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    Cytological Behavior of Hybridization Barriers Between Oryza sativa and Oryza officinalis
    FU Xue-lin, LU Yong-gen, LIU Xiang-dong, LI Jin-quan , ZHAO Xing-juan
    2011, 10(10): 1489-1500.  DOI: 10.1016/S1671-2927(11)60143-0
    Abstract ( )   PDF in ScienceDirect  
    Oryza officinalis is one of the important wild species in the tertiary gene pool of Oryza sativa. It has a number of elite genes for rice breeding in resistance or tolerance. However, breeding barriers are so serious that the gene transfer is much difficult by sexual cross method between O. sativa and O. officinalis. Characteristics of the breeding barriers were systemically studied in this paper. When both the diploid (AA, 2n=2x=24) and autotetraploid (AAAA, 2n=4x=48) cultivated rice were crossed as maternal parents with O. officinalis (CC, 2n=2x=24), none F1 hybrid seeds were obtained. The young hybrid ovaries aborted at 13-16 d after pollinations (DAP). By rescuing hybrid embryos, in vitro F1 plantlets were obtained in 2x×2x combinations with the crossabilities lower than 0.5%. Lower rates of double-fertilization and abnormal development of hybrid embryo and endosperm were mainly observed in both combinations of 2x×2x and 4x×2x. Free endosperm nuclei in hybrid degenerated early at 1 DAP in a large scale. Almost no normal endosperm cells formed at 3 DAP. Development of a lot of embryos ceased at globular- or pear-shaped stage as well as some degenerated gradually. The hybrid plantlets were both male and female sterility. Due to the abnormal development, a diversity of abnormal embryo sacs formed in hybrids, and hybrid pollen grains were typically abortive. It showed that conflicts of genome A and C in hybrid induced abnormal meioses of meiocytes.
    Mapping of Mutant Gene prbs Controlling Poly-Row-and-Branched Spike in Barley (Hordeum vulgare L.) 
    HUANG Bi-guang , WU Wei-ren
    2011, 10(10): 1501-1505.  DOI: 10.1016/S1671-2927(11)60144-2
    Abstract ( )   PDF in ScienceDirect  
    A row-type mutant of barley named poly-row-and-branched spike (prbs) was previously obtained from a two-rowed cultivar Pudamai-2 after treated by inflorescence soaking in maize total DNA solution. The mutant produces branched spikes with irregular multiple rows. Genetic analysis indicated that the mutant phenotype was caused by a recessive gene prbs, and the PRBS locus had a recessive epistatic effect on an independent locus (denoted as Vrsx) conferring the variation of two-rowed spike vs. six-rowed spike. This study aimed to map PRBS as well as Vrsx using simple sequence repeats (SSR) markers. We developed an F2 population from a cross between the prbs mutant and a six-rowed cultivar Putianwudu for the gene mapping. As the two target loci interacted to result in a segregation ratio of two-rowed type:sixrowed type:prbs=9:3:4 in the population, we adopted a special strategy to map the two loci. PRBS was mapped between SSR markers HvLTPPB and Bmag0508A on the short arm of chromosome 3H, with distances of 24.7 and 14.3 cM to the two markers, respectively. Vrsx was mapped between SSR markers Bmag0125 and Bmag0378 on chromosome 2H, with distances of 6.9 and 15.3 cM to the two markers, respectively. This suggests that Vrsx should be the known locus Vrs1, which predominantly controls row-type variation in barley cultivars, and PRBS is a new locus related to the row type of spikes in barley.
    Identification, Genetic Analysis and Mapping of Resistance to Phytophthora sojae of Pm28 in Soybean
    WU Xiao-ling, ZHANG Bao-qiang, SUN Shi, ZHAO Jin-ming, YANG Feng, GUO Na, GAI Jun-yi, XING Han
    2011, 10(10): 1506-1511.  DOI: 10.1016/S1671-2927(11)60145-4
    Abstract ( )   PDF in ScienceDirect  
    Phytophthora sojae Kanfman and Gerdemann (P. sojae) is one of the most prevalent pathogens and causes Phytophthora root rot, which limits soybean production worldwide. Development of resistant cultivars is a cost-effective approach to controlling this disease. In this study, 127 soybean germplasm were evaluated for their responses to Phytophthora sojae strain Pm28 using the hypocotyl inoculation technique, and 49 were found resistant to the strain. The hypocotyl of P1, P2, F1, and F2:3 of two crosses of Ludou 4 (resistant)×Youchu 4 (susceptible) and Cangdou 5 (resistant)×Williams (susceptible) were inoculated with Pm28, and were used to analyze the inheritance of resistance. The population derived from the cross of Ludou 4×Youchu 4 was used to map the resistance gene (designated as Rps9) to a linkage group. 932 pairs of SSR primers were used to detect polymorphism, and seven SSR markers were mapped near the resistance gene. The results showed that the resistance to Pm28 in Ludou 4 and Cangdou 5 was controlled by a single dominant gene Rps9, which was located on the molecular linkage group N between the SSR markers Satt631 (7.5 cM) and Sat_186 (4.3 cM).
    Specific Expression of a Novel Nodulin GmN479 Gene in the Infected Cells of Soybean (Glycine max) Nodules
    CHENG Xian-guo, WANG Li, WANG He, YU Guo-hong, BAI You-lu , LIU Meng-meng
    2011, 10(10): 1512-1524.  DOI: 10.1016/S1671-2927(11)60146-6
    Abstract ( )   PDF in ScienceDirect  
    A novel nodulin gene, GmN479 genomic clone composing of 3 630 nucleotides was isolated from mature soybean nodules using GmN479 cDNA as a probe by subtractive hybridization procedure. GmN479 encodes 170 amino acids with 2.09 kb nucleotides promoter region, and contains two important upstream promoter elements, one is a conserved cis-acting sequence motif 5´-AAAGAT-3´ controlling nodulin gene expression, and the other is typical CAAT boxes. GmN479 gene has a single zinc-finger C2H2 domain YSCAFCQRGFSNAQALLGGHMNIH and a conserved motif, QALGGHMN in the zinc-finger with a short leucine repeat in the LDLELRLGL motif closed to C-terminal. These two conserved motifs share respectively higher identity with those in the floral regulator SUPERMAN gene, indicating that GmN479 may function as a transcriptional regulator, and is a likely candidate for playing a role in nodule-morphogenesis. Blotting data showed that GmN479 is a single copy presenting in the genome of soybean nodule, and its expression profile is similar to that of Lba, but it is different from that of ENOD2. GUS staining showed that GmN479 promoter just functions in the infected cells of nodules, indicating that the GmN479 is one of the truly symbiotically induced host genes, and belongs to a late nodulin gene. The expression pattern of GmN479 gene seems to imply that it may be closely related to the development of the nodule. In a sense, it may be a useful marker for identifying the development of the infected cell system in the nodules of soybean.
    Analysis of Genetic Effects for Heterosis of Erucic Acid and Glucosinolate Contents in Rapeseed (Brassica napus L.)
    ZHANG Hai-zhen, SHI Chun-hai , WU Jian-guo
    2011, 10(10): 1525-1531.  DOI: 10.1016/S1671-2927(11)60147-8
    Abstract ( )   PDF in ScienceDirect  
    The embryo, cytoplasmic, and maternal heterosis for erucic acid content (EAC) and glucosinolate content (GLS) of rapeseed (Brassica napus L.) were studied by using the genetic models for quantitative traits of seeds in diploid crops. Eight parents were included in a diallel mating design in two years. It was found that the heterosis of EAC and GLS was simultaneously controlled by genetic main effects and genotype×environment (GE) interaction effects. The general heterosis of most crosses for EAC was significantly positive, while it was not for GLS. The general heterosis was more important for two quality traits of rapeseed because of the low GE interaction heterosis in both years, especially for GLS. Among different genetic systems, significant positive embryo general heterosis and the negative maternal general heterosis were found for EAC and GLS in most hybrid crosses. Some hybrids with significant negative interaction heterosis were detected for either of EAC or GLS. In general, maternal general and interaction heterosis was more important for reducing EAC and GLS of rapeseed.
    Analysis of SSRs Information in Capsicum spp. from EST Database
    HUANG Huan-huan, ZHANG Zhong-hua, ZHANG Zheng-hai, MAO Sheng-li, WANG Li-hao , ZHANG Bao-xi
    2011, 10(10): 1532-1536.  DOI: 10.1016/S1671-2927(11)60148-X
    Abstract ( )   PDF in ScienceDirect  
    SSR markers are useful in pepper linkage mapping and gene location. 446 SSR markers have been reported, but they are insufficient. It is costly to develop SSR markers from DNA library, whereas it seems much easy to find in EST sequences in the GenBank of pepper through internet. In this study, attempts have been made to develop SSR markers in the EST sequences by using bioinformatics. EST sequences were trimmed by ‘est-trimmer.pl’ software, while 116915 EST sequences were obtained without poly ‘A’ or poly ‘T’, ranged between 100 and 700 bp. Using ‘e-PCR’ and ‘del.pl’ softwares, SSR sequences were identified. 2 508 microsatellite loci (larger than 20 repeats) were established and 755 SSR primers were designed using SSR finder software and Primer 3 software. There were 498 (0.43%) mono-, 1 026 (0.89%) di-, 518 (0.45%) tri-, 245 (0.21%) tetra-, 114 (0.10%) penta-, and 107 (0.09%) hexa-nucleotide SSRs. The estimated frequency of SSRs was approximately 1/25.12 kb. According to the distribution of SSRs in pepper, the mean length of pepper SSRs was 22.68 bp and the adenine rich repeats such as A/T, AG, AT, AAG, AAAT, and AAAC were predominant in each type of SSRs (mono-, di-, tri-, tetra-, penta-, and hexa-), whereas the C/G, CG, CCG repeats were less abundant. 210 primers were tested in 8 pepper cultivars and the PCR result revealed the existence of polymorphism among 127 (60.48%) SSR primers within 8 pepper cultivars. It is confirmed that pepper EST database could be efficiently exploited for availability of SSR markers.
    Relationship Between Grain Yield and Yield Components in Super Hybrid Rice
    HUANG Min, ZOU Ying-bin, JIANG Peng, XIA Bing, Md Ibrahim , AO He-jun
    2011, 10(10): 1537-1544.  DOI: 10.1016/S1671-2927(11)60149-1
    Abstract ( )   PDF in ScienceDirect  
    Chinese super hybrid rice breeding project has developed many new varieties with great yield potential. It is controversial which yield component should be emphasized in super hybrid rice production. The present study was conducted to compare super hybrid rice with common hybrid and super inbred rice and analyze contributions of yield components to grain yield of super hybrid rice under experimental conditions, and evaluate relationships between grain yield and yield components of super hybrid rice in farmer’s paddy fields. Field experiments were done in Changsha, Guidong, and Nanxian, Hunan Province, China, from 2007 to 2009. Eight super hybrid varieties, one common hybrid variety, and one super inbred variety were grown in each location and year. Rice production investigation was undertaken in high-yielding (Guidong), moderate-yielding (Nanxian), and low-yielding (Ningxiang) regions of Hunan Province, China, in 2009. Grain yield and yield components were measured in both the field experiments and rice production investigation. Super hybrid rice varieties outyielded common hybrid and super inbred varieties across three locations and years. Yield potential has been increased by 11.4% in super hybrid rice varieties compared with common and super inbred varieties. The higher yield of super hybrid varieties was attributed to improvement in panicle size. Panicles per m2 had the highest positive contribution to grain yield with the exception under yield level of 10.0 to 12.0 t ha-1, and was positively related to grain yield in farmer’s field at all of the high-, moderate-, and low-yielding regions. Our study suggests that panicle per m2 ought to be emphasized in super hybrid rice production.
    Negative Effects of Oxytetracycline on Wheat (Triticum aestivum L.) Growth, Root Activity, Photosynthesis, and Chlorophyll Contents  
    LI Zhao-jun, XIE Xiao-yu, ZHANG Shu-qing , LIANG Yong-chao
    2011, 10(10): 1545-1553.  DOI: 10.1016/S1671-2927(11)60150-8
    Abstract ( )   PDF in ScienceDirect  
    A solution culture experiment was performed to investigate the effects of oxytetracycline (OTC) on wheat (Triticum aestivum L.) growth, chlorophyll contents, and photosynthesis at five levels of 0, 10, 20, 40, and 80 mmol L-1 OTC. OTC is toxic to wheat. The wheat growth, especially wheat root was significantly decreased. Further OTC also significantly decreased root activity, chlorophyll contents, and photosynthetic parameters except for intercellular CO2 concentrations. The different responses of indicators such as root number, root activity and so on to OTC were also observed. The IC50 values for the tested indicators to OTC ranged from 7.1 to 113.4 mmol L-1 OTC. The order of indicator sensitivity to OTC was root number > stomatal conductance > chlorophyll a > total chlorophyll > photosynthetic rates > total surface area > transpiration rate > chlorophyll b > fresh weight of root > dry weight of root > total length > dry weight of shoot = fresh weight of shoot > total volume. The root number was more sensitive than other indicators with the IC50 value of 7.1 mmol L-1 OTC, and could be taken as the sensitive indicator to predict the hazards of OTC to wheat.
    Effect of Plant Density on Wild Oat Competition with Competitive and Non- Competitive Wheat Cultivars
    Mohammad Armin , Mohammed Asghripour
    2011, 10(10): 1554-1561.  DOI: 10.1016/S1671-2927(11)60151-X
    Abstract ( )   PDF in ScienceDirect  
    Wild oat (Avena ludoviciana) is one of the worst weeds in wheat fields. The effect of wheat density on wild oat competition with more or less competitive wheat cultivars (Triticum aestivum) was investigated at the Experimental Farm of Plant Pests and Diseases Research Institute, Karaj, Iran. The experiment was established as a factorial combination of wheat varieties Roshan as non-competitive and Niknejad as competitive; three wheat densities (recommended density, recommended+25%, and recommended+50%, corresponding respectively with 300, 375, and 450 plants m-2 for Roshan and 400, 500, and 600 plants m-2 for Niknejad) and four wild oat densities (0, 25, 50, and 75 plants m-2) were selected for this experiment. Hyperbolic equations were used to describe relationship between yield and weed density. Increase in wheat density reduced wild oat biomass. Maximum wild oat biomass was achieved at the highest density of the wild oat together with the lowest wheat density. The results showed that higher densities of wheat are able to suppress wild oat dry matter production. Inter-specific competition in Niknejad was 1.7 times more than that in Roshan. Maximum yields of Niknejad and Roshan in the presence of wild oat were obtained at recommended density+25% and recommended density, respectively. Increase in wheat density leads to a decrease in wheat yield due to an increase in intra-specific competition. Increase in wild oat density results in the reduction of wheat yield through decrease in fertile tiller per plant and spike m-2.
    Infection Behaviour of Melampsora larici-populina on the Leaf Surface of Populus purdomii  
    YU Zhong-dong, PENG Shao-bing, REN Zheng-zheng, WANG Dong-mei , CAO Zhi-min
    2011, 10(10): 1562-1569.  DOI: 10.1016/S1671-2927(11)60152-1
    Abstract ( )   PDF in ScienceDirect  
    Behaviours of urediospore germtube in Melampsora larici-populina on the leaf surface of Populus purdomii were studied by light microscope, scanning electron microscope (SEM), transmission electron microscope (TEM), and fluorescence microscope. Crab-like fusion cells on leaf surface, intercellular hyphal cells in leaf tissues, as well as nucleus states, were observed and counted up in this study. Under unsaturated humidity, 32% of germinated tubes fused into a distinguishable swollen crab-shaped cell at the merging site, and 10.5% of observed crab-like cells had more than three nuclei. Wedge-shaped mycelia developed and then penetrated the leaf surface directly, or indirectly through stomata. Tips of germtube passed through the intercellular cells of poplar leaves directly were found in TEM. Aniline blue dyeing also showed that the infecting hyphae could invade into the cuticle and epidemic cell wall directly. For the case of infection through stomata, there were two different situations. Short branches and wedge hyphae usually penetrated the leaf surface via opened stomata, whereas, some germtube branches and wedge hyphae penetrated leaves through the guard cell walls or stoma lips. In the latter case, the stomata were always closed. The samples from wild forestlands had the same fused cells and wedge hyphae, but the occurrence rate was much higher than that in the chamber. Even under the saturated air humidity, germtubes could roll back and formed fusion structure, or merged together with their tips. The fusion cells might centralize the plasma of merged germtubes and have a strong survival capacity to protect germtubes from dying under arid circumstances, and provide a chance of genetic variation as well.
    Expression and Characterization of a Sigma-Class Glutathione S-transferase of the Oriental Migratory Locust, Locusta migratoria manilensis (Meyen) 
    JIA Miao, QIN Guo-hua, LIU Ting, ZHANG Jian-zhen, ZHANG Xue-yao, ZHU Kun-yan, GUO Yaping, MA En-bo
    2011, 10(10): 1570-1576.  DOI: 10.1016/S1671-2927(11)60153-3
    Abstract ( )   PDF in ScienceDirect  
    A cDNA encoding a sigma-class glutathione S-transferase of the locust, Locusta migratoria manilensis (LmGSTs1), was cloned by reverse transcriptase-polymerase chain reaction. The 830 bp-long cDNA encoded a 615 bp open reading frame (204 amino acid polypeptide), which exhibited the structural motif and domain organization characteristic of GST sigmaclass. It revealed 59, 57, 57, and 56% identities to sigma-class GSTs from Blattella germanica, Gryllotalpa orientalis, Nasonia vitripennis, and Pediculus humanus corporis, respectively. A recombinant protein (LmGSTs1) was functionally expressed in Escherichia coli cells in a soluble form and purified to homogeneity. LmGSTs1 was able to catalyze the biotranslation of glutathione with 1-chloro-2,4-dinitrobenzene, a model substrate for GSTs, as well as with p-nitro-benzyl chloride. Its optimal activity was observed at pH 8.0 and at 30°C. Incubation for 30 min at temperatures below 50°C scarcely affected the activity. The I50 of reactive blue (RB) was 18.5 μmol L-1. In the presence of 0.05 mmol L-1 ethacrynic acid (ECA), LmGSTs1 showed (81±3)% of the original activities.
    Physiological Responses of Two Wheat Cultivars to Nitrogen Starvation
    WANG Xiao-li, SHAN Yu-hua, WANG Su-hua, DU Yan , FENG Ke
    2011, 10(10): 1577-1585.  DOI: 10.1016/S1671-2927(11)60154-5
    Abstract ( )   PDF in ScienceDirect  
    Plants need to be efficient in nutrient management, especially when they face the temporal nutrient defficiencies. Understanding how crops respond to nitrogen (N) starvation would help in the selection of crop cultivars more tolerant to N deficiency. In the present work, the physiological responses of two wheat cultivars, Yannong 19 (YN) and Qinmai 11 (QM), to N starvation conditions were investigated. The two cultivars differed in biomass and N rearrangement between shoots and roots during N starvation. QM allocated more N to roots and exhibited higher root/shoot biomass ratio than YN. However, tissue measurement indicated that both cultivars had similar nitrate content in leaves and roots and similar remobilization rate in roots. Microelectrode measurement showed that vacuolar nitrate activity (concentration) in roots of QM was lower than that in roots of YN, especially in epidermal cells. Nitrate remobilization rates from root vacuoles of two cultivars were also identical. Moreover, vacuolar nitrate remobilization rate was proportional to vacuolar nitrate activity. During N starvation, nitrate reductase activity (NRA) was decreased but there were no significant differences between the two cultivars. Nitrate efflux from roots reduced after external N removal and QM seemed to have higher nitrate efflux rate.
    Screening of a Composite Microbial System and Its Characteristics of Wheat Straw Degradation
    LI Pei-pei, WANG Xiao-juan, YUAN Xu-feng, WANG Xiao-fen, CAO Yan-zuan , CUI Zong-jun
    2011, 10(10): 1586-1594.  DOI: 10.1016/S1671-2927(11)60155-7
    Abstract ( )   PDF in ScienceDirect  
    To accelerate the decomposition of wheat straw directly returned to soil, we constructed a microbial system (ADS-3) from agricultural soil containing rotting straw residues using a 40-wk limited cultivation. To assess its potential use for accelerating straw decomposing, the decomposing characteristics and the microbial composition of ADS-3 were analyzed. The results indicated that it could degrade wheat straw and filter paper by 63.8 and 80%, respectively, during 15 d of incubation. Straw hemicellulose degraded dramatically 51.2% during the first 3 d, decreasing up to 73.7% by the end of incubation. Cellulose showed sustained degradation reaching 53.3% in 15 d. Peak values of xylanase and cellulase activities appeared at 3 and 11 d, with 1.32 and 0.15 U mL-1, respectively. Estimated pH averaged 6.4-7.6 during the degradation process, which approximated acidity and alkalinity of normal soils. The microbial composition of ADS-3 was stable based on denaturing gradient gel electrophoresis (DGGE) analysis. By using bacterial 16S rRNA and fungal 26S rRNA gene clone library analysis, 20 bacterial clones and 7 fungal clones were detected. Closest identified relatives of bacteria represented by Bacillus fusiformis, Cytophaga sp., uncultured Clostridiales bacterium, Ruminobacillus xylanolyticum, Clostridium hydroxybenzoicum, and uncultured proteobacterium and the fungi were mainly identified as related to Pichia sp. and uncultured fungus.
    Assimilation of Remote Sensing and Crop Model for LAI Estimation Based on Ensemble Kalman Filter
    LI Rui, LI Cun-jun, DONG Ying-ying, LIU Feng, WANG Ji-hua, YANG Xiao-dong , PAN Yu-chun
    2011, 10(10): 1595-1602.  DOI: 10.1016/S1671-2927(11)60156-9
    Abstract ( )   PDF in ScienceDirect  
    Data assimilation in agricultural remote sensing research is of great significance to integrate with remote sensing observations and model simulations for parameters estimation. The present investigation not only designed and realized the Ensemble Kalman Filtering algorithm (EnKF) assimilation by combing the crop growth model (CERES-Wheat) with remote sensing data, but also optimized and updated the key parameters (LAI) of winter wheat by using remote sensing data. Results showed that the assimilation LAI and the observation ones agreed with each other, and the R2 reached 0.8315. So assimilation remote sensing and crop model could provide reference data for the agricultural production.
    Transgenic Pigs Carrying a Synthesized Fatty Acid Desaturase Gene Yield High Level of ω-3 PUFAs
    REN Hong-yan, ZHENG Xin-min, CHEN Hong-xing , LI Kui
    2011, 10(10): 1603-1608.  DOI: 10.1016/S1671-2927(11)60157-0
    Abstract ( )   PDF in ScienceDirect  
    Polyunsaturated fatty acids (PUFAs) are essential for normal growth in mammals, especially the ω-3 PUFAs, which play important roles in preventing several life-threatening diseases, such as coronary heart disease and diabetes. In this study, we aimed to investigate whether the sFat-1 gene from Caenorhabditis briggsae could be functionally expressed in transgenic pigs, and whether the transgenic could synthesize high quality ω-3 PUFAs endogenously. In this study, a gene construct consisting of CMV promoter and 1.9 kb cDNA of ω-3 fatty acid desaturase gene (sFat-1) from C. briggsae was injected into the male pronucleus of pig embryos by microinjection. The piglets were screened for the transgene by PCR, Southern blot and reverse transcription-PCR analysis. Pigs that give positive results were mated with wild-type pigs to produce the next generation and the transmission of transgene was examined by PCR analysis. Fatty acids compositions of various tissues in the transgenic pigs were then analyzed by gas chromatograph. A total of 878 embryos were transferred into 42 recipients, among which 29 successfully got pregnant and gave birth to a total of 162 piglets, and 8 of them were identified to be transgenic. Fatty acid compositions in the transgenic pigs were altered, and the levels of ω-6: ω-3 ratios were decreased from 14.53 in the control to 2.62 in Fat-1 transgenic pigs. A number of primary sFat-1-transgenic pigs were bred in this study, which lays the foundation for cultivation of new varieties of transgenic pigs.
    DNA Polymorphisms of 5´-Flanking Region of Insulin-Like Growth Factor 1 Gene and Their Association with Reproduction Traits in Goats 
    WANG Ping-qing, TAN Ying, ZHANG Bao-yun, CHU Ming-xing, DENG La-mei, FAN Qi , LIUChong-xu
    2011, 10(10): 1609-1617.  DOI: 10.1016/S1671-2927(11)60158-2
    Abstract ( )   PDF in ScienceDirect  
    Research on the identity of genes and their relationship with traits of economic importance in farm animals could assist in the selection of livestock. In this study, the polymorphisms of insulin-like growth factor 1 (IGF1) gene in 561 goats of ten breeds were detected by polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) and their association with litter size and birth weight in three breeds were investigated. The effects of IGF1 polymorphisms on the breeding value for litter size and birth weight were examined using least square methods. Two deletions (CA) were detected in the microsatellite and two mutations (A1637G, T1640C) were found in 5´-flanking regulatory region. No significant association between the polymorphisms in 5´-flanking region of IGF1 and birth weight was found in the three breeds of goats. In Gulin Ma goats, two polymorphisms were found to affect litter size traits. In Chuandong White goats and Guizhou White goats, no significant difference (P<0.05) in litter size between goats carrying different genotypes was observed. Further evaluation and confirmation studies in more goat populations with larger sample sizes are necessary.
    Studies on Wool-Eating Ailment in Guizhou Semi-Fine Wool Sheep
    SHEN Xiao-yun
    2011, 10(10): 1618-1623.  DOI: 10.1016/S1671-2927(11)60159-4
    Abstract ( )   PDF in ScienceDirect  
    The clinical symptoms of a disorder which is known locally as “wool-eating ailment” in Guizhou semi-fine wool sheep in the Weining County of Guizhou Province, China, are poor weight gain, lost appetite, pica, emaciation, and wool-eating. The mineral composition of forage, and samples of blood, liver and wool from Guizhou semi-fine wool sheep in affected ranches were compared with those from the unaffected areas. The mean concentration of iron in forage from affected pasture was significantly higher than that from the unaffected pasture. The mean concentration of sulfur in forage from the affected and unaffected pasture was similar and within normal ranges. The mean concentration of sulfur in blood, liver and wool from the affected Guizhou semi-fine wool sheep was significantly lower than that from the unaffected sheep while the content of iron in blood, liver and wool from the affected sheep was significantly higher than that from the unaffected sheep. Oral administration of calcium sulfate prevented and cured the disease. We concluded that the disease of Guizhou semi-fine wool sheep in the Weining County is due to S deficiency caused by the high Fe in forages.
    Development of a Multiplex PCR for Diagnosis of Staphylococcus aureus, Escherichia coli and Bacillus cereus from Cows with Endometritis
    SUNDong-bo , WURui , HEXian-jing , WANGShuang , LINYun-cheng , HANXu , WANGYue-qiang , GUOTing-ting , WUGuo-jun , YANGKe-li
    2011, 10(10): 1624-1629.  DOI: 10.1016/S1671-2927(11)60160-0
    Abstract ( )   PDF in ScienceDirect  
    Staphylococcus aureus, Escherichia coli and Bacillus cereus are the major agents of cow endometritis in dairy cows. A multiplex PCR (SEB-mPCR) was established based on the conserved genes of S. aureus, E. coli and B. cereus, and the detection limits were 103, 102 and 103 CFU mL-1, respectively. SEB-mPCR could not amplify genomic DNA of pathogenic bacteria of other common bovine diseases. A total of 309 vaginal discharge samples from cows with endometritis were tested by SEB-mPCR. Of the samples, 23.95% had the three kinds of bacteria detected, 17.15% had S. aureu and E. coli, 9.39% had E. coli and B. cereus, and 9.71% had S. aureus and B. cereus. The rates of infections with S. aureus, E. coli and B. cereus were 11.35, 16.18 and 9.06%, respectively. Therefore, SEB-mPCR has a potential as a diagnosis tool for endometritis in dairy cows.
    Studies of GnRH-A Active Immunization Effects on LH and FSH Secretion and Histostructure of the Ovary and Uterus in Rabbits 
    WEI Suo-cheng, GONG Zhuan-di , WEI Min
    2011, 10(10): 1630-1637.  DOI: 10.1016/S1671-2927(11)60161-2
    Abstract ( )   PDF in ScienceDirect  
    The objective of the study is to investigate the effects of active immunization against gonadotropin releasing hormone agonist (GnRH-A) on secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in the pituitary, and to observe the histological structures and development about ovaries and uteri in female rabbits. 24 female rabbits (Oryctolagus cuniculus) were divided randomly into 4 groups (n=6), namely, experimental group I (EG-I), experimental II (EG-II), experimental III (EG-III), and control group (CG). Rabbits were subcutaneously injected with 1.0 mL GnRH-A (alarelin) antigen respectively at concentrations of 100, 100 and 50 μg mL-1 respectively, in EG-I, EG-II and EG-III. Alarelin antigen was re-injected in EG-II and EG-III with the same dosage on 20 d. CG was a blank. The ovarian and uterine samples were collected aseptically at the end of the experiment of 70 d. The tissue slices were observed under light and electron microscopes. Serum concentrations of LH and FSH were measured with ELISA. The results showed that serum LH concentrations in EG-II and EG-III reached the peak levels on 50 and 40 d respectively, and LH level in EG-II exceeded other 3 groups on 50 d (P<0.05). FSH level in EG-II was higher than those in EG-I, CG (P<0.01) and EG-III (P<0.05) on 40 d. GnRHA could increase the number of primary follicles, enlarge the primary follicle vertical diameter (PFV) and primary follicle transverse diameter (PFT), and promote growth and maturation of follicles. The endometrial epithelium thickness (EET) and uterine wall thickness (UWT) in three EGs were less than that in CG (P<0.05). GnRH-A can increase the quantities of mitochondrial cristaes, cortex granules in cytoplasm, broaden and lengthen zona pellucidas and microvilli of oocytes. It also enlarged nuclei of ooxytes and mitochondria, thereby it promoted the development of oocytes. Re-injection of 100 μg alarelin antigen enhanced the secretion of LH and FSH. GnRH-A promoted the growth and maturation of ovaries and follicles, suppressed uterine development, and also influenced histostructure of ovaries and uteri in female rabbits.
    Inhibitory Effects of 1-MCP and DPA on Superficial Scald of Dangshansuli Pear
    HUI Wei, NIU Rui-xue, SONG Yao-qiang , LI De-ying
    2011, 10(10): 1638-1645.  DOI: 10.1016/S1671-2927(11)60162-4
    Abstract ( )   PDF in ScienceDirect  
    Dangshansuli pear is one of crisp pears and has a non-climacteric respiratory pattern. Dangshansuli pear fruits were treated with 1 000 or 2 000 μL L-1 diphenylamine (DPA) for 1 min, or with 0.5 μL L-1 1-methylcyclopropene (l-MCP) for 12 h before cold storage at (2±0.5)°C for up to 210 d. Incidences of superficial scald and related physiological indexes were investigated during storage. The results showed that superficial scald occurred in control fruit with a rate of over 90% after 210 d at cold storage plus 10 d at room temperature. Treatments with 1 000 and 2 000 μL L-1 DPA and 0.5 μL L-1 l-MCP inhibited the accumulation of α-farnesene, conjugated trienes, total phenolic contents, and malondialdehyde (MDA) during storage. The treatments also decreased leakage of cell membrane and the activity of polyphenol oxidase (PPO) in the peel. These results indicate that 1-MCP and DPA treatments inhibit and postpone the occurrence of superficial scald of Dangshansuli pears remarkably in cold storage and post-storage shelf life, respectively, while the mechanisms were different. The results above may provide a theoretical evidence for the agriculture production.
    Variability of Pesticide Residues in Vegetables from the Marketplaces in Jinan City
    SONG Yu-feng, LU Xiao, REN Feng-shan
    2011, 10(10): 1646-1652.  DOI: 10.1016/S1671-2927(11)60163-6
    Abstract ( )   PDF in ScienceDirect  
    In order to provide technological support for risk estimation of pesticide residues taken from vegetables, the residues of pesticide in vegetables in Jinan City, China, were investigated. Moreover, the variability of pesticide residues in vegetables was explored, and the variability factor was calculated. The level of pesticide residue was studied by statistical method. The variability factor was calculated using the Harrell-Davis method in accordance with principles recommended by the JMPR. In addition, the procedure of evaluation was validated according to the principles laid down by the JMPR (Joint Meeting on Pesticide Residues). The detection rate of pesticide residues in all marketplace samples was less than 20% in Jinan City. The unqualified rate of vegetables was low (0.6%). The chlorothalonil was found as the pesticide with the highest rate of detection. The vegetables with the highest rate of pesticide residues detected were leafy vegetables. The relationship between variability factor and mean value of concentrations of contaminations was expressed by the formula, v=4.9×Cmean. The pesticide residues in vegetables from Jinan City is low. The evaluated variability factor is larger than that the value recommended by the JMPR, however, less than the default value used for acute intake assessment of pesticide residues in UK in most cases.