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151.
《Free radical research》2013,47(4-5):303-312
The effect of a variety of proteins and amino acids was investigated on oxygen free radical activity as assessed by copper/hydrogen peroxide induced benzoate hydroxylation as well as copper-catalysed ascor-bate autoxidation. Serum albumins from a variety of species (human, bovine and dog) had both inhibitory and stimulatory effects depending on the molar copper to protein ratio; low ratios were inhibitory and high stimulatory. Some other proteins tested (lysozyme, soybean trypsin inhibitor and conalbumin) also had dual (inhibitory and stimulatory) effects, as did both histidine and polyhistidine, but all effects occurred at different molar ratios presumably dependent on the relative affinities for the copper ions. In contrast, metallolhioncin and cacruloplasmin, proteins specialised to bind copper in vivo had no stimulatory effects. In this paper we show that in addition to their fairly well documented inhibitory effects, under certain conditions some proteins also stimulate radical reactions. The possible role of this phenomenon in vivo is discussed. 相似文献
152.
Environmental adaptation of crops is essential for reliable agricultural production and an important breeding objective. Genebanks provide genetic variation for the improvement of modern varieties, but the selection of suitable germplasm is frequently impeded by incomplete phenotypic data. We address this bottleneck by combining a Focused Identification of Germplasm Strategy (FIGS) with core collection methodology to select soybean (Glycine max) germplasm for Central European breeding from a collection of >17,000 accessions. By focussing on adaptation to high-latitude cold regions, we selected an “environmental precore” of 3,663 accessions using environmental data and compared the Donor opulation of Environments (DPE) in Asia and the Target Population of Environments (TPE) in Central Europe in the present and 2070. Using single nucleotide polymorphisms, we reduced the precore into two diverse core collections of 183 and 366 accessions to serve as diversity panels for evaluation in the TPE. Genetic differentiation between precore and non-precore accessions revealed genomic regions that control maturity, and novel candidate loci for environmental adaptation, demonstrating the potential of diversity panels for studying adaptation. Objective-driven core collections have the potential to increase germplasm utilization for abiotic adaptation by breeding for a rapidly changing climate, or de novo adaptation of crops to expand cultivation ranges. 相似文献
153.
154.
Background and Aims
Leaf hydraulic properties are strongly linked with transpiration and photosynthesis in many species. However, it is not known if gas exchange and hydraulics will have co-ordinated responses to climate change. The objective of this study was to investigate the responses of leaf hydraulic conductance (Kleaf) in Glycine max (soybean) to growth at elevated [CO2] and increased temperature compared with the responses of leaf gas exchange and leaf water status.Methods
Two controlled-environment growth chamber experiments were conducted with soybean to measure Kleaf, stomatal conductance (gs) and photosynthesis (A) during growth at elevated [CO2] and temperature relative to ambient levels. These results were validated with field experiments on soybean grown under free-air elevated [CO2] (FACE) and canopy warming.Key results
In chamber studies, Kleaf did not acclimate to growth at elevated [CO2], even though stomatal conductance decreased and photosynthesis increased. Growth at elevated temperature also did not affect Kleaf, although gs and A showed significant but inconsistent decreases. The lack of response of Kleaf to growth at increased [CO2] and temperature in chamber-grown plants was confirmed with field-grown soybean at a FACE facility.Conclusions
Leaf hydraulic and leaf gas exchange responses to these two climate change factors were not strongly linked in soybean, although gs responded to [CO2] and increased temperature as previously reported. This differential behaviour could lead to an imbalance between hydraulic supply and transpiration demand under extreme environmental conditions likely to become more common as global climate continues to change. 相似文献155.
156.
《Critical reviews in biotechnology》2013,33(4):349-362
Soybean (Glycine max) is one of the most important crops in legume family. Soybean and soybean-based products are also considered as popular food for human and animal husbandry. With its high oil content, soybean has become a potential resource for the production of renewable fuel. However, soybean is considered one of the most drought-sensitive crops, with approximately 40% reduction of the yield in the worst years. Recent research progresses in elucidation of biochemical, morphological and physiological responses as well as molecular mechanisms of plant adaptation to drought stress in model plants have provided a solid foundation for translational genomics of soybean toward drought tolerance. In this review, we will summarize the recent advances in development of drought-tolerant soybean cultivars by gene transfer. 相似文献
157.
Effect of Soybean Monoculture on the Bacterial Communities Associated with Cysts of Heterodera glycines 总被引:1,自引:0,他引:1
Yingbo Zhu Fengyu Shi Jianqing Tian Jianbin Liu Senyu Chen Meichun Xiang Xingzhong Liu 《Journal of nematology》2013,45(3):228-235
The soybean cyst nematode (SCN), Heterodera glycines, can cause significant reductions in soybean yield and quality in many parts of the world. Natural biological control may play an important role in regulating SCN population. In this study the bacterial communities associated with SCN cysts obtained from fields under different lengths of soybean monoculture were explored. Soil samples were collected in 2010 and 2011 from six fields that had been used for soybean monoculture for 2 to 41 yr. SCN population densities were determined and bacterial communities from SCN cysts were investigated by Biolog and PCR-DGGE methods. SCN population densities initially increased in the first 5 yr of soybean monoculture but then declined steeply as years of soybean monoculture increased. Catabolic diversity of bacterial communities associated with cysts tended to decline as number of years of monoculture increased. Some specific PCR-DGGE bands, mainly representing Streptomyces and Rhizobium, were obtained from the cysts collected from the long-term monoculture fields. Principal component analysis of Biolog and PCR-DGGE data revealed that bacterial communities associated with cysts could be divided into two groups: those from cysts obtained from shorter (< 8 yr) vs. longer (> 8 yr) monoculture. This research demonstrates that the composition of the bacterial communities obtained from SCN cysts changes with length of soybean monoculture; the suppressive impact of these bacterial communities to SCN is yet to be determined. 相似文献
158.
通过顶置光源植物生长室控制380和760 μmol·mol-1 2个CO2浓度水平,研究了磷缺乏与正常供磷条件下,CO2浓度升高对玉米/大豆间作、玉米单作和大豆单作3种种植模式下作物株高、茎粗、叶面积及干物质积累的影响.结果表明:(1)CO2浓度升高能显著增加单/间作玉米、大豆的株高、茎粗、叶面积、根干重、地上部干重及总干重.(2)CO2浓度升高对供磷水平下单、间作玉米大豆的株高、茎粗、叶面积及干物质积累量增加的正效应均大于缺磷处理.(3)两种CO2浓度下,间作大豆与单作大豆生长差异不显著,而间作玉米较单作玉米有明显的生长优势,且供磷和CO2浓度的升高均能够促进这种优势. 相似文献
159.
以铝敏感型黑豆(简称SB)幼苗为实验材料,在水培条件下进行不同浓度过氧化氢(H2O2)和AlCl3处理,考察其生长和相关生理指标变化,探讨H2 O2预处理缓解黑豆铝毒害的生理以及分子机理.结果显示:(1)黑豆幼苗根的相对生长量在0.1和1.0 μmol·L-1 H2O2处理下始终得到显著促进,并以后者效果更好,而在10.0和100.0 μmol·L1 H2O2处理下先表现促进后受到显著抑制.(2)经过1.0 μmol·L-1 H2O2预处理的SB幼苗在不同程度Al3+胁迫(50~400 μmol·L 1)3周后,其叶片和根中总蛋白含量分别显著增加了16.7%~41.2%和10.0%~25.0%,MDA含量减少了近50%;而其同期的SOD和POD活性显著增加.(3) H2 O2预处理可诱导SB根和叶中的SOD基因(Mg/Fe-SOD和Mn-SOD)的表达水平明显提高.研究表明,低浓度H2O2能显著促进铝胁迫下铝敏感型黑豆幼苗生长,且主要是通过增加植株抗氧化酶活性和相关基因表达水平来提高其对铝胁迫的抗性. 相似文献
160.
《Bioscience, biotechnology, and biochemistry》2013,77(9):1980-1983
We have previously identified a potential bile acid-binding peptide sequence (VAWWMY) in acidic polypeptide A1a of the soybean glycinin A1aB1b subunit (Choi, S. K., et al., Biosci. Biotechnol. Biochem., 66, 2395–2401 (2002)). In this study, we introduced the nucleotide sequence encoding this peptide in the coding DNA which corresponds to amino acids between 251 and 256, and 282 and 287 into the A1a polypeptide by replacement to respectively give modified versions A1aM1 and A1aM2. A fluorescence analysis demonstrates that their bile acid-binding ability was improved compared to A1a. Moreover, modified proglycinin A1aB1b with the VAWWMY sequence at the same sites as those of A1aM1 and A1aM2 was judged to assume the correct conformation. These results suggest the possibility of developing transgenic crops to accumulate the modified glycinin. 相似文献