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161.
Sergio Pietro Ferrante Sergio Lucretti Silvia Reale Alessandro De Patrizio Loredana Abbate Nicasio Tusa Maria-Teresa Scarano 《Euphytica》2010,173(2):223-233
We report the accurate determination of the allelic configurations of a total of eight new citrus tetraploid hybrids by means
of SSR analysis, coupled with capillary electrophoresis, and PCR based dosage effects. Tetraploid hybrids were spontaneously
obtained from different interploid crosses (2x × 4x) between diploid ‘Femminello’ lemon and the allotetraploid somatic hybrid
(2n = 4x = 36) ‘Key’ lime + ‘Valencia’ orange, and between diploid ‘Wilking’ and ‘Fortune’ mandarins and an autotetraploid ‘Dancy’
mandarin (2n = 4x = 36). To understand the opportunity to employ them in further backcross programs, the cytological mechanisms underlying
their ploidy level were unambiguously determined using six SSR primers. PCR conditions were optimized and skewness in template/product
ratios were verified. Tetraploid allelic configurations were determined from PCR based dosage effects using electropherogram
peak heights to estimate the copy number per allele. In all the tetraploid hybrids we found out that diploginy (2n eggs) has occurred, contributing the extra haploid genome in the tetraploids. According to the marker genotypes, it was further
inferred that the 2n eggs in ‘Femminello’ lemon resulted from first division restitution (FDR), while in ‘Wilking’ and ‘Fortune’ mandarins 2n eggs occurred in second division restitution (SDR). These new genotypes, with their improved genetic female background, can
be therefore considered very valuable in our citrus genetic improvement program as pollen donors in backcrosses suitable to
eliminate negative traits. 相似文献
162.
Spaccini R Baiano S Gigliotti G Piccolo A 《Journal of agricultural and food chemistry》2008,56(3):1017-1024
A sequential chemical fractionation was applied to a compost, with its dissolved organic matter (DOM) extracted in water and separated in hydrophilic (HiDOM) and hydrophobic (HoDOM) components and a water extract, following oxidation of compost suspension with an oxygen flux (TEA). The components sequentially isolated by mild extractions and hydrolyses as structurally unbound (SU), weakly bound (WB), and strongly bound (SB) to the matrix of the bulk compost and its water-soluble fractions were identified in their molecular structure. The bulk compost was rich with components derived from both aromatic (phenolic compounds) and aliphatic (long-chain fatty acids, hydroxy acids, diacids, and alcohols) structures of suberins, whereas components derived from cutins were especially extracted from TEA, HoDOM, and HiDOM. The TEA sample also yielded a significant amount of oxidized products that was dominated by dehydroabietic acids. The fractionation sequence highlighted the different intermolecular interactions that bound the isolated molecular components to the compost complex matrix. While a significant part of the bulk compost was still present as a solid residue at the end of the sequential fractionation, all water-soluble fractions were almost completely hydrolyzed. These results indicate that the water-soluble components of compost may be readily separated from the compost matrix and contribute to the environmental dynamics of natural organic matter. 相似文献
163.
Research and development of an innovative production system for hemp (Cannabis sativa L.) fibre for textile use requires the integration of multidisciplinary knowledge from cultivation technique to realization of end products. Research was carried out to study the effect of the agronomic factors cultivation year (2003–2004), genotype (Futura 75 and Tiborszallasi), plant population (120, 240 and 360 plants m−2) and harvesting time (beginning and full flowering) on fibre yield and quality in the whole hemp stem, and in the basal and apical stem portions separately. The study of separate stem portions was done to determine the effect on fibre quality of an innovative harvesting and processing system in which hemp stems are cut in two portions of approximately 1 m at harvest to enable processing on modern flax scutching lines. 相似文献
164.
Violeta da Rocha Perini Alessandro Loureiro Paschoalini Cláudia Kelly Fernandes da Cruz Rita de Cássia Gimenes Alcântara de Rocha José Augusto Senhorini Dirceu Marzulo Ribeiro Paulo Sérgio Formagio Nilo Bazzoli Elizete Rizzo 《Fish physiology and biochemistry》2013,39(6):1473-1484
This study investigated for the first time the reproductive biology of Prochilodus lineatus in a system of rivers in southeastern Brasil, relating it to the role of tributary rivers in the reproductive success of this important commercial fish in the Upper Paraná River basin, where a cascade of hydroelectric dams were deployed. Specimens were caught bimonthly in three river sites: (S1) Grande River, downstream from the Porto Colômbia dam; (S2) Pardo River; and (S3) Mogi Guaçu River. Sex steroid plasma levels, fecundity, follicular atresia, oocyte diameter and gonadosomatic index (GSI) were compared among sites. In S1, fish exhibited changes in the reproductive parameters: lower GSI, oocyte diameter and fecundity and higher follicular atresia index, when compared to S2 and S3. Frequency of maturing fish was higher in S3 and spawning was only registered in S3. In sites S2 and S3, plasma concentrations of testosterone and 17β-estradiol in females and testosterone in males showed wide variations following gonadal maturation. Fish from S1 showed few significant variations in sex steroid concentrations throughout the gonadal cycle. These results indicate that P. lineatus does not reproduce in Grande River (S1), but probably uses the Pardo River (S2) as a migratory route towards the Mogi Guaçu River (S3) where they complete gonadal maturation and spawning. Our findings contribute for understanding the reproductive biology of P. lineatus and to highlight the importance of tributaries in impounded rivers as a favourable environment for migration and spawning of fish. 相似文献
165.
166.
Pellegrini Marco Abbiati Marco Bianchini Augusto Colangelo Marina Antonia Guzzini Alessandro Mikac Barbara Ponti Massimo Preda Giovanni Saccani Cesare Willemsen Albert 《Journal of Soils and Sediments》2020,20(6):2685-2696
Journal of Soils and Sediments - The paper aims to show the preliminary monitoring and field test results of the innovative technology tested in the framework of the MARINAPLAN PLUS LIFE project... 相似文献
167.
Steven W Purcell Annie Mercier Chantal Conand Jean‐François Hamel M Verónica Toral‐Granda Alessandro Lovatelli Sven Uthicke 《Fish and Fisheries》2013,14(1):34-59
Worldwide, most sea cucumber fisheries are ineffectively managed, leading to declining stocks and potentially eroding the resilience of fisheries. We analyse trends in catches, fishery status, fishing participation and regulatory measures among 77 sea cucumber fisheries through data from recent fishery reports and fishery managers. Critical gaps in fisheries biology knowledge of even commonly targeted species undermine the expected success of management strategies. Most tropical fisheries are small‐scale, older and typified by numerous (>8) species, whereas temperate fisheries are often emerging, mono‐specific and industrialized. Fisher participation data indicated about 3 million sea cucumber fishers worldwide. Fisher participation rates were significantly related to the average annual yield. permanova analysis showed that over‐exploited and depleted fisheries employed different sets of measures than fisheries with healthier stocks, and a non‐metric multidimensional scaling ordination illustrated that a broad set of regulatory measures typified sustainable fisheries. SIMPER and regression tree analyses identified that the dissimilarity was most related to enforcement capacity, number of species harvested, fleet (vessel) controls, limited entry controls and rotational closures. The national Human Development Index was significantly lower in countries with over‐exploited and depleted fisheries. Where possible, managers should limit the number of fishers and vessel size and establish short lists of permissible commercial species in multispecies fisheries. Our findings emphasize an imperative to support the enforcement capacity in low‐income countries, in which risk of biodiversity loss is exceptionally high. Solutions for greater resilience of sea cucumber stocks must be embedded within those for poverty reduction and alternative livelihood options. 相似文献
168.
Alessandro Bonanno 《Agriculture and Human Values》1989,6(1-2):2-10
This paper provides an analytical panorama of agriculture in the European context to be employed as a background for reading the articles contained in this issue of Agriculture and Human Values. Brief summaries of their contents constitute the concluding part of the present contribution. 相似文献
169.
Objective— To report sartorius muscle contracture in a dog.
Study Design— Case report.
Animals— A 5-year-old, male, German Shepherd dog.
Methods— After a 2-month history of right hindlimb lameness was treated by tenectomy of the caudal sartorius muscle for sartorius muscle contracture.
Results— One month after surgery there was complete remission of clinical signs; however, after 12 months, there was partial reunion of sartorius caudal belly and onset of gracilis muscle contracture.
Conclusions— Contracture of the sartorius muscle in dogs is seemingly rare and similar to gracilis muscle contracture with which it may be confused. Differentiation requires knowledge of muscular anatomy, careful palpation, and surgical inspection.
Clinical Relevance— Sartorius muscle contracture can be treated by tenectomy or removal of contracted muscle tissue, however, long-term outcome suggests the need to develop approaches that prevent recurrence caused by scarring of transected tissues. 相似文献
Study Design— Case report.
Animals— A 5-year-old, male, German Shepherd dog.
Methods— After a 2-month history of right hindlimb lameness was treated by tenectomy of the caudal sartorius muscle for sartorius muscle contracture.
Results— One month after surgery there was complete remission of clinical signs; however, after 12 months, there was partial reunion of sartorius caudal belly and onset of gracilis muscle contracture.
Conclusions— Contracture of the sartorius muscle in dogs is seemingly rare and similar to gracilis muscle contracture with which it may be confused. Differentiation requires knowledge of muscular anatomy, careful palpation, and surgical inspection.
Clinical Relevance— Sartorius muscle contracture can be treated by tenectomy or removal of contracted muscle tissue, however, long-term outcome suggests the need to develop approaches that prevent recurrence caused by scarring of transected tissues. 相似文献
170.
Willem Verhagen Astrid J. A. Van Teeffelen Andrea Baggio Compagnucci Laura Poggio Alessandro Gimona Peter H. Verburg 《Landscape Ecology》2016,31(7):1457-1479