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First records of Pityophthorus solus (Blackman, 1928 ) (Coleoptera: Curculionidae: Scolytinae) for Europe are reported. Twenty one specimens were obtained unintentionally during surveys for Ips sexdentatus (Boemer, 1767) and for Pityophthorus juglandis Blackman, 1928 using multiple funnel traps baited with specific attractants for both species in the Basque Country (Northern Spain). 相似文献
884.
Huanglongbing (HLB) is a systemic disease of citrus caused by phloem‐limited bacteria ‘Candidatus Liberibacter’ spp. with ‘Ca. Liberibacter asiaticus’ (Las) the most widespread. Phloem‐limited bacteria such as liberibacters and phytoplasmas are emerging as major pathogens of woody and herbaceous plants. Little is known about their systemic movement within a plant and the disease process in these tissues. Las movement after initial infection was monitored in leaves and roots of greenhouse trees. Root density, storage starch content, and vascular system anatomy in relation to Las presence in field and greenhouse trees, both with and without symptoms, showed the importance of root infection in disease development. Las preferentially colonized roots before leaves, where it multiplied and quickly invaded leaves when new foliar flush became a sink tissue for phloem flow. This led to the discovery that roots were damaged by root infection prior to development of visible foliar symptoms and was not associated with carbohydrate starvation caused by phloem‐plugging as previously hypothesized. The role of root infection in systemic insect‐vectored bacterial pathogens has been underestimated. These findings demonstrate the significance of early root infection to tree health and suggest a model for phloem‐limited bacterial movement from the initial insect feeding site to the roots where it replicates, damages the host root system, and then spreads to the rest of the canopy during subsequent leaf flushes. This model provides a framework for testing movement of phloem‐limited bacteria to gain greater understanding of how these pathogens cause disease and spread. 相似文献
885.
Kiah Smith Geoffrey Lawrence Amy MacMahon Jane Muller Michelle Brady 《Agriculture and Human Values》2016,33(1):45-60
This paper provides new insights into the food security performance of long and short food chains, through an analysis of the resilience of such chains during the severe weather events that occurred in the Australian State of Queensland in early 2011. Widespread flooding cut roads and highways, isolated towns, and resulted in the deaths of people and animals. Farmlands were inundated and there were food shortages in many towns. We found clear evidence that the supermarket-based (long) food chain delivery system experienced significant difficulties in supplying food to flood-affected towns. In contrast, more localized (short) food supply chains—which relied upon supply from growers in peri-urban areas and community-based food initiatives—remained largely intact, and provided food at a time when the supermarkets were limited in their ability to respond to consumer demand. However, on closer examination of food distribution during flooding in the regional city of Rockhampton and in the State capital, Brisbane, the demarcation of success between “long” and “short” food chains became blurred. Both types of food supply chains shared some key resilience characteristics in responding to crisis but diverged in other important ways. We argue that conceptualizing food chains in terms of key elements of resilience—scale, diversity, flexibility and cohesion—may be more fruitful than the short-long dichotomy alone. This approach is particularly useful when prioritizing food security as the basis for evaluating food system sustainability in a context of predicted increases in extreme weather events and future climate change. 相似文献
886.
Interspecific hybrids were produced from reciprocal crosses between Brassica napus (2n = 38, AACC) and B. oleracea var. alboglabra (2n = 18, CC) to introgress the zero-erucic acid alleles from B. napus into B. oleracea. The ovule culture embryo rescue technique was applied for production of F1 plants. The effects of silique age, as measured by days after pollination (DAP), and growth condition (temperature) on the
efficiency of this technique was investigated. The greatest numbers of hybrids per pollination were produced under 20°/15°C
(day/night) at 16 DAP for B. oleracea (♀) × B. napus crosses, while under 15°/10°C at 14 DAP for B. napus (♀) × B. oleracea crosses. Application of the ovule culture technique also increased the efficiency of BC1 (F1 × B. oleracea) hybrid production by 10-fold over in vivo seed set. The segregation of erucic acid alleles in the self-pollinated backcross
generation, i.e. in BC1S1 seeds, revealed that the gametes of the F1 and BC1 plants carrying a greater number of A-genome chromosomes were more viable. This resulted in a significantly greater number
of intermediate and a smaller number of high-erucic acid BC1S1 seeds. 相似文献
887.
Kalt W Blumberg JB McDonald JE Vinqvist-Tymchuk MR Fillmore SA Graf BA O'Leary JM Milbury PE 《Journal of agricultural and food chemistry》2008,56(3):705-712
Dietary intervention with anthocyanins may confer benefits in brain function, including vision. Research to date indicates that animals have only a limited capacity to absorb anthocyanins, compared to other types of flavonoids. Pigs, which are a suitable model for human digestive absorption, were used to examine the deposition of anthocyanins in tissues including the liver, eye, and brain tissue. Pigs were fed diets supplemented with 0, 1, 2, or 4% w/w blueberries ( Vaccinium corymbosum L. 'Jersey') for 4 weeks. Prior to euthanasia, pigs were fasted for 18-21 h. Although no anthocyanins were detected in the plasma or urine of the fasted animals, intact anthocyanins were detected in all tissues where they were sought. LC-MS/MS results are presented for the relative concentration of 11 intact anthocyanins in the liver, eye, cortex, and cerebellum. The results suggest that anthocyanins can accumulate in tissues, including tissues beyond the blood-brain barrier. 相似文献
888.
Andersson AA Lampi AM Nyström L Piironen V Li L Ward JL Gebruers K Courtin CM Delcour JA Boros D Fraś A Dynkowska W Rakszegi M Bedo Z Shewry PR Aman P 《Journal of agricultural and food chemistry》2008,56(21):9767-9776
Ten different barley varieties grown in one location were studied for their content of tocols, folate, plant sterols, alkylresorcinols, and phenolic acids, as well as dietary fiber components (arabinoxylan and beta-glucan). The samples included hulled and hull-less barley types and types with normal, high-amylose, and waxy starch. The aim was to study the composition of raw materials, and therefore the hulls were not removed from the hulled barleys. A large variation was observed in the contents of all phytochemicals and dietary fibers. Two varieties from the INRA Clermont Ferrand barley program in France (CFL93-149 and CFL98-398) had high content of tocopherols and alkylresorcinols, whereas the variety Dicktoo was highest in dietary fiber content and phenolics. Positive correlations were found between 1000 kernel weight, alkylresorcinols, and tocols, as well as between dietary fiber content and phenolic compounds. The results demonstrate that the levels of phytochemicals in barley can likely be affected by breeding and that the contents of single phytochemicals may easily be adjusted by a right selection of a genotype. 相似文献
889.
OBJECTIVE: Among adults with diabetes attempting to change their own diets, we explored how these adults approached providing food for their children and how their children reacted to dietary changes in the household. DESIGN: The research design used semi-structured parallel individual interviews of adults and a child (aged 10-17 years) in their home. Interviews were audio-taped, transcribed, coded and analysed for themes. SUBJECTS: Subjects included families in which one inner-city African American or Latino adult with diabetes had completed a diabetes intervention promoting healthy dietary behaviours. RESULTS: We completed 29 interviews (14 adult-child pairs and one child). Adults approached making dietary changes for themselves and also providing food for their family in different ways, ranging from expecting everyone to eat the same thing to preparing two separate meals. Many children resisted dietary changes while fewer acquiesced. Among children who went along with changes, some reported resisting initially then adjusting, while others did not resist because the food still tasted good or they could obtain preferred foods outside the house. The intersection of adults' meal strategies and children's reactions to the changes can be used to categorise families into different patterns. These patterns highlight the tension between an adult who must make dietary changes to control diabetes and a child who is not necessarily motivated to change. CONCLUSION: From this framework we suggest hypotheses about how these patterns might influence dietary behaviour in adults and children. Understanding these patterns could guide interventions to assist parents in successfully including children in their dietary changes. 相似文献
890.