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61.
Legumes, with their unique ability to fix atmospheric nitrogen, play a vital role in ensuring future food security and mitigating the effects of climate change because they use less fossil energy and produce less greenhouse gases compared with N-fertilized systems. Grain legumes are second only to cereal crops as a source of human and animal food, and they contribute approximately one third of the protein consumed by the human population. The productivity of seed crops, such as grain legumes, is dependent on flowering. Despite the genetic variation and importance of flowering in legume production, studies of the molecular pathways that control flowering in legumes are limited.Recent advances in genomics have revealed that legume flowering pathways are divergent from those of such model species as Arabidopsis thaliana. Here, we discuss the current understanding of flowering time regulation in legumes and highlight the unique and conserved features of floral evocation in legumes. 相似文献
62.
Effect of abscisic acid application on root isoflavonoid concentration and nodulation of wild-type and nodulation-mutant soybean plants 总被引:1,自引:0,他引:1
Isoflavonoids (daidzein, genistein, and coumestrol) are involved in induction of nod genes in Bradyrhizobium japonicum and may be involved in nodule development as well. Abscisic acid (ABA) may also impact nodulation since ABA is reportedly
involved in isoflavonoid synthesis. The current study was conducted to evaluate whether ABA plays a role in differential nodulation
of a hypernodulated soybean (Glycine max L. Merr.) mutant and the Williams parent. Exogenous ABA application resulted in a decrease in nodule number and weight in
both lines. Isoflavonoid concentrations were also markedly decreased in response to ABA application in both inoculated and
noninoculated soybean roots. The inoculation treatment itself resulted in a marked increase in isoflavonoid concentrations
of NOD1-3, regardless of ABA levels, while only slight increases occurred in Williams. The nodule numbers of both soybean
lines across several ABA concentration treatments were highly correlated with the concentration of all three isoflavonoids.
However, differences in internal levels of ABA between lines were not detected when grown in the absence of external ABA additions.
It is concluded that differential nodule expression between the wild type and the hypernodulated mutant is not likely due
to differential ABA synthesis. 相似文献
63.
转基因大豆是目前种植最广泛的转基因作物之一,其中具有耐除草剂特性的转基因大豆占比最高。公众对转基因食品一直争议不断,因此,其批准商业化种植前的食用安全性评价显得尤为重要。已有研究显示,转基因耐除草剂大豆已经商业化种植了二十多年,迄今为止还没有观察到任何不良反应。目前已经批准的转基因耐除草剂大豆均进行了严格的毒理学评价、过敏性评价和营养学评价,经过严格评价后上市的转基因大豆可以放心食用。综述了转基因耐除草剂大豆的主要类型,分析了可能存在的安全性问题,对转基因耐除草剂大豆的食用安全性评价方法进行了总结,以期为后续相关转基因食品安全性评价工作的开展提供借鉴。 相似文献
64.
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
65.
66.
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67.
68.
《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
69.
《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
70.
An exopolygalacturonase was partially purified from mycelial extracts of a strain of Acrocylindrium. The enzyme was most active at pH 4.5 and showed a higher affinity for polygalac turo nic acid than for oligogalacturonic acids. The enzyme was found to hydrolyze glycosidic linkages at the non-reducing end of polygalacturonic acid molecules, giving only monogalacturonic acid as the reaction product. 相似文献