1,720,965 research outputs found
Somatic embryogenesis through in vitro anther culture of Citrus sinensis L. Osbeck ‘Moro’
No full textIn many crops, anther culture is the most used method to induce gametic embryogenesis, aimed to regenerate homozygous plants. However, also somatic embryogenesis can be obtained by this method, when somatic tissue is involved in regeneration process. Many factors can affect this procedure, such as genotype, pre-treatments applied to floral buds, pollen developmental stage, donor plant states, culture media composition and growth culture conditions.
Anthers of Citrus sinensis L. Osbeck, cv. Moro, were collected at the vacuolate stage, and after a chilling (4°C) pre-treatment of 7 days, were placed on the same medium, evaluating different temperature stresses applied after the placing in culture.
In this study, the effect of three thermal treatments, compared with direct in vitro culture of the anthers (after the pre-treatment to the floral buds at 4 °C for 7 days), was observed in a Citrus genotype. Regeneration of embryos has been obtained and their characterization, through ploidy analysis and molecular analysis, showed that they were heterozygous tetraploids
Planting Date and Different N-Fertilization Rates Differently Modulate Agronomic and Economic Traits of a Sicilian Onion Landrace and of a Commercial Variety
Full text linkThe onion is one of the most widespread bulb vegetables worldwide. Onion cultivation is common in Sicily, as is the use of local genotypes. Cultivation practices are of particular interest in optimizing yield, quality, and profits. The aim of this study was to assess the agronomic response of a Sicilian landrace (Bianca Calda di Comiso, coded L1) and a commercial variety (Bianca di Maggio, coded V1) to different planting dates and N fertilization rates. An economic appraisal was also performed. The two genotypes were assessed using an experimental split-split-plot design with four levels of nitrogen rates (0, 80, 160, and 220 kg N ha−1) and two different planting dates (8 October 2005 to 9 October 2006 for the early planting date, and 27 December 2005 to 30 December 2006 for the traditional planting date). The marketable yield and production parameters were significantly influenced by the nitrogen dose: higher doses led to a higher total yield, with yield peaks above 60 t ha−1 and the marketable yield ranging from 23% to 54%. Simultaneously, decreases in the firmness (from 7% to 19%) and scale content (from 1% to 3%) were also reported. The L1 landrace showed a higher production than the V1 variety. The crop year did not significantly affect the results, and the traditional planting date appeared to be the most suitable choice in obtaining the best agronomic response. Economic analysis showed that the L1 landrace, with high-N application treatments, produced greater net benefits and marginal rates of return. Thus, the L1 landrace exposed to the highest dosages of nitrogen (160 or 220 kg ha−1) and transplanted during the traditional planting period is the best choice from agronomic and economic points of view
Hops (Humulus lupulus l.) as a novel multipurpose crop for the mediterranean region of europe: Challenges and opportunities of their cultivation
Full text linkThe common hop (Humulus lupulus L.) is a dioecious perennial climbing plant, mainly known for the use of its female inflorescences (cones or, simply, "hops") in the brewing industry. However, the very first interest towards hops was due to its medicinal properties. Actually, the variety of compounds present in almost all plant parts were (and still are) used to treat or prevent several ailments and metabolic disorders, from insomnia to menopausal symptoms as well as obesity and even cancer. Although hops are predominantly grown for hopping beer, the increasing interest in natural medicine is widening new interesting perspectives for this crop. Moreover, the recent success of the craft beer sector all over the world, made the cultivated hop come out from its traditional growing areas. Particularly, in Europe this resulted in a movement towards southern countries such as Italy, which added itself to the already existing hop industry in Portugal and Spain. In these relatively new environments, a complete knowledge and expertise of hop growing practices is lacking. Overall, while many studies were conducted globally on phytochemistry, bioactivity, and the genetics of hops, results from public research activity on basic hop agronomy are very few and discontinuous as well. The objective of this article is to provide an overview of possible uses, phenology, and agronomic aspects of hops, with specific reference to the difficulties and opportunities this crop is experiencing in the new growing areas, under both conventional and organic farming. The present review aims to fill a void still existing for this topic in the literature and to give directions for farmers that want to face the cultivation of such a challenging crop
Establishment of a commercial organic hopyard in a Mediterranean environment: Production attributes and their relationship with soil texture
No full textThe cultivated hops are recently moving towards new growing areas in Southern Europe, boosted by the increasing number of craft breweries and by the higher vulnerability to climate change observed, for this crop, in the traditional growing regions. Despite this clear market and geographic trend, there is a lack of knowledge about pedoclimatic needs and agronomic performances of hops grown in the Mediterranean environment. Particularly, the agronomic potential of a new hopyard during its establishment period is poorly studied even in traditional growing zones. Moreover, a restricted number of plants were usually sampled to gather the few data available, thus leading to a probable overestimation of yield performance. A commercial organic hopyard in central Italy was established and a 2-year (2018-2019) field experiment was set-up to accurately investigate the cone and shoot yield potential of cultivar 'Cascade' and to understand how such yields are related to each other and to soil texture. Hop plants were two-years old when the experiment started; plant population was 4,000 plants ha -1. Forty points within the hopyard were sampled for soil analysis and yield traits. Data were analyzed accounting for spatial dependence of the sampling points. Results show a negative relation between clay content in the soil and hop yields, even though it was significant only in the exceptional rainy season of 2018. Shoot and cone yield were positively and strongly related, suggesting the green shoot yield in spring as a good predictor of hop production. Both shoot and cone yield significantly increased from the second to the third year (+11% and +16%, respectively); however, the unseasonably high rainfall of 2018 probably lowered the yield of the first experimental year. Cone yield attained over this 2-year study (1.24 t ha- 1 and 1.44 t ha- 1 for 2018 and 2019, respectively) was within the published ranges for mature plants. Similarly to cone production, shoot dry matter yield was lower in 2018 (197 kg ha-1) than in 2019 (218 kg ha-1). This study provides the first reliable in-formation on both cone and shoot yield potential of a young organic hopyard under Mediterranean climatic 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
Physiological Stress Indices: A Valuable Tool to Mitigate the Impacts of High Temperatures and Drought on Durum Wheat Yield and Quality
Full text linkDurum wheat (Triticum turgidum L. var. durum Desf.) is one of the world's most important and widely grown cereals, playing a fundamental role in global food security. In countries where it is traditionally cultivated, abiotic stress caused by high temperatures and limited precipitation, exacerbated by the ongoing climate crisis, is the main cause of production losses quality deterioration, and uncertainty in meeting market demand. The objective of this study was to monitor, across five experimental sites, the effect of climatic variability on phenological, morpho-physiological, and agronomic parameters, using physiological stress indices such as RWC, NDVI, and SPAD. The research was conducted during the 2023/2024 season across the southern Italian landscape of Sicily, a region representative of the durum wheat cultivation scenario in hot-arid environments, and one of the main production areas. Analysis of variance (ANOVA) revealed significant differences in most parameters, with the exceptions of the number of spikelets per spike, harvest index, and test weight. In general, a decline in yield and quality was observed across all the sites, with notable variability. High temperatures and the absence of precipitation shortened the elongation-flowering and flowering-maturation stages, influencing the accumulation of growing degree days (GDD) in the more inland sites. In most environments, plants showed reduced growth (average culm height: 41.5 cm), while yields ranged from 10.0 to 27.0 q ha(-)(1). Quality parameters, such as yellow pigment (22.9%-24.3%), protein content (13.6%-15.8%), and gluten content (8.8%-11.9%), were variable depending on environmental conditions. Finally, Pearson's correlation analysis showed strong positive correlations between physiological parameters (SPAD, RWC, NDVI) and yield (r >= 0.8), between the yellow index and yield (r > 0.8), and strong negative correlations between proteins, dry gluten, and yield (r < -0.8). Although durum wheat is drought-tolerant, it is affected by water and thermal stress, which causes spatial and temporal variability in production. Monitoring cereal systems and adopting appropriate techniques could mitigate this vulnerability, supporting cereal farming businesses
Environmental sustainability of cotton: a systematic literature review of life cycle assessments
Full text linkCotton is the world’s most used natural fiber, representing over 80% of global natural fiber use. However, its
cultivation involves considerable consumption of water, energy, fertilizers, and pesticides, which impact both the
environment and human health. Additional impacts arise from consumer activities such as washing and ironing.
This review analyzes twenty peer-reviewed studies on cotton life cycle assessments, selected from Scopus and
Web of Science according to PRISMA guidelines and covering the period 2010–2022. Among the inclusion
criteria, studies addressing the cultivation phase were considered, while the exclusion criteria involved conference papers, book chapters and partial life cycle assessments. These studies indicate that cotton production—from cultivation to the final product—has the greatest impact on water use, energy consumption,
greenhouse gas emissions and toxicity. Organic cotton farming demonstrates lower environmental impacts per
unit area compared to conventional farming, but it exhibits higher impacts when evaluated on a mass basis. This
discrepancy arises from the typically lower yields of organic systems relative to their conventional counterparts,
emphasizing how the choice of functional unit can significantly influence the results and the conclusions drawn.
Industrial processes like dyeing and spinning generate substantial carbon emissions, while consumer
use—particularly washing and drying—accounts for over 65% of total energy consumption. The review identifies
key sustainability issues in cotton production—high demand for and use of water, energy, and chemicals— and
suggests strategies to mitigate the impacts across its life cycle such as efficient irrigation, optimized fertilization,
the adoption of organic or Bt cotton, a shift towards renewable energy sources, and recycling
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
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