Scientia Agricultura Sinica

Isolation and Expression Analysis of a TaHin1 Gene Induced by Stripe Rust Fungus in Wheat

DENG Lin,WANG Xiao-jie,LIU Xin-ying,CAI Gao-lei,TANG Chun-lei,WEI Guo-ron,HUANG Li-li,KANG Zhen-sheng

Scientia Agricultura Sinica. 2010, 43(10): 1977-1984 . doi:10.3864/j.issn.0578-1752.2010.10.001

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【Objective】 A novel Hin1 gene induced by the stripe rust pathogen was cloned from wheat to better understand its role in wheat defense to Puccinia striiformis f.sp. tritici and to abiotic stresses. 【Method】 In-silico cloning and RT-PCR were combined to isolate a gene which might encode HIN1 from wheat Suwon 11 infected by stripe rust pathogen. Bioinformatics tools were applied to analyze both the DNA sequence and protein sequence. The expression patterns of the gene in wheat organs, as well as interactions with stripe rust pathogen, induction of exogenous phytohormones and abiotic stresses, were investigated using real time quantitative RT-PCR. 【Result】 The wheat Hin1 gene designated as TaHin1 was obtained. Open reading frame (ORF) of TaHin1 was 642 bp in length, encoding 213 amino acid residues with a molecular weight of 23.24 kD and predicted pI value of 8.67. TaHIN1 might be a secreted protein, containing a signal peptide and a HIN1 domain. TaHIN1 shared about 80% similarity with HIN1 from broomcorn and rice. TaHin1 expresses in wheat leaf, stem and root with no significant difference. Challenged by stripe rust fungus, TaHin1 was induced by Puccinia striiformis f.sp. tritici only in incompatible interaction. TaHin1 was up-regualted by exogenous salicylic acid and jasmonic acid while down-regulated by abascisci acid. Exogenous ethylene could not induce the expression. TaHin1 was obviously up-regulated by various abiotic stresses such as high salinity, drought, mechanical wound and low temperature. 【Conclusion】 TaHin1 gene was firstly cloned and characterized from wheat infected by stripe rust fungus. TaHin1 might facilitate wheat defence through salicylic acid and jasmonic acid pathways, while abscisci acid might play a negative role in the defence. TaHin1 also played a role in response to abiotic stresses.

Isolation and Primary Analysis of Protein Structures and Expression Patterns Responding to Different Light Treatments of Two Phytochrome A Genes in Maize (Zea mays L.)

MA Yan-bin,LI Zhuang,CAI Ying-fan,ZHOU Peng,XIAO Yang,HUANG Yu-bi,FU Feng-ling,PAN Guang-tang,YANG Ke-cheng,YANG Jian-ping

Scientia Agricultura Sinica. 2010, 43(10): 1985-1993 . doi:10.3864/j.issn.0578-1752.2010.10.002

Abstract ( 826 )

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【Objective】 The protein structures and domain functions of two phytochrome genes of maize (Zea mays L.) (ZmPhyA1 and ZmPhyA2) were analyzed. The expression patterns of ZmPhyA1 and ZmPhyA2 responding to different light treatments were detected. 【Method】 The full cDNA of ZmPhyA1 and ZmPhyA2 were cloned through RT-PCR from maize inbred line of B73. The putative domains of ZmPHYA1 and ZmPHYA2 proteins were predicted via the NCBI Protein BLAST. The physical interactions between different functional domains of ZmPHYA1 and ZmPHYA2 were confirmed using yeast two hybrid system. Their expression levels were detected using semi-quantitative RT-PCR assay. 【Result】 Phylogenetic tree analysis indicated that ZmPHYA2 was more close with SbPHYA (Sorghum bicolor) than with ZmPHYA1. Both of ZmPHYA1 and ZmPHYA2 were composed of a GAF domain, a phytochrome domain, two PAS domains, a His Kinase A domain and a Histidine kinase-like ATPase domain. ZmPHYA1 and ZmPHYA2 were physically able to interact with themselves and each other through the 539-amino acids in their C terminal domains. Both of ZmPhyA1 and ZmPhyA2 showed higher expression lelvels in darkness, far-red and blue light conditions, but lower in red and white light conditions. 【Conclusion】 The ZmPHYA1and ZmPHYA2 proteins belong to active photo-receptor in maize as PHYA does in model plant Arabidopsis. The expression of ZmPhyA1 and ZmPhyA2 rapidly corresponded to dark, far-red, red and blue light treatments.

Cloning of Glycine Max 2-Methyl- 6-Phytyl-1,4-Benzoquinol Methyltransferase (Gm VTE3) Gene and Engineering Vitamin E Content in Seed of Transgenic Tobacoo

XU Miao-yun,ZHOU Jian,ZHANG Lan,FAN Yun-liu,WANG Lei

Scientia Agricultura Sinica. 2010, 43(10): 1994-1999 . doi:10.3864/j.issn.0578-1752.2010.10.003

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【Objective】 VTE3 is a key enzyme in vitamin E pathway. A VTE3 like gene (Gm VTE3) was cloned from soybean, and the expression of Gm VTE3 in tobacco and effect on tocopherol composition of seed were studied. 【Method】 A putative VTE3 was cloned and characterized from soybean via EST sequence splicing and RT-PCR, the expression was analyzed and the effect of overexpression of Gm VTE3 on tocopherol composition of seed was studied in tobacco.【Result】The full-length cDNA of Gm VTE3 is 1 026 bp, which encodes a polypeptide of 342 amino acids. The amino acid homologies of MPBQ MT among different species share higher similarities. Expression of Gm VTE3 in transgenic tobacco increased the ratio of γ-tocopherol and δ-tocopherol by two times compared with the control. 【Conclusion】 Gm VTE3 is the first VTE3 cloned in soybean and may catalyze the methylation of 2-methyl-6-phytyl-1,4 benzoquinol in tobacco plant and alter seed tocopherol composition. These findings demonstrate that the gene identified in Glycine max may be used to alter the tocopherol composition of other commercial seed oils.

A Preliminary Analysis of Differential Proteins Between Brassica napus Resistance to Sclerotinia sclerotiorum Near-isogenic Lines and Susceptible Parent

HUANGFU Hai-yan,GUAN Chun-yun

Scientia Agricultura Sinica. 2010, 43(10): 2000-2007 . doi:10.3864/j.issn.0578-1752.2010.10.004

Abstract ( 1059 )

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【Objective】 A trichoroacetic acid/acetone method was established for extracting the full leaf-proteins of rapeseed which provided the reference for the rapeseed proteomics research in the future. The difference in protein expression was identified after the resistance and susceptibility to Sclerotinia sclerotiorum rapeseed were induced by Sclerotinia sclerotiorum. It offered the clues to searching for the resistance to Sclerotinia sclerotiorum genes.【Method】 Near-isogenic lines 98C40 (the antigen derived from Xiangyou 15) is resistant to Sclerotinia sclerotiorum and the parent 98C40 is susceptible to Sclerotinia sclerotiorum which were inoculated with Sclerotinia sclerotiorum during their seedling stage. Seventy-two hours after inoculation, full leaf-proteins of them were extracted respectively. Two-dimensional electrophoresis (2-DE), PD-quest software and mass technology were used in differential proteomics analysis. 【Result】 Significant difference of 4 protein spots were observed between them. Protein spot a is mitochondrial F1 ATP synthase beta subunit, spot c is phosphoglycerate kinase and spot d is thiazole biosynthetic enzymes (THI1), which express only in 98C40 (the antigen derived from Xiangyou 15) not expressed in parent 98C40. Protein spot b is ribulose-1,5-bisphosphate carboxylase/oxygenase expressed highly in 98C40 (the antigen derived from Xiangyou 15) and lowly in parent 98C40 based on 5 times difference of expression. 【Conclusion】 The four proteins are all closely related to the rapeseed metabolism. They may play a role in resistance to Sclerotinia sclerotiorum.

A Rank-Sum-Difference Testing Method for Multi-Trait Comprehensive Ranking

LUO Ru-jiu,HU Zhi-qiu,SONG Wen,XU Chen-wu

Scientia Agricultura Sinica. 2010, 43(10): 2008-2015 . doi:10.3864/j.issn.0578-1752.2010.10.005

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【Objective】 The former paper had proposed the rank-sum testing method for multi-trait comprehensive evaluation, which not only can make the multi-trait comprehensive ranking, but also test the significance of difference between evaluation objects and the average level. In this paper, a rank-sum-difference testing method for multi-trait comprehensive evaluation was studied to implement the multiple comparisons among evaluation objects. 【Method】 The theoretical distribution of rank-sum-difference, based on the theoretical distribution of rank-sum, was firstly deduced by using combinatorial mathematics.【Result】 Furthermore, it was used to obtain the critical values for the rank-sum-difference testing in multi-trait comprehensive evaluation. 【Conclusion】 The proposed rank-sum-difference testing method is so simple and convenient that it can be easily used to realize multiple comparisons among various evaluation objects.

Effect of Auxin on Al-Induced Malic Acid Efflux in Wheat with Differential Al Tolerance

YANG Ye,WANG Qiao-lan,GENG Ming-jian,GUO Zai-hua,ZHAO Zhu-qing

Scientia Agricultura Sinica. 2010, 43(10): 2016-2022 . doi:10.3864/j.issn.0578-1752.2010.10.006

Abstract ( 1065 )

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【Objective】 The effects of indole-3-acetic acid (IAA) on malic acid secretion in wheat roots were studied under Al stress. The mechanism of malic acid secretion difference of different Al-tolerant wheat varieties was investigated. 【Method】Hydroponic experiments were performed by two wheat (Tritium aestivum L.) cultivars, ET8 (Al-resistant) and ES8 (Al-sensitive). The effects of exogenous IAA, N-1-napthyl-phtalamic acid (NPA), 2, 3, 5-triiodobenzoic (TIBA), anthracene-9-carboxylic acid (A9C)and niflumic acid (NIF) on secretion rate of malic acid were investigated. 【Result】 Effects of different concentrations of IAA (0, 25, 50, and 100 μmol•L-1) treatments on the secretion of malic acid were not observed in both ET8 and ES8. After a pretreatment with 50 μmol•L-1 Al for 3 h, different concentrations of IAA were applied at the Al free condition for 24 h, the secretion of malic acid increased significantly with the increasing concentrations of IAA in the ET8 but not ES8. Compared to Al (50 μmol•L-1) treatments, the secretion of malic acid in ET8 increased significantly under the co-treatment of IAA (50, 100 μmol•L-1) and Al (50 μmol•L-1), but no significant changes were seen in ES8 under the co-treatments of IAA (25, 50 μmol•L-1) and Al (50 μmol•L-1). Compared to Al (50 μmol•L-1) treatments, the secretion rate of malic acid in ET8 and ES8 decreased under the co-treatments of IAA transport inhibitors NAP (TIBA) and Al (50 μmol•L-1). Results above suggested that IAA involved in the Al-induced malic acid secretion. Compared to Al (50 μmol•L-1) treatments, significant decrease of malic acid secretion rate were observed in ET8 and ES8 under the co-treatments of 5 μmol•L-1 A9C (NIF) and Al (50 μmol•L-1). Compared to the co-treatments of A9C (NIF) and Al (50 μmol•L-1),significant increase of malic acid secretion rate were observed in ET8 and ES8 under the co-treatments of different concentrations of IAA, 5 μmol•L-1 A9C (NIF) and Al (50 μmol•L-1). Results above suggested that IAA may regulate Al-induced malic acid secretion of wheat roots via anion channel. 【Conclusion】 On the condition that malic acid secretion pathway was activated by Al, the secretion of malic acid could be increased by IAA. The different regulation effects of IAA on the secretion of malic acid of wheat with different Al-tolerant levels related with the difference of malic acid secretion.

Exploration of Digital Plant and Its Technology System

ZHAO Chun-jiang,LU Sheng-lian,GUO Xin-yu,XIAO Bo-xiang,WEN Wei-liang

Scientia Agricultura Sinica. 2010, 43(10): 2023-2030 . doi:10.3864/j.issn.0578-1752.2010.10.007

Abstract ( 995 )

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Digital plant is the foundation of digital agriculture. Digital plant tries to explore plant kingdom by using digitized methods, and also provides information services and technology platform for digitized description, growth modeling, process simulation, visualized calculation and analysis, collaborative experiment, model sharing and integrated applications of plant-life systems. It is of great significance for discussion of digital plant and its technology system. In this paper, the concept of digital plant is introduced with a detail analysis of the basic research issues in this area. The academic foundation and technology system for digital plant are then discussed with an in-depth discussion of the strategic emphases of its research issues and strategies are to be expected. This research may provide a reference for the further development of digital plant.

Biocontrol Potential of Trichoderma virens Strain TY009 Against Rice Sheath Blight and Other Main Fungal Diseases

LIU Lu-ning,TU Yan-la,ZHANG Jing-ze

Scientia Agricultura Sinica. 2010, 43(10): 2031-2038 . doi:10.3864/j.issn.0578-1752.2010.10.008

Abstract ( 1212 )

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【Objective】 Biocontrol potential of strain TY009 was assessed in the round by its antagonism against Rhizoctonia solani as well as Magnaporthe oryza and Ustilaginoidea virens, including the effect of pH and heat on its stability of gliotoxon. 【Method】 Gliotoxin was seperated from liquid media of Trichoderma virens strain TY009 and it was purified by chromatographic methods. Antagonistic action of strain TY009 against R. solani was determined by dual culture assay. The inhibitory activities of gliotoxin against the hypha growth and sclerotial germination of R. solani, conidial germination and appressorial formation of M. oryza and conidial germination and secondary conidium formation of U. virens, were assessed in laboratory, including the effects of heat and pH on bioactivity of gliotoxin. 【Result】 The antagonism of strain TY009 against R. solani was significant. The inhibitory activities of gliotoxin demonstrated that there was no hypha growth of R. solani in 150 μg•mL-1 of gliotoxin solution and sclerotial germination which was treated for 4 h in 160 μg•mL-1. There was no conidial germination and appressoria formation of M. oryza in 50 and 10 μg•mL-1of gliotoxin solution, respectively, and no conidial germination and secondary spore formation of U. virens in 1.0 μg•mL-1. The bioactivity of gliotoxin against the hyphae of R. solani did not change at 100℃ for 1 h, but in condium suspension of U. virens with 0.5 μg•mL-1 of gliotoxin, the bioactivity of gliotoxin against conidial germination and secondary conidium formation was not significant in the conidium suspension with a pH greater than 6.0 and significant with low pH. 【Conclusion】 T. virens strain TY009 possesses multiple mechanisms of antifungal activity and it is considered to be a potential biological control agent for biocontrol of rice sheath blight and, rice blast and rice false smut

Response to Illumination Induction and Effect of Temperature on Lesion formation of lrd (Lesion Resembling Disease) in Rice

WANG Jian-jun,ZHANG Li-xia,WANG Lin-you,ZHANG Li-hua,ZHU Chao-na,HE Zu-hua,JIN Qing-sheng,FAN Hong-huan,YU Xin

Scientia Agricultura Sinica. 2010, 43(10): 2039-2044 . doi:10.3864/j.issn.0578-1752.2010.10.009

Abstract ( 876 )

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【Objective】 To determine the spectral range of light required for lesion formation and the effect of temperature on the expression of lrd lesions, the response of lrd expression to light and temperatures was tested for certain mutants in Oryza sativa L. 【Method】 Six lrd mutants derived from Indica and Japonica by gamma-ray mutagenesis simultaneously were illuminated by Light Emitting Diode (LED) light and were cultured in two different growth chambers set at three different temperature regimes. Lesions occurred on leave were observed and photographed for comparison the effect of different treatments. 【Result】 The expression of lrd lesions for lrd31 was induced by UV light, that of lrd36 was induced by yellow light, that of lrd37and lrd35 was induced by blue light, and lrd32 or lrd40 expressed lesion under all illuminated light. lrd32, lrd36 and lrd37 formed lesion under all culturing temperatures, and cooler environment accelerated their lesion expression, lrd35 and lrd40 were suppressed at high temperature and expressed at intermediate temperature, also accelerated under lower temperature. But lrd31 formed lesion only under intermediate temperature, and no lesion formation at high or lower culturing temperature. 【Conclusion】 The expressions of lrd lesions are light-dependent, different genotypes of lrd mutants in rice need specially spectral range of light. Temperature is another factor influencing lrd expression. The lower temperature seemed to enhance the expression of lrd phenotype.

Characteristics of PLFA Biomarkers for the Endophytic Bacteria Inside Musa Plants

LAN Jiang-lin,LIU Bo,CHEN Lu,XIAO Rong-feng,SHI Huai,SU Ming-xing

Scientia Agricultura Sinica. 2010, 43(10): 2045-2055 . doi:10.3864/j.issn.0578-1752.2010.10.010

Abstract ( 954 )

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【Objective】 The present paper dealt with isolation and identification of the endophytic bacteria from Musa plants as well as the characteristics of their PLFA biomarkers. 【Method】 Healthy Musa plants were collected from Zhangzhou areas in Fujian province, China. The endophytic bacteria inside the plants were isolated by streak plate method and identified by using fatty-acid identification technology. 【Result】 The results showed that 14 species of endophytic bacteria were identified by means of microbe identification system. 9 microbial species belonged to Musa itinerans, 7 species belonged to Musa AAA cavendish var.Williams and 3 species belonged to Musa basjoo. There were 35 PLFA biomarkers detected in 14 species of endophytic bacteria, in which based on the distribution frequency in 4 types of bacteria were clustered, e.g. (1) high frequency related to characteristics of microbe in general and the PFLA were detected in 10-14 times in 14 strains of bacteria, (2) middle frequency related to bacteria in general and the PFLA were detected in 4-6 times in 14 strains of bacteria, (3) low frequency related bacterial genus and the PFLA were detected in 2-3 times in 14 strains of bacteria, (4) tiny frequency related to species and the PFLA only in a bacteria. According to the PLFA biomarkers and the cluster analysis method, the 14 species were classified into 3 groups based on the PLFA biomarkers. The diversity and richness, uniformity and dominance of the concept index ecology were used to analyze the relationship between the fatty acid biomarker gross and ecological parameters. The results showed that the richness of 16:0,18:1 W7C, 14:0, 12:0, 18:0, and 17:0 CYCLO of PLFA biomarkers was relatively high. The higher fatty acids biological response value, the lower the sum uniformity (J), the dominance of the Simpson index (D), Shannon-Wiener (H1), Brillouin (H2), Mcintosh (H3) diversity index were relatively high. 【Conclusion】 There are significant polymorphism among community structure of endophytic bacteria and their PLFA biomarkers in Musa plants.

Effects of Wheat Varieties on Population Parameters of Macrosiphum avenae (Fabricius)

GUO Xiao,LI Ke-bin,YIN Jiao,WANG Bing,CAO Ya-zhong

Scientia Agricultura Sinica. 2010, 43(10): 2056-2063 . doi:10.3864/j.issn.0578-1752.2010.10.011

Abstract ( 963 )

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【Objective】 Two successive generations of Macrosiphum avenae (Fabricius) were studied for effects of wheat varieties on the aphid population parameters such as number of alate aphid, generation time and survival rate, also the aphid physiological parameters such as nymph developmental duration, adult longevity, fecundity, body weight, and wing-type differentiation. 【Method】 Using systematic caging methods, the population and physiological parameters were investigated on 10 wheat strains. 【Result】 There were significant differences between the varieties of M. avenae in host selection. Phototaxis of the resistant varieties to aphid was more evident. The results showed that for the parameters: Developmental duration of nymph was longer on resistant varieties; the survival rate of nymph, adult longevity, fecundity and body weight were significantly decreased. The number of alate aphids on resistant varieties was larger than that on susceptible varieties. The effects of resistant hosts to aphid physiology are perhaps exacerbated by comparing the physiological parameters through the two generations of wheat aphids. 【Conclusion】 Resistant wheat varieties have phototaxis and antibiosis to Macrosiphum avenae (Fabricius). The antibiosis of wheat to aphid has cumulative effects as aphid generations continue.

Inhibitory Effects of Tebufenozide on Phenoloxidase from 5th Instar Larvae of Spodoptera exigua

QIU Xiu-cui,LIU Yong-jie,JIAO Yan-yan,LIU Hui

Scientia Agricultura Sinica. 2010, 43(10): 2064-2071 . doi:10.3864/j.issn.0578-1752.2010.10.012

Abstract ( 851 )

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【Objective】 In this paper, the inhibitory effect of tebufenozide on phenoloxidase (PO) in 5th instar larvae of the common armyworm, Spodoptera exigua, was determined. 【Method】 Fifth instar larvae of S. exigua were supplied with tebufenozide-treated artifical diet to eat for different times and the inhibitory effect of tebufenozide on PO extracted from tebufenozide-treated and non-treated 5th instar larvae were determined by biochemical methods. 【Result】 The results indicated that tebufenozide could inhibit PO activity obviously, and the inhibition concentration of tebufenozide mixed with PO directly leading to 50% activity loss (IC50) was 5.43 µmol•L-1. The inhibitory mechanism of tebufenozide on PO was a mixed-competitive inhibition for oxidation of O-dihydroxybenzene, the dissociative enzmye inhibition constant (K i) and E-S’ inhibition constant (Kis) were 11.223 µmol•L-1 and 34.036 µmol•L-1, respectively. This inhibition may carry out through tebufenozide directly combining with enzyme protein while may be not chelating with Cu2+ in the active center of PO. The PO activity in head, hemolymph and epidermis of 5th instar larvae was also significantly inhibited after the larvae were treated with two sublethal doses (28.41 µmol•L-1 and 85.23 µmol•L-1) of tebufenozide for continuous 24, 48 and 72 h, respectively. The inhibition rates increased with tebufenozide-treated time increasing, and inhibition rates of 85.23 µmol•L-1 were almost higher than those of 28.41 µmol•L-1 in the same tissues at the same length of tebufenozide-treated times. The orders of inhibition rates of PO by tebufenozide in different tissues at the same length of times were head > hemolymph > epidermis. 【Conclusion】 Tebufenozide can significantly inhibited PO activity, and it may be infer that the interference of new cuticle developmemt of larvae by tebufenozide is closely related to the inhibition of PO activity by tebufenozide.

Effect of Long-Term Application of K Fertilizer and Wheat Straw to Soil on Potassium Fixation Capacity of Selected Soils from Northern China

TAN De-shui,JIN Ji-yun,HUANG Shao-wen,LIU Zhao-hui,JIANG Li-hua

Scientia Agricultura Sinica. 2010, 43(10): 2072-2079 . doi:10.3864/j.issn.0578-1752.2010.10.013

Abstract ( 1087 )

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【Objective】 Experiments were conducted to study the difference of potassium fixation capacity. 【Method】Fixed-site researches on cultivated layer of soil under long-term application of K fertilizer and wheat straw to soil for 13 continuous years in selected regions of north China were carried out. After 13 years, soil samples of different treatments collected from each fixed-site were treated with different concentrations of KCl solution to study K fixation capacity of typical soil in northern China.【Result】 The results showed that continuous application of K fertilizer and wheat straw could reduce the fixation rate of added K significantly, and when the concentration of K increased from 1 000 mg•L-1 to 4 000 mg•L-1 in the soil solution, K fixation capacity of soils increased at the same time. In the same region, K fixation rate of soils in double cropping regime was higher than that in single cropping regime. K fixation capacity of soil showed a clear increasing trend of distribution from the west to the east. When the K concentration in the surrounding solution was 1 000 mg•L-1, the average K fixation rates of soils in NP treatment were 348.5, 442.9, and 468.5 mg•kg-1 in Northwest, North China and Northeast China, respectively. 【Conclusion】 Difference in potassium fixation rate between soils with depletion of K successively and soils supplied with K successively is an important character for judging the condition of soil potassium.

Effects of Different Mulching Patterns on Soil Water-Holding Capacity of Non-Irrigated Apple Orchard in the Weibei Plateau

GAO Mao-sheng,LIAO Yun-cheng,LI Xia,HUANG Jin-hui

Scientia Agricultura Sinica. 2010, 43(10): 2080-2087 . doi:10.3864/j.issn.0578-1752.2010.10.014

Abstract ( 876 )

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【Objective】 The objective of the experiment was to study the effect of different mulching patterns on soil water-holding capacity of apple orchard in the Weibei Plateau, and to provide a scientific basis for orchard soil and water management. 【Method】 The effects of straw mulching, film mulching, sod mulching on soil porosity and soil water-holding capacity of non-irrigated apple orchard within 100 cm soil layer were studied by soil moisture measurement in the orchard. 【Result】 Straw mulching enhanced soil porosity and increased the soil water-holding capacity within 60 cm soil layer, and after three years later of mulching, the average soil porosity in 0-60 cm layer of treatments was straw mulching＞sod mulching＞no mulching＞film mulching. The treatment of film mulching decreased soil porosity. The soil saturated water content, soil absorbed water content and soil retained water content in straw mulching treatment within 60 cm increased by 2.18 mm, 0.84 mm, and 1.34 mm compared to no mulching, increased by 2.52 mm, 1.15 mm, and 1.36 mm compared to film mulching, The soil saturated water content, soil absorbed water content and soil retained water content in sod mulching treatment within 60 cm increased by 2.01 mm, 0.69 mm, and 1.32 mm compared to no mulching, increased by 2.35 mm, 1.00 mm, and 1.34 mm compared to film mulching;Straw mulching increased soil water-holding capacity within 100 cm effectively in May and September. In May, straw mulching soil water-holding capacity within 100 cm increased by 48.85 mm compared to no mulching and increased by 31.71 cm in September. Sod mulching soil water-holding capacity was the lowest in all treatments in May, decreased by 31.71 mm compared to no mulching and there was no significant difference between sod mulching and no mulching in September. 【Conclusion】 In the apple production base of Weibei Plateau, the use of straw mulching technology can play a better role in the preservation of soil moisture, and the soil water-holding capacity within 100 cm increased significantly.

Analysis of the Potential Influence of Global Climate Change on Cropping Systems in China Ⅲ. The Change Characteristics of Climatic Resources in Northern China and Its Potential Influence on Cropping Systems

LI Ke-nan,YANG Xiao-guang,LIU Zhi-juan,WANG Wen-feng,CHEN Fu

Scientia Agricultura Sinica. 2010, 43(10): 2088-2097 . doi:10.3864/j.issn.0578-1752.2010.10.015

Abstract ( 997 )

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【Objective】 Under the background of global climate change, the obvious changes that had taken place in heat and precipitation resources in northern China were studied. Furthermore, the possible effects of climate warming on the agro-climatic resources and cropping systems in northern China were analyzed. 【Method】 Based on 308 meteorological observations stations from 14 provinces (municipalities and autonomous regions) in northern China, the inter-decadal and spatial variation trends of heat and precipitation resource were analyzed. According to the climatic regionalization indicators of cropping systems in China, the spatial displacement of planting north boundary during 1950s—1980 and 1981—2007 was analyzed. The major method used was choosing typical stations in the sensitive zone of cultivation northern boundary, and crop potential productivity step correction method to calculate the potential yield change due to cropping pattern shift between one crop (spring maize, spring wheat, winter wheat) a year and two crops (winter-summer maize) a year. 【Result】 Temperatures in northern China had generally increased, ≥0℃ accumulated temperature zone showed a north shift and a west spread, the cumulative effects of temperature rising were significant, the climatic tendency of cumulative temperature was 65.5 ℃•d/10a. Distribution of annual precipitation had presented a regional difference and reduced from southeast to northwest. Along to this, in the whole region it also showed a decreasing trend, the climatic tendency of precipitation varied from -90.0 mm/10a to 23.0 mm/10a, with an average level of -10.6 mm/10a. Under the combined effect of heat and precipitation, in the research area, the area of one-crop of cool-warm plants in semi-arid medium plateau in north (Ⅱ) declined, in area of one-crop of warm-cool plants in semi-arid low plateau in northeast and northwest (Ⅲ) increased in northeast China, and declined in North China and northwest China. The area of one-crop of warm-cool plants in semi-humid plain or hilly in northeast (Ⅳ) increased and the north boundary moved north in area of two-crops in irrigated land and two/one-crop in dry land in Huanghuaihai region (Ⅵ). Generally speaking, the northeast area boundary had a remarkable change, but was gradual and insignificant in southwest. In the sensitive areas which showed planting system’s north boundary changes, crop potential productivity increased significantly, from the area of one-crop of warm-cool plants in semi-humid plain or hilly areas in northeast (Ⅳ) to the area of two-crops a year, the yield increased by 1 979 kg•hm-2, which means that the annual production per unit area increased by 15.3%; from the area of one-crop of warm-cool plants in semi-arid low plateau in northeast and northwest (Ⅲ) to the area of two-crops a year, the yield increased by 7 912 kg•hm-2, which means that the annual production per unit area increased by 155.2%; in the area of one-crop of warm-cool plants in semi-arid low plateau in northeast and northwest (Ⅲ) where the spring wheat is changed to spring maize, the yield increased by 2 873 kg•hm-2, which means that the annual production per unit area increased by 51.7%. 【Conclusion】 In the context of global climate change, the≥0℃ accumulated temperature increased while the precipitation showed a decreasing trend in the research region. All of these caused a northwest movement of the north boundary line in sensitive zones of planting boundaries and the cropping system changes resulted in the increase of annual production per unit area.

Annual Dynamics of Zinc Contents in Apple Trees Under Different Zinc Levels of Apple Orchard

WANG Yan-an,YAN Zhi-gang,ZHANG Yuan-zhen,LI De-quan,SHU Huai-rui,ZHANG Fu-suo

Scientia Agricultura Sinica. 2010, 43(10): 2098-2104 . doi:10.3864/j.issn.0578-1752.2010.10.016

Abstract ( 1112 )

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【Objective】 In order to explain the dynamic changes of absorption and transportation of zinc in apple tree with different zinc content level of apple orchard, the annual regularity of distribution and transportation of zinc nutrition was studied. 【Method】 Zinc concentration in soil and organs from apple cultivar ‘Fuji’ with rootstock M . hupehensis Rehd in the diseased apple tree (lack zinc) and the normal apple tree were determined at different stages. 【Result】 The concentration and the annual regularity of soil zinc nutrition in both diseased apple tree (lack zinc) and normal apple tree was consistent, but the content of zinc in 20-40 cm layer of diseased tree was lower than that of normal tree. The difference of root zinc concentration between diseased and normal tree was significant, the root of diseased trees showed a rise-and-fall motif, but in normal tree it kept higher level. The content of zinc in perennial shoots of normal tree kept high level, and increased in later period of development, but the diseased tree showed an inverse tendency. The tendency of the changes of zinc concentration in new organs under different zinc levels were similar in general, but the concentration of zinc in normal trees exhibited more than that of diseased trees. 【Conclusion】 The lower content of available zinc in the layer where the apple tree roots concentrated was the main reason for the diseased trees (lack zinc), besides, the diseased trees resulted in the lower transportation index of upward/roots of zinc induced by zinc restoration in the lower position in later period of development and the inhibition of zinc uptake of apple trees. Meanwhile, Zn-deficiency disturbed the rhythm of zinc absorption of trees and resulted in that the diseased trees formed specific zinc translocation regularity, i.e. the zinc supplying ability of roots was low in spring and summer and had difficulty to uptake zinc while large amount of zinc was restored in roots in the later period of development.

Cloning, Subcellular Localization and Expression Analysis of SPL9 and SPL13 Genes from Poncirus trifoliata

SONG Chang-nian,QIAN Jian-lin,FANG Jing-gui,WANG Hua-kun,QIU Xue-lin,ZHANG Zhen, ZHANG Xiao-ying

Scientia Agricultura Sinica. 2010, 43(10): 2105-2114 . doi:10.3864/j.issn.0578-1752.2010.10.017

Abstract ( 921 )

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【Objective】 This study aimed to clone two full length cDNA of SPL9 and SPL13 SBPs (SQUAMOSA promoter binding proteins) transcription factors from Poncirus trifoliata (L.) Raf. and construct expression vectors of SPL9 and SPL13 for subcellular location analysis. Real time PCR was used to determine the tissue expression patterns of SPL9 and SPL13 for analysis of the role of SPL9 and SPL13 during growth and development in adult P. trifoliata. 【Method】 Bioinformatics analysis and RACE technology showed that the complete cDNAs cloned, designated as Pt-spl9 and Pt-spl13, was 1 519 bp and 1 824 bp in length, respectively. The sequences were deposited in GenBank database with accession no. of FJ502237 and FJ502238. Recombinant plasmid 35S-GW-FJ502237/FJ502238-GFP was introduced into onion epidermal cells by the particle bombardment method with a PDS1000/He. Transformed cells were incubated for 24 h at 22℃ in the dark and green fluorescence was monitored under a laser scanning confocal microscope. The SYBR Green I Real-time qRT-PCR was employed to analyze the expression of Pt-SPL9 and Pt-SPL13 in young leaf, stem, root, bud flower, flower, fruit and other organs. 【Result】 Bioinformatics analysis showed that the cDNA of Pt-SPL9 and Pt-SPL13 had the recognition sites of microRNA156. The deduced amino acid sequence of Pt-SPL9 and Pt-SPL13 were 388 and 379 residues, which were 48.9 %, 42.5 %, 41.7 % identical, respectively, with SPL9 of Antirrhinum majus, Arabidopsis thaliana and Zea mays; and 40.8%, 38.1%, 35.8% identical respectively with SPL13 of Arabidopsis thaliana, SPL16 of Oryza sativa, and TGA1 of Zea mays, respectively. Pt-SPL9 and Pt-SPL13 and other plant SBPs have the same amino acid sequences that are highly conserved as the designed SBP domain and two-way nuclear localization signal. Subcellular localization results showed that the Pt-SPL9 and Pt-SPL13 were localized in the nucleus. SYBR Green I real-time quantitative RT-PCR results showed that the Pt-SPL9 and Pt-SPL13 were expressed ubiquitously in various organs and tissues, but the expression levels were different. The expression of Pt-SPL9 was highest in the stem, and lower in flowers and leaves, and lowest in the root, flower buds and young fruit; Pt-SPL13 was expressed highest in young fruit, and the expression levels in the stems and flower buds were high too. Its expression level in leaves was not high and those in flowers and roots were very low. 【Conclusion】 Transcription factor Pt-SPL9 and Pt-SPL13 all have nuclear localization function, Pt-SPL9 and Pt-SPL13 might play important roles in trifoliate orange development.

Production and Characterization of Interspecific Hybrids Between Welsh Onion and Onion

WANG Yong-qin,TIAN Bao-hua,LIANG Yi

Scientia Agricultura Sinica. 2010, 43(10): 2115-2121 . doi:10.3864/j.issn.0578-1752.2010.10.018

Abstract ( 870 )

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【Objective】 The objective of the study is to develop the interspecific hybrid plants between welsh onions and onion. 【Method】 The Zhangqiu welsh onion and onion inbred line 06-38 were used to make distant hybridization. The ovary of distant hybrids were cultured. The hybrid plants were identified by CAPS. The fertility was identified by pollen staining, in vitro germination and self-pollination. 【Result】 Under the natural conditions, the embryo of the welsh onion×onion reciprocal cross plants was abortive. The seventh day after pollination was the best time for the ovary culture. The ovarys were cultured on the MS medium without hormone and the welsh onion×onion reciprocal crosses were obtained from the interspecific F1 hybrid. Through ovary culture, 26 hybrid plants of the welsh onion × onion and 22 hybrid plants of onion × onion were obtained. All of the tested hybrids were the true hybrid by CAPS. The F1 hybrid plants had obvious heterosis and hybrid male sterility. 【Conclusion】 By using the ovary culture technique, the interspecific hybrid F1was obtained, thus overcoming the welsh onion×onion distant hybrid which is abortive under natural conditions. The hybrid plants showed apparent heteroses and male sterility.

Principal Components Analysis and Cluster Analysis of Flavor Compositions in Waxy Corn Soft Can

SONG Jiang-feng,LI Da-jing,LIU Chun-quan,LIU Yu-hua

Scientia Agricultura Sinica. 2010, 43(10): 2122-2131 . doi:10.3864/j.issn.0578-1752.2010.10.019

Abstract ( 968 )

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【Objective】 The main factors affecting the flavor quality of different varieties of sweet waxy corn soft can were analyzed, for exploring the possibility that using volatile components as indicators for characterization and differences, also for providing a theoretical basis for target species selection. 【Method】 The head space-solid phase microextraction (HS-SPME) method was used to extract the volatile components from six varieties of corn soft can. The extracted volatile components were analyzed by gas chromatography-mass spectrometry (GC-MS) method. And principal component analysis and cluster analysis were adopted to investigate their flavors. 【Result】 The results showed that different species of waxy corn soft can could have inherent flavor components, the main flavor components of Longnian 2 soft can were assigned to 2, 3-dihydro-benzo furan, 2-furan methanol and furaldehyde, the major flavor components of Jingtian 1 soft can were assigned to 2, 5-dimethyl pyrazine, 3-methyl-2-thiophene carboxaldehyde, the flavor components of Jiangnanhuanuo soft were assigned to (Z) -2-heptenal. 【Conclusion】 All these component differences were in their flavor style differences.

Antioxidation Role of Procyanidins from Lotus Seedpod in Oils

YU Hua-juan,SUN Zhi-da,XIE Bi-jun

Scientia Agricultura Sinica. 2010, 43(10): 2132-2140 . doi:10.3864/j.issn.0578-1752.2010.10.020

Abstract ( 1136 )

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【Objective】 The antioxidation of procyanidins from seedpod of lotus(LSPC) in oils and fats was studied in order to offer a theoretial basis for the development of natural and healthy antioxidant. 【Method】 Add some different concentrations of LSPC or make LSPC combinations with lecithin or vitamin E in oils and fats to investigate the antioxidation of LSPC in oleic acid and animal oils and vegetable oils. The system of linoleic acid was used to show the inhibitor of LSPC to lipoxygenase. 【Result】 LSPC had different antioxidant effects on animal oils and vegetable oils: tea oil＞lard oil＞cotton oil＞bean oil. It can prolong the induction period of tea oil for 2.2 times. Lecithin and vitamin E had excellent synergetic effecton LSPC. Especially when combied with vitamin E, it could prolong the induction period of oleic acid for 14.7 times, and prolong the induction period of lard oil for 3.6 times. LSPC had the same effects with tea polyphenol in inhibition of the activity of lipoxygenase. 【Conclusion】 LSPC has excellent antioxidation effects on oils and fats.

Antioxidative Activity of Lactobacillus casei subsp. casei SY13 on Ageing Model Mice

ZHANG Shu-wen,LÜ,Jia-ping,MENGHE Bilige,LIU Lu,HU Xian-bao

Scientia Agricultura Sinica. 2010, 43(10): 2141-2146 . doi:10.3864/j.issn.0578-1752.2010.10.021

Abstract ( 1057 )

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【Objective】 The objective of the experiment was to study the antioxidative activity of viable cells and heat-killing cells of Lactobacillus casei subsp.casei SY13 on aged model mice induced by D-galactose. 【Method】 ICR subacute aged model mice, which were given subcutaneous injection of D-galactose continuously, were fed with viable cells and heat-killing cells of Lactobacillus casei subsp.casei SY13. The content of malondialdehyde (MDA), activity of superoxide dismutase (SOD) , glutathione peroxidase (GSH-Px) and total antioxidant capacity (T-AOC) in serum and liver of the mice were tested. 【Result】 SY13 viable cells high dose group and middle dose group(20,10 mL•kg-1) could obviously reduce the aged mice serum and liver tissue MDA content , enhance evidently the GSH-Px activity and total antioxidant capacity (T-AOC), but the SOD activity did not change significantly.【Conclusion】Lactobacillus casei subsp. casei SY13 viable cells can obviously increase the antioxidant ability of ageing mice and has certain anti-aging effects.

Effects of Selenomethionine on Selenium Concentration in Plasma and Tissues and Antioxidant Capacity of Finishing Pigs

JIANG Zong-yong,WANG Yan,LIN Ying-cai,ZHENG Chun-tian,JIANG Shou-qun,CHEN Fang

Scientia Agricultura Sinica. 2010, 43(10): 2147-2155 . doi:10.3864/j.issn.0578-1752.2010.10.022

Abstract ( 823 )

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【Objective】 The experiment was conducted to investigate the effect of diet supplemented with selenomethionine (Se-Met) on plasma and tissue selenium content and antioxidant capacity of finishing pigs. 【Method】 Sixty-four crossbred (Duroc×Landrace× Largewhite) pigs (initial BW, 60 kg) were randomly allocated into 4 treatments on the basis of weight following a randomized complete block design. Four replicates were designed for each treatment. Pigs were fed with corn-soybean meal-based diets supplemented with 0 (control) or 0.15 and 0.30 mg•kg-1 Se from Se-Met or 0.30mg•kg-1 Se from sodium selenite (SS), respectively. One barrow per pen was slaughtered when all the pigs were weighed about 95kg on average. 【Result】 All Se-added groups showed significantly increased Se concentration in plasma, liver and longissimus muscle compared with the control (P＜0.01), also 0.30 mg•kg-1 Se (Se-Met) group compared to 0.15mg•kg-1 Se (Se-Met) group or SS group (P＜0.05). Adding Se-Met significantly raised plasma glutathione peroxidase (GSH-Px) activity, catalase (CAT) activity, total antioxidant capacity (T-AOC), and significantly decreased plasma malondialdehyde (MDA) content (P＜0.05). Diet supplemented with Se-Met significantly improved liver GSH-Px, CAT, SOD activity and T-AOC (P＜0.05). All Se-Met groups presented significantly higher liver SOD activity and 0.15 mg•kg-1 Se (Se-Met) significantly increased CAT activity with respect to SS group (P＜0.05). Longissimus muscle GSH-Px activity at 45min post-slaughter was significantly raised and carbonyl protein content was significantly reduced in all Se-added groups (P＜0.05). Longissimus muscle MDA content at different times after slaughter was significantly decreased in all Se-Met groups compared to control, also 0.30mg•kg-1 Se(Se-Met) group compared to SS group at 45min and 72h post-slaughter (P＜0.05). GSH-Px mRNA relative expression of longissimus muscle was significantly increased in all Se-added groups than that of the control (P＜0.05). 0.15 mg•kg-1 Se (Se-Met) group significantly increased SelW mRNA relative expression compared to both control and SS groups (P＜0.05). 【Conclusion】 Compared with the same Se supplementation in the form of SS, Se-Met had greater absorption, deposition rate and antioxidant capacity in plasma and tissues.

Studies on SNP and Genomic Imprinting of the IGF2R Gene in Swine

LI Li,CHEN Yu-ming,BAI Ying-shan,WU Tong-shan,ZHANG Shou-quan

Scientia Agricultura Sinica. 2010, 43(10): 2156-2161 . doi:10.3864/j.issn.0578-1752.2010.10.023

Abstract ( 829 )

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【Objective】 In this study, single nucleotide polymorphism (SNP) was found in IGF2R exons and used as marker to investigate the imprinting pattern of IGF2R in swine. 【Method】 Gene polymorphism of swine IGF2R was detected from 243 pigs of three breeds by PCR-SSCP. Imprinting patterns of IFG2R exon 48 were analyzed in organs of three heterozygous piglets and one hog by RT-PCR-RFLP/SSCP. 【Result】 One SNP(a G→A transition) was identified in exon 48 of IGF2R , located at the 384th nucleotide (5→3),forming a Nsp I restriction site. Maternal expression of IGF2R exon 48 was observed in the main organs of four heterozygous pigs. 【Conclusion】 IGF2R exon 48 was maternally expressed and paternally imprinted in most tissues of piglets and hogs.

Levels of Endothelin, Calcitonin Gene Related Peptide and Some Cardiopulmonary Parameters in Miniature Pigs Anesthetized with a Miniature Pig Combination Anesthetic

LU De-zhang,FAN Hong-gang,HU Kui,MA Hai-kun,ZHANG Jian-tao,LI Jing,WANG Hong-bin

Scientia Agricultura Sinica. 2010, 43(10): 2162-2167 . doi:10.3864/j.issn.0578-1752.2010.10.024

Abstract ( 815 )

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【Objective】 The aim of this study was to investigate the effects of miniature pig combination anesthetic on the plasma ET, CGRP and some cardiopulmonary parameters in miniature pigs. 【Method】 Fourteen Chinese experimental miniature pigs were intramuscularly injected miniature pigs combination anesthetic at 0.15 mL•kg-1, and blood samples were collected in 0, 5, 10, 30, 45, 60, 80, 100 and 120 min, and simultaneously noninvasive blood pressure and HR were monitored. Plasma ET and CGRP were determined by radioimmunoassay. 【Results】 Blood pressure and HR were significantly changed from 5 to 10 min and at 80 min (P＜0.01 or P＜0.05). ET was changed similar to that of blood pressure, and the correlation between them was found (P＜0.05),and a negative correlation was observed between the CGRP and blood pressure (P＜0.05). 【Conclusion】 ET and CGRP participated in change of blood pressure which was caused by miniature pigs combination anesthetic, and ET and CGRP maybe the main reasons of change of blood pressure, which was caused by miniature pigs combination anesthetic.

The Pharmacokinetics and Bioavailability of Injectable Tiamulin Suspension in Pigs

HUANG He-xian ,ZENG Zhen-ling,HUANG Xian-hui

Scientia Agricultura Sinica. 2010, 43(10): 2168-2173 . doi:10.3864/j.issn.0578-1752.2010.10.025

Abstract ( 1326 )

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【Objective and method】 The pharmacokinetics and bioavailability of tiamulin were investigated and compared in 7 healthy pigs in a Latin square design following single intravenous (10 mg•kg-1 b.w), intramuscular (10 mg•kg-1 b.w) administration of tiamulin injection and single intramuscular (10 mg•kg-1 b.w) administration of tiamulin suspension. The tiamulin concentrations in plasma samples were determined by LC/APCI-MS. Roxithromycin was selected as internal standard. Pharmacokinetic analysis of plasma drug concentration-time data for tiamulin was carried out with a computer program 3P97. 【Result】 The tiamulin concentration-time data were fitted to a three-compartment open model after single intravenous administration of the tiamulin injection. The main pharmacokinetic parameters were as follows: t1/2β 2.04±0.23 h, t1/2α0.39±0.06 h, t1/2π0.12±0.04 h,Vd8.73±1.83 L•kg-1, AUC3.78±0.52 μg•mL-1•h-1,ClB2.99±0.43 L•kg-1•h-1.The tiamulin concentration-time data were described by a two-compartment open model with first-order absorption after single intramuscular administration of the tiamulin injection. The main pharmacokinetic prameters of the tiamulin injection were as follows: t1/2Ka 0.06±0.01h, t1/2β 3.67±0.41 h, Tmax 0.18±0.03 h, Cmax 1.32±0.25 μg•mL-1, AUC 2.62±0.21 μg•mL-1•h-1, and the bioavailability was 73.51%, respectively. For single intramuscular administration of the injectable tiamulin suspension, the tiamulin concentration-time data were described by a one-compartment open model with first-order absorption and the main pharmacokinetic parameter were as follows: t1/2Ka 0.04±0.01 h, t1/2Ke 2.90±0.43 h, Tmax 0.27±0.03 h, Cmax 0.7±0.11 μg•mL-1, AUC 2.80±0.35 μg•mL-1•h-1, and the bioavailability was 75.73%, respectively. The statistics t-test results showed that there were no significant differences in pharmacokinetics of tiamulin in pigs between two dosage forms except Cmax. 【Conclusion】 The results of present studies showed that the injectable tiamulin suspension demonstrated rapid absorption, extensive distribution and rapid elimination.

Screening an Attenuated Strain and Immunogenicity in Mice of a Bovine Mastitis Staphylococcus Aureus Mutant

HE Na,WANG Chang-fa,YANG Hong-jun,HE Hong-bin,YANG Shao-hua,WANG Li-qun,GAO Yun-dong,ZHONG Ji-feng

Scientia Agricultura Sinica. 2010, 43(10): 2174-2181 . doi:10.3864/j.issn.0578-1752.2010.10.026

Abstract ( 1080 )

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【Objective】 The objective of the study was to screen an attenuated strain and immunogenicity in mice of a bovine mastitis Staphylococcus aureus mutant. 【Method】 An attenuated mutant, designated Hx, was derived from Staphylococcus aureus bovine mastitis strain SA zfb after N-methyl-N'-nitro-N-nitrosoguanidine mutagenesis. The characteristics were tested and the protection experiments were carried out by intraperitoneal administration in mice and challenged with homologous and heterologous strains. 【Result】 Mutant Hx, which was isolated on the basis of hypotoxicity, showed diminished virulence in mice (LD50 of SA Hx: 10-1.83•mL-1, LD50 of SA zfb: 10-4.33•mL-1). Mutant Hx grew more slowly than its parental strain and showed decreased production of several exoproteins, such as a- and β-hemolysin, DNAse and coagulase. The production of its capsule was induced only under in vivo growth conditions. In homologous challenge, the LD50 of SA zfb in mice immunized with different doses of the mutant was about 6 to 50 times higher than that of untreated mice. In heterologous challenge, the LD50 of SA 25923 and the LD50 of SA L20-2 in mice immunized with different doses of the mutant was about 5 and 60 times higher than that of untreated mice. 【Conclusion】 The fact shows that mutant Hx is attenuated and that it confered in mice immunity against homologous and heterologous strains, so it is an interesting candidate for the preparation of a live-attenuated vaccine against staphylococcal infections.

Discriminant Analysis of the Grades of Ham Sausages Based on Hardness, Fracturability and Adhesiveness Properties

HAO Hong-tao,ZHAO Gai-ming,LIU Yan-xia,LI Miao-yun,ZHAO Guang-hui,FENG Kun

Scientia Agricultura Sinica. 2010, 43(10): 2182-2188 . doi:10.3864/j.issn.0578-1752.2010.10.027

Abstract ( 846 )

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【Objective】 The possibility of the application of texture profile analysis in distinguishing the grades of ham sausages replacing sensory evaluation was discussed. 【Method】 The hardness, fracturability and adhesiveness of ham sausages of different grades were measured using sensory evaluation and instrumental measurement (texture profile analysis, TPA), and the capability of discriminating the grades of ham sausages by using discriminat functions established on data of the fracturability and adhesiveness was studied. 【Result】 The results showed that the discriminant accuracies of the established discriminant functions by hardness,fracturability and adhesiveness were 92.2% and 100.0%, respectively. The Fisher linear functions of premium, excellent and general class ham sausages founded were Y1=6.548 X1+ 3.498 X2+ 7.525 X3-68.989, Y2=4.608 X1+ 2.652 X2+ 6.457 X3-44.049, Y3=3.162 X1+ 1.392 X2+ 3.459 X3-15.176, respectively, based on sensory evaluation of hardness, fracturability and adhesiveness, and the Fisher linear functions based on hardness, fracturability and adhesiveness values were Y1=1.009 X4-0.255 X5-10.866 X6-3377.048, Y2=0.867 X4-0.233 X5-9.026 X6-2671.609, Y3=0.976 X4-0.244 X5-10.799 X6-3582.754. The grade distinguished as follows: the texture characteristics of sample were put into the functions , the grade was determined by the Y value,the biggest value represented the grade of sample. 【Conclusion】 It is suggested that the current sensory evaluation methods could be replaced by instrumental measurement in distinguishing the grades of ham sausages, when considered physical properties only.

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