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81.
This article builds on the food sovereignty literature to ask pointed questions about the interplay of market forces and political liberalism. Specifically, we use cuisine as a lens to interrogate the assumption that multiculturalism is compatible with Indigenous food sovereignty. Because multicultural inclusion is the means by which Indigenous Peoples’ gastronomies are commodified and alienated, they experience not gastronomic multiculturalism but culinary colonialism. Accordingly, food sovereignty in colonial contexts must embrace both the active sharing and the mindful withholding of food as political acts, and acknowledge that culinary culture is not simply a market commodity but also a politically-embedded process. In drawing together the threads of this argument, we advocate for a broadening of the discussion on Indigenous food sovereignty to include the resistance and resurgence enacted through gastronomy. 相似文献
82.
Sam Oyewole Ajala Amudalat Bolanle Olaniyan Muyideen Oluseyi Olayiwola Anthony Oluwatoyosi Job 《Plant Breeding》2018,137(2):118-126
Low soil nitrogen limits maize (Zea mays L.) production in the West and Central African subregion. Levels of residual genetic variability were determined in two low‐N populations using selfed progeny evaluations, and results obtained indicate large genotypic and phenotypic variances for grain yield under both low‐ and high‐N environments for effective selection, while heritability estimates were generally low. Ear aspect and stay green were the most important traits contributing to grain yield for both populations. Selection reduced days to flowering, ASI and ear aspect, but increased plant height and yield. Yield gains of more than 25% occurred for the two populations under both low and high N with the most significant change of 42% occurring in one population under high N. 相似文献
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86.
Models can play an important role in agricultural planning and management. Thermal time accumulation is a common way of describing phenological development in crop models, but the sensitivity of this concept to water stress is rarely quantified. The effect of pre-anthesis droughts on the timing of anthesis and physiological maturity was assessed for quinoa (Chenopodium quinoa Willd.) var. ‘Santa Maria’, with the help of two field experiments (2005–2006 and 2006–2007) in the central Bolivian Altiplano. Various treatments with different sowing dates and irrigation applications were considered. To evaluate the effect of drought stress on crop development, drought stress during the first 60 days after sowing was assessed with three different stress indicators: the number of days that the soil water content of the root zone was above a threshold, the average relative transpiration, and the sum of daily actual transpiration, standardized for reference evapotranspiration (∑(Ta/ET0)). The best indicator to quantify the effect of pre-anthesis drought stress on phenological development was ∑(Ta/ET0) cumulated until 60 days after sowing. This indicator showed a significant logarithmic relation with the time to anthesis and time to physiological maturity. Correlations of the drought stress indicator with thermal time accumulation were better than with calendar time accumulation. Due to an effect of post-anthesis droughts, the correlations of the drought stress indicator with the time to anthesis were stronger than with the time to physiological maturity. It was also demonstrated that deficit irrigation can contribute to a better agricultural planning due to a better control of the phenological development of quinoa. The proposed relations can be used for modeling phenological development of quinoa in drought prone regions and for efficient deficit irrigation planning. 相似文献
87.
Effects of drought and the presence of the 1BL/1RS translocation on grain vitreosity, hardness and protein content in winter wheat 总被引:1,自引:1,他引:0
Richard M. Weightman Sam Millar Juan Alava M. John Foulkes Lesley Fish John W. Snape 《Journal of Cereal Science》2008,47(3):457-468
Grain texture is an important component of end-use quality in wheat. The effects of water availability on the components of texture; vitreosity, determined using a Light Transflectance meter (LTm), grain hardness measured using the single-kernel characterisation system (SKCS), and protein content, were studied in field experiments of winter wheat in the UK in 2001/2002 and 2002/2003. Experiments were grown on a drought prone soil and employed a mapping population of 46 doubled haploid (DH) lines and their parents, Beaver (+1BL/1RS, soft wheat) and Soissons (1B, hard wheat). The results showed that drought increased hardness in both seasons, but the effect was never sufficient to move a line from the soft class into the hard class. Puroindoline (PIN)-a:b peak height ratio explained ca. 78% of the variation in hardness, and drought also appeared to increase the amounts of PINs in the grain. Minor quantitative trait loci (QTLs) were found for hardness on chromosomes 2A, 2D, 3A and 6D, also associated with QTLs for PINs. Vitreosity also increased in response to drought in both seasons. Variation in vitreosity explained 7–11% of the overall variation in texture within a hardness class, with hardness increasing on average by 2.2 SKCS units for each 10% increase in the proportion of vitreous grains. The relationship between vitreosity and protein content was poor, despite the fact that protein content also increased in response to drought. Minor QTLs associated with both protein content and vitreosity were found on chromosomes 1B, 4D and 5D. A minor QTL for vitreosity was also found on chromosome 2D. However, there appeared to be no direct relationship between alleles at the Ha locus, the gene which controls the difference between hard and soft wheats, and vitreosity. A positive relationship between the presence of the 1BL/1RS translocation and the proportion of vitreous grains was identified, suggesting that vitreosity was strongly linked to changes in protein quality. 相似文献
88.
In this paper we investigated the human thermoregulatory responses, especially core temperature behavior during exercise and
recovery at ambient temperature of 10 °C and 50 % R.H. under the conditions of wearing three kinds of clothing with same weight
and different constructions. Six healthy men wore three kinds of clothing: one insulating the upper half of the body thinly
and the lower half of the body heavily (clothing A, the weights in the upper and lower halves of the body were 489 g and 1278
g, respectively.), the second one insulating the upper half of the body heavily and the lower half of the body thinly (clothing
B, 1212 g and 559 g, respectively.), and the third one insulating the upper and lower halves of the body moderately (clothing
C, 899 g and 879 g, respectively.). The level of rectal temperature was the greatest during exercise in clothing C and the
lowest during recovery in clothing A. The increasing and decreasing rates of core temperature during exercise and recovery,
respectively, were the smallest in clothing B. These findings are discussed in terms of different cooling efficiency from
the lower extremities and disfunction of counter current heat exchange system among clothing A, B, and C. 相似文献
89.
Ijeoma C. Akaogu Baffour Badu‐Apraku Pangirayi Tongoona Hernan Ceballos Vernon Gracen S. K. Offei Daniel Dzidzienyo 《Plant Breeding》2019,138(5):546-552
Striga hermonthica can cause as high as 100% yield loss in maize depending on soil fertility level, type of genotype, severity of infestation and climatic conditions. Understanding the mode of inheritance of Striga resistance in maize is crucial for introgression of resistance genes into tropical germplasm and deployment of resistant varieties. This study examined the mode of inheritance of resistance to Striga in early‐maturing inbred line, TZdEI 352 containing resistance genes from Zea diploperennis. Six generations, P1, P2, F1, F2, BC1P1 and BC1P2 derived from a cross between resistant line, TZdEI 352 and susceptible line, TZdEI 425 were screened under artificial Striga infestation at Mokwa and Abuja, Nigeria, 2015. Additive‐dominance model was adequate in describing observed variations in the number of emerged Striga plants among the population; hence, digenic epistatic model was adopted for Striga damage. Dominance effects were higher than the additive effects for the number of emerged Striga plants at both locations signifying that non‐additive gene action conditioned inheritance of Striga resistance. Inbred TZdEI 352 could serve as invaluable parent for hybrid development in Striga endemic agro‐ecologies of sub‐Saharan Africa. 相似文献
90.