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Evaluation of two green composts for peat substitution in geranium ( Pelargonium zonale L.) cultivation: Effect on plant growth, quality, nutrition, and photosynthesis
No full textPeat is the most representative component in the preparation of growing media used in horticulture. However, environmental issues and increased production costs, related to peat extraction and commercialization, are stimulating the use of new materials and technologies as alternatives to peat-based growing media. Among other locally-produced materials, green compost is one of the most promising alternatives for peat substitution although its variability in terms of physico-chemical characteristics represents the main constraint. In the present work, two composts, differing in terms of the initial composting raw materials, were evaluated for peat substitution and their influence on plant growth and quality, nutrient and water uptake, and gaseous exchange activity. A bedding plant (geranium), cultivated in an intensive growing system, was chosen as the test plant and 100% peat as the control. During the greenhouse experiment, plants were grown in five different growing media, i.e. only peat, 30% and 50% peat volume replaced by the two composts. Growing medium characteristics, plant growth and biometric parameters, water and nutrient uptake, and gaseous exchange activity were evaluated as crop performance indicators. The green compost derived from mixed raw material negatively influenced plant nutrition and photosynthesis, thus significantly reducing plant biomass accumulation and quality. The green compost derived from selected material was found to be a valuable growing medium for peat substitution. This thus supports the widespread opinion that high-quality compost can be produced through the selection of
composting material
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
La pigmentazione nel fiore di Lilium
No full textIl Lilium costituisce una delle colture più importanti sia nel mercato floricolo italiano che in quello internazionale. La sua elevata popolarità è dovuta principalmente alle sue caratteristiche ornamentali quali il colore dei fiori e delle foglie, l’altezza degli steli, la forma delle infiorescenze e l’architettura della pianta, che rendono il Lilium una delle colture più apprezzate e conosciute in tutto il mondo.
Spesso accade che la qualità della pianta sia influenzata dalla stagione di coltivazione, derivando una peggiore qualità per le coltivazioni autunnali e invernali rispetto a quelle estive, riconoscibile dal precoce appassimento e abscissione dei tepali, dall’ingiallimento fogliare causato in molti casi dalle condizioni di oscurità e di basse temperature, dall’aborto o incompleta apertura dei fiori apicali, e dalla diminuzione di brillantezza e attenuazione dell’intensità del colore dei tepali, dovuta ad una minore radiazione solare. Questo fenomeno è più evidente nei fiori di Lilium con tonalità rosse, rosa e arancio ed è prevalentemente dovuto ad una ridotta sintesi di antociani.
La biosintesi di antociani è indotta da diversi fattori, quali ad esempio l’elevata escursione termica giornaliera o la stessa radiazione solare. Per riuscire ad aumentare la biosintesi di antociani nei prodotti vegetali si possono usare diverse strategie, generalmente impiegate per migliorare l’aspetto di prodotti orto-frutticoli; buoni risultati sono stati ottenuti su melanzana, melone, pomodoro e mele con la somministrazione di solfato potassico per via fogliare, quando le basse escursioni termiche determinano una scarsa colorazione dei frutti. Le concimazioni a base di azoto e potassio hanno portato un effetto positivo su diverse cultivars di piante da fiore, tra cui il gladiolo (Accati et al., 1994; DeVecchi e Barni, 1997). Tra i vari trattamenti possibili per il miglioramento dell’apertura dei fiori e il prolungamento della durata in vaso di molte specie è noto l’utilizzo degli zuccheri (in particolare del saccarosio) nell’acqua di conservazione; in alcuni casi un ulteriore effetto positivo osservato è stato l’aumento della concentrazione delle antocianine nei petali, e quindi la comparsa di colorazioni a tinte più forti. Recentemente sono apparsi dei risultati interessanti sull’ aumento della concentrazione delle antocianine in uva (cv Merlot) trattata con un nuovo prodotto acibenzolar-s-methyl (Bion) (Iriti et al., 2004),
Alla luce di tutte queste conoscenze presso l’Istituto Sperimentale per la Floricoltura (ISF) di Pescia sono state condotte prove sperimentali sul Lilium cresciuto in stagione sfavorevole (autunno/invernale) per migliorare la colorazione dei fiori, valutare la longevità di steli Lilium, valutare la percentuale di aborti.
Misurazione dei parametri relativi al colore impiegando un particolare e nuovo apparecchio, quale lo spettrometro per immagini o scanner spettrale VIS-NIR
Una nuova metodologia è stata adottata per la misurazione dei parametri relativi al colore, che ha previsto l’impiego; di un particolare apparecchio, quale lo spettrometro per immagini o scanner spettrale VIS-NIR, normalmente impiegato in altri processi industriali.
L’utilizzo di questa tecnica consente di ridurre i tempi di misurazione del colore con risposte immediate e molto accurate.
I risultati ottenuti indicano che i trattamenti effettuati migliorano la qualità dei fiori esaminat
Bat guano and Nettle slurry (Urtica dioica L.) used as biostimulants on Delosperma cooperi and Sedum rubrotinctum plants
No full textThe aim of the experiment was to evaluate the use and influence of Bat guano and Nettle slurry on the growth, flowering and mineral absorption of Delosperma cooperi and Sedum rubrotinctum plants. The 3 experimental groups in cultivation were: (1) group without biostimulants (CTRL), irrigated with water and previously fertilized substrate; (2) group Bat guano (BG) and fertilized substrate; (3) group Nettle slurry (Urtica dioica L.) (UD) and fertilized substrate. Treatments with Nettle slurry and Bat guano resulted in a significant improvement in the growth and flowering characteristics of Delosperma cooperi and Sedum rubrotinctum. The test showed in fact a significant increase in the agronomic parameters analysed in plants treated with Bat guano and Nettle slurry. In fact, all the plants treated with (BG and UD) showed a significant increase in the number of leave, flowers and inflorescences, in the vegetative, radical and inflorescence weight, in the flowering time. The test also resulted in an increase in the NPK mineral absorption and chlorophyll content of plants treated with bat guano and nettle slurry.Interesting aspects that make Bat guano and Nettle slurry valid alternatives to be used as plant biostimulants, when the plants are subjected to biotic and abiotic stresses, in particular transplant, water and salt stress
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Trichoderma spp. in innovative substrates for ornamental plants
No full textTrichoderma spp. are free-living fungi commonly widespread in soil and root ecosystems. Recent discoveries show them as opportunistic, avirulent plant symbionts as well as parasites of other fungi. Some strains establish robust and long-lasting colonization of roots by entering into the first epidermal layers. Root colonization frequently results in enhancing of growth and development, crop productivity or induction of resistance to abiotic and biotic factors.
Peat, mainly imported from the northern and eastern European regions, is the basic constituent of organic substrates commonly utilized in the cultivation of ornamental plants in pots or in benches. During the past few years, the supply of the peat is hampered by environmental and economical constraints. Recently, the European Commission decided to exclude all substrates containing peat from the release of the Community Eco-Label Mark. In this optic the need to reduce peat in ornamental substrates devised great attention and resulted in pressing and increasing research activity to set up new and innovative substrates for ornamental market.
The aim of the present PhD thesis is to select beneficial fungi belonging to Trichoderma genus, to be add as soil inoculants, in order to develop an innovative, economical and suitable substrate alternative to peat for cultivation of seed plants (Limonium sinuatum and Cupressus sempervirens) and of acidophilus species (Camellia japonica) of ornamental interest. The activity involved the selection of Trichoderma spp. isolates for their ability to grow in the roots, as endophytes, or in the rhizosphere, to protect plants against plant pathogens or to act as plant growth promoters. The preliminary screening for endophytism resulted in 10 interesting isolates (out of 162) for Limonium sinuatum, 9 (out of 162) for Cupressus sempervirens and 8 (out of 202) for Camellia japonica. From following rounds of screening, three Trichoderma isolates, among which T. asperellum 2046 in common for all the species, confirmed the best endophytic performance and improved growth.
The antagonistic activity of these selected strains, against fungal plant pathogens as Sclerotinia sclerotiorum, S. minor, Colletotrichum gleospoiroides and Rhizoctonia solani, has been evaluated in order to analyse if these isolates could be considered good beneficial fungi. In addition. T2046 was evaluated in biocontrol experiments on Limonium, against S. sclerotiorum and S. minor with mycoparasistim investigated as principal mechanisms.
Encouraging results herewith obtained, suggest that T. asperellum 2046 could be taken into account as bioactive ingredient of new biopesticide and/or biofertilizer to be used as inoculant for innovative substrates for ornamental plants
Effect of Glomus mosseae inoculation on growth and flowering improvement of Chamaecereus sylvestrii and Mammillaria laui
No full textThe aim of the experiment was to study how Glomus mosseae influences the growth and flowering of cacti such as Mammillaria laui and Chamaecereus sylvestrii. The experimental theses have been: (1) soil inoculated with Glomus mosseae and fertilized; (2) soil without Glomus mosseae, irrigated with water and fertilizer (control). The test showed a significant increase in the agronomic parameters analysed in plants treated with Glomus mosseae. In fact, all cactus plants treated with endomycorriza showed a significant increase in the vegetative and radical part of the plants, in the number of flowers per plant and in the duration of flowering. This endomycorriza can therefore also have beneficial effects on plants that are slow to grow and prolong the life of their flowers, beautiful to see but that normally short-lived. Further studies will be done on the use of mycorrhiza on cacti and succulents and the influence on resistance to biotic and abiotic stress of different typologies
Possible use of Inula viscosa (Dittrichia viscosa L.) for biostimulation of Oscularia deltoides and Corpuscolaria lehmanii plants and protection against Aphis nerii
No full textIn this study the possibility of using liquid Inula viscosa (Dittrichia viscosa L.) to improve the growth and quality of Oscularia deltoides and Corpuscolaria lehmanii plants and protection against Aphis nerii was evaluated. The 3 experimental groups in cultivation were: i) group without the use of Inula viscosa liquid macerate (CTRL), irrigated with water and previously fertilised substrate; ii) group treated with 1% of Inula viscosa liquid obtained from flowers (leaf spraying and soil irrigation), previously fertilized substrate (INU1); iii) group treated with 1% of Inula viscosa liquid obtained from leaves and stems (leaf spraying and soil irrigation), previously fertilized substrate (INU2). The test showed a significant increase in the agronomic parameters analyzed in plants treated with liquid Inula viscosa. In fact, all plants treated with Inula showed a significant increase in plant height, leaves number, vegetative and roots weight, branches and flowers number and flowering time in both Corpuscolaria lehmanii and Oscularia deltoides. An evaluation was also made of the number of individuals of Aphis nerii present on the plants of Corpuscolaria lehmanii and Oscularia deltoides to assess whether the macerate of Inula can be used for the control of these insects. The GC-MS analysis of active fractions strongly suggested costic acid as the compound responsible for contact toxicity against Aphis nerii. Probably in the plant treated with Inula viscosa there is an induction of the defense mechanisms that lead to greater resistance to biotic and abiotic stresses. The application of Inula macerate also improves the plant's defences against attacks by fungal pathogens and insects. Very interesting aspects, especially in view of a possible reduction of fertilizers and synthetic plant protection products
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