibitory activity (IC50s less than 10 μg/mL) and further characterized for their polyphenolic content. HPLC-MS analysis revealed the presence of condensed tannins (oligomeric proanthocyanidins) in extracts from the outer part of chestnut (pericarp and episperm), which correlated with IL-8 impairment (IC50s less than 0.5 μg/mL); on the contrary, the edible part (endosperm) was devoid of proanthocyanidins and inactive. Of note, hydrolysable tannins typical of the bark of sweet chestnut, namely gallotannins and ellagitannins, were absent in chestnut. In line with the literature on tannins, extracts maintained their inhibitory activity after the simulation of gastric digestion. Moreover, the bioactivity was modestly affected by the application of brief thermal treatments (till 100 °C for 30 min), thus suggesting the possibility of recovering chestnut shell for the enrichment of a bioactive chestnut flour. Consequently, an episperm-fortified flour was prepared respecting the original composition of chestnut, then extracted and assayed again for IL-8 impairment (IC50 = 16.35 μg/mL), thus demonstrating the potential application of chestnut by- products in nutraceuticals. Following a similar approach, hydroalcoholic extracts from leaf belonging to the most promising varieties (Venegon and Verdesa) were investigated. Contrarily to the fruit, the ellagitannins castalagin and vescalagin were revealed (1-2%) in leaf, thus prompting further studies on the anti-H. pylori effect. In particular, the antibacterial and anti-inflammatory activity was evaluated in a co-culture model of gastric epithelial cells infected with the bacteria (tumoral AGS in comparison with non-tumoral GES- 1). Leaf extracts inhibited IL-8 release in both the infected cells with IC50s lower than 30 μg/mL and impaired the bacterial growth at 100 μg/mL. After simulated gastric digestion, these bioactivities were moderately impaired (2 folds); in paralleled, a slight decrease in total phenols content was observed, thus suggesting their possible stability at gastric level after oral consumption. Ellagitannins castalagin and vescalagin exhibited the same inhibitory effects (IC50 on IL-8 less than 16 μM; MIC = 25 μM), but at concentrations unable to completely explain the effect of the whole extract; therefore, the synergy with other polyphenols could play a role. The experimental work sustained for the first time the potential anti-gastritis application of by- products from sweet chestnut, such as chestnut shell and leaf, pointing out the role of tannins for the biological activity.

A antecipação de quase uma semana do início da estação anual de crescimento da vegetação lenhosa da zona temperada do Hemisfério Norte, entre 40 e 70 ° N de latitude foi detectada desde 1980, e tem sido considerada um dos primeiros sinais do aquecimento global (0,6 t 0,2 OC) do planeta, durante o século XX. Tal acréscimo tem sido atribuído, em grande parte, ao aumento da concentração de gases com efeito de estufa (GHGs) na atmosfera, tais como o vapor de água (vH20), o dióxido de carbono (CO2), o metano (CH4), etc., resultante das actividades humanas. A concentração de CO2 na atmosfera aumentou mais de 31 %, desde o início da Era Industrial em meados do século XVIII (280 ppmv) até final do século XX (370 ppmv). De acordo com as projecções mais recentes feitas pelo IPCC continuará a aumentar, podendo chegar a valores entre 400 e 540 ppmv por volta de 2050, e de 540 a 970 ppmv até ao final do século XXI, se não forem cumpridas as medidas de mitigação das emissões de GHGs estabelecidas no Protocolo de Quioto. O impacto das mudanças no ambiente sobre a produtividade de cobertos arbóreos foi analisado com base em estudos feitos sobre a acção combinada entre a duplicação da concentração actual de CO2 na atmosfera coma temperatura do ar, irradiàricia solar, disponibilidade de água e de azoto no solo, no metabolismo do carbono e relações hídricas da vegetação lenhosa de regiões com climas temperado, incluindo o tipo mediterrânico. Tais estudos foram realizados no campo com árvores aclimatadas a atmosferas enriquecidas em CO2 utilizando sistemas FACE, câmaras de topo aberto (OTCs), locais próximo de fontes geológicas de CO2, e com plantas jovens em câmaras e estufas com ambiente controlado. Os estudos apresentados demonstram que o crescimento de plantas C3 em atmosferas enriquecidas em CO2, em geral, o dobro do teor actual, durante curtos períodos de tempo, em média, uma estação de crescimento, aumenta a taxa de assimilação de carbono, em cerca de 40 a 60 %, comparativamente às plantas desenvolvidas àconcentração ambiente de CO2. Porém, o estímulo na fotossíntese é reduzido para 20 a 30 %, durante o crescimento em elevada concentração de CO2 de médio e longo prazo, pelo menos em plantas lenhosas florestais, devido à regulação negativa da capacidade fotossintética. Durante a exposição de curto prazo a elevado teor de CO2 ambiente, associada a secura severa temporária do solo, o estímulo na taxa de fotossíntese também é reduzido, em espécies lenhosas florestais, quer em condições naturais (por exemplo, na Pinus taeda L.), quer em ambiente controlado (e.g. Castanea sativa Mill.). A exposição de curto prazo, cerca de 4 meses, à duplicação do teor actual de CO2 na atmosfera, pode aumentar até cerca de 40%, a produção de biomassa total de espécies lenhosas florestais da zona temperada, incluindo espécies mediterrânicas. Porém, tal estímulo é reduzido durante o crescimento prolongado destas plantas em atmosferas enriquecidas em CO2. Os estudos apresentados também demonstram que a resposta de plantas lenhosas florestais a elevada concentração de CO2 na atmosfera, associada a deficiência de azoto no solo também decresce. Por exemplo, a aclimatação de médio prazo a elevado teor de CO2e défice de azoto, em ambiente controlado, não aumentou a taxa fotossintética de sobreiros jovens (Quercus suber L.), o que sugere que o impacto previsível da duplicação do teor actual de CO2 na atmosfera, será mínimo na produtividade desta espécie, em solos com deficiência de azoto, como ocorre em condições naturais. Todavia, a duplicação do teor actual de CO2 na atmosfera protege o aparelho fotossintético dos efeitos lesivos do aumento temporário da temperatura do ar e da irradiância solar, associados ou não à secura severa do solo, estimulando a actividade de mecanismos fotoprotectores, ao nível das folhas. O aumento da concentração de CO2 na atmosfera também reduz a abertura estomãtica (20 a 40%) e a transpiração, o que tem efeitos positivos na eficiência de uso da água das plantas. Todavia, os estoumas respondem menos ao aumento do teor de CO2 na atmosfera, quando o défice de pressão de vapor de água entre as folhas e o ar é elevado, associado a stresse hídrico severo no solo. ### Abstract - The mean annual growing season of temperate-zone trees at northern latitudes between 40 and 70° N begins earlier by ca. seven days. lt was detected in the early 1980s and has been considered one of the first signs of the effects of global warming (0.6 ± 0.2 °C) of the Earth, during the 20th century. Part of this warming has been now attributed to the increase of the man-made greenhouse gas (GHGs) emissions to the atmosphere, like water vapour (vH2O), carbon dioxide (CO2), methane (CH4), etc. Since the middle of le century, when Industrial Era started to the end to the 20th century, the atmospheric CO2 concentration increased by more than 31%, from 280 to 370 ppmv, and it W11 increase, substantially in the future, if the policies under Kyoto Protocol are not implemented. According to the projections made by the IPCC, the atmospheric CO2 concentration can arise to values between 400 and 540 ppmv by 2050, and from 540 to 970 ppmv by the end of 21tth century. The impact of environmental changes on tree productivity was examined through the studies made about the combined action of the elevated CO2 concentration in the atmosphere (ca. 700 ppmv) and other climate or/and ambient factors (temperature, solar irradiance, water deficits, nutrient: limitation, particularly nitrogen) on carbon metabolism and water relations. These studies were made on the field with Temperate-zone and Mediterranean trees using several systems of CO2 enrichment, namely FACE rings, Open Top Chambers (OTCs), CO2 springs and controlled environment (growth chambers). The studies presented in this work show that growing C3 plants in enriched CO2 environment, in general, the doubling of the present content, during short-term, on average, one annual growing season, increases the carbon assimilation rate by ca. 40 to 60 %, comparatively to plants growing at ambient [CO2]. However, at least in woody plants, this stimulation is reduced to 20 to 30 %, during either middle or long-term exposure to elevated [CO2], due to down-regulation of photosynthetic capacity. That stimulation is also reduced during short-term exposure to elevated [CO2] of woody plants, when combined with temporary severe soil drought, either in the field (e.g. Pinus taeda L.) or in controlled environment (e.g. Castanea sativa Mill.). The Temperate-zone and Mediterranean trees total biomass can increase up to 40 %, by the short-term exposure, about four months; to doubling present [CO2]. However, this stimulation declines after the first growing season in enriched CO2 environments. The studies presented in this work also show that under conditions of N deficiency, the response to elevated [CO2] of woody plants will also decrease. For example, it was observed that under middle-terra acclimation to elevated [CO2] of Quercus saber L., plants with low N availability, did not show any increase of their photosynthetic rates. This suggests that in native ecosystems with low nitrogen availability, the impact of CO2 enrichment may be insignificant on cork oak productivity. Nevertheless, elevated CO2 protects the photosynthetic apparatus against high temperatures and high irradiances in stressed or not stressed woody plants. Elevated CO2 also stimulates the activity of photoprotective mechanisms of the leaves. CO2 enrichment also reduces stomatal aperture (20 to 40 %) and therefore transpiration. This has a positive effect on the water use efficiency of woody plants; however, in stressed woody plants, the stomata responses to elevated [CO21 in the atmosphere are lower, when vapour pressure deficits between leaves and the air are high.

Il controllo degli artropodi infestanti le derrate in post-raccolta si basa principalmente sull’utilizzo di molecole chimiche di sintesi. I loro residui – spesso presenti nei prodotti alimentari finiti – hanno destato nell’opinione pubblica crescenti preoccupazioni di ordine igienico sanitario. Anche la legislazione Europea – dal canto suo – impone limiti restrittivi alla loro presenza nei cibi e al loro uso. Nell’ambito delle tecniche alternative ai pesticidi di sintesi, gli oli essenziali mostrano interessanti potenzialità per il controllo degli insetti. Il lavoro svolto in questa tesi si è proposto di valutare l’efficacia insetticida di due oli essenziali commerciali, estratti da Cannabis sativa L. e Coridothymus capitatus (L.) Rchb. f., nel controllo di Tribolium castaneum Herbst, uno degli insetti più dannosi delle derrate. La loro caratterizzazione chimica ha permesso di individuare alcune molecole che presumibilmente sono responsabili dell’azione tossica nei confronti del coleottero. I risultati ottenuti mostrano un’attività insetticida di entrambi gli oli essenziali in condizione di temperatura modificata. All’interno di un moderno protocollo di lotta integrata agli insetti, gli oli essenziali potranno effettivamente rappresentare uno tra i diversi ausili tecnici alternativi agli insetticidi di sintesi, che puntino a ridurre al minimo la presenza di residui chimici nei prodotti alimentari.

Introdução: O uso exacerbado de produtos químicos na produção de alimentos vem trazendo inúmeros problemas ambientais, econômicos e a saúde humana. Assim, é preciso buscar alternativas ao uso desses produtos. Objetivo: O objetivo do nosso estudo foi avaliar o desenvolvimento de Lactuca sativa var. crispa L. em substratos contendo diferentes concentrações de casca cozida e moída da castanha de cajú. Material e métodos: Inicialmente foi formulado um substrato composto por terra (50%), areia (30%) e esterco bovino curtido (20%). A ele foram adicionadas doses crescentes da casca cozida e moída da castanha de cajú, formando, assim, seis tratamentos (T1 – 100% do composto; T2 – 90% do composto + 10% de casca moída; T3 – 80% do composto + 20% de casca moída; T4 – 70% do composto + 30% de casca moída; T5 – 60% do composto + 40% de casca moída; T6 – 50% do composto + 50% de casca moída). Os tratamentos foram dispostos em delineamento em blocos casualizados, sendo 3 blocos e 5 réplicas por bloco cada tratamento. As leituras foram feitas semanalmente durante 16 semanas, onde foram aferidos o diâmetro do colo e altura das plantas e contabilizado o número de folhas. Os resultados obtidos foram submetidos a análise de variância seguido de teste de média (Tukey - p ≤ 0,05). Resultados: Houve diferenças significativas entre os tratamentos para as varíaveis diâmetro do colo (F = 15,7; p maior que 0,01) e número de folhas (F = 2,3; p = 0,04). Os tratamentos T1 (0,86±0,09 cm), T2 (0,86±0,16 cm), T3 (0,80±0,09 cm) e T4 (0,60±0,11 cm) foram estatisticamente iguais entre si e apresentaram médias maiores quando comparadas aos tratamentos T5 (0,20±0,10 cm) e T6 (0,01±0,08 cm). Já para a varável número de folhas, os unicos tratamentos que se diferenciaram foram o T1 do T6, sendo a maior média observada para o tratamento testemunha (6,26±1,08 folhas). Conclusão: Nossos resultados sugerem que doses mais elevadas da casca cozida e moída da castanha de caju não são indicadas para a formulação de substratos para a produção de alface.