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21.
Common bean is one of the widely consumed food security crop in Africa, Asia and South America. It is a rich source of protein, minerals and micronutrients. High genotype by environment interaction is one of the main challenge in breeding for high grain micronutrient concentration. The objective of this study was to estimate SNP markers associated with grain Fe and Zn concentration using 289 common bean genotypes and 11,480 SNP markers. The study revealed that 43 quantitative trait loci (QTLs) were associated with grain Fe and Zn concentration. Five quantitative trait nucleotides (QTNs), that is, QTN Fe_1.1, QTN Fe_6.3, QTN Fe_6.5, QTN Fe_10.3 and QTN Fe_11.6 were detected both at Haramaya and Melkassa locations. Two of the markers, that is, QTN Fe_6.3 and QTN Fe_6.5, were located on chromosome 06 while QTN Fe_1.1, QTN Fe_10.3 and QTN Fe_ 11.6 were residing on chromosomes 01, 10 and 11, respectively. Among these, QTN Fe_11.6 had a large and positive consistent effect across locations. The five stable QTNs along with the potential candidate genes could be used for Fe biofortification through marker assisted selection.  相似文献   
22.
Mammalian herbivores regularly browse plantation seedlings. In many areas, seedlings require some form of protection if they are to survive and grow into a productive plantation. Two general approaches for reducing browsing damage to seedlings are to apply chemical repellents and tree guards. Both methods have existed for a long time, and new variations are constantly being developed. Seedling stocking guards, a type of tree guard, are being used operationally in Tasmania, Australia, but there is limited data quantifying their effectiveness and concerns with negative effects on tree performance. Conversely, although proven effective, repellents are not being used, but are potentially cheaper and less problematic. We therefore aimed to determine which is more effective under operational conditions, whether this effectiveness can be improved or extended, and if either treatment has any effects on seedling form or survival. We planted Eucalyptus nitens seedlings with combinations of repellent and stocking guards in six operational plantations to examine and compare their effectiveness. Seedlings were monitored for 12 months to examine treatment longevity. We found that both stocking guards and repellent significantly reduced and delayed browsing severity, with their effects being additive. No negative effects on growth were evident after 12 months, but adverse effects on seedling form warrant further investigation. Both of these methods can be easily and relatively cheaply applied in the nursery before planting, making them appealing options to reduce browsing. However, the ideal method for a given site will depend upon local browsing intensity.  相似文献   
23.
Browsing by mammalian herbivores is a major problem in plantation forestry. Seedlings are most vulnerable to browsing during establishment, making protection crucial during this period. Aside from reducing herbivore numbers, browsing can be controlled through the application of tree guards or chemical repellents. These methods are generally short-term options. A promising, potentially longer-term method of reducing browsing damage on plantations is to plant individuals with enhanced natural browse resistance. This requires the development of a rapid, cost-effective means of identifying germplasm with enhanced resistance. Here we present such a screening methodology.We planted Eucalyptus globulus seedlings from 22 different seedlots in randomised blocks along edge rows of six operational plantations. Seedlings were monitored for mammal browsing damage and growth for 2 years. Natural variation between E. globulus seedlots resulted in significant variation in the extent to which they were browsed. Differential browsing was evident just 10 weeks after planting, and caused a significant effect on tree growth after 2 years. Differential browsing was thought to be due to variation in levels of plant secondary metabolites (PSMs). The identification and selective planting of high PSM seedlots in high risk areas could be an effective management tool to reduce browsing in plantation forestry.  相似文献   
24.
The pattern of decay developing in Ulmns procera killed by Ceratocystis ulmi was examined. Flammulina velutipes had caused some decay and discolouration in most trees which had been dead for more than two years. Decay caused by Pleurotus sapidus was less common. Pleurotus palmatus was frequently isolated from wood in the upper trunk showing no visible deterioration. Trees should be felled within two years of death in order to retain the value of their timber.  相似文献   
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OBJECTIVE: To compare 3 techniques for ureteroneocystostomy in cats. STUDY DESIGN: Experimental surgical study. ANIMALS: Fifteen adult cats. METHODS: Cats (15) had ureteroneocystostomy with ureteronephrectomy of the contralateral kidney: 5 cats had an intravesical mucosal apposition technique (modified Leadbetter-Politano; intravesical-MA group), 5 cats had extravesical ureteroneocystostomy (modified Lich Gregoir) using a simple continuous suture pattern (extravesical-SC group) and 5 cats had an extravesical technique using a simple interrupted suture pattern (extravesical-SI group). Renal function was evaluated by measuring serum creatinine concentration. Ultrasonographic assessment of the kidney and ureteroneocystostomy site was performed the day after surgery, twice weekly for 3 weeks and once weekly for the remainder of the study. Cats were euthanatized 50 days after surgery. The kidney and ureter removed at surgery, the remaining kidney, ureter, ureteroneocystostomy site, and bladder were examined histologically. RESULTS: Two extravesical-SC cats were euthanatized because of azotemia and uroabdomen, and 1 died acutely at day 4 for unknown reasons. In the intravesical-MA and extravesical-SI cats, the serum creatinine concentration increased after surgery, peaking at a mean (+/-SD) of 9.4+/-2.4 mg/dL and 4.9+/-3.3 mg/dL on day 3, and decreasing to 3.4+/-5.7 mg/dL and 1.5+/-0.4 mg/dL on day 7, respectively. The extravesical-SI technique was associated with consistently lower serum creatinine concentrations for the first week after surgery compared with the other techniques. The mean serum creatinine concentration was within the reference range in cats in the intravesical-MA and extravesical-SI groups by days 10 and 5, respectively. Renal pelvic dilatation occurred in all cats but resolved more rapidly in cats after extravesical techniques. There was no significant difference in serum creatinine concentrations or renal pelvic dilation between the intravesical-MA and extravesical-SI techniques. Bladder mass height at the anastomosis site was significantly larger and persisted for longer with intravesical-MA technique. CONCLUSION: An extravesical-SI technique is seemingly the choice for ureteroneocystostomy in cats with undilated ureters. Renal pelvic dilation on ultrasound examination should be expected after ureteroneocystostomy in cats. CLINICAL RELEVANCE: An extravesical ureteroneocystostomy technique using a simple interrupted pattern for anastomosis should be considered in cats undergoing renal transplantation.  相似文献   
26.
This paper describes three experiments aimed at determining the proportion of dead birds at sea which come ashore and are found by members of the public, and discusses the results in relation to wind velocities. From 11% to 58% of the ringed (Larus spp.) corpses thrown into the Irish Sea between Liverpool and the Isle of Man on three occassions in 1973 and early 1974 were recovered. There were large differences between experiments in the timing of the recoveries, although half usually occurred within 11–14 days of dropping. The resultant wind velocities during the time the first bodies recovered from each experiment were at sea were calculated. Comparison of the observed and expected tracks of these bodies confirmed that the wind was the main factor influencing the direction of drift. Gull corpses drifted at a minimum of 2·55±0·93% of the wind speed, although there was much variation and some travelled at over 4% windspeed. With a few exceptions, the observed distribution of recoveries could be broadley predicted by wind vector analysis. The amount of onshore wind when the bodies had reached coastal waters was not related to the subsequent recovery rates. Further experiments are necessary if some of our findings are to be explained and examination of the effect of tidal cycles on the beaching of corpses would also be of value.  相似文献   
27.
Features of chronic asthma include airway hyperresponsiveness, inflammatory infiltrates, and structural changes in the airways, termed remodeling. The contribution of eosinophils, cells associated with asthma and allergy, remains to be established. We show that in mice with a total ablation of the eosinophil lineage, increases in airway hyperresponsiveness and mucus secretion were similar to those observed in wild-type mice, but eosinophil-deficient mice were significantly protected from peribronchiolar collagen deposition and increases in airway smooth muscle. These data suggest that eosinophils contribute substantially to airway remodeling but are not obligatory for allergen-induced lung dysfunction, and support an important role for eosinophil-targeted therapies in chronic asthma.  相似文献   
28.
The aim of this study was to investigate how three vascular plant species (Calluna vulgaris, Eriophorum angustifolium and Eriophorum vaginatum) colonising an abandoned cutover peatland affect fluxes of recent photosynthate to dissolved organic carbon (DOC), soil and plant respiration and shoot biomass. We used in situ 13CO2 pulse labelling to trace carbon (C) throughout a 65 day pulse chase period. Between 16 and 35% of the pulse of 13C remained in shoot biomass after 65 days with significant differences between C. vulgaris and E. angustifolium (P = 0.009) and between C. vulgaris and E. vaginatum (P = 0.04). A maximum of 29% was detected in DOC beneath labelled plants and losses of 13C from peat respiration never exceeded 0.16% of the original pulse, showing that little newly fixed C was allocated to this pool. There were no significant differences between the different plant species with respect to 13C recovered from DOC or via peat respiration. More C was lost via shoot respiration; although amounts varied between the three plant species, with 4.94–27.33% of the 13C pulse respired by the end of the experiment. Significant differences in 13C recovered from shoot respiration were found between C. vulgaris and E. angustifolium (P = 0.001) and between E. angustifolium and E. vaginatum (P = 0.032). Analysis of δ13C of microbial biomass indicated that recently assimilated C was allocated to this pool within 1 day of pulse labelling but there were no significant differences in the 13C enrichment of the microbial biomass associated with the different plant species. The data suggest that peat respiration represents a small flux of recent assimilate compared to other fluxes and pools and that different vascular plant species show considerable variation in the quantities and dynamics of C allocated to DOC.  相似文献   
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