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991.
为研究半滑舌鳎(Cynoglossus semilaevis)vasa(Csvasa)基因调控区的功能,在已克隆的Csvasa基因编码序列的基础上,采用基因组步移和PCR扩增的方法克隆得到Csvasa调控区,通过生物信息学方法分析vasa基因5′区,并构建了含Csvasa基因调控区的绿色荧光蛋白(GFP)表达载体(p Csvasa-GFP-T),进一步通过显微注射技术初步验证调控区的驱动活性。结果表明,通过基因组步移和PCR扩增获得Csvasa 5′区5 166 bp和3′区1 655 bp,利用在线生物信息学软件对5′区序列进行分析,发现在转录起始点上游26 bp处存在保守的TATA框,以及潜在的转录因子结合点如SRY、Oct-1、Sox-5、CREB、GATA、AP-1、C/EBP、Sp-1、c-Myc、HNF、NKX2-5、V-Myb等。通过显微注射技术,将所构建的p Csvasa-GFP-T表达载体注射于青鳉(Oryzias latipes)受精卵并进行培养观测,发现Csvasa调控区能够驱动GFP在青鳉胚胎内表达,荧光表达率为81%。将有荧光的胚胎培养为成鱼,检测外源基因的整合率为11.5%。这些结果为进一步研究半滑舌鳎原始生殖细胞(PGCs)的标记、追踪和操作研究以及半滑舌鳎的性别控制等奠定了基础。 相似文献
992.
993.
Purpose
Carbon nanomaterials (CNMs) have attracted a great deal of research interest for their potential environmental applications because of their unique properties. Adsorption of organic chemicals on CNMs was reported to be important in controlling their environmental risks. However, the kinetics of the adsorption is hardly investigated in literature. The objective of this work was, therefore, to quantitatively describe the sorption kinetics of 17 α-ethinyl estradiol (EE2) and bisphenol A (BPA) on CNMs as compared to activated carbon (AC). 相似文献994.
Ruijuan Li Jinfeng Zhao Chuanfan Sun Wenjing Lu Chengjin Guo Kai Xiao 《Frontiers of Agriculture in China》2010,4(2):195-209
As a kind of enzyme widely existing in eukaryotic species, especially in grains and oil seeds, phytases play an important
role in the degradation of some phosphates containing organic molecules. So far, phytases derived from various species have
been successfully used as animal feed additives. It has also been experimentally verified that phytases have a potential use
in generating crop germplasm with high phosphorus use efficiency, based on their biochemical role in releasing Pi from the
phytate and its derivatives. In this paper, the biochemical properties, molecular characterizations, functions and the potential
application perspective of phytases are reviewed and commented on, aiming at the further exploration of the biochemical and
molecular characterizations, and promotion of the application of phytases, a kind of important enzyme possessing potential
use in animal feeding and creation of high P use crop cultivars, in the future. 相似文献
995.
996.
生物炭表面水溶活性分子可以有效提高水稻的耐旱性 总被引:1,自引:0,他引:1
生物炭是一种可以改良土壤、增强作物产量和提升作物品质的新型农林废弃物再利用材料。本研究通过振荡方式制备生物炭浸提液,利用水培系统培养水稻幼苗,以20%PEG6000、300 mmol/L和500 mmol/L甘露醇模拟干旱胁迫,研究生物炭表面水溶活性分子对水稻幼苗抗旱性的影响。研究结果发现:生物炭浸提液可有效缓解干旱胁迫造成的水稻种子萌发和幼苗生长抑制,缓解叶绿素含量、鲜重及存活率的降低,同时可以降低体内的活性氧积累等。实时定量RT-PCR检测表明生物炭浸提液促进干旱胁迫响应标志基因的表达量。研究结果说明生物炭浸提液可以提高干旱胁迫下水稻幼苗的抗氧化能力,进一步提高水稻幼苗对干旱胁迫的耐受性。 相似文献
997.
L. Song D.‐W. Zhang F.‐M. Li X.‐W. Fan Q. Ma N. C. Turner 《Journal of Agronomy and Crop Science》2010,196(5):323-335
Competition for water generates a classic aspect of the tragedy of the commons, the ‘race for fish’, where crops must allocate more resource to acquisition of the limiting resource than is optimal for crop yield allocation. A pot experiment using a simple additive (target–neighbour) design was conducted to examine the above‐ground and below‐ground growth of three spring wheat (Triticum aestivum L.) cultivars when grown alone and in mixtures at three levels of water availability. The effects of competition and water availability were compared by observing patterns of growth, biomass allocation and below‐ground outcomes. Competitive interactions were investigated among cultivars ‘HST’, ‘GY602’ and ‘LC8275’, target plant of each cultivar grown without neighbouring plants are referred to herein as control plant and one target plant of each cultivar sown surrounded either by same or another cultivar as intra‐ or inter‐cultivar competition. Competitive ability was assessed as the response ratio (lnRR) between the target plant surrounded by six other plants and the target plant in isolation. Our results showed that the cultivar ‘HST’, released over a century ago, produced a higher biomass and grain yield than the more recently released cultivars ‘LC8275’ and ‘GY602’ when grown as isolated plants with sufficient water supply. However, competition for resources from neighbours led to target plant biomass and grain yield being significantly reduced relative to controls in all three cultivars, particularly in ‘HST’. When subjected to intra‐cultivar competition, the two recently released cultivars ‘LC8275’ and ‘GY602’ had higher grain yields and water use efficiency for grain than ‘HST’ in all three water regimes. The landrace ‘HST’ had better and significantly linear relationships between biomass and biomass allocation, root length and specific root length, whereas the recent and modern cultivars had much more water‐related species‐specific changes in root morphology and allocation patterns. These results suggest that crop traits that influence competitive ability, such as biomass allocation to roots and root plasticity in response to drought have changed in modern wheat cultivars because of breeding and selection. 相似文献
998.
Li Xiaofei Han Yingchun Wang Guoping Wang Zhanbiao Feng Lu Yang Beifang Fan Zhengyi Lei Yaping Xiong Shiwu Xing Fangfang Li Yabing 《棉花学报》2013,32(5):472-482
Cotton-based intercropping systems are one of modern agriculture farming systems aiming at improving overall economic profitability of cotton field, which not only release the competition for land between other crops and cotton and increase growing area and yield of both crops, but also represent a mechanistic approach to reconciling crop production and biodiversity conservation. Recently, cotton-based intercropping systems have been widely focused and applied. Here, we reviewed the potential of cotton-based intercropping systems to reinforce agroecosystem services and functioning, including promoted plant biodiversity, improved overall productivity and economic profits, increased light use efficiency, improved cotton quality, reduced pest and disease occurrence, and suppressed weed growth. Further, the underlying mechanisms behind the enhancement of agroecosystem services and functioning by cotton-based intercropping systems through niche complementarity, interspecific facilitation, and allelopathy between intercropped species were summarized in the paper. Finally, the research prospects were also pointed out. 相似文献
999.
1000.