1,721,020 research outputs found
Analisi del trascrittoma durante lo sviluppo e la senescenza dei fiori di Hibiscus rosa-sinensis L.
No full textLa senescenza dei fiori è un processo programmato e altamente regolato a livello genetico. I tessuti fiorali durante la senescenza subiscono dei profondi cambiamenti che coinvolgono diversi processi fisiologici e biochimici. Per approfondire le basi genetiche che regolano questi processi è stato effettuato un’analisi del trascrittoma dei fiori di ibisco (Hibiscus rosa-sinensis L.). I fiori sono stati campionati allo stadio di gemma e fiore aperto/senescente al fine di ottenere il maggior numero di geni possibili coinvolto nel processo d’invecchiamento dei fiori. Dai campioni è stato estratto l’RNA totale e utilizzato per la costruzione di una libreria a doppia elica di cDNA. Le librerie sono state sequenziate utilizzando la tecnologia 454 al fine di ottenere sequenze lunghe da poter facilmente annotare. Il sequenziamento ha prodotto 30988 geni totali tra gemma e fiori aperti/senescenti. In particolare, nella gemma sono stati isolati 23058 geni e nei fiori aperti/senescenti 18102. I geni comuni ai due stadi sono stati 10172, mentre 12866 erano solo espressi nelle gemme e 7930 solo nei fiori aperti senescenti.
La lunghezza media delle sequenze ottenute è stata di 319, 2 bp, con una media di 339,11 bp nelle gemme e 296,4 bp nei fiori aperti/senescenti.
L’analisi del profilo di espressione ha individuato una totale di 4.188 geni differenzialmente espressi tra la gemma e il fiore parzialmente senescente, tra i quali 2.053 sono risultati essere sovra-regolati mentre 2.135 sotto-regolati. Inoltre i geni sono stati classificati in differenti categorie funzionali mediante Gene Ontology (GO) e sulla base della loro similarità di sequenza a proteine note nel database UniProt annotate con domini InterPro e COG. I risultati ottenuti consentiranno di delucidare i meccanismi molecolari coinvolti nel processo di senescenza fiorale e forniranno una vasta risorsa genomica che faciliterà il miglioramento genetico e sarà indispensabile per ricerche future su questa specie
Benzyladenine and thidiazuron postharvest treatments for preserving cut lily flowers
No full textThe vase life of cut lilies stored for a long time or transported over long
distances, may be reduced. Typical postharvest problems are early tepal wilting and
abscission and leaf yellowing. Following harvest, chlorophyll losses are induced by
the lack of endogenous cytokinins, which are biosynthesized in roots. As the roots
are removed there is no cytokinin supply to the shoot in the postharvest phase. The
objective of this work was to evaluate thidiazuron as a potential postharvest
treatment for preventing chlorophyll losses during storage and for extending the
vase life. Lily flowers were harvested at commercial stage when buds begin to show
colour. Thidiazuron 10 μM was compared with benzyladenine 50 or 100 μM; both
were applied as pulse or continuous treatments. After storing cut flowers for three
weeks at 5°C, flowers were transferred to a postharvest evaluation room under
controlled environmental conditions. Vase life, chlorophyll content, weight change
and relative water content were monitored. Results showed that thidiazuron-treated
stems had higher chlorophyll content compared with the control and benzyladenine
treatments. After three weeks of cold storage, the chlorophyll content of
thidiazuron-treated flowers was 0.84 mg/g FW which was significantly higher than
the content of the control (0.57 mg/g FW). Thidiazuron slowed down the
degradation processes and, after storage, the chlorophyll decline was only 25% of
the initial value. Weight loss was higher in continuously applied treatments
compared with control and pulse treatments. In conclusion, results obtained showed
that the best treatment for preserving cut lilies was a pulse treatment for 24 h with
10 μM thidiazuron
Effect of Salt Spray on Six Ornamental Species
No full textMarine aerosol strongly affects the growth and development of urban, garden
and landscape plants. The few studies available are focused on the sodium chloride
effect on plant growth, usually applied in the irrigation water or substrate media. No
information is available on responses of plants to marine aerosol. Therefore, the aim
of this work was to evaluate the physiological responses of some species to sea water
nebulisation treatment. Species were selected among those that are commonly used
along the seaside and among those that might be potentially used. Plants were
bought from local nursery and species used were: Acacia cultriformis, Callistemon
citrinus, Carissa edulis microphylla, Gaura lindheimeri, Jasminum sambac, Westringia
fruticosa. Plants were placed in randomised block in greenhouse and treated once a
day for 5-10 seconds with sea water or irrigation water (control) using a nebulisation
system.
The effect of marine aerosol was studied by monitoring leaf chlorophyll a
fluorescence, chlorophyll content, and leaf area damage by image analysis.
Results were different among species. The effect of treatment was represented
by leaf necrosis, reduction of chlorophyll and chlorophyll a fluorescence. The
resistant species was Westringia fruticosa, while the intolerant species were A.
cultriformis and G. lindheimeri. Intermediate behaviour was observed in the other
species
Colours intensity and flower longevity of garden roses
Full text linkInteractions of garden botanical composition with human senses generate sensations and emotions that may give pleasure and welfare to observers. Among the garden plants, roses are the most important for the wide range of varieties and flower colours. This review is focused on physiological factors that regulate flower longevity and colour persistence in roses that are generally used for garden decorations. Genes that encode for pigments biosynthesis can be used for improving flower colours. The colour persistence of flowers is tightly related to senescence. In fact, senescence associated genes have been discovered and the study of their function may be useful for genetic improvement for extending the flowering periods. The flower colour and the length of the flowering periods are very important factors that contribute to the garden beauty. Colours cannot be objectively appreciated because they can be differently appreciated by the observers. Therefore, sensations and emotions that rose alone or in combinations with other shrubs and perennials in a garden cannot be predictable
Spatial temporal gene expression of ethylene biosynthesis enzymes and receptors in Hibiscus rosa-sinensis L. flowers
No full textApplication of Actiwave® for Improving the Rooting of Camellia Cuttings
No full textBiostimulants are generally able to improve mineral use efficiency, enhance plant tolerance to biotic and abiotic stresses and stimulate some physiological processes related to development. In our studies, Actiwave® was tested in floricultural crops such as Camellia japonica L. to speed up growth reducing the nursery. The experiments were performed on flowering camellia, using non-rooted cuttings treated with Actiwave® (Valagro Spa) and gibberillic acid (GA3). The Actiwave was applied providing 0.015 or 0.03 ml per cutting, while the GA3 was applied 1.25 or 2.5 mg per cutting. Treatments were repeated each month with eight applications in total. The biostimulant was distributed on the substrate with a volume of 100 ml. The GA3 instead was nebulized on the leaves and on the substrate of each cutting. Rooting was monitored during the whole experimental period. The measurements of fresh and dry weight were taken after 127 days. Results showed that both Actiwave® and GA3 stimulated the rooting compared with control. The two concentrations of Actiwave® had the same effect, with an average fresh root mass of 0.5 g. The treatment with GA3 was observed for a dose-effect response. The differences in dry weight were observed only on roots, and values were significantly higher in the treatments compared to the control
Effect of washing treatments on chlorophyll a fluorescence and vitamin C content in minimally processed lamb’s lettuce during storage
No full textFresh-cut vegetables represent a good source of vitamin C. Lamb’s lettuce is a very rich source of this vitamin and its cultivation is constantly growing. Sanitary quality is a key aspect of fresh-cut products. Among the washing and sanitizing treatments good results has been obtained by using organic acids such as citric and ascorbic. The effect of citric or ascorbic acids as washing treatments was evaluated in lamb’s lettuce (Valerianella olitoria L.) during cold storage on the endogenous vitamin C content and chlorophyll a fluorescence. Leaves treated with citric acid had the highest content in vitamin C during the first 5 days of storage. Results from the fluorescence of chlorophyll a indicate that the samples treated with citric acid were less stressed compared to the other ones. For this reason citric acid can be successfully used in the fresh-cut washing to maintain the nutritional quality of lamb’s lettuce
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
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