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2.
The current study compared beef production, quality and fatty acid (FA) profiles of yearling steers fed a control diet containing 70 : 30 red clover silage (RCS) : barley-based concentrate, a diet containing 11% sunflower seed (SS) substituted for barley, and diets containing SS with15% or 30% wheat dried distillers’ grain with solubles (DDGS). Additions of DDGS were balanced by reductions in RCS and SS to maintain crude fat levels in diets. A total of two pens of eight animals were fed per diet for an average period of 208 days. Relative to the control diet, feeding the SS diet increased (P<0.05) average daily gain, final live weight and proportions of total n-6 FA, non-conjugated 18:2 biohydrogenation products (i.e. atypical dienes) with the first double bond at carbon 8 or 9 from the carboxyl end, conjugated linoleic acid isomers with the first double bond from carbon 7 to 10 from the carboxyl end, t-18:1 isomers, and reduced (P<0.05) the proportions of total n-3 FA, conjugated linolenic acids, branched-chain FA, odd-chain FA and 16:0. Feeding DDGS-15 and DDGS-30 diets v. the SS diet further increased (P<0.05) average daily gains, final live weight, carcass weight, hot dressing percentage, fat thickness, rib-eye muscle area, and improved instrumental and sensory panel meat tenderness. However, in general feeding DGGS-15 or DDGS-30 diets did not change FA proportions relative to feeding the SS diet. Overall, adding SS to a RCS-based diet enhanced muscle proportions of 18:2n-6 biohydrogenation products, and further substitutions of DDGS in the diet improved beef production, and quality while maintaining proportions of potentially functional bioactive FA including vaccenic and rumenic acids.  相似文献   
3.
Several apoplastic enzymes have been implicated in the control of elongation growth of plant cells. Among them, peroxidases contribute to both loosening and stiffening of the cell wall. They appear to be regulated by various mechanisms, including the action of extracellular inhibitors. To obtain evidence of the role of the enzyme–inhibitor interaction during leaf development, the intercellular washing fluids from Helianthus annuus leaves of different ages were isolated using standard methods of vacuum infiltration and centrifugation. Peroxidase activities, assessed using tetramethylbenzidine as substrate, increased during leaf development, reaching a maximum value after the leaves were fully expanded. An inhibitor, chemically characterised as ascorbate, co‐localised with the enzyme in the apoplast. Moreover, there was a strong negative correlation between the action of peroxidase and the micromolar concentration of ascorbate in the apoplastic fluid. The results show that in growing leaves, the in planta ascorbate concentration is able to restrain peroxidase enzyme activity. Then, at the time of growth cessation, the loss of extracellular ascorbate relieves the inhibition on this enzyme that contributes to wall fixation.  相似文献   
4.
Series of nanoporous carbons are prepared from sunflower seed shell (SSS) by two different strategies and used as electrode material for electrochemical double-layer capacitor (EDLC). The surface area and pore-structure of the nanoporous carbons are characterized intensively using N2 adsorption technique. The results show that the pore-structure of the carbons is closely related to activation temperature and dosage of KOH. Electrochemical measurements show that the carbons made by impregnation-activation process have better capacitive behavior and higher capacitance retention ratio at high drain current than the carbons made by carbonization-activation process, which is due to that there are abundant macroscopic pores and less interior micropore surface in the texture of the former. More importantly, the capacitive performances of these carbons are much better than ordered mesoporous carbons and commercial wood-based active carbon, thus highlighting the success of preparing high performance electrode material for EDLC from SSS.  相似文献   
5.
采用RT-PCR和RACE技术从观赏向目葵‘闽葵3号’黄色花瓣中克隆到类胡萝卜素合成途径关键基因HaPDS的cDNA,该cDNA全长2017bp,具有一个1710bp的完整开放阅读框(ORF),编码一个570个氨基酸的蛋白质。序列分析表明,HaPDS编码的氨基酸序列与其他植物的PDs蛋白具有很高的同源性,在N-端有一个辅助因子结合结构域,C-端有一个类胡萝卜素结合域。系统进化树分析显示,观赏向日葵HaPDS与万寿菊、菊花蛋白亲缘关系较近。实时荧光定量RT-PCR技术分析表明,胁肋路因在花发育的盛花期表达量最高;不同组织中的表达量舌状花瓣〉苞片〉叶片〉绿色管状花〉黑色管状花:随着基因表达量的增加,花色由白色到黄色、金黄色转变。  相似文献   
6.
The acclimation in relationship with virulence cost was analysed for seven Plasmopara halstedii (sunflower downy mildew) isolates including five progeny isolates of several races descending from two parental isolates of races 100 and 710. Aggressiveness criteria were analysed in one sunflower inbred line showing a high level of quantitative resistance. Isolates of races 100 and 3xx were characterised with shorter latent period and higher sporulation density than isolates of races 7xx. All isolates showed high percentage infection values and caused a large reduction in seedling size except for one isolate involved in dwarfing. The seven isolates were divided, according to their virulence and aggressiveness, into two main groups as more aggressive isolates of the 100 and 3xx races which do not overcome the sunflower differential host D3, and less aggressive isolates of 7xx races which can overcome D3. Consequently, the 100 and 3xx avirulent races had a virulence cost measured by differences in aggressiveness (from 45.5 to 76.3%) compared to 7xx virulent races carrying unnecessary virulence gene.  相似文献   
7.
Abstract

Leaf blight caused by Alternaria helianthi (Hansf.) Tubaki & Nishihara, is the major disease of sunflower affecting the successful cultivation across India. Five individual fungicides and two combination fungicides were evaluated against this pathogen in laboratory and in field experiments. Among them, the combination of carbendazim + mancozeb completely (100%) inhibited the mycelial growth of A. helianthi, irrespective of the concentrations tested followed by carbendazim alone and metalaxyl + mancozeb under in vitro condition. In field conditions, the combination of carbendazim + mancozeb was found to be highly effective in reducing the leaf blight disease of sunflower in all the three experiments as compared to other fungicides and unsprayed control. The reduction of Alternaria leaf blight was also directly associated with an increase in seed yield. The economics of the fungicides spray has been worked out and the benefit cost ratio for the combination of carbendazim + mancozeb at 2.0 g/l was 7.1 as compared to unsprayed control. The overall analysis of the results revealed that the combination of carbendazim + mancozeb at 2.0 g/l can be used for the management of foliar diseases such as Alternaria leaf spot/blight in agricultural crops.  相似文献   
8.
Sunflower is one of the most important oilseed crops, which is grown in many countries. Increasing demand to use sunflower oil has expanded the under cultivation area throughout the world. Sunflower viruses have been reported as one of the pathogens that reduce the quantity and the quality of this product in a number of countries. In our research to study the occurrence and distribution of viruses in sunflower fields of Iran, 562 samples were collected from different fields in Kerman and Isfahan provinces during growing seasons from 2009 to 2011. Potato virus Y (PVY), Cucumber mosaic virus (CMV) and Tomato spotted wilt virus (TSWV) were detected by double antibody sandwich enzyme-linked immunosorbent assay. Also, numbers of samples were positive for infection to potyviruses (except PVY) in antigen-coated-plate enzyme-linked immunosorbent assay test using potyviruses general antiserum. Infected plants had symptoms like mosaic, yellowing, deformation, necrotic and chlorotic lesions and mottling on leaves and stunting. The infection rates of potyviruses, PVY, CMV and TSWV in Isfahan province were 33, 22, 4.18 and 3.25% of collected samples, respectively. The corresponding rates for samples from Kerman province were 15, 5, 0.8 and 0.4% of collected samples. According to these results, viral infection in Isfahan province was more than surveyed in Kerman province during the mentioned period of three years. Furthermore, generally there was a decrease in the percentage of viral infection during this three growing seasons in both provinces. This is the first report of the detection of CMV and TSWV in sunflower fields of Isfahan and Kerman and first report of PVY in Isfahan.  相似文献   
9.
Sunflower cultivation is affected seriously by Sclerotinia sclerotiorum (Lib.) de Bary in Iran, particularly north-western areas. Because of economic and environmental harms by chemical control, it is necessary to develop cultivars with adequate genetic resistance for reduction of yield losses. The purpose of this study was to find an effective method of inoculation with S. sclerotiorum under field evaluations. Three stem-inoculation techniques including: 1 – mycelium plug, 2 – oxalic acid solution (OAS) and 3 – infested wheat seeds with Sclerotinia mycelium were employed under field conditions. Four genotypes including Ghalami (local variety in market), Confeta, Allstar and Master were used in this study. The lesion length, lesion width and lesion as up and down leading on the stem from inoculation site were measured after 3, 7, 10 and 14 days of inoculation. The analysis of variance showed significant difference between all employed techniques and incubation days after inoculation. Mycelial plug (MP) inoculation technique produced significantly more developed lesions on the treated stems. In spite of this effect, Master variety demonstrated reasonable resistance reaction against the disease. The progress of disease in wounded treatments was also faster than the non-wounded ones. And, the shortest time to obtain significant differences between varieties was 10?days after inoculation. By comparison of results of lesion length at flowering and seed-filling stages, the more obvious effectiveness of the disease was observed at the second stage. Finally, there were negative correlations between mean temperature and mean lesion length in all three inoculation methods.  相似文献   
10.
The effects of adrenalectomy on growth, some enzyme activities in the liver and kidney, and urinary excretion of urea, creatinine and creatine were investigated in rats fed the 10% casein diets containing 7% glycine with or without l-arginine and l-methionine (10C, 10C7G and 10C7ArgMet).

Body weight gains of the intact 10C and 10C7GArgMet groups were almost same as the corresponding adrenalectomized groups. The body weight of the adrenalectomized 10C7G group was extremely decreased though that of the intact 10C7G group was maintained almost constant; but the decrease was recovered by the administration of hydrocortisone. The activities of liver arginase and carbamylphosphate synthetase were not affected by those diets. Liver serine dehydratase and ornithine δ-aminotransferase activities were increased in the intact 10C7G and 10C7GArgMet groups, but these increases were depressed by adrenalectomy. Glutamate-pyruvate transminase activities in the liver of intact 10C7G and 10C7GArgMet groups were also enhanced, but were extremely decreased in the corresponding adrenalectomized groups. Kidney transamidinase activity was not affected by adrenalectomy. The amount of urinary excreted urea was almost unchanged by adrenalectomy, but was increased by hydrocortisone administration. The amounts of excreted creatine of the adrenalectomized groups were generally larger than the corresponding intact groups, but slightly decreased by the administration of hydrocortisone. The amount of excreted creatinine was not generally affected by adrenalectomy.  相似文献   
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