1,720,995 research outputs found
Effect of Different Priming Treatments on Quality of Long-Term Stored Seeds of Apium graveolens var. rapaceum DC
No full textIn order to improve germplasm preservation of local cultivar “Friulano”, belonging to Apium graveolens var. rapaceum
(Miller) Gaudin) seed germination of a seed lot, stored for prolonged time at -20°C, was assessed in comparison to that
of a commercial cultivar. In order to increase the seed performance during germination, three different priming pretreatments
(hydropriming for 24 h, osmopriming for 24 h, and osmopriming for 7 days) were performed. Additionally,
seed sowing was undertaken on both potting soil and Petri dish plate condition. Analysis of seed quality was estimated
by measurement of germination percentage, germination energy and the time to reach the 50% of full germination (T50).
The results evidenced that conservation of celeriac dried seeds of “Friulano” cultivar at -20°C for one year maintained a
good level of seed germination (ranging from 38% to 53%), not statistically diverse from the that of commercial cultivar,
for both short hydro- and osmopriming treatments. The germination percentage increased when primed seeds have
been treated in Petri dishes (up to 70%-80%). Furthermore, osmopriming for 24 h positively affected the germination
energy, similarly to that observed in commercial cultivar, being statistically higher compared to hydropriming- and
prolonged osmopriming-treated samples. Accordingly, T50 in short osmopriming treated seeds was low, indicating
that this treatment induced a rapid and uniform germination, being most of the seeds germinated within one week.
In conclusion, these findings represent an important informative step in amelioration of ex situ conservation of a rare
autochthonous horticultural cultivar in North-eastern of Italy
Correction to: Fodder value and physiological aspects of rainfed smooth vetch affected by biofertilizers and supplementary irrigation in an agri-silviculture system (Agroforestry Systems, (2021), 10.1007/s10457-021-00695-7)
No full textIn the original publication of the article, Table 3 was incorrectly published. This has been corrected with this Correction. The original article has been corrected
Fodder value and physiological aspects of rainfed smooth vetch affected by biofertilizers and supplementary irrigation in an agri-silviculture system
No full textIn an agri-silviculture of the plum (Prunus domestica L. Cv. Opal), the forage quality of smooth vetch (Vicia dasycarpa L.) was evaluated. For this purpose, a two-year (2016 and 2017) factorial experiment was conducted based on randomized complete block design with three replications at Urmia University, Iran. The treatments included the combined and individual application of biofertilizers {Azotobacter chroococcum (Az), Thiobacillus spp. (Th)., Rhizophagus intraradices (AMF) and control} under rainfed and once supplementary irrigation. The results showed that irrigated plants contained higher P than rainfed plants. Dual inoculation with “AMF + Az” had higher Ash, K, CP and WSC than plants with fungal or bacterial inoculation alone. In comparison with control, biofertilizers improved the forage and protein yield by 32 and 45.50% under rainfed conditions and by 47 and 60.04% under supplementary irrigation, respectively. The amount of CAT, GR, APX, and SOD were reduced in rainfed plants, but the co-inoculation of mycorrhizal plants with Az and/or Th enhanced enzymatic antioxidants. In conclusion, the combined use of AMF and Az improved smooth vetch forage quantity and quality in irrigated plants as much as rainfed did, and hence it can be desirable for sustainable agriculture
'Last In-First Out': Seasonal variations of non-structural carbohydrates, glucose-6-phospate and ATP in tubers of two Arum species
No full textKnowledge on the metabolism of polysaccharide reserves in wild species is still scarce. In natural sites we collected tubers of Arum italicum Mill. and A. maculatum L. - two geophytes with different apparent phenological timing, ecology and chorology - during five stages of the annual cycle in order to understand patterns of reserve accumulation and degradation. Both the entire tuber and its proximal and distal to shoot portion were utilised. Pools of non-structural carbohydrates (glucose, sucrose and starch), glucose-6-phosphate and ATP were analysed as important markers of carbohydrate metabolism. In both species, starch and glucose content of the whole tuber significantly increased from sprouting to the maturation/senescence stages, whereas sucrose showed an opposite trend; ATP and glucose-6-phosphate were almost stable and dropped only at the end of the annual cycle. Considering the two different portions of the tuber, both ATP and glucose-6-phosphate concentrations were higher in proximity to the shoot in all seasonal stages, except the flowering stage. Our findings suggest that seasonal carbon partitioning in the underground organ is driven by phenology and occurs independently of seasonal climate conditions. Moreover, our results show that starch degradation, sustained by elevated ATP and glucose-6-phosphate pools, starts in the peripheral, proximal-to-shoot portion of the tuber, consuming starch accumulated in the previous season, as a 'Last In-First Out' mechanism of carbohydrate storage. © 2017 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands
The Possible Role of Non-Structural Carbohydrates in the Regulation of Tree Hydraulics
Full text linkThe xylemis a complex systemthat includes a network of dead conduits ensuring long-distance
water transport in plants. Under ongoing climate changes, xylem embolism is a major and recurrent
cause of drought-induced tree mortality. Non-structural carbohydrates (NSC) play key roles in plant
responses to drought and frost stress, and several studies putatively suggest their involvement in
the regulation of xylem water transport. However, a clear picture on the roles of NSCs in plant
hydraulics has not been drawn to date. We summarize the current knowledge on the involvement
of NSCs during embolism formation and subsequent hydraulic recovery. Under drought, sugars are
generally accumulated in xylem parenchyma and in xylem sap. At drought-relief, xylem functionality
is putatively restored in an osmotically driven process involving wood parenchyma, xylem sap and
phloem compartments. By analyzing the published data on stem hydraulics and NSC contents under
drought/frost stress and subsequent stress relief, we found that embolism build-up positively correlated
to stem NSC depletion, and that the magnitude of post-stress hydraulic recovery positively correlated
to consumption of soluble sugars. These findings suggest a close relationship between hydraulics and
carbohydrate dynamics. We call for more experiments on hydraulic and NSC dynamics in controlled
and field conditions
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
Variations on the Author
Full text link“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
Full text linkWe 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
Green synthesis of Ag nanoparticles using plant metabolites
Full text linkNano-biotechnology is one of the most promising areas in modern nanoscience and technology. In this emerging area of research, nanoparticles (NPs) play an important role since the large-scale production and huge numbers of utilization. Gold and silver nanoparticles are among the most extensively studied nanomaterials, since they show high stability and low chemical reactivity in comparison to other metals. They are commonly synthesized using toxic chemical reducing agents able to reduce metal ions into uncharged NPs and/or high energy supplied procedures. The most commonly used method for the synthesis of NPs requires toxic chemicals like N,N-dimethyl formamide (DMF) or trisodium citrate, but recently a green technique, based on natural reducing agents, has been suggested to substitute the nature-unfriendly chemical methods. Many scientific works put in evidence the efficacy of plant extracts to reduce metal salts into the respective NPs, but this process lacks a clear control of NPs shapes and dimensions, since many different metabolites present into the extracts could participate to the process. This paper aims to clarify the reducing action of single pure natural compounds usually present in plant tissues and to obtain a stable and reproducible protocol for NPs synthesis
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