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151.
Effect of the application of selenium on selenium content of soybean and its products 总被引:3,自引:0,他引:3
Two experiments were conducted to study the effect of the application of selenium on the selenium content of soybean and its
products in two counties with selenium-deficient soil. Selenium-enriched soybean was produced by the application of sodium
selenite and Se-enriched fertilizer. The selenium contents of soybeans, soybean protein and okra were determined by hydride-generation
atomic fluorescence spectrometry. The results showed that the selenium contents of soybean, soybean protein, and okra were
significantly increased by the application of sodium selenite and selenium-enriched fertilizer. Foliar application of selenium
provided a higher efficiency for increasing the selenium content of soybean than soil application. Significant differences
were found in that soybean cultivars exhibited different accumulation of selenium. There was no remarkable difference in soybean
yield, soybean protein, and lipid between selenium and control. The selenium-enriched protein derived from selenium-enriched
soybean could be used as a functional ingredient and soybean okra as a selenium-enriched feed for animals for increasing selenium
intake. 相似文献
152.
Affixing the O to Rubisco: discovering the source of photorespiratory glycolate and its regulation 总被引:1,自引:0,他引:1
Ogren WL 《Photosynthesis research》2003,76(1-3):53-63
The source of glycolate in photorespiration and its control, a particularly active and controversial research topic in the
1970s, was resolved in large part by several discoveries and observations described here. George Bowes discovered that the
key carboxylation enzyme Rubisco (ribulosebisphosphate carboxylase/oxygenase) is competitively inhibited by O2 and that O2 substitutes for CO2 in the initial `dark' reaction of photosynthesis to yield glycolate-P, the substrate for photorespiration. William Laing
derived an equation from basic enzyme kinetics that describes the CO2, O2, and temperature dependence of photosynthesis, photorespiration, and the CO2 compensation point in C3 plants. Jerome Servaites established that photosynthesis cannot be increased by inhibiting the photorespiratory pathway prior
to the release of photorespiratory CO2, and Douglas Jordan discovered substantial natural variation in the Rubisco oxygenase/carboxylase ratio. A mutant Arabidopsis plant with defective glycolate-P phosphatase, isolated by Chris Somerville, definitively established the role of O2 and Rubisco in providing photorespiratory glycolate. Selection techniques to isolate photorespiration-deficient plants were
devised by Jack Widholm and by Somerville, but no plants with reduced photorespiration were found. Somerville's approach,
directed mutagenesis of Arabidopsis plants, was subsequently successful in the isolation of numerous other classes of mutants and revolutionized the science
of plant biology.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
153.
Hangsik?Moon David?F.?HildebrandEmail author 《In vitro cellular & developmental biology. Plant》2003,39(6):623-628
Summary Cermination of soybean [Glycine max (L.) Merrill] somatic embryos and conversion to whole plants are generally low. This study was conducted to investigate the
effects of proliferation, maturation, and desiccation methods on conversion of soybean somatic embryos to plants. Soybean
cv. Jack somatic embryos, proliferated on a solid medium containing 90.5 μM (20 mgl−1) 2.4-dichlorophenoxyacetic acid (2.4-D) (MSD20), showed a regeneration rate signficantly higher than those proliferated in
a liquid medium containing 45.25 μM (10mgl−1) 2,4-D (FN Lite). When a liquid medium without 2,4-D and B5 vitamins (FN Superlite) was used for maturation, the duration
of time necessary for embryo development could be shortened by more than a month compared to maturation on a standard solid
medium (MSM6AC). An air-drying method, in which somatic embryos were desiccated in an empty sealed Petri dish for 3–5d, gave
rise to the best germination efficiency among the four desiccation methods tested: fast, slow, air, and KCl methods. The final
percentage of moisture seems important since embyros over-dried by the fast and slow methods did not convert well into plants. 相似文献
154.
Composite and clinal distribution of Glycine soja in Japan revealed by RFLP analysis of mitochondrial DNA 总被引:4,自引:0,他引:4
A. Tozuka H. Fukushi T. Hirata M. Ohara A. Kanazawa T. Mikami J. Abe Y. Shimamoto 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(2):170-176
Wild soybean (Glycine soja Sieb. et Zucc.), regarded as the progenitor of cultivated soybean [G. max (L.) Merr.], is widely distributed in East Asia. We have collected 1097 G. soja plants from all over Japan and analyzed restriction fragment length polymorphisms (RFLPs) of mitochondrial DNA (mtDNA) in
them. Based on the RFLPs detected by gel-blot analysis, using coxII and atp6 as probes, the collected plants were divided into 18 groups. Five mtDNA types accounted for 94% of the plants examined. The
geographic distribution of mtDNA types revealed that, in many regions, wild soybeans grown in Japan consisted of a mixture
of plants with different types of mtDNA, occasionally even within sites. Some of the mtDNA types showed marked geographic
clines among the regions. Additionally, some wild soybeans possessed mtDNA types that were identical to those widely detected
in cultivated soybeans. Our results suggest that the analysis of mtDNA could resolve the maternal lineage among plants of
the genus Glycine subgenus Soja.
Received: 16 June 1997/Accepted: 5 August 1997 相似文献
155.
An unnamed fungus, designated ARF, that parasitizes eggs and sedentary stages of cyst nematodes is a potential biological control agent of Heterodera glycines. The objectives of this study were to determine whether ARF isolates differ in their ability to suppress nematode numbers in soil and to compare the efficacy of ARF in heat-treated and native soil. The effectiveness of 11 ARF isolates was compared by introducing homogenized mycelium into heat-treated soil. Soybean seedlings were transplanted into pots containing fungus-infested soil and inoculated with H. glycines. After 30 or 60 days, the number of nematodes and the percentage of parasitized eggs were determined. Three isolates (907, 908, and TN14), which were previously reported to be weak egg parasites in vitro, consistently suppressed nematode numbers by 50% to 100%. Of the isolates previously reported to be aggressive egg parasites, four (903, BG2, MS3, and TN12) reduced nematode numbers by 56% to 69% in at least one experimental trial, but the other four had no effect on nematode numbers. When the efficacy of isolate TN14 was tested in heat-treated and native soil, nematode suppression was greater in the heat-treated soil in only one of two trials. In both soil treatments, nematode numbers were reduced by more than 60%. We conclude that virulence toward nematode eggs in vitro is a poor indicator of effectiveness of an ARF isolate in soil, and that the presence of soil microbes may reduce, but does not completely inhibit, activity of isolate TN14. 相似文献
156.
Molecular markers for resistance to Heterodera glycines in advanced soybean germplasm 总被引:7,自引:0,他引:7
Heer J.A. Knap H.T. Mahalingam R. Shipe E.R. Arelli P.R. Matthews B.F. 《Molecular breeding : new strategies in plant improvement》1998,4(4):359-367
Germplasm line J87-233 is resistant to soybean cyst nematode (SCN) races 1, 2, 3, 5 and moderately resistant to race 14 with resistance derived from 3 primitive sources, Peking, PI 88788 and PI 90763. F2:3 progeny of J87-233 and SCN-susceptible Hutcheson cross were evaluated for response to SCN races 1, 2, 3, 5 and 14. Linkage groups (LG) A, B, F, G, J, M, N, S were tested with 215 genomic clones and 45 decamers for parental genotypes. QTL for race 1 and QTL for race 3 were detected on LG A2, the region of BLT65V and SCAR 548/5631100/1025,975. The cluster analysis of 12 soybean cultivars and 38 plant introductions confirmed association of SCAR1100/1025,975 with resistance to races 1 and 3, and suggested possible DNA rearrangements that might give rise to new resistance specificities in the region. The highly significant association of K69T marker with SCN race 1 resistance in conjunction with its location, 18.5 cM from the reported QTL, exemplifies the importance of the QTL locus on LG G and suggests expansion of the linkage map in the LG G-terminal region. Detected interaction between loci on LG A2 and LG G, and also with loci on LG F and LG M, may play a significant role in the genotype-specific response to SCN. Identification of two major regions on LG A2 and LG G for SCN resistance shows their applicability to advanced germplasm, however, transmission of molecular marker alleles indicates that applied markers are not yet reliable in revealing all possible recombination events in breeding for SCN resistance. 相似文献
157.
Soybean meal was fermented withAspergillus usamii to improve zinc availability through the degradation of phytic acid. Rats fed a diet containing fermented soybean meal showed
greater femoral zinc than did animals fed a diet containing regular soybean meal. Zinc solubility in the small intestine was
higher in the rats fed fermented soybean meal than in the rats fed regular soybean meal. These results suggested that fermentation
withAspergillus usamii improved zinc availability in dietary soybean meal, which was induced by the increase of zinc solubility in the small intestine.
Adding the same amount of phytate that was contained in the regular soybean mealbased diet did not affect the amount of zinc
present in rats fed a fermented soybean meal-based diet with sodium phytate. Phytase activity was found in fermented soybean
meal, and this activity may degrade added phytate in fermented soybean meal-based diet. 相似文献
158.
John G. Streeter 《Phytochemistry》1985,24(1):174-176
Ononitol (4-O-methyl-myo-inositol) was identified as a major carbohydrate in Pisum sativum nodules, comprising 25–34% of the total mono- plus disaccharides in nodules formed by two Rhizobium leguminosarum strains. Ononitol was purified from Glycine max nodules and was found to be a minor carbohydrate in these nodules. The distribution of ononitol in bacteroids and cytosol from soybean nodules suggests that it is not synthesized by bacteroids. 相似文献
159.
Abstract: Western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, larval damage in maize following soybean was observed in Croatia in 2003 along the edges and within soybean fields which bordered continuous maize fields in previous year. The explanation was that WCR adults moved from the continuous maize to the neighbouring soybean fields to lay eggs. This study was designed to measure how far WCR adults will enter into neighbouring fields to lay eggs. The WCR adult population was monitored in continuous maize fields in 2003 and 2005 by using Pherocon® AM non-baited yellow sticky traps in the middle and on the borders of the maize field and at different distances and directions into neighbouring fields planted by wheat and soybean. Larval presence and root damage ratings (Iowa State University 1–6 ) were recorded at different locations within the maize field in following years. Approximately, the same concentration of WCR adults was recorded along the edges of the maize fields as recorded in the centres of those fields. A significant number of WCR adults was recorded up to a distance of 50 m into neighbouring fields. Regression analysis showed medium negative correlation between distance from previous maize field and root damage in the following year. Findings indicate that WCR egg lying can reach approximately 20 m into fields neighbouring maize fields and that significant root damage caused by WCR larvae in first-year maize following soybean and wheat can happen up to a distance of 20 m into those fields. Most farmers's fields in Croatia are up to approximately 50 m wide. As an edge effect for WCR egg laying can reach approximately 20 m into fields neighbouring maize fields, our research results indicate that it is possible to see WCR larval damage in rotated fields without those WCR's being the variant form. 相似文献
160.
以萌发初期大豆弯曲的子叶节为靶点,利用草甘膦(Roundup)点施鉴定法,分析了221份大豆微核心种质的草甘膦耐受性及其与抗草甘膦转CP4-EPSPS基因大豆AG5601的差异,结果表明,草甘膦对不同大豆种质的抑制程度与点施的草甘膦浓度呈正相关,Roundup稀释浓度为1/1000、1/10000时,草甘膦对大豆生长几乎无影响;Roundup稀释浓度为1/10时,草甘膦显著抑制大豆生长,导致植株死亡;Roundup稀释浓度为1/100时,不同大豆种质对草甘膦耐受性差异显著,并鉴定出对草甘膦具有较好耐受性的种质10份。虽然大豆微核心种质对草甘膦的耐受程度远远低于AG5601,但不同大豆种质对草甘膦耐受性存在显著差异,这为利用转基因和杂交转育技术培育抗草甘膦转基因大豆的受体或轮回亲本的选择提供了理论依据。 相似文献