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61.
Waterlogging is a major constraint of faba bean (Vicia faba L.) production in the highland vertisols of Ethiopia. Genotypes are currently evaluated under both the drained conditions
of Broad Bed and Furrow(BBF) and the undrained flatbeds. The objective of this research was to determine if selection of genotypes
under BBF is efficient for identification of genotypes for the flatbed conditions. Yields under the flatbed conditions were
lower by 20–50% (38% on average) than yields under the BBF. Genetic variation, heritability and predicted genetic gains for
grain yield due to direct selection were also lower under the flatbeds than they are under the BBF. There were good levels
of genetic correlation (r = 0.20–0.75 or0.45 on average) between yield performances under BBF and flatbeds, indicating that
selection under BBF may identify good genotypes for flatbeds and vice versa. There was also high association (r =0.91) between
relative yield reduction under flatbeds and the ratio of the predicted genetic gains from indirect selection under BBF to
the predicted genetic gains from direct selection under flat beds. This indicates that indirect selection under BBF may be
useful to identify better genotypes for flatbed conditions, but the relative efficiency of indirect selection was lower than
direct selection under flatbeds themselves.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
62.
The genetic nature of bacterial wilt resistance in tomato was studied in two crosses based on the number of days of survival
(quantitative) in the field before the appearance of wilt symptoms. Significant differences were observed between generation
means in both crosses (LA 1421 × Cascade and LA 1421 × Caraibo). This study indicates that resistance identified in Lycopersicon
esculentum var. cerasiforme LA 1421 may be different from that derived from L. pimpinellifolium. However, the genetic mechanism
seems to be complex with a duplicate form of epistasis. Results suggest that selection for resistance from crosses between
LA 1421 and Cascade should preferably be delayed until a high level of fixation of genes is attained. The variation observed
in the F2 and BC2 progeny of the Caraibo cross, suggested that genetic combination between the two resistance sources can lead to higher levels
of resistance.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
63.
64.
Seed oils of 11 samples of Capparis ovata and Capparis spinosa from different locations in Turkey were characterized with regard to the composition of fatty acids, tocopherols, and sterols as well as the content of glucosinolates. The oil content of the seeds ranged from 27.3 to 37.6 g/100 g (C. spinosa) and from 14.6 to 38.0 g/100 g (C. ovata). The dominating fatty acid of both species was linoleic acid, which accounted for 26.9-55.3% in C. ovata seed oils and for 24.6-50.5% in C. spinosa seed oils. Oleic acid and its isomer, vaccenic acid, were both found in the seed oils in concentrations between 10 and 30%, respectively. The seed oils of both species were rich in tocopherols with the following composition: gamma-tocopherol, 124.3-1944.9 mg/100 g; delta-tocopherol, 2.7-269.5 mg/100 g; and alpha-tocopherol, 0.6-13.8 mg/100 g. The concentration of total sterols ranged from 4875.5 to 12189.1 mg/kg (C. ovata) and from 4961.8 to 10009.1 mg/kg (C. spinosa), respectively. In addition to sitosterol, which amounted to approximately 60% of the total amount of sterols, campesterol and stigmasterol accounted for 16 and 10% of the total sterols, respectively. The seed oils showed remarkably high contents of Delta5-avenasterol (between 138.8 and 599.4 mg/kg). The total content of glucosinolates of C. ovata and C. spinosa samples was determined as 34.5-84.6 micromol/g for C. ovata and 42.6-88.9 micromol/g for C. spinosa, respectively, on a dry weight basis, with >95% as glucocapperin. 相似文献
65.
Ozgur Aksoy DVM PhD Engin Kilic DVM PhD Cihan Kacar DVM PhD Mahmut Sozmen DVM PhD Nezihe Gokhan DVM Orsan Gungor DVM PhD 《Journal of Equine Veterinary Science》2007,27(6):277-280
This paper describes clinical findings and surgical treatment of a foal with multiple craniofacial defects (glossocheilognathoschisis; congenital midline cleft of the lower lip, mandible and tongue combined with bilateral persistent frenula linguae) admitted to the Surgery Clinics of Faculty of Veterinary Medicine, University of Kafkas, Turkey. A thorough clinical examination revealed cleft of the lower lip and mandible combined with glossoschisis (glossocheilognathoschisis) and bilateral extensive and restrictive membranous band (frenula) of tissue at the base of the tongue. Physical examination and radiography of the other organs and tissues of the foal were within normal limits. After sedation and general anesthesia, the persistent frenulas on the right and left parts of the tongue were transected, starting from normal tongue tissue, with the scissors. The tongue was completely freed after the transection of the remaining part of the frenulum, where right and left frenulas united, and the accompanying mucosal tissue on the mandibular symphysis was removed and underlying bone tissue was superficially curetted. Cerclage wire was placed under the mucosa of the mandible and was then passed among two drilled holes below the two incisors. These two pieces of wire were twisted together and anchored over the labial surface of the mandibular symphysis junction. The mandibular symphysis was then stabilized after cerclage wire tensing. A nasogastric tube was placed to permit enteral feeding. The foal was discharged 5 days after surgery. Telephone follow-up revealed that the foal had died 15 days after the surgical intervention. 相似文献
66.
Cawson Jane G. Hemming Victoria Ackland Andrew Anderson Wendy Bowman David Bradstock Ross Brown Tegan P. Burton Jamie Cary Geoffrey J. Duff Thomas J. Filkov Alexander Furlaud James M. Gazzard Tim Kilinc Musa Nyman Petter Peacock Ross Ryan Mike Sharples Jason Sheridan Gary Tolhurst Kevin Wells Tim Zylstra Phil Penman Trent D. 《Landscape Ecology》2020,35(8):1775-1798
Landscape Ecology - Fire behaviour research has largely focused on dry ecosystems that burn frequently, with far less attention on wetter forests. Yet, the impacts of fire in wet forests can be... 相似文献
67.
ABSTRACT: Substantial debate exists on whether the immune response between sheep resistant and susceptible to gastrointestinal nematodes can be differentiated into a Th1 and Th2 phenotype. The present study addresses the hypothesis that variation in resistance to Teladorsagia circumcincta between DRB1*1101 (associated with reduced faecal egg count and worm burden) carriers and non-carriers is due to a differential interplay in the expression of Th1/Th2 and regulatory T (Treg) related cytokine genes. Lambs from each genotype were either slaughtered at day 0 (un-infected control) or infected with 3 × 104 Teladorsagia circumcincta L3 and slaughtered at 3, 7, 21, and 35 days later. Lambs carrying the DRB1*1101 allele had a significantly lower worm burden (P < 0.05) compared to the non-carriers. Abomasal mucosal cytokine gene expression was evaluated by quantitative real-time PCR and comparison made for time and genotype effects. The response generated varied through the course of infection and was affected by genotype. DRB1*1101 carriers had an up-regulated expression of the Th1-related cytokine genes (IL-1β, TNFα, and IFN-γ) at day 3, but this was replaced by an up-regulated expression of Th2-related cytokine genes (IL-10 and IL-13) and Treg-related cytokine genes (IL-2RA-CD25, TGFα, TGFβ, Arg2, MIF and FOXP3) by day 7. Conversely, in the non-carriers these changes in gene expression were delayed until days 7 and 21 post infection (pi), respectively. It is concluded that resistance to Teladorsagia circumcincta in animals carrying the DRB1*1101 allele is influenced by an earlier interplay between Th1, Th2 and T regulatory immune response genes. 相似文献
68.
Acacia senegal, the gum arabic producing tree, is the most important tree species for the livelihood of the people in South Kordofan State, Sudan. The objective of this study was to determine the optimum tapping date for gum arabic production in the study area. A randomized complete block design experiment with three replications was conducted at (Meari) area for two continuous growing seasons 2008/2009 - 2009/2010. The treatments comprised six tapping dates (1 Oct, 15 Oct, 1 Nov, 15 Nov, 1 Dec, and 15 Dec). Results showed highly significant differences (p < 0.001) in gum arabic yield (g\tree) in all pickings and in the total gum yield between the tapping dates. The results also showed that tapping of trees on 15 October and 1 November gave a higher yield compared to the other dates. The highest gum yield of 1086.6 and 661.2 g/tree was recorded on 15 October and 15 November, while the lowest gum yield of 297.9 g/tree was recorded when the trees were tapped on 1 October. The two highest-yield dates of tapping (15 Oct and 1 Nov) are recommended as the best time for tapping for gum arabic production in South Kordofan State. These results can be used to increase gum arabic production and farmer income in South Kordofan State. 相似文献
69.
库尔勒香梨树干阳阴面形成层温度的对比分析 总被引:3,自引:0,他引:3
采用植物体内温度监测系统,监测了库尔勒香梨树干形成层的温度和主要气象因子,分析了树干阳阴面形成层温度变化特性并探讨了融冻和日灼发生的可能性。结果表明:树干阳阴面形成层温度变化有季节特性,阳面温度变化比阴面强烈,尤其是冬季更加明显;夏季阳阴面温度差异较小;白天树干阳面形成层温度高于阴面,夜间阴面温度略高于阳面;阳面日较差最高值出现在冬季,达33.14℃,比阴面日较差高17.14℃;越冬期间树干阳面日最低温度低于阴面,最高温度高于阴面,说明树干阳面比阴面更容易受到低温冻害和日灼危害;夏季树干阳面形成层日最高温度高于阴面且大于40℃高温持续日数在20d以上,说明树干阳面形成层比阴面更容易受到日灼的危害。 相似文献
70.
The effectiveness of brief (30 or 60 s) immersion in water at 24, 50, 55, 60, 65, or 70 °C was evaluated for the control of brown rot, caused by Monilinia fructicola, on California-grown peaches, nectarines, and plums. Inoculated fruits were treated and either stored at 20 °C for 5 days or at 0 °C and 95% RH for 30 days followed by 5 days at 20 °C to simulate commercial marketing conditions. Immersion in water at 55 °C for 60 s or at 60 °C for 30 or 60 s significantly reduced both decay incidence and severity among the remaining wounds that developed the disease. Water temperatures of 65 °C or higher were phytotoxic and caused moderate to severe surface injuries. Immersion in water at 60 °C for 60 s was effective for plums and it reduced the incidence of brown rot from more than 80% among control fruit to less than 2%. In nectarines, this treatment reduced decay incidence from 100 to less than 5% on fruit stored at 20 °C and from 73 to 28% on cold-stored fruit. Therefore, brief immersion in heated water can be an effective approach to manage postharvest brown rot of stone fruits, especially for the organic fruit industry. 相似文献