Authors:L. Zhang, X. Shu, X. Wang, H. Lu, Q. Shu, and D. Wu
Five giant embryo mutants, described as
MH-gel, MH-ge2, MH-ge3, MH-ge4
, which were derived from the same indica rice
. ‘Minghui 86’ and characterized by 2.0, 1.88, 2.08, 1.93 and 1.88 times enlarged embryo than that of wild type, were selected for the current study. The mutated giant embryos were controlled by a single recessive gene, and except mutated locus with
other four loci were allelic to each other and the previous reported locus
in japonica rice
. ‘Kinmaze’. No obvious differences in physicochemical properties such as apparent amylose content (AAC), alkali spreading value (ASV), gel consistency (GC), and starch paste viscosity were observed between giant embryo mutants and wild type. Significant increases in the contents of crude lipid (LC), crude protein (PC), Vitamin B1 (V
), Vitamin B2 (V
), Vitamin E (V
), essential amino acids such as Arginine (Arg), Aspartic acid (Asp), Glutamic acid (Glu), Lysine (Lys), Methionine (Met), and mineral elements such as calcium (Ca), iron (Fe), potassium (K), phosphorus (P) and zinc (Zn) were detected in brown rice (BR) of giant embryo mutants. The amounts of gamma aminobutyric acid (GABA), an inhibitory neurotransmitter, were similar in the BR of giant embryo mutants and wild type, and more GABA content was observed in germinated brown rice (GBR) than BR. Significant enrichments were detected in the GBR of giant embryo mutants, basically corresponding to the enlarged embryo.
Authors:H. Bu, X. Chen, Y. Wang, X. Xu, K. Liu, and G. Du
In this paper, 633 species (involving 10 classes, 48 families, 205 genera) collected from the alpine meadow on the eastern Qinghai-Tibet plateau were studied. We tested potential factors affecting variation in mean germination time (MGT), i.e., plant traits (adult longevity, dispersal mode and seed size) or phylogeny, to evaluate if these factors were independent or they had interaction. Nested ANOVA showed that taxonomic membership accounted for the majority of MGT variation (70%), and in the generalized linear model, family membership could explain independently the largest proportion of MGT variation (29%). The strong taxonomic effect suggests that MGT variation within taxonomic membership is constrained. The other plant traits could also explain MGT variation independently (1% by adult longevity and dispersal mode, respectively, and 2% by seed size). Thus, the phylogeny was an important constraint to maintain the stability of species, and we could simplify the question if we regarded the phylogeny as an individual factor, but we could not negate the adaptive significance of the relationship between other plant traits and seed MGT. In addition, a large percentage of the variance remained unexplained by our model, thus important selective factors or parameters may have been left out of this analysis. We suggest that other possible correlates may exist between seed germination time and additional ecological factors (for example, altitude, habitat and post-dispersal predation) or phylogenetic related morphological and physiological seed attributes (e.g., endosperm mass) that were not evaluated in this study.
Authors:D. Xu, Q. L. Ning, X. Zhou, C. L. Chen, X. L. Tan, A. D. Wu, and X. Wang
Effects of ionic strength and of fulvic acid on the sorption of Eu(III) on alumina were investigated by using a batch technique.
The experiments were carried out at T=25±1 °C, pH 4-6 and in the presence of 1M NaCl. The results indicate that sorption isotherms of Eu(III) are linear at low
pH values. The sorption-desorption of Eu(III) on alumina at pH 4.4 is reversible, but a sorption-desorption hysteresis is
found at pH 5.0. Fulvic acid has an obvious positive effect on the sorption of Eu(III) on alumina at low pH values. The migration
of Eu(III) in alumina was studied by using column experiments and 152+154Eu(III) radiotracer at pH 3.8. For column experiments, Eu(III) sorbed on alumina can be desorbed completely from the solid
surface at low pH values. The findings are relevant to the evaluation of lanthanide and actinide ions in the environment.
Authors:B. Zhou, S. Jiang, L. Zou, X. Wang, D. Wang, J. Liu, S. Shang, and D. Zhou
A new compound cyclohexyl-t-butyldimethylammonium tetraphenylborate, [C6H11N(CH3)2(C(CH3)3)]BPh4 has been prepared, and its decomposition mechanism was studied by TG. The IR spectra of the products of thermal decomposition were examined at every stage. Kinetic analysis for the first stage of thermal decomposition process was obtained by TG and DTG curves, and kinetic parameters were obtained from the analysis of the TG-DTG curves with integral and differential equations. The most probable kinetic function was suggested by comparison of kinetic parameters.
Authors:L. Liu, T. Zhao, X. M. Cheng, C. H. Wang, and Z. T. Wang
Harmaline and harmine accounted for more than 70% in composition in extracts of P. harmala. More attention, however, should be paid to the other alkaloids which would be favorable or unfavorable to the efficacy and safety of the products. It was necessary to determine these trace alkaloids in the extracts; thereafter, most of them have been characterized. Diglycoside vasicine, vasicine, vasicinone, harmalol, harmol, tetrahydroharmine, 8-hydroxy-harmine, ruine, harmaline, and harmine were separated and identified with reference substances and characteristic MS spectra in extracts by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) and high-performance liquid chromatography (HPLC). Three trace alkaloids, vasicine, harmalol, and harmol were determined using the developed chromatographic separation method subsequently. The average contents of vasicine, harmalol, and harmol in extracts of ten batches were 2.53 ± 0.73, 0.54 ± 0.19, and 0.077 ± 0.03%, respectively. The total content of the three alkaloids was 3.23 ± 0.90% (from 1.81 to 4.48%). For rough estimation of all the relative alkaloids except of harmaline and harmine, the average total areas of all peaks in extracts varied from 4.35 to 26.64% detected at 220, 254, 265, 280, and 380 nm, respectively. The results indicated that area normalization method was powerless for the quality evaluation for traditional herb medicine consisting of numerous compounds with highly differential features. It might be concluded that LC-MS or HPLC could be utilized as a qualitative and quantitative analytical method for quality control of the extracts from seeds of P. harmala L.
Authors:J. Wang, M. Wu, B. Bao, Zh. Li, Q. Wang, X. Zhang, and G. Ye
This paper reports the study of hydrogen and carbon monoxide produced by radiation degradation of N, N-dimethylhydroxylamine
(DMHA). The results show that when the concentration of DMHA is between 0.1M–0.5M and the dose is between 10–1000 kGy, the
volume fraction of hydrogen is very high and increases with the dose. The volume fraction of hydrogen is little dependent
on the concentration of DMHA at lower dose but increases with increasing concentration of DMHA at higher dose. The volume
fraction of carbon monoxide is very low.
Authors:C. Wang, L. Li, X. Zhang, Q. Gao, R. Wang, and D. An
Molecular markers are important tools that have been used to identify the short arm of rye chromosome 1R (1RS) which contains many useful genes introgressed into wheat background. Wheat expressed sequence tag (EST) sequences are valuable for developing molecular markers since ESTs are derived from gene transcripts and more likely to be conserved between wheat and its relative species. In the present study, 35 sequence-tagged site (STS) primers were designed based on EST sequences distributed on homology group 1 chromosomes of
and used to screen specific markers for chromosome 1RS of
. Two primer pairs different from the early studies, STS
, which amplified a 1680-bp and a 1750-bp fragment, and STS
, which produced a 850-bp fragment from rye genome, were proved to be specific to chromosome 1RS since the corresponding fragments were only amplified from 1R chromosome addition line and wheat-rye lines with chromosome 1RS, but not from wheat-rye 2R-7R chromosome addition lines and the other lines lacking chromosome 1RS. Eleven wheat-rye lines derived from ‘Xiaoyan 6’ and ‘German White’ were used to test the presence of specific markers for 1RS. The specific fragments of 1RS were amplified in 4 wheat-rye lines, but not in the other lines. The testing results using EST-STS markers of 1RS were consistent with those obtained from fluorescence
hybridization (FISH), suggesting that these markers specific to 1RS could be used in marker-assisted selection (MAS) for incorporating 1RS into wheat cultivars in breeding.
Authors:B. Feng, Z.B. Xu, X. Wang, F. Jiang, G.J. Zhao, C. Xiang, and T. Wang
High molecular weight (HMW) glutenin subunits are important seed storage proteins in wheat and its related species. Novel HMWglutenin subunits in Aegilops tauschii accession of TA2484 were detected and characterized. SDS-PAGE analysis revealed the y-type subunit from TA2484 displayed similar electrophoretic mobility compared to that of 1Dy12 subunit. However, the electrophoretic mobility of x-type subunit was faster than that of 1Dx2 subunit. The primary structure of the two cloned subunits from TA2484 was similar to that of the x- and y-type subunits reported before. However, the 148 residues of the x-type subunit, which contained the sequence element GHCPTSLQQ, in the middle of the repetitive domain was quite different from other x-type subunits. Moreover, the 68 residues in this region were identical to those of the y-type subunits from the same accession. Consequently, 1Dx2.3*t (x-type subunit of TA2484) contains an extra cystenin residue located at the repetitive domain, which is novel compared to the x-type subunits reported so far. Phylogenetic analysis indicated that two subunits from accession TA2484 were in the x- and y-type subunit cluster, but bootstrapping value of 100% gave high support for the spilt between two subunits (1Dx2.3*t and 1Dy12.3*t) and their alleles, respectively. A hypothesis on the genetic mechanism generating this novel sequence of 1Dx2.3*t subunit is suggested.
Authors:J. Ji, J. Wang, Q. Zheng, J. Li, Z. Wang, X. Zhang, and A. Zhang
The introgressed alien chromosome in BC
progeny of the cross between common wheat (
Agropyron elongatum (Host) (2n=7X=70)
(Popd.) Barkworth & D.R. Dewey] was determined by genomic
hybridization (GISH), fluorescence
hybridization (FISH), using genomic DNA from
as a probe in GISH and repeat sequence pAs1, pSc119.2 as probes in FISH, and molecular marker techniques. The results revealed that the line was a chromosome additional line in which a pair of the chromosomes added was composed of chromosome segment from E-genome of
and short arm of 5B of common wheat cultivar Gao 38 identified by E-genome-specific primers. Powdery mildew test showed the line was highly resistant to powdery mildew as its
parent and this indicated that the gene of resistant to powdery mildew might come from
and localized on E-genome.
Authors:Y. Wang, M. Xu, G. Yin, L. Tao, D. Wang, and X. Ye
Although significant progress has been made on
-mediated wheat transformation, the current methodologies use immature embryos as recipient tissues, a process which is labor intensive, time consuming and expensive. In this study, we have managed to develop an
-based transformation scheme using explants derived from mature embryos. Based on transient expression of
-glucuronidase (GUS) marker, mature embryo halves prepared from freshly imbibed seeds were generally most susceptible to
-mediated T-DNA transfer. According to the results of callus induction and shoot production, Yumai 66 and Lunxuan 208 showed higher selection and regeneration efficiency than Bobwhite. In line with this finding, fertile T
transgenic plants were most readily obtained for both spring and winter wheat when mature embryo halves were used for co-inoculation by
cells. The presence of the antibiotic selection marker (
, encoding neomycin phosphotransferase II) in the T
plants was revealed by both genomic PCR amplification and the enzyme-linked immunosorbent assay (ELISA). Additional analysis showed that the transgene was stably inherited from the two different generations and segregated normally among the T
progenies. Further development along this line will raise the efficiency of wheat transformation and increase the use of this approach in the molecular breeding of wheat crop.