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The complex juvenile/maturity transition during a plant's life cycle includes growth, reproduction, and senescence of its fundamental organs: leaves, flowers, and fruits. Growth and senescence of leaves, flowers, and fruits involve several genetic networks where the phytohormone ethylene plays a key role, together with other hormones, integrating different signals and allowing the onset of conditions favorable for stage progression, reproductive success and organ longevity. Changes in ethylene level, its perception, and the hormonal crosstalk directly or indirectly regulate the lifespan of plants. The present review focused on ethylene's role in the development and senescence processes in leaves, flowers and fruits, paying special attention to the complex networks of ethylene crosstalk with other hormones. Moreover, aspects with limited information have been highlighted for future research, extending our understanding on the importance of ethylene during growth and senescence and boosting future research with the aim to improve the qualitative and quantitative traits of crops.

The natural leaf senescence is the last stage of leaf development and is a highly genetically regulated process. Induced leaf senescence, instead, usually occurs in detached leaves or in plants placed in dark conditions under postharvest storage. In both cases, an oxidative burst is a typical feature of this phenomenon and includes a significant increment in reactive oxygen species (ROS), such as superoxide anion, hydrogen peroxide, hydroxyl radical, and singlet oxygen. Thus, ROS play a key role in leaf senescence process. Under normal (i.e., non-stressed) conditions, the levels of ROS are controlled and balanced by the antioxidant systems present in leaves. The leaf cells act in the defense response against the accumulation of ROS by enhancing the activity of some key enzymes such as catalase (CAT) and superoxide dismutase (SOD). In addition, the ascorbate–glutathione cycle, also known as Asada–Halliwell cycle, is the most important enzymatic antioxidant system acting in the leaf cells during senescence. The leaves are considered the main target of ROS production, and in particular, the photosynthetic apparatus and the related molecules act to support the light perception and photosynthesis activity (chlorophylls and carotenoids).

The effect of salt stress (200 mM NaCl for 28 days) on physiological characteristics of Hibiscus rosa-sinensis, such as abscisic acid (ABA) content, electrolyte leakage, and photochemical efficiency in leaves, and its influence on biomass production, anthocyanin composition, and color expression of flowers were evaluated. Salinity significantly increased electrolyte leakage and ABA content in leaves and reduced the flower fresh weight. Chlorophyll fluorescence parameters were lower in salt stress condition, compared to control. Moreover, salt stress negatively affected the content of anthocyanins (mainly cyanidin-3-sophoroside), which resulted in a visually perceptible loss of color. The detailed anthocyanin composition monitored by HPLC-DAD-MS and the color variations by digital image analysis due to salt stress showed that the effect was more noticeable at the basal portion of petals. A forward stepwise multiple regression was performed for predicting the content of anthocyanins from appearance characteristics obtained by image analysis, reaching R-square values up to 0.90.

Isoprene strengthens thylakoid membranes and scavenges stress-induced oxidative species. The idea that isoprene production might also influence isoprenoid and phenylpropanoid pathways under stress conditions was tested. We used transgenic tobacco to compare physiological and biochemical traits of isoprene-emitting (IE) and non-emitting (NE) plants exposed to severe drought and subsequent re-watering. Photosynthesis was less affected by drought in IE than in NE plants, and higher rates were also observed in IE than in NE plants recovering from drought. Isoprene emission was stimulated by mild drought. Under severe drought, isoprene emission declined, and levels of non-volatile isoprenoids, specifically de-epoxidated xanthophylls and abscisic acid (ABA), were higher in IE than in NE plants. Soluble sugars and phenylpropanoids were also higher in IE plants. After re-watering, IE plants maintained higher levels of metabolites, but isoprene emission was again higher than in unstressed plants. We suggest that isoprene production in transgenic tobacco triggered different responses, depending upon drought severity. Under drought, the observed trade-off between isoprene and non-volatile isoprenoids suggests that in IE plants isoprene acts as a short-term protectant, whereas non-volatile isoprenoids protect against severe, long-term damage. After drought, it is suggested that the capacity to emit isoprene might up-regulate production of non-volatile isoprenoids and phenylpropanoids, which may further protect IE leaves.

Lycopus lucidus Turcz. ex Benth. var. hirtus Regel (Lamiaceae), a neophyte native to Asia, is recorded for the first time in Europe. A naturalized population was discovered in the Milan railway area (Italy). Diagnostic characters and an updated identification key for the genus Lycopus in Europe are presented. Furthermore, the invasive status and the possible means of introduction are discussed.

Lemon balm ( Melissa officinalis , L.; Lamiaceae) was exposed to realistic ozone (O 3 ) dosages (80 ppb for 5 h), because high background levels of O 3 are considered to be as harmful as episodic O 3 regimes. Temporal alterations of different ecophysiological, biochemical and structural parameters were investigated in order to test if this species can be considered as an O 3 -bioindicator regarding changes in background concentrations. At the end of ozone exposure, the plants did not exhibit any visible foliar symptoms, as only at microscopic level a small number of dead cells were found. Photosynthetic processes, however, were significantly affected. During and after the treatment, ozone induced a reduction in CO 2 fixation capacity (up to 52% after 12 h from the beginning of the treatment) due to mesophyllic limitations. Intercellular CO 2 concentration significantly increased in comparison to controls (+90% at the end of the post-fumigation period). Furthermore impairment of carboxylation efficiency (−71% at the end of the post-fumigation period compared to controls in filtered air) and membrane damage in terms of integrity (as demonstrated by a significant rise in solute leakage) were observed. A regulatory adjustment of photosynthetic processes was highlighted during the post-fumigation period by the higher values of qNP and (1-q P ) and therefore suggests a tendency to reduce the light energy used in photochemistry at the expense of the capacity to dissipate the excess as excitation energy. In addition, the chlorophyll a / b ratio and the de-epoxidation index increased, showing a rearrangement of the pigment composition of the photosynthetic apparatus and a marked activation of photoprotective mechanisms.

Stories of violence and oppression from classical mythology and fairy tales are redeployed in two novels by Atwood (1985) and Atkinson (1997) as archetypal pre-texts that impact on plot and narrative process. Although they are very different in genre and theme, both novels present first-person female narrators who are trapped in a claustrophobic present, and pose the question of the extent to which a story can be told from within the boundaries traced by myth, fairy tales and quasi-mythical literary texts. Clearly indebted to Orwell’s Nineteen Eighty-Four, The Handmaid’s Tale depicts a dystopian world where women live segregated by a male regime. References to the tale of Little Red Cap, classical myths and ceremonies are embedded in the text and reveal the story as a narrative that replicates the oppressive structure in which the female protagonist is imprisoned. On the other hand, Atkinson’s Human Croquet is a metafictional family saga where Ovidian imagery, fairy tales and Shakespearean texts shape throughout the hyperliterate narrator’s vision of the world, leaving her (and the reader) with a sense of inescapable and at times threatening déjà-vu. Besides the connections between myths of violence and plots, the essay will highlight the structuring principle of repetition, which in both works emerges as a form of epistemic violence that tragically questions or diminishes the narrative voice.

The habitat requirements of a species are the resources, conditions and space required for survival and reproduction. The habitat requirements of butterflies have been well studied, but the extent to which individuals within a species and between species utilise and share the habitat is poorly known.In a butterfly assemblage in northern Italy, we found that adults from 30 species avoid deciduous high‐density forests and their ecotones, and they were positively related to open areas and their ecotones. Besides these common features, five groups of species can be discriminated in relation to a gradient from open area to forest, and species within groups were not equally specialised, as observed from a bipartite network analysis. In particular, some species appeared to be specialised and others appeared to be generalist, suggesting a nested pattern of resource use, rather than a clustered pattern in which each species uses a different subset of habitat types.The degree of variation in specialisation among species varied with the number of species falling in each group. Thus, an increased number of species, and thus possibly competition, is more likely to promote the co‐occurrence of generalist and specialised species (nested patterns) rather than an increased niche segregation among species.Ascertaining how species overlap their habitat use at a local scale can be relevant for conservation purposes, because specialised populations are potentially more susceptible to network distortions.

Ozone (O3) and salinity are usually tested as combined factors on plant performance. However, the response to a single episode of O3 in plants already stressed by an excess of NaCl as occurs in the natural environment has never been investigated, but is important given that it is commonly experienced in Mediterranean areas. Three-year-old Quercus ilex L. (holm oak) saplings were exposed to salinity (150 mM NaCl, 15 days), and the effect on photosynthesis, hydric relations and ion partitioning was evaluated (Experiment I). In Experiment II, salt-treated saplings were exposed to 80 nl l-1 of O3 for 5 h, which is a realistic dose in a Mediterranean environment. Gas exchanges, chlorophyll fluorescence and antioxidant systems were characterized to test whether the salt-induced stomatal closure limited O3 uptake and stress or whether the pollutant represents an additional stressor for plants. Salt-dependent stomatal closure depressed the photosynthetic process (-71.6% of light-saturated rate of photosynthesis (A380)) and strongly enhanced the dissipation of energy via the xanthophyll cycle. However, salt-treated plants had higher values of net assimilation rate/stomatal conductance (A/gs) than the controls, which was attributable to a greater mesophyll conductance gm/gs and carboxylation efficiency (higher gm/maximal rate of Rubisco carboxylation (Vcmax)), thus suggesting no damage to chloroplasts. O3 did not exacerbate the effect of salinity on photosynthesis, however a general enhancement of the Halliwell-Asada cycle was necessary to counteract the O3-triggered oxidative stress. Despite the 79.4% gs reduction in salt-stressed plants, which strongly limited the O3 uptake, a single peak in the air pollutant led to an additional burden for the antioxidant system when plants had been previously subjected to salinity.

Among various contaminants, ozone (O3) is considered the most ubiquitous and phytotoxic atmospheric pollutant in industrialized and developing countries. It causes extensive risks for plant life, in terms of survival and productivity of wild and cultivated species. Plant response to O3 resembles the biotic defense reactions and includes two steps: the first is a biphasic oxidative burst with a massive, rapid, and transient increase in apoplastic reactive oxygen species (ROS) production; the second is the induction of the hypersensitive response (HR) and systemic acquired resistance (SAR). In particular, the acute O3 exposure (high concentrations for a few hours) results in the activation of programmed cell death (PCD) response that interacts with the synthesis of several hormones and other signaling molecules. The cross talk among all these molecules and their complex and interconnected signaling pathways are more important to determine (1) the initiation, propagation, and containment of O3-induced cell death, (2) the degree of the sensitivity of plants to this contaminant, and (3) the regulatory potential that plants have to promptly respond to oxidative stress. The present chapter reviews the role of phytohormones (such as ethylene, abscisic acid, gibberellins, auxins, and cytokinins) and other signaling molecules (such as salicylic and jasmonic acids, proline, and brassinosteroids), as well as their synergistic and antagonistic effects, in the complex signaling pathway involved in plant responses to O3 stress.

The response of plants to salt stress involves dynamic changes in growth and signaling leading to successful adaptation or death. To elucidate how these opposed events are coordinated we identified a salt-tolerant (obesifruticosa) and a salt-sensitive (aestiva) Antirrhinum majus mutants using shoots as sensitive indicator of stress magnitude. A series of physiological tests were performed that compared the response after 6 h and 3 days of these contrasting mutants grown in agar under a single (200 mM) NaCl concentration, including shoot area, root length, relative water content, plant height, and overall biomass accumulation. Additional measurements of ABA content, chlorophyll degradation, ethylene production, net photosynthesis rates and Na+, K+, Ca2+, and Mg2+ content were also reported. RNA-seq analysis was performed on the two mutants after 6 h and 3 days under 200 mM NaCl. A total of 9199 transcripts were found to be differentially expressed in response to NaCl treatment in the two mutants. A large collection of known genes, including MAPKs, CDKs, CDPKs, CIPKs, various transcription factors, various ion transport proteins, and various genes involved in ABA and ethylene signaling pathways were described in detail that displayed differential expression profiles. Overall these data provided evidences of a putative osmotic tolerance sensing and signaling mechanism through a better integration and transduction of environmental cues into growth programs. The reprogramming of calcium-signaling components, generates specific stress signatures affecting differentially the salinity tolerance traits, such as tissue tolerance and anion exclusion. Interestingly, the hormones ABA and ethylene may action as a positive regulators of salt acclimation by the modulation of their signal transduction pathway.

Solanum lycopersicum L. (tomato) is a very important fruit vegetable with high economic importance and nutritional impact on the consumers worldwide. Moreover, tomato fruits are an important source of nutraceutical compounds. This work describes the physiological diversity affecting the ripening process that yields variation in fruit pigmentation with regard to anthocyanins compounds for one non-anthocyanin-accumulating (Ailsa Craig) and two anthocyanin-accumulating tomato genotypes (anthocyanin fruit type, low pigment accumulation, and Sun Black, high pigment accumulation). Using tomato fruits obtained by traditional breeding the present study reported modified hormone equilibrium at different ripening stages. This phenomenon can be considered as a consequence of the different pattern in the anthocyanins accumulation in fruits. Moreover, the fruit genotype showing the highest pigment accumulation appear more firm at the commercial stage. Overall, these results showed the considerable potential of exploiting natural genetic diversity to obtain tomatoes with higher levels of anthocyanins, and different quality traits such as colour and firmness.

There is a tremendous growing interest both in various industrial sectors and among people worldwide, towards the use of natural compounds from plant origin. The natural compounds obtained from plants have been more and more employed by cosmetic, food and pharmaceutical industries and could represent potential alternatives to synthetic chemicals. In the Lamiaceae family there are herbs with enormous socio-economic value, including several species of horticultural and ornamental interest, many used as culinary herbs, and with diversified industrial applications essentially due to their high content in valuable phenolic compounds. This review focuses on the wide spectrum of bioactive phenolic compounds in several species in the Lamiaceae , which possess known pharmacological properties and are used by humans for therapeutic purposes. It also reports other challenging and innovative industrial applications of these compounds as potential alternatives to conventional synthetic chemicals, because natural phenols would have lesser environmental and human health impacts than most of the conventional ingredients used in cosmetic, pesticides and food additives-preservatives industries. Finally, the review considers how an enhanced understanding of the effects of elicitation could be applied to increase and/or modify tissue content of active principles. Chemical or physical elicitors can activate the stress-signaling pathways leading to enhance the content of bioactive secondary metabolites, thus representing a new perspective for sustainable production of industrial crops.

Highlight Pathway analysis suggests that identified temporal and spatial transcriptomic changes associated with senescence of the short-lived hibiscus flower are regulated by light/circadian clock-, aquaporin-, cell wall-, and calcium-related gene families., Flowers are complex systems whose vegetative and sexual structures initiate and die in a synchronous manner. The rapidity of this process varies widely in flowers, with some lasting for months while others such as Hibiscus rosa-sinensis survive for only a day. The genetic regulation underlying these differences is unclear. To identify key genes and pathways that coordinate floral organ senescence of ephemeral flowers, we identified transcripts in H. rosa-sinensis floral organs by 454 sequencing. During development, 2053 transcripts increased and 2135 decreased significantly in abundance. The senescence of the flower was associated with increased abundance of many hydrolytic genes, including aspartic and cysteine proteases, vacuolar processing enzymes, and nucleases. Pathway analysis suggested that transcripts altering significantly in abundance were enriched in functions related to cell wall-, aquaporin-, light/circadian clock-, autophagy-, and calcium-related genes. Finding enrichment in light/circadian clock-related genes fits well with the observation that hibiscus floral development is highly synchronized with light and the hypothesis that ageing/senescence of the flower is orchestrated by a molecular clock. Further study of these genes will provide novel insight into how the molecular clock is able to regulate the timing of programmed cell death in tissues.

Il romanzo in versi The Emperor's Babe (2001) di Bernardine Evaristo racconta la storia di Zuleika, figlia di due immigrati dalla Nubia, che vive nell'antica Londra romana all'inizio del III sec. d.C. Evaristo usa sia fonti classiche – poesia, proverbi, motti latini, miti, e cultura materiale – sia moderne, come Oscar Wilde, la cui concezione della storia informa l'intento revisionista del romanzo. L'articolo intende esaminare il ruolo delle citazioni e degli echi intertestuali nello sviluppo della trama e nella dialettica tra passato e presente. Se apparentemente essi contribuiscono a ricreare lo sfondo culturale antico, a un livello più profondo producono scarti ironici o effetti parodistici nel contrasto tra toni, stili e situazioni. Inoltre, in considerazione della voce narrante, gendered e subalterna, essi si rivelano un aspetto cruciale di quell'intento di riscrittura della storia che Evaristo compie in questo romanzo: sovrapponendo la Londra post-imperiale e multiculturale odierna alla città romana, The Emperor's Babe sovverte il mito della nazione alle sue origini. Bernardine Evaristo's novel in verse The Emperor's Babe (2001) features the story of Zuleika, the daughter of Nubian immigrants, who lives in Roman London at the beginning of the third century A.D.. Evaristo's sources are both classical – Latin poetry, proverbs, mottos, myths, as well as material culture – and modern – for example, Oscar Wilde's perspective on history informs the revisionist intent of the novel. This article aims to examine the role of quotations and intertextual echoes in the development of the storyline and in the dialectic between past and present. If apparently they contribute to the recreation of the ancient cultural background, at a deeper level, they also engender ironic tensions and parodic effects through discrepancies in tone, style and narrative situations. Moreover, in relation to the protagonist's gendered and subaltern position, quotations and other references are a crucial aspect of Evaristo's rewriting of history: by mapping today's post-imperial and multicultural London on to the Roman city, The Emperor's Babe subverts the myth of the nation at its roots.

Senescence is genetically controlled and activated in mature tissues during aging. However, immature plant tissues also display senescence-like symptoms when continuously exposed to adverse energy-depleting conditions. We used detached dark-held immature inflorescences of Arabidopsis (Arabidopsis thaliana) to understand the metabolic reprogramming occurring in immature tissues transitioning from rapid growth to precocious senescence. Macroscopic growth of the detached inflorescences rapidly ceased upon placement in water in the dark at 21°C. Inflorescences were completely degreened by 120 h of dark incubation and by 24 h had already lost 24% of their chlorophyll and 34% of their protein content. Comparative transcriptome profiling at 24 h revealed that inflorescence response at 24 h had a large carbon-deprivation component. Genes that positively regulate developmental senescence (ARABIDOPSIS NAC DOMAIN CONTAINING PROTEIN92) and shade-avoidance syndrome (PHYTOCHROME INTERACTING FACTOR4 [PIF4] and PIF5) were up-regulated within 24 h. Mutations in these genes delayed degreening of the inflorescences. Their up-regulation was suppressed in dark-held inflorescences by glucose treatment, which promoted macroscopic growth and development and inhibited degreening of the inflorescences. Detached inflorescences held in the dark for 4 d were still able to reinitiate development to produce siliques upon being brought out to the light, indicating that the transcriptional reprogramming at 24 h was adaptive and reversible. Our results suggest that the response of detached immature tissues to dark storage involves interactions between carbohydrate status sensing and light deprivation signaling and that the dark-adaptive response of the tissues appears to utilize some of the same key regulators as developmental senescence.

To study the diet of 2 coastal spawning groups of Illex argentinus, we analyzed the stomach contents of 3645 specimens (10 to 36 cm in mantle length). More than half (58%) of observed stomachs were empty. There were no differences in the prey consumed between specimens of different sex and maturity stages. Additionally, no differences were observed in the diet among individuals belonging to either the summer or spring spawning groups. The most frequent prey item was fishes (0.79 frequency of occurrence), followed by cephalopods (0.18) and lastly by crustaceans (0.09). The seasonal variation of empty stomach frequency and the mean stomach fullness revealed that squids fed more actively in spring and summer and mainly preyed upon small pelagic fishes.

Nest defence is a common form of parental care employed by birds to improve the survival of their offspring. Theory predicts that parents should adjust their nest defence according to the value of the brood at stake, defending more intensively broods with high survival and reproductive prospects. We evaluated the influence of offspring number, offspring age, laying date and parent sex on nest-defence intensity (NDI) of the Imperial Shag Phalacrocorax atriceps, a sexually dimorphic seabird with seasonal decline in offspring survival and very limited renesting potential. We also evaluated whether NDI was correlated within pairs and whether NDI of both members of the pair was correlated with incubation and breeding success. To elicit defensive behaviour, we simulated predation attempts using a Kelp Gull Larus dominicanus model. As predicted by theory, NDI was positively correlated with the number of offspring in the nest and offspring age. NDI during chick rearing was higher than that at early and late incubation, while no differences were found between incubation stages. Contrary to our prediction, we did not find differences in NDI according to laying date. NDI for males was higher than females, while NDI was also positively correlated within pairs. NDI was not statistically related to incubation or breeding success. These results suggest that other factors, such as laying date or parental quality and age, play a much larger role in determining the outcome and productivity of a nesting attempt. Our results provide partial support for parental investment theory; while parental defence increased with brood value according to offspring number and age, parental defence was not related to laying date, a factor strongly affecting offspring survival and recruitment probabilities in this species.

Harvested plant organs such as heads of broccoli (Brassica oleracea L. var. italica) experience a range of stresses that can lead to premature reduction in quality and eventual senescence. Understanding plant responses to stress may open up novel opportunities to extend postharvest life. One of the first stresses experienced by harvested organs is likely to be water deficit stress since severance of the vascular system halts the normal flux of water into the tissue. For broccoli branchlets with their cut ends held in water, transcriptome analysis based on hybridization of broccoli floret mRNA to a heterologous Arabidopsis microarray revealed that the transcript abundance of 431 genes reliably changed within 48 h of harvest. Of these, transcripts of 146 genes increased and 34 genes decreased in abundance by 3-fold or more. When broccoli branchlets were held with their cut ends in PEG solution they showed a five-fold reduction in branchlet fresh weight at 48 h compared with controls. Holding branchlets in humid air resulted in an intermediate loss in fresh weight. This PEG-induced high water deficit stress further enhanced the mRNA accumulation of only a small percentage (14%) of the harvest-induced genes. However, for the group of 110 genes that responded to the PEG treatment, the transcript abundance of 90 correlated with the extent of water deficit. Another group (18% of harvest-induced genes) was repressed under more severe water stress, indicating that harvest and water-deficit stress have opposite effects on the transcript abundance of some genes. Gene cluster analysis showed that these genes included a cluster associated with sugar metabolism that may be responding to reduced sugar content. Genes required for photosynthesis and protein translation were also down-regulated by severe water stress, but were unaffected in the water control 48 h after harvest. We conclude that water deficit stress is not the primary driver of harvest-related transcriptome changes in the florets of a detached broccoli head. The findings suggest that the molecular responses to sugar depletion and water deficit stress are not simply additive and appear to be interactive in the harvested tissue.

A comparative study on functional leaf treats and the diurnal dynamics of photosynthetic processes was conducted on 2-year-old potted plants of two grape (Vitis vinifera L.) varieties (Aleatico, ALE, and Trebbiano giallo, TRE), exposed under controlled conditions to realistic concentrations of the pollutant gas ozone (80 ppb for 5 h day(-1), 8:00-13:00 h, + 40 ppb for 5 h day(-1), 13:00-18:00 h). At constitutive levels, the morphological functional traits of TRE improved leaf resistance to gas exchange, suggesting that TRE is characterized by a potential high degree of tolerance to ozone. At the end of the treatment, both varieties showed typical visible injuries on fully expanded leaves and a marked alteration in the diurnal pattern of photosynthetic activity. This was mainly due to a decreased stomatal conductance (-27 and -29% in ALE and TRE, in terms of daily values in comparison to controls) and to a reduced mesophyllic functioning (+33 and +16% of the intercellular carbon dioxide concentration). Although the genotypic variability of grape regulates the response to oxidative stress, similar detoxification processes were activated, such as an increased content of total carotenoids (+64 and +30%, in ALE and TRE), enhanced efficiency of thermal energy dissipation within photosystem II (+32 and +20%) closely correlated with the increased de-epoxidation index (+26 and +22%) and variations in content of some osmolytes. In summary, we can conclude that: the daily photosynthetic performance of grapevine leaves was affected by a realistic exposure to ozone. In addition, the gas exchange and chlorophyll a fluorescence measurements revealed a different quali-quantitative response in the two varieties. The genotypic variability of V. vinifera and the functional leaf traits would seem to regulate the acclimatory response to oxidative stress and the degree of tolerance to ozone. Similar photoprotective mechanisms were activated in the two varieties, though to a different extent.

a b s t r a c t Flowering or foliage potted plants are ornamental items usually grown in greenhouses under optimal growing conditions. Cultivation in protected environments allows for rapid growth and high quality characteristics. When plants reach the desired commercial size they can be transferred to hardening greenhouses or directly sent to the distribution chain. The growing and post-production conditions such as storage and transportation can have very deleterious effects on the ornamental quality of plants. The major post-production disorders are bud and flower abscission in flowering potted plants or leaf abscission or yellowing in foliage potted plants. On the other hand, the ornamental quality of potted plants is extremely important and depends on the number and colour of flowers or leaves, flower, leaf and plant longevity. The presence of flowers on flowering potted plants depends on flower longevity and turnover. The colour and size of leaves of foliage potted plants is linked to pre- and post-production environmental conditions. The post-production quality losses of flowering potted plants can be mainly ascribed to natural flower senescence. This phenomenon is highly regulated by plant hormones such as ethylene and abscisic acid, but the post-production environment can dramatically influence plant hormone equilibrium. Quality losses of foliage potted plants are mainly due to leaf senescence usually associated with inadequate acclimatization from the production area to the post-production chain. © 2014 Elsevier B.V. All rights reserved.

Ethylene is a plant hormone involved in several physiological processes and regulates the plant development during the whole life. Stressful conditions usually activate ethylene biosynthesis and signalling in plants. The availability of nutrients, shortage or excess, influences plant metabolism and ethylene plays an important role in plant adaptation under suboptimal conditions. Among the plant nutrients, the nitrogen (N) is one the most important mineral element required for plant growth and development. The availability of N significantly influences plant metabolism, including ethylene biology. The interaction between ethylene and N affects several physiological process such as leaf gas exchanges, roots architecture, leaf, fruits and flowers development. Low plant N use efficiency leads to N loss and N deprivation, which affect ethylene biosynthesis and tissues sensitivity, inducing cell damage and ultimately lysis. Plants may respond differently to N availability balancing ethylene production through its signalling network. This review discusses the recent advances in the interaction between N availability and ethylene at whole plant and different organ levels, and explores how N availability induces ethylene biology and plant responses. Exogenously applied ethylene seems to cope the stress conditions and improves plant physiological performance. This can be explained considering the expression of ethylene biosynthesis and signalling genes under different N availability. A greater understanding of the regulation of N by means of ethylene modulation may help to increase N use efficiency and directly influence crop productivity under conditions of limited N availability, leading to positive effects on the environment. Moreover, efforts should be focused on the effect of N deficiency or excess in fruit trees, where ethylene can have detrimental effects especially during postharvest.

Agricultural growing practices have been evolving towards organic, sustainable or environmental friendly systems. The aim of modern agriculture is to reduce inputs without reducing the yield and quality. These goals can be achieved by breeding programmes but would be species specific and time consuming. The identification of organic molecules able to activate plant metabolism may allow an improvement in plant performance in a short period of time and in a cheaper way. Biostimulants are plant extracts and contain a wide range of bioactive compounds that are mostly still unknown. These products are usually able to improve the nutrient use efficiency of the plant and enhance tolerance to biotic and abiotic stresses. In this review, the state of the art and future prospects for biostimulants are reported and discussed. Moreover, particular attention has been paid to intensive agricultural systems such as horticultural and floricultural crops. In vegetables, the application of biostimulants allowed a reduction...

Twenty-one adult male chamois were radio-tracked from February 2000 to November 2002, in Gran Paradiso National Park, Graie Alps, Italy. The median size of annual home ranges was 70 ha (Kernel 95%). Home range size in the warm months was significantly much larger than in the cold period. In the summer, all males moved to greater altitudes (about 2200 m a.s.l.), whereas they lived at ca 1950 m a.s.l. in the winter. Two strategies of space use were detected: 76.2% of male chamois were residents (i.e., overlapping or contiguous summer and winter home ranges), whereas the others were seasonal migrants (i.e. well separate summer and winter home ranges). In the warm months, the home ranges of migrants were significantly much larger and at higher altitudes than those of residents. Resident males may gain a reproductive advantage over migrants in years with a snow cover during the rut (i.e. when females descend to low altitudes, where resident males live), whereas migrants could be favoured in ruts with little or...