2011 Vol. 10 No. 7 Previous Issue    Next Issue

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    Original Articles
    Diversity, Structure, and Marker-Trait Association Analysis of the Maize Recombinant Inbred Line Population
    CHEN Jing-tang; HU Li-zong; ZHU Li-ying; GUO Jin-jie; ZHAO Yong-feng and HUANG Ya-qun
    2011, 10(7): 975-986.  DOI: 10.1016/S1671-2927(11)60084-9
    Abstract ( )   PDF in ScienceDirect  
    Association mapping has emerged as a new tool to elucidate complex quantitative trait loci in maize, but there are fewreports about systematic association analysis for the specific SSR markers with agronomic traits of interest in China.We investigated the morphological and genetic diversity and population structure for 76 maize recombinant inbredlines, and then association analysis were further performed between 48 simple sequence repeat loci and 17 morphologicaltraits, consisting of nine ear-related traits and eight other traits. The 48 SSR markers were screened out and furtherclassified into two groups including a group of loci in regions harboring reported quantitative trait loci that affect earshape and a group of markers distributing on the whole genome randomly. The result indicated that the population ofrecombinant inbred lines was structured, showing five subpopulations. Our association results revealed that therewere 82, 59, and 40 significant associations detected by K-test, logistic regression, and both analysis, respectively.When the 17 traits were considered separately, the significant associations between Q-SSRs and E-traits were raised to27.8%, whereas the other groups of combinations ranged between 2.3 and 6.3%. As the proportion of significantassociations is higher among the Q-SSR subset of markers and the subset of traits related to ear shape than those forall of the other combinations, we conclude that this approach is valid for establishing true positive marker-traitrelationships. Our results also demonstrated that association mapping could complement and enhance previous QTLinformation for marker-assisted selection.
    Mapping of QTL Associated with Drought Tolerance in a Semi-Automobile Rain Shelter in Maize (Zea mays L.)
    ZHU Jing-jing*, WANG Xiao-peng*, SUN Cui-xia, ZHU Xiu-miao, LI Meng, ZHANG Guo-dong, TIAN Yanchen, WANG Ze-li
    2011, 10(7): 987-996.  DOI: 10.1016/S1671-2927(11)60085-0
    Abstract ( )   PDF in ScienceDirect  
    Drought is a major constraint in maize production worldwide. We studied quantitative trait loci (QTL) underlying droughttolerance for maize plants grown in two different environments. Traits investigated included ASI, plant height, grain yield,ear height, and ear setting. A genetic linkage map was constructed with 120 simple sequence repeat (SSR) markers basedon an F2 population derived from a cross between D5 (resistant parent) and 7924 (susceptible parent). Correlation andheritability were calculated. QTLs of these traits were identified by composite interval mapping combined with a linkagemap covering 1 790.3 cM. The markers were arranged in ten linkage groups. QTL mapping was made of the mean traitperformance of the 180 F2:3 population. The results showed five, five, six, four, and five QTLs for ASI, plant height, grainyield, ear height, and ear setting under full irrigation condition, respectively, and four, seven, six, four, and four QTLs forASI, plant height, grain yield, ear height, and ear setting under severe late stress conditions, respectively. Especially thefour QTLs detected for five traits in 2008 and 2009. The universal QTLs information generated in this study will aid inundertaking an integrated breeding strategy for further genetic studies in drought tolerance improvement in maize.
    Relationship Among Yield Components and Selection Criteria for Yield Improvement in Early Rapeseed (Brassica napus L.)
    LU Guang-yuan, ZHANG Fang, ZHENG Pu-ying, CHENG Yong, LIU Feng-lan, FU Gui-ping, ZHANG , Xue-kun
    2011, 10(7): 997-1003.  DOI: 10.1016/S1671-2927(11)60086-2
    Abstract ( )   PDF in ScienceDirect  
    The objective of this study was to determine the relationship between seed yield and other important agronomic traits ofearly-maturing rapeseed as a rotation crop in a double-cropping rice area using Pearson’s correlation coefficient as well asto estimate direct and indirect effects of specific yield component traits on seed yield via path analysis. Nineteen rapeseedgenotypes were grown at ten environments in South China during 2008-2009 and 12 characters were evaluated. Analysisof variance showed that environment had a significant impact on all characters. For most characters the genotype byenvironment interaction was weak and not statistically significant. Simple correlation analysis indicated that the numberof primary branches (PB), number of pods on the main raceme (PR), and number of seeds per pod made significantcontributions to seed yield per plant (SYP), while 1 000-seed weight was negatively correlated with SYP (r=-0.485, P<0.05).Furthermore, number of pods per plant (PP), PB, and PR had the greatest direct effects on SYP. In addition, PP and PB werethe best indicators to predict seed yield in stepwise regression analysis. Finally, yield component differences betweenearly- and medium-maturity varieties were compared; this showed that to improve the seed yield of early varieties, moreemphasis should be given to increase PP, PB, and PR, and reduce plant height and shortening of growth duration inbreeding practice.
    Construction of a Normalized Full-Length cDNA Library of Sesame Developing Seed by DSN and SMART
    KE Tao; DONG Cai-hua; MAO Han; ZHAO Ying-zhong; LIU Hong-yan and LIU Sheng-yi
    2011, 10(7): 1004-1009.  DOI: 10.1016/S1671-2927(11)60087-4
    Abstract ( )   PDF in ScienceDirect  
    Sesame (Sesamue indicum L.) is one of the most important oilseed crops with high oil yield. Here, we described a simpleand efficient method for constructing a normalized cDNA library from a high oil content cultivar of sesame Zhongzhi 14,during its oil accumulation stages. It combined switching mechanism at 5´-end of RNA transcript (SMART) technique andduplex-specific nuclease (DSN) normalization methods. Double-stranded cDNAs were synthesized from mRNAs, processedby normalization and Sfi I restriction endonuclease, and finally the cDNAs were ligated to pDNR-LIB vector. The ligationmixture was transformed into Escherichia coli DH10B by electroporation. The capacity of the library was 1.0×106 clonesin this library. Gel electrophoresis results indicated the fragments ranged from 700 to 2 000 bp, with the average size of1 800 bp. Random picking clones showed that the recombination rate was 100%. The results showed that the cDNA libraryconstructed successfully was a full-length library with high quality, and could be used to screen the genes related todevelopment of oil synthesis.
    Expression Analysis of Restorer Alleles-Induced Genes in Pepper
    GUO Shuang, MA Ning, YANG Wen-cai, SUN Yu-jie, SHEN Huo-lin
    2011, 10(7): 1010-1015.  DOI: 10.1016/S1671-2927(11)60088-6
    Abstract ( )   PDF in ScienceDirect  
    Fertility restoration of cytoplasmic male-sterility in pepper (Capsicum annuum L.) is useful for commercial production ofhybrid seeds. However, the mechanism of fertility restoration has not been determined. We previously constructed acDNA library and identified some genes related to fertility restoration in pepper using suppression subtractive hybridizationtechnology. In this study, the expression patterns of 20 genes were investigated using semi-quantitative RT-PCR. Threegenes expressed only in restorer lines, but not in sterility lines. Four genes expressed only in anther, but not in otherorgans. Among these 7 genes, the clone TG31 was observed to specifically express in anther of restorer lines. The workdescribed here provides a comprehensive overview on the expression pattern of the genes that are induced by restoreralleles in pepper. It will also contribute to the current understanding of molecular networks for the regulation of fertilityrestoration.
    Changes of Oxidative Stress and Soluble Sugar in Anthers Involve in Rice Pollen Abortion Under Drought Stress
    FU Guan-fu*, SONG Jian*, XIONG Jie, LI Yu-rong, CHEN Hui-zhe, LE Ming-kai and TAO Long-xing
    2011, 10(7): 1016-1025.  DOI: 10.1016/S1671-2927(11)60089-8
    Abstract ( )   PDF in ScienceDirect  
    Two rice maintaining lines with different drought tolerances, viz., Jin 23B (tolerant) and Zhenshan 97B (sensitive), wereused to study the oxidative stress and soluble sugar in rice anthers and pollen viability under drought stress duringflowering stage. Higher antioxidant enzyme activities and lower malonaldehyde (MDA) content in rice anthers wereobserved in Jin 23B than in Zhenshan 97B under drought stress. Further, a great increase in the content of soluble sugarin rice anthers of Jin 23B was observed across the whole drought exposure, while Zhenshan 97B showed significantdecrease in soluble sugar during 9-12 d after drought stress (DADS). Accordingly, a marked decline of pollen fertility andactivity, pollen numbers in an anther and pollen numbers on a stigma was observed in Zhenshan 97B, whereas littledifference was found in Jin 23B. Thus, we suggest that pollen abortion caused by drought stress may be related with thereciprocity between oxidative stress and soluble sugar content in rice anthers.
    Effect of Photoperiod on Key Enzyme Activities of Respiration in Nectarine Buds During Dormancy Induction
    LI Dong-mei, LI Ling, TAN Yue, CHEN Xiu-de, ZHANG Hai-sen, GAO Dong-sheng , LI Jin
    2011, 10(7): 1026-1031.  DOI: 10.1016/S1671-2927(11)60090-4
    Abstract ( )   PDF in ScienceDirect  
    Shuguang (Prunus persica var. nectariana cv. Shuguang) nectarine was used to study effects of photoperiod on keyenzymeactivities of respiration during dormancy induction. The dormancy status was determined with sprouting ability.Spectrophotometry was used to investigate activities of phosphohexose isomerase (PGI), malic dehydrogenase (MDH),and glucose-6-phosphate dehydrogenase (G6PDH). The results revealed that short day (SD) treatment promoted dormancyinduction while long day (LD) treatment postponed the process. During dormancy induction, PGI activities declined,MDH activities changed little, and G6PDH activities increased both in flower buds and leaf buds. PGI activities and MDHactivities in SD treatment were lower than control, and G6PDH activities were higher, which was opposite with LDtreatment. The changes of respiratory key-enzyme activities were adjusted by photoperiod and correlated with thedevelopment of dormancy induction.
    Characteristics of Endogenous Hormone Variations in the Roots of Alfalfa(Medicago sativa L.) Cultivars of Different Fall Dormancies During SpringRegrowth Stage
    HAN Qing-fang, MENG Hai-tao, JIA Zhi-kuan, XU Ling-fei, WU Feng-ping , DING Rui-xia
    2011, 10(7): 1032-1040.  DOI: 10.1016/S1671-2927(11)60091-6
    Abstract ( )   PDF in ScienceDirect  
    Regrowth traits of alfalfa (Medicago sativa L.) in spring are closely related to its fall dormancy before winter. In order todetermine the relationship between fall dormancy (FD) grade and hormone variation pattern and provide academic referencesfor the variety improvement and production of alfalfa, the variations of gibberellins (GA3), indole-3-acetic acid (IAA), andabscisic acid (ABA) in alfalfa roots during regrowth period in spring were examined by high performance liquidchromatography (HPLC). The study involved seven alfalfa cultivars that belonged to four fall dormant grades, i.e., 2, 4, 6,and 8. The results showed that the differences in spring regrowth among the alfalfa cultivars were partially associatedwith their root hormone levels. The alfalfa cultivars that belonged to the same dormancy grades presented similarvariation trends in endogenous hormone content in their roots during the spring regrowth stage. At the early regrowthstage, cultivars with a higher dormant grade had a higher GA3 concent and a lower ABA content in their roots than thecultivars with a lower dormant grade; and IAA content in roots of non- and semi-fall dormancy cultivars was higher thanthat of fall dormancy cultivars. During the whole period of spring regrowth, the root ABA content of fall dormancy alfalfacultivar is significantly higher than those of semi- and non-fall dormancy cultivars. GA3 contents in the roots of allcultivars under study showed a double-peak dynamic curve; root IAA contents of the studied cultivars presented adownward trend. But the trend did not significantly differed among the different fall dormant cultivars. The higher GA3content and lower ABA content in root of non-fall dormancy alfalfa lead to its earlier regrowth. Regrowth time and rate ofalfalfa can be regulated by exogenous GA3 or ABA at the early regrowth stage to meet producing requirement.
    Genetic Variation Among the Geographic Population of the Grain Aphid, Sitobion avenae (Hemiptera: Aphididae) in China Inferred from Mitochondrial COI Gene Sequence
    XU Zhao-huan, CHEN Ju-lian, CHENG Deng-fa, LIU Yong and Frédéric Francis
    2011, 10(7): 1041-1048.  DOI: 10.1016/S1671-2927(11)60092-8
    Abstract ( )   PDF in ScienceDirect  
    In order to characterize the genetic relationship of the geographic populations of Sitobion avenae (Hemiptera: Aphididae)in China, a 588 bp region of the mitochondrial cytochrome oxidase subunit I (mtDNA-COI) gene was sequenced andanalyzed among the different geographic populations. 269 individuals were collected from 17 localities in different wheatgrowingareas in China that covered most of the range reported for this species. Within the sequence among thesegeographic populations, 15 polymorphic sites defined 16 distinct haplotypes, ranging in sequence divergence from 0.2%(one nucleotide) to 1.7% (10 nucleotides). Of the 15 variable sites, 12 were transitional substitutions, 2 were transversionalsubstitutions and 1 was transitional and transversional substitution. Phylogenetic analysis showed that all haplotypeswere highly interconnected with each other, in absence of phylogeographic structing. Each of 8 haplotypes was foundonly at one locality, and the other haplotypes were the widespread distributed in the different localities. The highergenetic diversity was found in the northern China populations than that in the southern China populations. The lowgenetic differentiation (FST=-0.06945-0.69857) and high migration rate (Nm=0.21575-infinite) of Chinese populations suggestthat dispersal over long distance is a major factor in the demography of S. avenae.
    Occurrence of Glyphosate-Resistant Horseweed (Conyza canadensis) Population in China
    SONG Xiao-ling, WU Jia-jun, ZHANG Hong-jun and QIANG Sheng
    2011, 10(7): 1049-1055.  DOI: 10.1016/S1671-2927(11)60093-X
    Abstract ( )   PDF in ScienceDirect  
    Horseweed (Conyza canadensis), an invasive alien weed, is one of the main weeds in orchards in China. Althoughglyphosate has been used for control of horseweed and many other weeds in orchards for more than 25 years in China, acase of glyphosate-resistant horseweed has not been identified in orchard in China so far despite glyphosate-resistanthorseweed cases have been reported in some other countries. Seeds of 25 horseweed populations were collected fromdifferent orchards with different glyphosate application history. Potted seedlings with 11-13-leaf growth stage weretreated with glyphosate at 0.035, 0.07, 0.14, 0.28, 0.56, 1.12, 2.24, 4.48, and 8.96 kg a.i. ha-1. The dosage dependenceresponse curve of each population was constructed with Log-logistic dose response regression equations. The ED50value of each population was calculated and compared with the susceptible population from China. Different populationshad different relative glyphosate-resistant levels which increased with the number of years of glyphosate application.Two populations with the highest resistance levels, 8.28 and 7.95 times, were found in Ningbo, Zhejiang Province, China,where glyphosate was used for weed control in orchards twice each year for 15 yr. The two resistant populationsaccumulated approximately two to four times less shikimic acid than the two susceptible populations 48 h after glyphosateapplication.
    A Photosensitivity Insecticide, 5-Aminolevulinic Acid, Exerts EffectiveToxicity to Oxya chinensis (Orthoptera: Acridoidea)
    YANG Mei-ling; YIN Kun; GUO Ya-ping; MA En-bo and ZHANG Jian-zhen
    2011, 10(7): 1056-1063.  DOI: 10.1016/S1671-2927(11)60094-1
    Abstract ( )   PDF in ScienceDirect  
    5-Aminolevulinic acid (ALA), a major photosensitivity insecticide, has attracted increasing attention as a new type of highly efficient, environmental friendly pesticide to be used to control the pest. To examine whether or not ALA acts effectively to grasshopper, Oxya chinensis and elucidate the detoxification mechanism of ALA, the susceptibility to ALA was assessed in O. chinensis and two major metabolic detoxification enzymes including glutathione S-transferases (GSTs) and general esterases (ESTs)-specific activities were compared in different development stages and different body sections
    of O. chinensis treated by ALA and the control. The results showed that the ALA exhibited obvious toxicity to the grasshopper in different development stages. In the low-dose treatment (0.0597 mmol L-1), the mortalities of O. chinensis reached a significant level (55.5% in the 1st instar nymphs, 61.4% in the 2nd instar nymphs, 71.4% in the 3rd instar nymphs, and 64.4% in the 4th instar nymphs. But, there was no dose-dependent toxic effect. Thereby, we proposed that ALA has the potential for acting as photosensitivity insecticide for controlling O. chinensis. GSTs activity assays using CDNB and DCNB as substrates indicated that the thorax and abdomen of the different instar nymphs treated by ALA showed 1.52-5.56 fold significantly increased GSTs activities compared with the control. However, for the ESTs-specific activity assay, there was no significant difference between O. chinensis treated by ALA and the control within different instar nymphs, when α-NA, α-NB and β-NA were used as substrates. Therefore, GSTs-mediated metabolic detoxification
    as evidenced by significantly increased GSTs activities might contribute to protect against oxidative damage and oxidative
    stress by ALA in O. chinensis.
    Changes of Soil Microbiological Characteristics After Solidago canadensis L. Invasion
    LIAO Min, XIE Xiao-mei, PENG Ying, MA Ai-li
    2011, 10(7): 1064-1071.  DOI: 10.1016/S1671-2927(11)60095-3
    Abstract ( )   PDF in ScienceDirect  
    The relationship between Solidago canadensis L. invasion and soil microbial communities was studied across the invasivegradients varying from 0 to 40, 80, and 100% coverage of S. canadensis. The results showed both soil microbial biomassC (Cmic) and N (Nmic) increased as the coverage of S. canadensis increased. Soil microbial quotient Cmic/Corg (microbialbiomass C/organic C) tended to increase linearly with the coverage of S. canadensis. Soil basal respiration (BR) alsoshowed a similar trend. The soil respiratory quotient qCO2 decreased with S. canadensis invasion, and remained at quitea constantly low level in the invasive soils. Sole carbon source utilization profiles analyses indicated that S. canadensisinvasion tended to result in higher microbial functional diversity in the soil. Average utilization of specific substrateguilds was highest in the soil with S. canadensis monoculture. Principle component analysis of sole carbon sourceutilization profiles further indicated that microbial functional diversity in the soil with S. canadensis monoculture wasdistinctly separated from those soils in the native area and the ecotones. In conclusion, S. canadensis invasion improvedsoil microbial biomass, respiration and utilization of carbon sources, and decreased qCO2, thus created better soil conditions,which in turn were more conducive to the growth of S. canadensis.
    Proteomic Study on Two Bradyrhizobium japonicum Strains with Different Competitivenesses for Nodulation
    LI Jun, XIAO Wen-li, MA Ming-chao, GUAN Da-wei, JIANG Xin, CAO Feng-ming, SHEN Delong, CHEN Hui-jun , LI Li
    2011, 10(7): 1072-1079.  DOI: 10.1016/S1671-2927(11)60096-5
    Abstract ( )   PDF in ScienceDirect  
    Competitiveness for nodulation of Bradyrhizobium japonicum strains plays a key role in symbiotic nitrogen fixation. Inorder to reveal the difference in competitiveness, B. japonicum 4534 with high competitiveness and B. japonicum 4222with low competitiveness for nodulation were analyzed by proteomic technique. The results showed that differentialproteins were fewer when two strains were treated with just daidzein. Only 24 and 10 differential proteins were detectedwith an up-regulated rate of 58 and 40% in B. japonicum 4534 and B. japonicum 4222, respectively. However, moredifferential proteins were detected upon treatment with daidzein and mutual extracellular materials simultaneously. Therewere 78 differential proteins detected in B. japonicum 4534 with 43 being up-regulated and 35 being down-regulated.These differential proteins, such as metabolism-related proteins, transporters, transcription-related proteins, translationrelatedproteins, and flagellin, were found to be associated with nodulation process. 25 up-regulated and 22 down-regulatedproteins were detected in B. japonicum 4222. Some of these proteins were not related to nodulation. More differentialproteins associated with nodulation in B. japonicum 4534 may be the reason for its high competitiveness. The results canprovide a guide to the selection and inoculation of effective strains and are significant to biological nitrogen fixation.
    Microsatellite-Based Genetic Differentiation and Phylogeny of Sheep Breeds in Mongolia Sheep Group of China
    SUN Wei, CHANG Hong, Musa Hussein Hassan, LIAO Xin-jun, CHU Ming-xing , Kija James
    2011, 10(7): 1080-1087.  DOI: 10.1016/S1671-2927(11)60097-7
    Abstract ( )   PDF in ScienceDirect  
    In the present study we studied the genetic structure of five Chinese sheep populations of Hu sheep, Tong sheep, SmalltailedHan sheep, Tan sheep, and Wadi (WD) sheep using 15 microsatellite loci. The results showed that the FIT, FST, andFIS statistics computed for the complete dataset had the following values, 0.523±0.140, 0.363±0.131 and 0.263±0.092,respectively. All loci were significantly contributed to the genetic differentiation among population (P<0.001). There is norelationship between the scatter of pairwise FST geographical distance points as geographical distance increases betweenthe five populations. Membership probabilities and genetic structure of sheep populations were estimated when K=2, thepopulations were classified into Hu, Tong, Han and WD, and Tan sheep group. However, when K=3, the populations wereclassified into Hu and Tong, Han and WD, and Tan sheep group. The findings supported the previous literatures thatthese populations are originated on different time stages from the primogenitor population and communicated geneticallywith each other by natural and artificial selection in different ecological environment.
    The Effect of Glycyl-Glutamine Dipeptide Concentration on Enzyme Activity,Cell Proliferation and Apoptosis of Jejunal Tissues from Weaned Piglets
    WANG Hui, JIA Gang, CHEN Zheng-li, HUANG Lan, WU Cai-mei, WANG Kang-ning
    2011, 10(7): 1088-1095.  DOI: 10.1016/S1671-2927(11)60098-9
    Abstract ( )   PDF in ScienceDirect  
    An experiment was conducted in a singly factorial design to study the effect of glycyl-glutamine dipeptide on enzymeactivity, cell proliferation and apoptosis of jejunal tissues from weaned piglets at different glycyl-glutamine concentrationlevels of 2, 4, 10, 20, and 30 mmol L-1, respectively. The glutaminase activity, diamine oxidase (DAO) activity, cellpeoliferation, apoptosis, and perotein metabolism were measured by the tissue culture method in vitro using jejunaltissues. The immunohistochemical method was used to study the cell proliferation and apoptosis of jejunal tissues. Theresults showed that compared to the blank control, the percentage and MOD value of BrdU-positicve cells incubated withglycyl-glutamine dipeptide solution were significantly (P<0.05) increased. Accordingly, the percentage and MOD valueof caspase-3-positive cells from tissue incubated with glycyl-glutamine dipeptide were notably lower (P<0.05) than thatfrom the control treatment. The glycyl-glutamine dipeptide increased the glutaminase activity, DAO activity and proteincontent of jejunal tissues, as the dipeptide concentration was on the rise (P<0.05). These results indicated that glycylglutaminedipeptide affected the jejunum development and adaptation of weaned piglets, and the function might befulfilled by enhancing the glutamine-related enzyme activity, thereby increasing the consumption of glutamine, and thenimproving the jejunal cell proliferation and suppressing cell apoptosis. The effects of glycyl-glutamine dipeptide relied ina dose-dependent manner, and the maximum effect was achieved at 20-30 mmol L-1 glycyl-glutamine dipeptide.
    Immunoproteomic Assay of Antigenic Surface Proteins in Streptococcus equi ssp. zooepidemicus
    MAO Ying, FAN Hong-jie, ZHOU Yong-hua, LU Cheng-ping
    2011, 10(7): 1096-1105.  DOI: 10.1016/S1671-2927(11)60099-0
    Abstract ( )   PDF in ScienceDirect  
    Streptococcus equi ssp. zooepidemicus (S. zooepidemicus) is a zoonotic pathogen with worldwide distribution. Lackingsuitable vaccine and virulent maker is still bottleneck to control this infection. An immunoproteomic approach has beenused to screen the membrane-associated and cell wall-associated proteins of S. zooepidemicus isolate in China CY todiscover vaccine candidate antigens and therapeutic agents. Finally, 11 membrane-associated proteins, and 13 cell wallassociatedproteins were successfully identified. BLAST (www.sanger.ac.uk) results also indicated that nucleotidesequences of majority identified proteins shared high homology (>60%) with S. zooepidemicus, except for AC1-3, AC5,AC8, and AC13. Moreover, genes for 7 of the identified proteins were detected from CY; compared with ST171, 3 of them(AM1, AM8 and AC11) were only found in virulent strains (CY). All of the proteins identified in this study remain not tobe reported in S. zooepidemicus. Some of the proteins serve a vital role in the immune system and reproduction of hostspecies according to available data, while the functions of the rest were seldom researched.
    Metabolic Regulation of Mammary Gland Epithelial Cells of Dairy Cow by Galactopoietic Compound Isolated from Vaccariae segetalis
    TONG Hui-li, GAO Xue-jun, LI Qing-zhang, LIU Jie, LI Nan, WAN Zhong-ying
    2011, 10(7): 1106-1116.  DOI: 10.1016/S1671-2927(11)60100-4
    Abstract ( )   PDF in ScienceDirect  
    In previous experiment, we isolated a compound dibutyl phthalate (DBP) from Vaccaria segetalis which had galactopoieticfunction on mammary gland epithelial cells of dairy cow (DCMECs). In this experiment, we ascertained the metabolicregulation function of DBP on DCMECs. Many genes related to lactation including Stat5, AMPK, â-casein, Glut1, SREBP-1,PEPCK, and ACC were detected by real-time PCR. Furthermore, Stat5 and AMPK were detected by Western blot andimmunofluorescence co-localization, respectively. The results showed that DBP stimulates the expression of Stat5 andp-Stat5, thus activates Stat5 cell signal transduction pathway and stimulates â-casein synthesis. DBP also raises theactivities of Glut1 and AMPK to stimulate glucose uptake and glycometabolism and activates the expression of AMPKdownstream target genes PEPCK and ACC and expression of SREBP-1 to stimulate milk fat synthesis. In addition, theactivities of HK, G-6-PDH, ICDH, ATPase, and energy charges were stimulated by DBP to increase the energy metabolismlevel of DCMECs. The results showed DBP stimulates energy metabolism related to galactopoietic function in DCMECs.
    Safety Evaluation of Diacylglycerol Microemulsion in Rats/Mice
    HUANG Tao, CHEN Ying, SHOU Tian-xing, YANG Jing, LI Duo
    2011, 10(7): 1117-1124.  DOI: 10.1016/S1671-2927(11)60101-6
    Abstract ( )   PDF in ScienceDirect  
    The objective of the present study was to evaluate potential adverse effects of diacylglycerol microemulsion (DAGM) inrats/mice. Acute safety evaluation was carried out by giving intragastrically with 20 mL 25% DAG kg-1 body weight ofDAGM or water with two groups of mice. Chronic safety evaluation with 40 male and 40 female Sprague-Dawley rats wascarried out by setting a control group and 3 different dose groups (n=10 male+10 female) administered with DAGM with6.7, 10 and 20 mL kg-1 body weight per day. Relevant parameters of liver and kidney function and biochemistry weredetermined by standard methods at end point. Acute toxicity study revealed the maximum tolerated dose (MTD) ofDAGM was 20 mL kg-1 body weight in mice. No death was observed at the dose of 20 mL kg-1 body weight per day. Chronicsafety evaluation did not show significant changes on hematological, histopathologic, clinical, and biochemical testswhen administered at levels of 6.7, 10 and 20 mL kg-1 body weight per day to rats for 30 d. No significant body weightchanges were observed in different dosages in both male and female rats. Our results suggested that acute and chronicadverse effects were not observed in histology and clinical parameters in both mice and rats. The results suggested thatDAGM is safe at the experimental levels.
    Effects of Nitric Oxide on the Quality and Pectin Metabolism of Yali Pears During Cold Storage
    LIU Li-qin, DONG Yu, GUAN Jun-feng
    2011, 10(7): 1125-1133.  DOI: 10.1016/S1671-2927(11)60102-8
    Abstract ( )   PDF in ScienceDirect  
    The effect of fumigation with 10, 20, and 30 μL L-1 nitric oxide (NO) was investigated to study the effects of NO on thequality of Yali pears during cold storage. The ethylene production, composition of cell walls, and cell-wall-modifyingenzyme activities were measured on fruits which were fumigated with NO (20 μL L-1). The results showed that NO not onlyreduced the peak value of ethylene production rate, the soluble sugar, soluble solid content, maintained higher firmness,starch, and NO content, but also retarded the degradation of covalent soluble pectin, accumulation of ionic soluble pectinand water soluble pectin. Moreover, NO fumigation decreased the activities of polygalacturonase (PG) and â-galactosidase(â-Gal) and delayed the peak of PG activity of fruits. Therefore, it indicated that NO fumigation could delay the softeningand ripening of Yali pears.
    Evaluation of Lethal Effects of Chlorantraniliprole on Chilo suppressalis and Its Larval Parasitoid, Cotesia chilonis
    HUANG Jia; WU Shun-fan and YE Gong-yin
    2011, 10(7): 1134-1138.  DOI: 10.1016/S1671-2927(11)60103-X
    Abstract ( )   PDF in ScienceDirect  
    Chlorantraniliprole was introduced into China from 2008 as a novel insecticide to control the rice stem borer, Chilosuppressalis (Walker). Cotesia chilonis (Matsumura) is the major parasitoid of C. suppressalis. We collected sevenpopulations of C. suppressalis and two populations of C. chilonis in different locations in China in 2009 to investigate thelethal effects of chlorantraniliprole on them. The populations of C. suppressalis from different regions showed variousLD50 values ranging from 2.00 to 18.70 ng per larva. Chlorantraniliprole has negligible acute contact toxicity (LC50>500 mgL-1) to C. chilonis and its oral toxicity is also much lower than that of fipronil (>2 800-fold difference in LC50). The resultsindicated that chlorantraniliprole is a good alterative in rice integrated pest management (IPM) programs. The susceptibilitydata of C. suppressalis will be useful for monitoring resistance levels in future.