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331.
Shravani Basu Sean Mayes Michael Davey Jeremy A. Roberts Sayed N. Azam-Ali Richard Mithen Remy S. Pasquet 《Euphytica》2007,157(1-2):59-68
Controlled crosses in bambara groundnut were attempted between a range of thirty-six bambara groundnut landraces (thirty domesticated
(V. subterranea var. subterranea) and six wild (V. subterranea var. spontanea)). Ten F1 seed were produced. Of these, eight germinated producing F2 populations. On seed set, four populations could be unambiguously confirmed as true crosses by F3 seed coat colour. A single F2 population, derived from a domesticated landrace from Botswana (DipC; female parent) crossed with a wild accession collected
in Cameroon (VSSP11; male parent) was used to study a range of agronomic and domestication traits. These included; days to
emergence, days to flowering, internode (fourth) length at harvest, number of stems per plant, leaf area, Specific Leaf Area
(SLA), Carbon Isotope Discrimination (CID), 100 seed weight, testa colour and eye pattern around the hilum. On the basis of variation for internode length and stems
per plant, 14 small F3 families were selected and grown under field conditions to further investigate the genetic basis of the ‘spreading’ versus
‘bunched’ plant character, a major difference between wild and cultivated bambara groundnut. Results presented suggest that
traits including leaf area, SLA, CID and 100 seed weight are controlled by several genes. In contrast, the variation for traits
such as internode length, stems per plant, days to emergence and seed eye pattern around the hilum are likely to be under
largely monogenic control. The results of this work are discussed in relation to the domestication of bambara groundnut. 相似文献
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In the temperate forests of the southern Andes, southern beech species (Nothofagus), the dominant tree species of the region, experience severe defoliation caused by caterpillars of the Ormiscodes genus (Lepidoptera: Saturniidae). Despite the recent increase in defoliation frequency in some areas, there is no quantitative
information on the spatial extent and dynamics of these outbreaks. This study examines the spatial patterns of O. amphimone outbreaks in relation to landscape heterogeneity. We mapped defoliation events caused by O. amphimone in northern (ca. 40–41°S) and southern Patagonian (ca. 49°S) Nothofagus forests from Landsat imagery and analyzed their spatial associations with vegetation cover type, topography (elevation, slope
angle, aspect) and mean annual precipitation using overlay analyses. We used these data and relationships to develop a logistic
regression model in order to generate maps of predicted susceptibility to defoliation by O. amphimone for each study area. Forests of N. pumilio are typically more susceptible to O. amphimone outbreaks than lower elevation forests of other Nothofagus species (N. dombeyi and N. antarctica). Stands located at intermediate elevations and on gentle slopes (<15°) are also more susceptible to defoliation than higher
and lower elevation stands located on high angle slopes. Stands in areas with intermediate to high precipitation, relative
to the distribution of Nothofagus along the precipitation gradient, are more susceptible to O. amphimone attack than are drier areas. Our study represents the first mapping and spatial analysis of insect defoliator outbreaks in
Nothofagus forests in South America. 相似文献
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Ingrid van Hoek Hannah Hodgkiss-Geere Elizabeth F. Bode Julie Hamilton-Elliott Paul Mõtsküla Valentina Palermo Yolanda Martinez Pereira Geoff J. Culshaw Jeremy Laxalde Joanna Dukes-McEwan 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(6):2197-2210
336.
Hidalgo M Oruna-Concha MJ Kolida S Walton GE Kallithraka S Spencer JP de Pascual-Teresa S 《Journal of agricultural and food chemistry》2012,60(15):3882-3890
Consumption of anthocyanins has been related with beneficial health effects. However, bioavailability studies have shown low concentration of anthocyanins in plasma and urine. In this study, we have investigated the bacterial-dependent metabolism of malvidin-3-glucoside, gallic acid and a mixture of anthocyanins using a pH-controlled, stirred, batch-culture fermentation system reflective of the distal human large intestine conditions. Most anthocyanins have disappeared after 5 h incubation while gallic acid remained constant through the first 5 h and was almost completely degraded following 24 h of fermentation. Incubation of malvidin-3-glucoside with fecal bacteria mainly resulted in the formation of syringic acid, while the mixture of anthocyanins resulted in formation of gallic, syringic and p-coumaric acids. All the anthocyanins tested enhanced significantly the growth of Bifidobacterium spp. and Lactobacillus-Enterococcus spp. These results suggest that anthocyanins and their metabolites may exert a positive modulation of the intestinal bacterial population. 相似文献
337.
Added (glucose addition) versus accumulated (in situ sugar development via cold-temperature storage) sugar treatments were investigated in relation to acrylamide formation within fried potato strips at standardized levels of finish-fried color (Agtron color scores ranged from 36 to 84). The added sugar treatment exhibited a relatively reduced rate of acrylamide formation and generally possessed a lower and less variable acrylamide content (61-1290 ng/g) than the accumulated sugar scheme (61-2191 ng/g). In a subsequent experiment, added fructose applied to strip surfaces via dipping prior to frying favored acrylamide formation over color development relative to added glucose, for which the reverse trend was observed. Thus, where acrylamide differences were noted between added and accumulated sugar treatments (given equivalent Agtron color scores), this result was likely aided by the relative higher fructose content in strips of the accumulated sugar scheme rather than simply a greater relative concentration of total reducing sugars. 相似文献
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Penelope Perkins-Veazie Jeremy Pattison Gina Fernandez Guoying Ma 《International Journal of Fruit Science》2016,16(4):220-227
ABSTRACTThe advanced selections, NCS 10-038 and NCS 10-156, from the North Carolina breeding program were compared to the traditionally used cultivars, Camarosa and Chandler, for storage life and fruit composition in 2014 and 2015. Postharvest quality of NCS 10-038 was similar to that of ‘Camarosa’ and ‘Chandler’ after 8 days storage at 4 °C. NCS 10-156 was significantly worse in overall appearance and had more fruit shrivel, calyx browning, and mold than the other genotypes. However, NCS 10-156 was highest in soluble solids content and was similar in total anthocyanin content and total phenolic content to ‘Camarosa’ and ‘Chandler’. Further analysis of flavonoids by high performance liquid chromatography showed that NCS 10-156 was much lower in total flavonols than the other genotypes and comparable in anthocyanin pigments to ‘Chandler’. NCS 10-038, while similar in pigment profile to ‘Camarosa’, had less total anthocyanin than the other genotypes. NCS 10-038 had a lighter red color than the other genotypes and was similar in postharvest quality to ‘Chandler’ and ‘Camarosa’ and may be suitable for long-distance markets. NCS 10-156 is slightly softer than the other genotypes and more prone to mold while the higher soluble solids content may make it suitable for direct market sales. Both selections show postharvest promise for strawberry production in the humid mid-South region. 相似文献