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11.
RNAi系双链RNA诱导同源mRNA降解,导致特定基因表达沉默的一种现象.RNAi技术是通过基因工程防治植物病毒病的最佳途径.由大麦黄矮病毒(Barely yellow dwarfvirus,简称BYDV)引起的禾谷类黄矮病发病面积和危害程度在我国呈加重趋势.BYDV-GAV是当前流行的大麦黄矮病毒株系,本文针对BYDV-GAV复制酶基因序列,构建能在细胞内转录形成发卡RNA双链结构的表达盒,并将其置于中间载体pVec8-2b的T-DNA区,pVec8-2b的另一T-DNA区含有hpt选择报告基因表达盒.具双T-DNA区的病毒复制酶基因发卡RNA高效表达载体已导入根癌农杆菌,可用于诱导植物RNAi,创制无选择标记基因的抗大麦黄矮病转基因作物.  相似文献   
12.
介绍第二次青藏高原综合科学考察研究任务三生态系统与生态安全专题三“农田生态系统与粮食安全”科学考察背景、总体思路、研究内容、研究目标和取得的阶段性进展.该专题针对青藏高原地区农业生产中逐渐出现的局部农田生态系统结构失稳、功能失衡、地力衰退、作物品质下降、农残渐增等问题,在区域尺度上,从耕地肥力和土壤生物、农田植被、农业生产经营管理、作物产量品质和利用、农业气象条件等方面开展科学考察研究,在青藏高原农田生态系统相关生态环境参数的时空特征、分布规律与作物开发利用等考察研究方面取得阶段性重要进展,可为青藏高原农业生态系统可持续经营管理和粮食安全提供数据及科技支撑.(图1参90)  相似文献   
13.
早期结瘤素93(ENOD93)蛋白在植物根瘤形成初期扮演着重要的角色.基于大麦基因组信息鉴定大麦ENOD93基因家族成员,分析其理化特性、进化关系、基因结构、蛋白质结构和启动子顺式作用元件;并分析ENOD93家族在不同组织和不同基因型(籽粒大小)的表达情况.结果显示,大麦ENOD93基因家族有16个成员,均含有ENOD93基因家族特有的保守结构域;编码区长度在207-627 bp之间,外显子数量有1-4个,平均2.75个,且大部分位于细胞膜上;进化树结果表明与水稻、小麦和玉米等禾本科植物ENOD93基因的亲缘关系较近;启动子顺式元件主要有植物生长发育响应元件、胁迫响应元件以及激素响应元件;大部分HvENOD93基因在灌浆期籽粒和大粒材料中表达量较高.推测大麦HvENOD93基因在籽粒大小形成中起关键性作用;另外,结合其他物种相关基因研究结果,共筛选出3个同源基因.(图4表2参45)  相似文献   
14.
Fertility of lateral spikelets determines the two-rowed or six-rowed spikes of barley (Hordeum vulgare L.), which results in significantly different grain yields. The change in row type from two-rowed to six-rowed shows remarkable domestication characteristics. The Qinghai-Tibet plateau has abundant resources of wild and cultivated barley, and is considered one of the centers of domestication and genetic diversity of cultivated barley. In order to obtain a primary understanding of the genetic basis of lateral spike development regulation and the domestication process in cultivated Tibetan barley, an F2 segregation population was constructed by crossing the two-rowed wild barley accession ZYM0083 with the six-rowed landraces Linzhiheiliuleng. Genetic analysis showed that the row type was controlled by a single gene. Using the specific-locus amplified fragment sequencing (SLAF-seq) technology and bulked segregant analysis (BSA), two DNA pools from 22 two-rowed spike individuals and 22 six-rowed spike individuals of the F2 population were constructed and sequenced. A total of 456 691 SLAF tags were obtained. By adopting the ED and SNP index for association analysis, three candidate regions with a 53.84-Mb interval and containing 536 genes were obtained. Four-hundred thirteen, 189, and 160 annotated genes were acquired by GO, KEGG, and COG libraries, respectively. Loci that control lateral spike development in Tibetan barley were primarily mapped by SLAF-seq, and the results presented in this study will facilitate the fine mapping and cloning of target genes. © 2018 Science Press. All rights reserved.  相似文献   
15.
In this study, three different hull-less barley varieties were used to prepare steamed cakes, and their nutritional value, sensory qualities, textural properties, and in vitro starch hydrolysis were evaluated. The results showed that the contents of total dietary fiber (4.50%-5.12%), β-glucan (2.96%-3.96%), total flavonoids (12.56-38.73 mg/100 g), and γ-aminobutyric acid (5.08-9.53 mg/100 g) in the steamed hull-less barley cakes were significantly higher than that in the steamed wheat cake, which were 0.65%, 0.23%, 3.93 mg/(100 g), and 2.63 mg/(100 g), respectively. The sensory properties of steamed ordinary hull-less barley and wheat cakes were not significantly different, but the steamed 08-1127 (waxy hull-less barley) cake was softer and out of shape. The springiness, resilience, cohesiveness, gumminess, and adhesiveness of steamed ordinary hull-less barley cakes were similar to those of steamed wheat cake, while those of steamed 08-1127 cakes were significantly lower than those of steamed ordinary hull-less barley cakes. Steamed hull-less barley cake also showed a maximum starch hydrolysis rate (38.76%-42.74%) that was lower than that of steamed wheat cake (49.92%), and the contents of rapidly (11.58%-13.16%) and slowly digested starch (5.34%-7.56%) were lower than that of steamed wheat cake (17.21% and 15.97%, respectively). In addition, the glycemic (59.37-61.67) and hydrolysis indexes (35.82-40.00) were lower than those of steamed wheat cake (76.66 and 67.30, respectively), and the contents of resistant starch (2.74%-3.55%) were higher than those of wheat steamed cake (1.68%). Therefore, the steamed cakes of ordinary hull-less barley had a higher content of nutritional components than the steamed cake of wheat, and the in vitro starch hydrolysis parameters were better than those of steamed wheat cake. When it is necessary to consider both nutritional and sensory qualities, ordinary hull-less barley can be selected as the raw material for steamed cakes, but waxy hull-less barley is not suitable for making steamed cakes. © 2022 Science Press. All rights reserved.  相似文献   
16.
大麦秆提取液对铜绿微囊藻生长的影响研究   总被引:5,自引:1,他引:5  
张薛  胡洪营  门玉洁 《环境科学学报》2007,27(12):1984-1987
大麦秆提取液是无害、高效的抑藻剂.未过滤大麦秆提取液对铜绿微囊藻的生长有显著的抑制效果,投加比例在10mL·L-1以上时,抑制效果与大麦秆提取液投加浓度之间无明显相关关系,6d后的抑制率均在95%以上,且培养液澄清透明;而通过0.22μm滤膜过滤后的大麦秆提取液对铜绿微囊藻的抑制效果不显著.在投加未过滤大麦秆提取液的培养液中发现大量原生动物,推测原生动物的吞食作用是大麦秆提取液抑制铜绿微囊藻生长的主要原因之一.  相似文献   
17.
研究了江苏省沿海地区覆盖与种植对轻度盐渍化土的水分、盐分、温度、养分等生态环境以及覆盖对大麦生长发育和产量的影响。结果表明:春旱季节,覆盖可以减少土壤水分蒸发,抑制盐分表聚,降低土壤溶液浓度和土表温度,增加土壤有效养分,种大麦后由于植株的蒸腾作用,使土壤水分降低,但土壤盐分和溶液浓度仍低于裸地。盆栽试验结果还显示,覆盖种麦有效地促进了大麦生长发育,显著地提高了大麦产量。  相似文献   
18.
The role of root hairs in Cd acquisition from soil was investigated in three pot experiments using a root hairless mutant (bald root barley, brb) and its wild-type (WT) cultivar of barley (Hordeum vulgare). brb had significantly lower concentrations and lower total amounts of Cd in shoots than WT. The Cd uptake efficiency based on total root length was 8-45% lower in brb than in WT. The difference between brb and WT increased with increasing extractable Cd in soil under the experimental conditions used. Additions of phosphate to soil decreased Cd extractability. Both soil and foliar additions of phosphate decreased root length, and root hair formation in WT. These effects resulted in decreased Cd uptake with increasing P supply. Cd uptake in WT correlated significantly with root length, root hair length and density, and soil extractable Cd. Root hairs contribute significantly to Cd uptake by barley.  相似文献   
19.
Corn buntings Miliaria calandra were abundant throughout arable agricultural landscapes in Europe, but have catastrophically declined since the mid 1970s with changes in farming practice and now give serious conservation cause for concern. Corn buntings declined in Denmark during 1976–1993, but (almost unique in Europe) have since increased (by up to 11% per annum) in some areas without specific conservation recovery actions. Based on breeding bird surveys in the mid 1990s, highest corn bunting densities occurred on mixed agriculture in west Denmark (Jylland); the species was rarer or absent in regions of highest arable land cover. Corn bunting density and extent of rotational and permanent grassland were correlated, but not with spring sown barley (all known to constitute important corn bunting winter habitat). The extent of spring barley rapidly declined in Denmark during the 1980s, but since 1990, most counties have since shown 2–3% annual increases in this crop, except in Nordjylland, where high densities of corn buntings have remained stable. Elsewhere in Jylland, corn buntings have increased in counties supporting highest densities during the mid 1990s, contrasting stable or declining trends in south and east Denmark where densities were originally lower. After dramatic decreases everywhere in Denmark, corn buntings retain highest breeding densities associated with mixed agriculture, especially where grassland and spring sown barley remained in greatest extent. Although purely based on land use correlation and bird surveillance, these results show an association between mixed farming and favourable conservation status of a species now red-listed throughout much of Europe. Further investigations of habitat use at small spatial scales and throughout the annual cycle are urgently required to better enlighten specific recommendations for wider applicability of guidelines for corn bunting recovery actions elsewhere.  相似文献   
20.
青藏高原青稞B组醇溶蛋白遗传多样性研究   总被引:5,自引:0,他引:5  
报道了青藏高原青稞B组醇溶蛋白的遗传多样性.在66份青藏高原青稞材料中,共有15种不同条带、29种不同条带组合,表明青藏高原青稞材料具有丰富的多态性.不同来源的群体材料间遗传多态性存在差异,西藏育成品种的多态性略低于四川农家品种,人工选择使其遗传多态性减弱.聚类分析将材料分成3组,材料聚类与材料来源地没有明显的相关性.图3表5参26  相似文献   
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