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981.
DNA甲基化是表观遗传学的研究热点之一.为了探索填饲是否能够引起朗德鹅Anser anser)肝脏脂类代谢中DNA甲基化水平以及基因表达量的变化和DNA甲基化修饰作用和基因表达之间的关系.本研究运用焦磷酸测序技术分析鹅肝脏硬脂酞辅酶A去饱和酶5基因(stearovl-CoA desaturase 5,SCD5)、固醇调节元件结合蛋白2基因(sterol regulatory element-binding protein 2,SREBP2)和超长链脂肪酸延伸酶6基因(elongase of very long chain fatty acids 6,ELOVL6)的甲基化水平,再运用qRT-PCR技术进行定量验证.结果显示,SCD5、SREBP2和ELOVL6各2个片段的甲基化水平均在20%以上,均属于高甲基化状态;对照组3个基因各2个片段的甲基化水平均高于填饲组,填饲组与对照组的SCD5-1S和SREBP2-1S片段甲基化差异显著(P<0.05),SREBP2-2S片段甲基化差异极显著(P<0.01),SCD5-2S、ELOVL6-1S和ELOLV6-2S片段甲基化差异不显著(P>0.05);填饲组SCD5和ELOVL6的mRNA表达量均高于对照组,而SREBP2在填饲组的mRNA表达量显著低于对照组(P<0.05).综合各项指标,填饲引起鹅肝脏组织SCD5、SREBP2和ELOVL6甲基化水平降低,SCD5和ELOVL6 mRNA表达量上升,SREBP2的mRNA表达量降低,表明SCD5和ELOVL6的甲基化修饰对mRNA的表达起反向调控的作用.本实验结果为表观遗传学上DNA甲基化研究方法提供参考,为选育鹅肥肝高产高质系提供重要的分子遗传学依据,也为人类肥胖症和脂肪肝等代谢疾病的研究提供理论依据. 相似文献
982.
The present study was conducted to assess the effect of soil salinity on yield attributes as well as nutrient accumulation in different plant parts of seven Brassica cultivars from two different species raised in pot culture experiment with two levels of salinity treatments along with control corresponding to soil electrical conductivity (EC) values of 1.65 (S0), 4.50 (S1) and 6.76 (S2) dS m?1. The experiment was consisted of twelve replications in a completely randomized design. Imposition of salinity stress affected various yield attributing characters including plant height, which ultimately led to severe yield reduction. However, tolerant cultivars, CS 52 and CS 54 performed better under salt treatment showing lesser yield loss. Salinity stress reduced the nitrogen (N) content in leaves of the Brassica plants, which reflected in decreased seed protein content. Reduced accumulation of iron (Fe), manganese (Mn) and zinc (Zn) was observed in leaf, stem and root at flowering and post-flowering stages, while CS 52 and CS 54 showed less reduction than susceptible cultivars under salinity stress. 相似文献
983.
[目的]监测黄土高原丘陵地区淤地坝在运行中的缓慢和微小变化,及时发现淤地坝的病险隐患,为科学监测、评价陇中黄土丘陵沟壑区乃至西北黄土高原地区淤地坝安全运行提供依据。[方法]通过Nove MS 50全站扫描仪对南湾骨干坝和别杜川骨干坝坝体沉降、水平移位及坝体表面侵蚀进行定期激光扫描,利用等间隔的点云记录坝体和库岸不规则形态。[结果]两期监测对比可以看出,南湾骨干坝接近路面的部分有约1cm的变化,左侧库岸有明显的变化,变化量约为0.8cm,日后极有可能会发生小规模坍塌。别杜川骨干坝整个堤坝在半年的时间内右侧部分约有1~2cm的下降变化,监测结果和管理部门常规监测变形结果一致。[结论]将三维激光扫描技术应用于淤地坝变形监测,可以及时、准确、全面、直观获取淤地坝坝体和库岸表面数据,使得变形监测工作更加全面、便捷、可信。 相似文献
984.
HCO3-同化物在水稻体内的运输分配及其与石灰性土壤水稻耐缺锌的关系 总被引:2,自引:0,他引:2
试验采用营养液培养、同位素示踪方法,研究了HCO3-同化物在缺Zn敏感(IR26)和耐性水稻品种(IR8192-31-2)体内运输和分配的差异。研究结果表明,HCO3-同化物从敏感品种根部向地上部运输较少,在根部积累较多,而耐性品种HCO3-同化物向地上部运输较多,速率较快,而在根部积累较少;施Zn促进敏感品种HCO3-同化物从根部向地上部的运输。敏感品种离体根吸收的HCO3-高于耐性品种,并且HCO3-同化物从根尖向伸长区迁移的速率高于耐性品种。以上结果表明HCO3-同化物运输和分配差异是不同水稻品种对缺锌敏感差异的重要机制之一。 相似文献
985.
Fatemeh Etemadi Masoud Hashemi Omid Reza Zandvakili Yeonhwa Park 《Communications in Soil Science and Plant Analysis》2018,49(16):2064-2073
Increasing the amount of nutrients in plant-based foods will help to improve the nutritional status of people in the World. Faba bean (Vicia faba L.) as a staple food in developing countries has the potential to provide many nutrients in human diets. The objective of this study was to characterize the nutrient concentrations in leaf, pod, and seed of faba bean varieties. A field study was conducted with six faba bean varieties. Variation in the elemental concentrations of nutrients and protein occurred among varieties and different parts of the plants. The highest concentrations of nitrogen, phosphorus, potassium, zinc, or copper and protein were in the seeds. However, the highest accumulation of calcium, magnesium, iron, or manganese was in the leaves. We recommend that faba bean can be considered as a valuable crop in the diet of nutrient-deficient consumers due to high concentration nutrients in edible parts of the plant. 相似文献
986.
气候变化情景下海河流域水文循环变化模拟 总被引:8,自引:0,他引:8
Climate change scenarios, predicted using the regional climate modeling system of PRECIS (providing regional climates for impacts studies), were used to derive three-layer variable infiltration capacity (VIC-3L) land surface model for the simulation of hydrologic processes at a spatial resolution of 0.25° × 0.25° in the Haihe River Basin. Three climate scenarios were considered in this study: recent climate (1961-1990), future climate A2 (1991-2100) and future climate B2 (1991-2100) with A2 and B2 being two storylines of future emissions developed with the Intergovernmental Panel on Climate Change (IPCC) special report on emissions scenarios. Overall, under future climate scenarios A2 and B2, the Haihe River Basin would experience warmer climate with increased precipitation, evaporation and runoff production as compared with recent climate, but would be still likely prone to water shortages in the period of 2031-2070. In addition, under future climate A2 and B2, an increase in runoff during the wet season was noticed, indicating a future rise in the flood occurrence possibility in the Haihe River Basin. 相似文献
987.
988.
《Communications in Soil Science and Plant Analysis》2012,43(2):145-167
Abstract Thirteen fertility trials were made throughout Quebec's corn growing region during 1972–74. These included eleven fertilizer combinations with corn silage as the test crop and were carried out on nine soils. Total dry matter and digestible nutrients (TDN) varied greatly from year to year, though, mean yields increased by 23 and 30 percent respectively with the 50 kg N/ha treatment, compared to control receiving no nitrogen fertilization. However, 150 kg N/ha was required to attain a maximum yield of 1250 kg/ha crude protein. Despite a 0.2 percent nitrate content found in the silage grown on the most northerly site, a 120 kg P/ha combined with 100 kg N and K gave the highest mean TDN production (9580 kg/ha). Potassium fertilization affected plant K content of corn grown at the most northerly site only, where a 0.5 percent was found with the control on a suit containing low potassium levels. Further, striking increases in Ca and Mg concentrations were observed with corn grown on that soil. However, magnesium concentration ranging from 0.11 to 0.14 percent were found with nine field trials out of twelve. Also, low K:(Ca + Mg) ratios were found on three trials, which were increased with potassium fertilization levels of 150 kg K/ha. Accordingly, it is suggested that uptakes of 200, 48, 200, 30 and 30 kg/ha of N, P, K, Ca and Mg are required for good corn silage crops. 相似文献
989.
《Communications in Soil Science and Plant Analysis》2012,43(3):503-511
Abstract The Langmuir parameters of orthophosphate (OP) and pyrophosphate (PP) sorption for the ammoniated tropical soils were determined. Positive linear relationships between OP and PP sorption maxima and amounts of anhydrous NH3 added were noticed. Indexes of bonding energy of OP and PP increased exponentially as ammoniation level of the soils increased from 33 to 100% of ammonia retention capacity. 相似文献
990.
《Communications in Soil Science and Plant Analysis》2012,43(2):135-145
Abstract In laboratory experiments, effects of added Farm Yard Manure (FYM), sorbed cations and cation exchange capacity (CEC) on NH3 volatilization of anhydrous ammonia applied to a Vertisol were studied at 0.3 bar soil Moisture Tension and 25 ± 1°C. On addition of FYM or with increase in CEC the volatilization of retained ammonia was reduced while the effect of the sorbed cations was in the order : K‐Soil > Na‐Soil > Ca‐Soil > Mg‐Soil. The results suggest that the volatilization of retained NH3 followed First order reaction kinetics, with a rapid rate of volatilization in the initial 8 to 10 h followed by a retarded rate up to 144 h. 相似文献