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401.
402.
Beak microstructure analysis as a tool to identify potential rearing stress for Octopus vulgaris paralarvae
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Rita Melo Franco‐Santos Catalina Perales‐Raya Eduardo Almansa Marleen De Troch Diego Garrido 《Aquaculture Research》2016,47(9):3001-3015
Octopus vulgaris is a viable candidate for commercial aquaculture, but rearing procedures might stress individuals and result in diminished growth and survival. This study investigated the relationship between possible stress sources (tank transposition and syphoning) when rearing O. vulgaris paralarvae and the deposition pattern of growth increments in their beak microstructure. Light intensity at the facility was heterogeneous, and accounted for with an experimental design consisting of blocks without replicates. Growth and survival were estimated and possible effects of handling were tested for both parameters. Increments and stress marks were counted in 120 paralarval upper jaws (UJ), and the number of UJs with a mark on the day of stress application (day 8) was quantified. Differences in light intensity, diet quantity and total number of marks in the UJ were also compared between treatments. Growth and survival were statistically similar between treatments, although the control treatment showed a tendency for higher survival rates. Age at first increment deposition coincided with day 1 of experiment, and a 1 increment day?1 deposition rate was validated for the experiment duration. The number of stress marks was significantly different between the control and other treatments, indicating that handling might cause stress and that marks can be used as a biomarker for stress, although the occurrence of stress marks on day 8 was not significantly different. Light intensity and diet might have also been relevant stressors and confounded the results. The results herein presented are important for improving rearing conditions for O. vulgaris paralarvae. 相似文献
403.
Angjelina Belaj Concepcion Muñoz-Diez Luciana Baldoni Zlatko Satovic Diego Barranco 《Scientia Horticulturae》2010
Genetic diversity and relationships between local cultivars and wild olive trees from three important Spanish olive-growing regions, Andalusia (South), Catalonia and Valencia (from Eastern Mediterranean Coastal area), were studied by means of eight SSR loci. Distinct allelic composition and heterozygosity levels were found in wild olive populations and cultivars. The observed patterns of genetic variation revealed: a) the independent clustering of Andalusian wild olives in a separate gene pool, b) the belonging of wild populations and most cultivars from Catalonia to another gene pool, c) the joined clustering of Andalusian and a set of Valencian cultivars in a third gene pool, and d) clustering of wild individuals from Valencia to the three different gene pools. These results suggest that wild populations of Andalusia may represent true oleasters, the ones from Catalonia may be feral forms derived from cultivar seed spreading, while the population of Valencia seems to be the most admixed one. The significant differentiation between Andalusian and most Catalonian cultivars is indicating an independent selection of olive cultivars in the two regions. The detection of a certain wild genetic background in some Catalonian and Valencian cultivars and the similarity found between wild and cultivated forms may suggest the use of local wild trees in olive domestication. The proposed scenario for the development of olive cultivars in Andalusia includes an empirical selection of outstanding local wild genotypes followed by various generations of crosses and various replanting campaigns, as well as possible introductions of ancestral cultivars. Therefore, our findings would lead us to support the hypothesis that the current diversity found in Spanish olive cultivars may be regionally differentiated and due to both, autochthonous and allochthonous origin. The information obtained in this work gives insights into the genetic resources of the main olive producing country, demonstrating that wild olive populations and local cultivars both represent potential sources of useful variability for olive breeding programs. 相似文献
404.
Broomrape management in faba bean 总被引:1,自引:0,他引:1
Alejandro Pérez-de-Luque Hanan Eizenberg Jan H. Grenz Josefina C. Sillero Carmen Ávila Joachim Sauerborn Diego Rubiales 《Field Crops Research》2010
Broomrapes (Orobanche spp. and Phelipanche spp.) are weedy root parasites that represent a major constraint for faba bean (Vicia faba) cultivation in the Mediterranean area. Control methods are being developed that comprise techniques ranging from agronomical practices to precision farming, including chemical and biological control, genetic and induced resistance, modelling, and probably nanotechnology in a nearby future. However, the main concern is that to date, no single method of control provides complete protection against these parasites. For that reason, an integrated approach is needed in which a variety of such techniques are combined, in order to maintain parasite populations below threshold levels of damage. 相似文献
405.
406.
Alarcón Marcelo Bustos Michelle Mendez Diego Fuentes Eduardo Palomo Ivan Lutz Mariane 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(2):215-222
Plant Foods for Human Nutrition - Cardiovascular disease (CVD) is the leading cause of death throughout the world. A major risk factor for CVD is platelet aggregation. Various plant extracts... 相似文献
407.
Truchado P Tourn E Gallez LM Moreno DA Ferreres F Tomás-Barberán FA 《Journal of agricultural and food chemistry》2010,58(24):12678-12685
To select and establish floral biomarkers of the botanical origin of Diplotaxis tenuifolia honeys, the flavonoids and glucosinolates present in bee-deposited nectar collected from hive combs (unripe honey) and mature honey from the same hives fron which the unripe honey samples were collected were analyzed by LC-UV-PAD-ESI-MS(n). Glycosidic conjugates of the flavonols quercetin, kaempferol, and isorhamnetin were detected and characterized in unripe honey. D. tenuifolia mature honeys contained the aglycones kaempferol, quercetin, and isorhamnetin. The differences between the phenolic profiles of mature honey and freshly deposited honey could be due to hydrolytic enzymatic activities. Aliphatic and indole glucososinolates were analyzed in unripe and mature honeys, this being the first report of the detection and characterization of glucosinolates as honey constituents. Moreover, these honey samples contained different amounts of propolis-derived flavonoid aglycones (1765-3171 μg/100 g) and hydroxycinnamic acid derivatives (29-1514 μg/100 g). Propolis flavonoids were already present in the freshly deposited nectar, showing that the incorporation of these compounds to honey occurs at the early steps of honey production. The flavonoids quercetin, kaempferol, and isorhamnetin and the glucosinolates detected in the samples could be used as complementary biomarkers for the determination of the floral origin of Argentinean Diplotaxis honeys. 相似文献
408.
Diego Pereira Santos Mauriana da Rocha Sobrinho Maria de Fátima de Castro Oliveira Niedja Bezerra Costa Tiago Massi Ferraz Fabrício de Oliveira Reis Heder Braum Eliemar Campostrini Fábio Afonso Mazzei Moura de Assis Figueiredo 《林业研究》2021,42(6):2473-2484
In scenarios of climatic change when increased global temperatures can be expected,it is essential to search for technologies that favor sapling survival and gr... 相似文献
409.
Diego Tassinari Maria luiza de Carvalho Andrade Moacir de Souza Dias Junior Ricardo Previdente Martins Wellington Willian Rocha Paula Sant Anna Moreira Pais Zlio Resende de Souza 《Soil Use and Management》2019,35(3):400-411
Eucalyptus forests play a major role in the world economy, providing raw materials for different purposes. In planted forests, harvest operations performed by heavy machinery may cause severe soil compaction. This study aimed to evaluate the impact of a full‐tree harvesting system in planted eucalyptus forests from Northeastern Brazil. Different soils were evaluated (two Hapludults and one Haplorthod) in two horizons (BA and Bt). We tested different equipment, namely feller buncher, skidder (with traffic intensities of 3, 6, 12 and 16 passes), flail (at different ground‐contact points), grapple saw and loader. The soil physical attributes reflected not only the impact of equipment traffic but also the intrinsic differences between the soils. Bulk density (ranging from 1.36 to 1.80 t m?3 after trafficking) related well to soil class and horizon. Precompression stress (ranging from 203 to 430 kPa) and degree of compaction (76%–94%) following trafficking were well correlated, while increase in bulk density (reaching a maximum of 20%) related more strongly to soil moisture. A contingency table was constructed with the number of compacted samples and further examined by correspondence analysis. Compaction varied according to soil, horizon and equipment, indicating that machine–soil interactions are very specific and demand detailed research under different conditions. The Haplorthod experienced the greatest amount of compaction, whereas the Hapludult‐2 was more resistant (60% and 25% of compacted samples, respectively). The grapple saw and the skidder at higher traffic intensities (12 and 16 passes) exerted the highest mechanical impacts (81% and 67% of compacted samples, respectively). 相似文献
410.
Rajakumar R San Mauro D Dijkstra MB Huang MH Wheeler DE Hiou-Tim F Khila A Cournoyea M Abouheif E 《Science (New York, N.Y.)》2012,335(6064):79-82
Complex worker caste systems have contributed to the evolutionary success of advanced ant societies; however, little is known about the developmental processes underlying their origin and evolution. We combined hormonal manipulation, gene expression, and phylogenetic analyses with field observations to understand how novel worker subcastes evolve. We uncovered an ancestral developmental potential to produce a "supersoldier" subcaste that has been actualized at least two times independently in the hyperdiverse ant genus Pheidole. This potential has been retained and can be environmentally induced throughout the genus. Therefore, the retention and induction of this potential have facilitated the parallel evolution of supersoldiers through a process known as genetic accommodation. The recurrent induction of ancestral developmental potential may facilitate the adaptive and parallel evolution of phenotypes. 相似文献