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111.
真核翻译延伸因子(eukaryotic translation elongation factor,eEFs)是一种重要的多功能调控蛋白,eEF1β是eEF1的组成部分,在蛋白质生物合成过程中发挥着重要的作用。本文通过RT-PCR扩增克隆小麦(Triticum aestivum L.)的eEF1β基因,并命名为TaeEF1β。氨基酸同源性分析发现,TaeEF1β具有高度保守性,且其保守结构域位于137~226 aa处。qRT-PCR结果表明,中国小麦花叶病毒(Chinese wheat mosaic virus,CWMV)侵染小麦植株后,可以诱导TaeEF1β基因转录水平的上调表达。另外,本文也进一步分析了TaeEF1β基因在小麦根、茎、叶的表达水平和CWMV侵染不同时间点的表达情况。 相似文献
112.
113.
桑叶养猪实用技术分为桑树种植技术和桑叶干粉发酵养猪技术两个部分。利用荒地种植桑树,降低生猪养殖饲养成本,桑叶养猪种养结合,成为生态农业典范。桑叶干粉发酵技术,提高了桑叶干粉的可消化率和饲料功能。桑叶干粉发酵料占配方6%~10%,做成桑叶猪饲料,替代3%~5%鱼粉、豆粕等蛋白质饲料,节约了饲料成本。桑叶喂养猪(简称桑叶猪,下同)的猪肉中含有肌苷酸等风味物质,显著提高猪肉胴体品质和猪肉风味。设计猪尿处理,采用红泥膜沼气池降解工程工艺应用后,降解水兑2倍清水对桑树喷灌工艺,减少人工处理劳力和成本费用。设计10%抗非洲猪瘟中药饲料添加剂+桑叶饲料,预期防治非洲猪瘟总效果85%以上。桑叶养猪实用技术可行,供同行参考。 相似文献
114.
Genotypic Variation for Tolerance to Transient Drought During the Reproductive Phase of Brassica rapa
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Y. M. Guo N. C. Turner S. Chen M. N. Nelson K. H. M. Siddique W. A. Cowling 《Journal of Agronomy and Crop Science》2015,201(4):267-279
Brassica rapa L. is a genetically diverse parent species of the allotetraploid species, oilseed rape (B. napus) and a potential source of drought tolerance for B. napus. We examined the effect of a 13‐day drought stress period during the early reproductive phase, relative to a well‐watered (WW) control, on subsequent growth and development in nine accessions of B. rapa and one accession of Brassica juncea selected for their wide morphological and genetic diversity. We measured leaf water potential, stomatal conductance, water use, and leaf and bud temperatures during the stress period and aboveground dry weight of total biomass at maturity. Dry weight of seeds and reproductive tissue were not useful measures of drought tolerance due to self‐incompatibility in B. rapa. The relative total biomass (used as the measure of drought tolerance in this study) of the 10 accessions exposed to drought stress ranged from 47 % to 117 % of the WW treatment and was negatively correlated with leaf‐to‐air and bud‐to‐air temperature difference when averaged across the 13‐day stress period. Two wild‐type (B. rapa ssp. sylvestris) accessions had higher relative total and non‐reproductive biomass at maturity and cooler leaves and buds than other types. We conclude that considerable genotypic variation for drought tolerance exists in B. rapa and cooler leaves and buds during a transient drought stress in the early reproductive phase may be a useful screening tool for drought tolerance. 相似文献
115.
hrpZ_(Psta)在转基因大豆中定量表达与疫霉根腐病和灰斑病抗性相关研究 总被引:1,自引:0,他引:1
以T5转hrpZPsta基因大豆JN29-705-15和JL30-187为材料,利用实时荧光定量PCR技术(Quantitative Real Time PCR,qRT-PCR)检测了目标基因在转基因大豆不同组织中的表达量,分别利用下胚轴侵染法和叶面喷施法鉴定疫霉根腐病抗性和灰斑病抗性,并分析目的基因表达量与疫霉根腐病和灰斑病抗性的相关性。结果表明:hrpZPsta基因在大豆的叶、茎、根、籽粒中均有表达,二个株系平均相对表达量分别为8.2/6.1、0.9/0.7、6.5/4.6和0.8/0.7;T5转hrpZPsta基因大豆抗疫霉根腐病和灰斑病能力与野生型相比均有所提高,JN29-705-15对疫霉根腐病抗性从感病提高到中抗,而JL30-187从中抗提高到抗病;hrpZPsta基因在叶中的表达量也与抗灰斑病能力呈正相关,与病情级别呈极显著负相关。试验结果初步证明了外源基因hrp ZPsta在大豆植株中的表达量与受体植株对疫霉根腐病和灰斑病抗性存在一定的相关性。 相似文献
116.
Evaluating the role of seed priming in improving drought tolerance of pigmented and non‐pigmented rice
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This study was conducted to evaluate the influence of seed priming on drought tolerance of pigmented and non‐pigmented rice. Seeds of pigmented (cv. Heug Jinju Byeo) and non‐pigmented (cv. Anjoong) rice were soaked in water (hydropriming) or solution of CaCl2 (osmopriming). Seeds were sown in soil‐filled pots retained at 70 (well‐watered) and 35% (drought) water‐holding capacity. Drought stress caused erratic and poor stand establishment and decreased the growth of both rice types. More decrease in plant height and leaf area under drought stress was noted in pigmented rice, whereas decrease in root length and seedling dry weight, under drought, was more obvious in non‐pigmented rice. Pigmented rice maintained more tissue water and photosynthesis and had more polyphenols, flavonoids and antioxidant activity than non‐pigmented rice. Seed priming was effective in improving stand establishment, growth, polyphenols, flavonoids and antioxidant activity; however, extent of improvement was more in pigmented rice under drought. In conclusion, drought caused erratic germination and suppressed plant growth in both rice types. However, pigmented rice had better drought tolerance owing to uniform emergence, and better physiological and morphological plasticity. Seed priming was quite helpful in improving the performance of both rice types under drought and well‐watered conditions. 相似文献
117.
New strategies to enhance growth and productivity of food crops in saline soils represent important research priorities. This study has investigated the role of certain priming techniques to induce salt tolerance of bread wheat. Wheat grains were soaked in 0.2 mm sodium nitroprusside as nitric oxide donor (redox priming), diluted sea water (halopriming) and the combination of both (redox halopriming). Grains were also soaked in distilled water (hydropriming); in addition, untreated grains were taken as control. Our results indicated that priming treatments significantly improved all growth traits and increased leaf pigments concentration as compared to the control. Priming treatments markedly enhanced membrane stability index, proline, total soluble sugars and K+ concentration with simultaneous decrease in the concentration of Na+ and malondialdehyde (MDA). Furthermore, yield and yield‐related traits such as plant height, spike length, total number of tillers, 1000‐grain weight, straw and grain yield considerably affected by priming treatments. Moreover, the grain yield of both genotypes was positively affected by redox halopriming treatment. However, the extent of enhancement was more prominent in Gemmiza‐9 (salt sensitive) than that in Sakha‐93 (salt‐tolerant). Overall, this study clearly indicated that redox halopriming treatment is a promising and handy technique to induce salinity tolerance of wheat genotypes. 相似文献
118.
Modelling Wheat Stomatal Resistance in Hourly Time Steps from Micrometeorological Variables and Soil Water Status
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An accurate estimation of stomatal resistance (rS) also under drought stress conditions is of pivotal importance for any process‐based prediction of transpiration and the energy budget of real crop canopies and quantification of drought stress. A new model for rS was developed and parameterized for winter wheat using data from field experiments accounting for the influences of net radiation (RNet), air temperature (TAir) and vapour pressure deficit of the atmosphere (VPD) interacting with an average water potential in the rooted soil (ψRootedSoil). rS is simulated with a limiting factor approach as maximum of the metabolic (related to photosynthesis) and hydraulic (related to drought stress) acting influences assuming that, if drought stress occurs, it will dominate stomatal control: rS = max(rS(TAir), rS(RNet), rS(VPD, ψRootedSoil)). This transitional approach is suited to reproduce measured daily time courses of rS with a varying accuracy for the single measurement dates but performed satisfactorily for the whole data set (r2 = 0.63, RMSE = 59 s m?1, EF = 0.60). This new semi‐empiric approach calculates rS directly from external environmental conditions. Therefore, it can be easily implemented in existing model frameworks as link between operational crop growth models that use the concept of radiation use efficiency instead of mechanistic photosynthesis modelling and soil–vegetation–atmosphere transport models. 相似文献
119.
水肥耦合对小麦/玉米带田产量及构成因素的影响 总被引:5,自引:0,他引:5
采用"3414"最优回归设计方案,于2007-2008年在甘肃省农业科学院张掖节水试验站,开展不同水肥耦合处理小麦/玉米带田产量效应研究。结果表明,不同水肥耦合模式对小麦/玉米带田产量的影响较大,其差异达极显著水平。其中,氮肥对产量的贡献最大,水分次之,磷肥最小,氮肥对带田混合产量的绝对贡献率达79.4%,而水分对带田混合产量的绝对贡献率达为52.9%;水肥耦合效应为:水氮耦合水磷耦合氮磷耦合;获得高产量12 952.5~13 880.0kg/hm2的施氮量为420~630kg/hm2、灌水量为5 550~6 750m3/hm2、施磷量为120kg/hm2。相关分析表明,施氮量和灌水量与间作玉米的穗粒数、千粒质量、穗粒质量、株高均呈极显著正相关,施氮量与间作小麦的穗粒质量、穗粒数呈极显著正相关。 相似文献
120.
根据铜仁烤烟单叶重的调查数据,认真梳理了铜仁烤烟单叶重的现状,分析了铜仁烤烟单叶重存在的问题,从烟叶收购政策和烟叶生产技术两个方面有针对性的提出提升铜仁烟叶质量的对策,为铜仁烤烟产业的持续健康发展提供理论指导。 相似文献