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Table of Content

    15 March 2011, Volume 44 Issue 6
    CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    The Constructure and Enzymatic Characterization of Isoamylase-Oligomer from Wheat Endosperm

    Scientia Agricultura Sinica. 2011, 44(6):  1077-1084 . 
    Abstract ( 713 )   PDF (584KB) ( 1007 )   Save
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    【Objective】Isoamylases are debranching enzymes that hydrolyze α-1, 6 linkages in α-1, 4/α-1, 6-linked glucan polymers. In plants, they have been shown to be required for the normal synthesis of amylopectin, although the precise manner in which they influence starch synthesis is still debated. 【Method】The isoamylase-oligomer were fractionated by salting out with ammonium sulphate, DEAE-cellulose column chromatograthy, and gel filtration using sephadex G-200. The constructure and component of ISA complexes were studied by using native polyacrylamide gel electrophoresis (Native-PAGE) and SDS polyacrylamide gel electrophoresis (SDS-PAGE). 【Result】 Results of the study showed that there are two distinct polymeric forms of isoamylase (ISA) in wheat endosperm: Presumably a homo-tetramer of ISA1 and a hetero-oligomer composed of four ISA1 and one ISA2. The molecular sizes of the homo- and hetero-oligomers were approximately 320 and 380 kD, respectively. The ISA1 homo-oligomer optimum temperature was 30℃, after 10 min 40℃ treatment, the activity was completely lost, while the optimum temperature of ISA1/ISA2 heter-oligomer was 35℃, which was active even when incubated at 50℃ for 10 min. Native-PAGE showed that ISA2 not existed separate activity,but when the ISA1 homo-oligomer was incubated with the ISA2, it had the same bands as ISA1/ISA2 hetro-oligomer, indicating that ISA1 and ISA2 combined to form a hetero-oligomer. 【Conclusion】Two multimeric forms of ISA are present in wheat endosperm. The hetero-oligomer was found to be more stable at high temperatures of 40℃ and 50℃. These results indicate that ISA2 plays an important role in amylopectin biosynthesis by enhancing the activity of the ISA1 homo-oligomer and facilitating the binding of the hetero-oligomer to polyglucan substrates.

    Chromosomal Constitution and Karyotype of Intergeneric F1 Hybrids Between Saccharum spp. and Erianthus fulvus Based on GISH
    Scientia Agricultura Sinica. 2011, 44(6):  1085-1091 . 
    Abstract ( 823 )   PDF (1354KB) ( 903 )   Save
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    【Objective】The objective of current experiment was to study the chromosomal constitution and karyotype of F1 hybrids that derived from sexual cross between cultivated sugarcane (Saccharum spp.) and Erianthus fulvus.【Method】Both monocolor and bicolor GISH (Genomic in situ hybridization) were performed using digoxigenin-labeled E. fulvus DNA and biotin-labeled female parental DNA as probes, the karyotypes of 3 hybrids were analyzed based on the result of GISHs. 【Result】 The results of GISHs revealed the transmission of 7 to 10 E. fulvus chromosomes into progenies. The chromosomes of E. fulvus were broken because of the female parents prevented alien genetic materials from introgressing during distant hybridization and resulted in elimination and fragmentation of E. fulvus chromosomes. The GISH result on nuclear of progeny showed the chromatins came from male and female parent are not intermixed and stays at different regions. The karyotype formulas of 3 hybrids were 2n=92=80m (4SAT)+12sm. 2n=88=82m+6sm and 2n=88=78m(2SAT)+10sm,and their karyotypes were 2C, 2C and 2B, respectively. 【Conclusion】Chromosomal constitution of F1 hybrids that derived from sexual cross between cultivated sugarcane (Saccharum spp.) and E. fulvus were n+n and 2n+n. The results of karpotype analysis showed that the chromosomes of these three progenies are primitive.

    Construction of a Normalized Full-Length cDNA Library of Banana Roots and Expression Patterns of Defense Genes
    Scientia Agricultura Sinica. 2011, 44(6):  1092-1099 . 
    Abstract ( 960 )   PDF (716KB) ( 779 )   Save
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    【Objective】The research purpose is to figure out the expression patterns of defense genes, screen candidate genes related to resistance to Fusarium wilt, and further clarify the resistance mechanism. 【Method】A normalized cDNA enriched in full-length sequences was constructed from roots of banana cultivar Nongke No. 1 inoculated with FOC race 4 using DSN (duplex-specific nuclease) normalization method combined with SMART (switching mechanism at 5′ end of the RNA transcript) technique. Furthermore, the expressions of defense genes were considered with multiplex semi-quantitative PCR. 【Result】The liter of original cDNA library was 3.1×106 cfu•mL-1, and amplified library was 2.8×108 cfu•mL-1. Then, 421 unigenes containing 42% unknown genes from the sequenced results of 580 clones selected randomly were obtained after the removal of low-quality sequences. The average size of cDNA inserts ranged from 750 to 3 000 bp with a recombination rate of 100%. The rate of full-length gene was 68%. Some protein genes associated with defense were obtained on the basis of cDNA library. By RT-PCR analysis, the expression levels of phenylalanine ammonialyase (PAL), catalase (CAT), β-1,3-glucanase (PR-2) and pectin acetylesterase (PAE) in non-inoculated condition were very low. However, seven defense genes were obviously increased after inoculated by FOC race 4, and peroxidase (POX), endochitinase (PR-3), PAE and PAL reached the peak in the sixth day. Though the expression patterns of seven defense genes were similar with the controls, the intensities were much less than the inoculations. 【Conclusion】 These results indicated that the normalized full-length cDNA library was established successfully, which can be used for isolating required gene in the light of the rate of recombinant and integrity. Meanwhile, seven defense genes were identified, which played a key role in resistance to Fusarium wilt in some extent.

    TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY·AGRICULTURE INFORMATION TECHNOLOGY
    Effects of Elevated Ozone Concentration on Grain Yield and Plumpness in Wheat with FACE System
    Scientia Agricultura Sinica. 2011, 44(6):  1100-1108 . 
    Abstract ( 819 )   PDF (372KB) ( 618 )   Save
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    【Objective】In recent years, tropospheric (ground level) ozone concentration was growing year by year because of the development of agriculture and industry, and had generated a degree of damage on crop production. 【Method】The effects of elevated ozone concentration (O3) on grain yield and its components and grain plumpness in five varieties of winter wheat (Tritcium aestivum L.) with a FACE (Free-Air Controlled Environment) system were studied in 2007-2009. The main-plot treatment had two levels of (O3): ambient level (A-O3) and 50% higher than ambient level (E-O3), and the sub-plot treatment had five typical varieties: Yannong 19, Yangmai 16, Jiaxin 002, Yangmai 15 and Yangfumai 2. The ozone treatment was imposed upon for the period from 5 March to 26 May in 2008 and from 6 March to 24 May in 2009, respectively. 【Result】 The O3 elevation decreased grain yield and its components (grain weight and numbers) significantly or very significantly. Under E-O3, the average grain yield was decreased by 19.74% (10.06%-34.53%) in two years, and 1000-grain-weight decreased by 17.88% (10.16%-29.47%), grain number per ear decreased by 3.47% (-1.53%-11.90%), but ear number increased by 0.95% (-14.58%-23.74% ) in different varieties, respectively. There was a significant or very significant difference among treatments, cultivars and years. The O3 elevation affected the development process of wheat grains, the grain length, width and thickness were decreased by 0%-4.16%, 7.95%-20.24% and 2.66%-11.00% under E-O3 condition, which led to the decrease of grain volume by 8.5%-31.5%. The O3 elevation affected grain filling process, the average grain filling rate decreased. Because of the changes of grain volume and grain weight, grain plumpness degree changed by -21.40%-3.76%, the grain shrinkage index increased by 0.23%-36.66%, respectively. 【Conclusion】 Under E-O3, grain yield decrease resulted mainly from the declining of grain weight which was caused by the decrease of grain filling rate and grain plumpness.

    Flower Induction and Utilization of Zea luxurians in Maize Breeding

    Scientia Agricultura Sinica. 2011, 44(6):  1109-1116 . 
    Abstract ( 1090 )   PDF (342KB) ( 958 )   Save
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    【Objective】 Zea luxurians is a short-day plant, which can’t reproduce in temperate regions. The objective of this study is to induce Zea luxurians flower by changing photoperiod, therefore to eliminate flowering time difference to cross it with elite maize cultivars and to create novel maize germplasm resources. 【Method】Using normal light condition as a control, the effects of different short-day treatments on the development of Zea luxurians were checked, the activity of peroxidases (POD) was measured and POD isoenzyme patterns were characterized. Then, flowering Zea luxurians was successfully crossed with common maize inbred lines. 【Result】The results showed that the critical productive induction stage in Zea luxurians was between 19 d and 26 d at seedling age. The induction rate was higher when the Zea luxurians seedlings were older (from 5 d to 47 d). The optimal day-length for reproductive induction was 9 hours. POD activity had certain correlation with the seedling age, but had no implication on the growth conditions. Four types of POD isoenzymes, i.e. a, b, c and d, were good characteristics for vegetative growth, and the POD isoenzymes of e, f, g featured reproductive growth. Furthermore, the composition of these POD isoenzymes determines whether Zea luxurians. entered into reproductive growth.【Conclusion】 In northern China, the flowering time of Zea luxurians can be synchronized with elite maize cultivars through short-day treatment, thus facilitates the distant hybridization and makes it possible to transfer novel genes into elite inbred lines to create new maize germplasms.

    Characteristics of Dry Matter Accumulation, Nutrients Uptake and Distribution in Hybrid Cotton
    Scientia Agricultura Sinica. 2011, 44(6):  1117-1124 . 
    Abstract ( 789 )   PDF (229KB) ( 675 )   Save
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    【Objective】 Dry matter accumulation and nutrients uptake were characterized in hybrid cotton (Gossypium hirsutum L.) cultivars, which provided theoretical basis in making measures for high yield fertilization according to cotton growth and development characteristics.【Method】 Biaoza A1 and Xinluzao 43, with the conventional cultivar Xinluzao 13 as control, randomized block design was made under field conditions and routine analysis of dry matter, nitrogen, phosphorus and potassium was done at laboratory.【Result】The quantities of dry matter accumulated and nitrogen, phosphorus, potassium uptake by the two hybrid cultivars (Biaoza A1 and Xinluzao 43) were increased by 20.6% and 15.5%, 16.1% and 10.5%, 16.4% and 11.4%, 21.0% and 18.5%, respectively, as compared with the control. The amounts of dry matter accumulated and nitrogen, phosphorus, potassium uptake by buds, flowers and bolls of the two hybrid cultivars were increased by 20.7% and 15.4%,16.9% and 10.7%, 18.1% and 11.5%, 20.7% and 18.3%, respectively, compared with the control. Higher amounts of dry matter and nutrients were consistently distributed in the leaves of hybrid cultivars, and were also recorded in the stems at the first and middle periods, and in the buds, flowers and bolls at the late stages as compared with the conventional cultivar (control). In the late growing period the nutrients uptake rate in stems and leaves of hybrid cultivars was lower than the conventional cotton cultivar, but the nutrients uptake rate in buds, flowers and bolls was higher in hybrid cotton than in the conventional cotton. 【Conclusion】 The amounts of dry matter accumulation and nutrients uptake in the two hybrid varieties used were significantly higher than those in the conventional variety. The whole uptake of N, P2O5 and K2O in Biaoza A1 and Xinluzao 43 were 302.7 and 288.1 kg•hm-2, 138.2 and 132.3 kg•hm-2, and 459.2 and 449.7 kg•hm-2, respectively.

    PLANT PROTECTION

    The Intraspecific Genetic Diversity of Pathogenic Fungi of Apple Ring Rot

    Scientia Agricultura Sinica. 2011, 44(6):  1125-1135 . 
    Abstract ( 951 )   PDF (613KB) ( 647 )   Save
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    【Objective】The objective of the study is to analyze the genetic diversity and find the preponderant populations of Botryosphaeria berengeriana isolates, the causal agents of ring rot disease of apple.【Method】Sixty-four isolates were identified by their morphologic characteristics in culture and their pathogenicity tests. Isolates were identified by their ITS rDNA sequence. Inter-simple sequence repeat (ISSR) analysis was used to investigate the genetic diversity of its isolates.【Result】Sixty-four isolates were identified as B. berengeriana by morphologic characteristics in culture and pathogenicity tests. The data of the ITS rDNA from selected 17 isolates accord with data of B. berengerian and separated into two haplotypes H1 and H2. The 13 functional ISSR primers generated 88 polymorphic bands within a total of 121 bands and revealed 72% polymorphism and could differentiate all 64 isolates. Their genetic similarities were from 0.44 to 0.99. Two groups of 64 isolates were identified based on their ISSR. Group 1 contains 21 isolates, while group 2 consists of 43 isolates.【Conclusion】In this study, it was found that the genetic diversity of B. berengeriana isolates were not correlated to their regions , symptoms and tissues of trees. Sixty-four isolates were separated into two ISSR groups, and group 2 predominated over group 1 in orchards .

    The Predation Function Response and Predatory Behavior Observation of Chrysopa pallens Larva to Bemisia tabaci
    Scientia Agricultura Sinica. 2011, 44(6):  1136-1145 . 
    Abstract ( 702 )   PDF (439KB) ( 907 )   Save
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    【Objective】 The objective of this study is to evaluate the potential regulation capacity of Chrysopa pallens to Bemisia tabaci, and analyze the function response, searching rate and relative predatory behaviors of C. pallens on B. tabaci egg, nymph and pupa in lab conditions.【Method】 Different prey densities of egg, nymph and pupa of B. tabaci were set up as different treatments for evaluating predatory capacity of 3rd instar larva C. pallens. The net aggregation of prey consumed and prey consumed ratio in each density were recorded and analyzed. Furthermore, the predatory period was classified into different independent behavior events and evaluated each event in the way of occurrence frequency and ratio of each behavior event to the total duration of predation. The description of each event was also executed at the same time. 【Result】 The results showed that the function response of C. pallens 3rd instar larva on B. tabaci egg, nymph and pupa were fitted to Holling II & III formulas. In lab controlled conditions, the predatory capacities of C. pallens on B. tabaci egg, nymph and pupa increased with the increasing prey density. The instantaneous attacking rate was increased with the increasing of target development stages, and the variation of dealing duration was nymph > pupae > egg. On the contrast, the best searching density was the lowest in nymph treatment. Furthermore, the evaluation of searching rate showed that the searching rate of C. pallens on B. tabaci increased with the increasing of target development stages. When C. pallens preyed egg and nymph, the percentage of walking and searching behavior were the most and second. But in pupa treatment, the searching behaviour was the first place and the predation was the second. Similarly, the frequency of each behavior was shown significant differences in predation courses. 【Conclusion】The present study demonstrated that the predatory capacity of C. pallens larva to B. tabaci egg, nymph and pupa increased with prey density increasing without any density restriction. The analysis of occurrence frequency and time spend ratio of each behavior event showed significant differences when predator preyed different kinds of prey. The results showed that B. tabaci pupa is the favorite prey of C. pallens larva at low prey density level.
    Cloning,Expression and Promoter Analysis of ORF13 of Spodoptera litura multicapsid nucleopolyhedrovirus II (SpltMNPVII)
    Scientia Agricultura Sinica. 2011, 44(6):  1146-1153 . 
    Abstract ( 579 )   PDF (537KB) ( 526 )   Save
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    【Objective】The objective of this study is to research the structure and function of a newly found virus strain Spodoptera litura multicapsid nucleopolyhedrovirus II (SpltMNPVII) ORF13. 【Method】 In order to study the function of the ORF13, the primers were designed according to the sequence of SpltMNPVII genome. The promoter of ORF13 was amplified by PCR. The promoter activities analysis and the time course of mRNA transcription analysis were done. The fragment of the ORF13 was then cloned into the vector of pET28a(+) and expressed. The polyclonal antibody was prepared by using the purified fusion protein. Titration determination of anti-ORF13 antibody was evaluated by ELISA. 【Result】 Nucleotide sequence analysis demonstrated that this gene has a baculovirus late promoter motif ATAAG at -84 bp upstream of start codon, early promoter motif was not found in it. Both promoter activities analysis and the time course of mRNA transcription analysis of the ORF13 showed that ORF13 was transcripted in early stage as well as in late stage, which begin it’s transcription at 2 h post infection (hpi) and reached a peak at 18 hpi and then the transcription level was slightly decreased from 24 hpi. pET-28a-ORF13 fusion protein expressed in prokaryotic and purified polyclonal antibody was good specificity, with the titer of 1﹕3 200 or more. 【Conclusion】 SpltMNPV II ORF13 is a composition structure protein, which was expressed at both early and late stage. ORF13 encoding protein may be a membrane protein of BV, which should be a factor in BV infecting host cells. The polyclonal antibody can be used to further study the biological characteristics and functions of proteins.

    SOIL & FERTILIZER·WATER-SAVING IRRIGATION·AGROECOLOGY & ENVIRONMENT
    The Spatial Variability and Factor Analyses of Top Soil Texture on a County Scale
    Scientia Agricultura Sinica. 2011, 44(6):  1154-1164 . 
    Abstract ( 971 )   PDF (1173KB) ( 860 )   Save
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    【Objective】Taking Pinggu district as the research region, the paper studied spatial variability and explored mechanism of spatial variability of soil texture on a county scale by traditional statistics methods and geo-statistics.【Method】 The paper analyzed the relationship between different soil particle composition and some factors by the Least Significant Difference (LSD) according to the test results by Levine’s method. As soil textures are the composition data, they were transformed by SLR and then the spatial distribution of the particle composition was predicted by Ordinary Kriging.【Result】Mean values of soil particle composition of different elevation groups, parent material, and land use and water buffer groups had some differences, and the differences were more significant between elevation, parent material types and soil particle composition. Generally speaking, soil particles became finer gradually with the decrease of elevation. Soils developed from acid rock with high quartz content are coarser. Soil particles of vegetable plot were relatively finer. Sand content increased with distance increased from water. Results analyzed by geo-statistics showed that strong spatial autocorrelation of different soil particle compositions and spatial variability was caused by structural properties. Interpolation results showed that the overall trend characteristics of spatial distribution of different soil particle compositions are obvious. 【Conclusion】By using methods of combining statistical analysis and geostatistics, deterministic and stochastic of soil texture can be comprehensively and systematically reflected. Distributions of soil particles mainly were affected by natural factors, such as topography and parent material. After translated by SLR,the prediction results of soil texture met the requirements for composition data interpolation.

    Effects of Nanoscale Fe3O4 on Microbial Communities, Enzyme Activities and 2,4-D Degradation in Red Soil
    Scientia Agricultura Sinica. 2011, 44(6):  1165-1172 . 
    Abstract ( 688 )   PDF (495KB) ( 652 )   Save
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    【Objective】The effects of magnetic field on microbial communities and enzyme activities in red soil by nanoscale Fe3O4 were investigated, and the degradation of herbicide 2,4-D in red soil after nanoscale Fe3O4 treatment was also studied. The research will provide a basis for soil remediation by magnetic nanoparticles treatment. 【Method】 The red soil was treated by different dosages of nanoscale Fe3O4, then the microbial communities and enzyme activities were analyzed by dilution plate method and chemical assay, and the concentration of 2,4-D in soil was determined by high performance liquid chromatography (HPLC). 【Result】 The results indicated that the nanoscale Fe3O4 treatment had a positive effect on bacteria and actinomycetes, however, the fungi number was decreased by the same treatment. The effects of magnetic field on microbial communities increased with the dosage of nanoscale Fe3O4, and the microbial number reached the maximum at the dosage of 80 g•kg-1. Similarly, the nanoscale Fe3O4 could also improve the activities of amylase, urease, neutral phosphatase and catalase, but the effects of magnetic field on enzyme activities were different. The degradation rate of 2,4-D in red soil treated with the nanoscale Fe3O4 was significantly higher than that without treatment, and the 84% of 2,4-D could be degraded in 7 days.【Conclusion】The nanoscale Fe3O4 can improve the microbial communities and enzyme activities as well as the degradation of 2,4-D in red soil.

    HORTICULTURE
    Advances in Research of the Self-Incompatibility Genotypes (S-genotypes) in Apple

    Scientia Agricultura Sinica. 2011, 44(6):  1173-1183 . 
    Abstract ( 904 )   PDF (338KB) ( 938 )   Save
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    Apple (Malus domestica Borkh.) is a typical species in Rosaceae family that exhibits gametophytic self-incompatibility (GSI). In this paper, the research advance in the S-alleles (more than 30 S-genes) of apple was reviewed, PCR-based theoretical basis and methods for identifying the S-genotypes of apples were summarized, more than 500 S-genotypes of apples which were identified with various methods were enumerated, which would be valuable for selecting appropriate pollinated varieties and incompatibility parents for hybridization breeding.

    Limiting Ecological Factors Evaluation of High-Quality Apple at Wangdonggou Watershed in Loess Gully Region
    Scientia Agricultura Sinica. 2011, 44(6):  1184-1190 . 
    Abstract ( 778 )   PDF (399KB) ( 587 )   Save
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    【Objective】 Ecological factors have very important effects on apple qualities. So it is very important to find out the ecological factors limiting the quality of apple in apple production. 【Method】Taking Wangdonggou Watershed in Loess Gully Region as a case, the ecological factors of apple were evaluated by using principal component analysis and fuzzy comprehensive evaluation. 【Result】 In the study area, the ecological suitability was at the level of basically well, with the integrated ecological indices (IEI) being 0.74. It was also quantified that the Loess Gully Region is a good region for growing apple in China. Soil total nitrogen TN, organic matter (OM) and annual precipitation were the ecological factors limiting the quality of apple in Loess Gully Region, and their membership degrees were 0.34, 0.35, and 0.62, respectively. However, the annual mean temperature, the ≥10℃accumulated temperature, the mean temperature in mid-January, the daily range of temperature in summer, the available P and the available K all reached the extremely well level. 【Conclusion】According to the above results, a new way was raised for improvement of the quality of apple.

    Study on the Biomass and Regularity of Absorption and Utilization of Water and Nutrition in Euphorbia pulcherrima
    Scientia Agricultura Sinica. 2011, 44(6):  1191-1200 . 
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    【Objective】 The aim of this study was to reduce the production cost and improve the utilization rate of water and fertilizer, and to realize the precise control of potted flowers. 【Method】 The law of absorption and utilization of water and nutrition in different developmental stages of poinsettia was studied by equation regression. 【Result】 It was found that the change curves of water and nutrition uptake as well as the change curves of biomass accumulation in poinsettia showed S pattern. The determination coefficient of the models established by logistic regression equation y=1/(a+be-x) was higher than 0.99. The rate of biomass accumulation, as well as water production and nutrition absorption in poinsettia was right deviation bell-shaped.【Conclusion】The suitable watering frequency and fertilizer amount matching specified medium in different developmental stages of poinsettia were simulated. Watering when the medium water content was 65.09% during 31-53 days, 66.83% during 54-93 days, and 64.34% after 93th day, the water amount was 500.00 mL per pot. The fertilizer amount was 794.68-808.59 mg per pot during 31-58 days, 827.15-833.33 mg per pot during 59-107 days, 831.01-833.33 mg per pot after 107 days, once a week. These conclusions provided a technical support for low cost, high quality and efficient production of potted poinsettia with precise control of water and nutrition.

    Comparative Study on Heat Resistance of Lily Hybrids and Their Parents
    Scientia Agricultura Sinica. 2011, 44(6):  1201-1209 . 
    Abstract ( 728 )   PDF (562KB) ( 590 )   Save
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    【Objective】The aim of the test is to study the heat resistance of lily hybrids and their parents, to screen excellent breeding materials.【Method】The plantlets of lily hybrids from Lilium pumilum(provenance of Chengde)בSiberia’ and L.pumilum(provenance of Daqing)בSiberia’ as well as their parents were used as experimental materials and they treated at different temperatures (25℃, 28℃, 31℃, 34℃, 37℃, 40℃ ), and then the changing regularity of resistance physiological indices and the electrical impedance spectroscopy parameters were studied. 【Result】 Treatment at 31℃ promoted the chlorophyll content and root activity, hybrids were their parents or were better than parents in chlorophyll content and activity, and there was a significant correlation between the two indexes(P<0.01). At 37 ℃, the proline content of two hybrids reached the lowest(P<0.05), but still was higher than that of their parents. At 34 ℃, the relaxation time rose and the conductivity decreased significantly, the hybrids were better than male parents, the two indexes had a significant correlation (P<0.05). 【Conclusion】 The heat resistance of L. pumilum (provenance of Daqing) was higher than L. pumilum(provenance of Chengde), the heterosis of hybrid was significant when it was used as female parent. The heat resistance of hybrids was similar to their female parents, but was better than that of their male parents.

    STORAGE·FRESH-KEEPING·PROCESSING
    Establishment of the Detecting Method on the Fruit Texture of Dongzao by Puncture Test
    Scientia Agricultura Sinica. 2011, 44(6):  1210-1217 . 
    Abstract ( 1207 )   PDF (378KB) ( 878 )   Save
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    【Objective】The objective of this study is to enrich the evaluation index of the fruit quality of Chinese jujube, establish an identically standardized evaluating method for the fresh eating jujube and other fruits, and serve the production and research.【Method】In this paper, TA.XT plus texture analyser was used to perform the puncture test with the whole fruit of Dongzao. Through the texture detecting of Dongzao from different sources, the editing of the Macro program in the Texture Exponent 32 and the factor variance analysis of the outputing data, a suitable detecting method system of puncture test for Dongzao was established.【Result】The main method was: two points at the equatorial face of the fruit wall of a whole Dongzao fruit were selected to perform the experiment and more than 20 fruits were required to fulfill a sample test. The test conditions were listed as follows: a needle like probe (P/2n, diameter: 2 mm) was used to perform the puncture test, the speed before the test was 5 mm•s-1, the speed in the test was 1 mm•s-1, the speed after the test was 5 mm•s-1, the trigger force was 5 g, the threshold force was 2 g and the puncture distance should be less than the thickness of the flesh; After the enactment of the Macro program, the parameters could be received in the illustration curve as follows: pericarp break force (g), pericarp break distance (mm), pericarp brittleness (g•s-1), pericarp toughness (g×s), maximal flesh firmness (g), mean flesh firmness (g) and the number of peaks.【Conclusion】The detecting method could detect distinct texture of Dongzao with different water contents, storage periods or growing orchards accurately and expediently. In the same time, this method could also be applied in the texture detecting of other fresh eating jujube and other small fruits.

    Study on Antioxidative Activity of Maillard Reaction Products Derived from Jinhua Ham By-Products Hydrolysates
    Scientia Agricultura Sinica. 2011, 44(6):  1218-1223 . 
    Abstract ( 823 )   PDF (326KB) ( 674 )   Save
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    【Objective】The objective of this study was to analyze the composition of Jinhua ham by-products hydrolysates and evaluate the antioxidative activity of its Maillard reaction products (MRPs). 【Method】Amino acid composition and molecular weight distribution of the hydrolysates were determined by RP-HPLC and HPGFC, respectively. MRPs were prepared from the hydrolysates and glucose (xylose), the antioxidative activity was assessed in vitro. 【Result】The content of free amino acids and essential amino acids in the hydrolysates were 5.52% and 21.68%, respectively. The hydrolysates mainly contained the components with the molecular weight of 180-500 D. With the prolongation of the reaction time, the colour of the MRPs deepened, DPPH radical scavenging ability and reducing power showed the tendency of increasing as well. The reaction speed of the hydrolysates and xylose were faster relatively. DPPH radical scavenging ability and reducing power of MRPs derived from hydrolysates + xylose were significantly higher than that from hydrolysates + glucose at 90 min. 【Conclusion】 Jinhua ham by-products hydrolysates with high nutritive value were mainly composed of small peptides with 2-4 residues. Its MRPs were found to possess DPPH radical scavenging capacity and reducing power.

    ANIMAL SCIENCE·RESOURCE INSECT
    Study on Relationship Between Histone Acetylation and mRNA Expression Level of Histone Deacetylase of Porcine Early Parthenogenetic Embryos
    Scientia Agricultura Sinica. 2011, 44(6):  1224-1231 . 
    Abstract ( 964 )   PDF (429KB) ( 632 )   Save
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    【Objective】 The aims of this study were to investigate the relationship between the levels of histone acetylation (AcH4K5) and mRNA expression level of histone deacetylase 1(HDAC1) during early development of porcine parthenogenetic(PA) embryos in vitro. 【Method】 Porcine PA embryos (2-cell, 4-cell, morula and blastocyst) were collected, histone acetylation levels of AcH4K5 of four states’ embryos were assessed using immunofluorescence and laser confocal microscope by detecting the fluorescence intensity. Real-time PCR method was used for quantitative analysis of HDAC1 mRNA level in PA embryos. 【Result】The results showed that AcH4K5 expressed in nucleolus of all embryos from 2-cell to blastocyst, and the levels of AcH4K5 expression increased gradually, reached the highest in blastocyst stage, and the expression at each stage was different significantly(1124.77±127.78, 1305.81±184.23, 1795.19±318.67, and 2149.63±529.47, P<0.05, respectively). There were dynamic changes of HDAC1 mRNA level among four states’embryos (2-cell, 4-cell, morula and blastocyst of PA embryos), and mRNA expression patterns of HDAC1 genes decreased from 2-cell to blastocyst stage (1.00±0, 0.91±0.009, 0.85±0.008, 0.67±0.006, P<0.05, respectively). 【Conclusion】 These results indicated that there is an inverse correlation between the levels of AcH4K5 and mRNA expression of HDAC1 genes from 2-cell to blastocyst.

    Distribution of FSH Receptor on the Ovaries Among Different Sheep Breeds by Different Efficiency of Superovulation
    Scientia Agricultura Sinica. 2011, 44(6):  1232-1238 . 
    Abstract ( 893 )   PDF (477KB) ( 679 )   Save
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    【Objective】 This study was aimed to investigate the distribution of FSHR (FSH receptor) on the ovaries among different local breeds of sheep by different efficiency of superovulation, and to do some preparations for further improving this ovine propagation technique. 【Method】 Three local ovine breeds were selected depending on their different own sensitivity range to superovulation by FSH as following: Small Tailed Han sheep, White Tan sheep, and Ujumqin sheep. At 8, 16, and 24 hour after the last injection with FSH, the ovine ovaries were collected and treated by immunohistochemical staining to observe the distribution of FSHR on their different ovarian follicles.【Result】The results showed that FSHR was expressed mainly on granulosa cells. At 8, 16, and 24 hour after the last injection with FSH, the FSHR levels on the ovarian follicles of Small Tailed Han sheep, were significantly higher than those of the other two breeds, while the FSHR levels in early and middle ovarian follicle of White Tan sheep, were also higher than Ujumqin sheep(P<0.05). At 8, 16, and 24 hour after the last injection of FSH, the FSHR levels in the late ovarian follicle of those three breeds were significantly higher than those in the early and middle ovarian follicle(P<0.05). The results showed that the responsive orders to FSH treatment of these three different local ovine breeds be one by one as following: Small Tailed Han sheep>White Tan sheep>Ujumqin sheep.【Conclusion】It can be concluded that there is a relation between the effect of superovulation among different local sheep breeds and the distribution of FSH receptor on their ovaries.

    Relationship Between the Reproductive Ability of Hu Sheep and the Expression Level of Genes Correlated with Ovulation
    Scientia Agricultura Sinica. 2011, 44(6):  1239-1246 . 
    Abstract ( 676 )   PDF (633KB) ( 695 )   Save
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    【Objective】 The present study was performed to investigate the relationships between the mRNA level of COX2, HAS2, TSG6 and PTX3 in ovaries and the reproductive ability of Hu Sheep, so as to provide references for finding hyperprolificacy candidate genes and understanding the molecular genetic mechanism of high fecundity in Hu sheep. 【Method】Sixteen adult Hu ewes, classified as high-yielding (H) or low-yiebding group (L), were sacrificed for tissue sampling between 24-36h after estrus diagnosis. The tissue distributions of COX2, HAS2, TSG6 and PTX3 mRNA were detected by RT-PCR and the gene expression levels in the ovaries were investigated by real-time PCR. 【Result】COX2, HAS2, TSG6 and PTX3 all expressed in ovary of Hu sheep. The expression level of COX2 mRNA in the ovary did not differ between H and L group (P>0.05), but TSG6 and PTX3 mRNA abundance in the ovary was extremely higher in H group than that in L group (P<0.01). In addition, HAS2 mRNA abundance in the ovary was extremely higher in L group than that in H group (P<0.01). 【Conclusion】 The results suggested that HAS2, TSG6 and PTX3 might play a key role in reproductive ability of Hu Sheep and might be candidate genes for high fecundity in Hu sheep.

    Characteristics of Ascospheare apis Extracellular Proteinase
    Scientia Agricultura Sinica. 2011, 44(6):  1247-1254 . 
    Abstract ( 875 )   PDF (324KB) ( 817 )   Save
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    【Objcetive】 The objective of the study is to research the extracellular proteinase of Ascospheare apis which plays a key role for the pathogen to infect honeybee. 【Mehtod】 The extracellular enzyme of A. apis was induced, purified and concentrated from an artificial medium. Then different substrates were used to determine the activity of caseinase,azocaseinase,collagenase and elastase trypsin. 【Result】 The results showed that caseinase, azocaseinase and collagenase were secreted by A. apis. Moreover, the optimum reaction temperature of three extracellular pretenase was all around 40℃, the optimum pH was all around 7. They were stable in middle pH buffer system under low temperature but quickly lost their activity under high temperature. 【Conclusion】 Multiple extracellular proteinase could be secreted by A. apis. Their optimum temprature was around 40℃ and the optimum pH was around 7, which was coincident with the physiological parameter of bee larvae midgut.

    VETERINARY SCIENCE
    Research Progress on Analyses of Complete Mitochondrial Genomes for Nematodes
    Scientia Agricultura Sinica. 2011, 44(6):  1255-1265 . 
    Abstract ( 896 )   PDF (533KB) ( 1129 )   Save
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    Nematodes (roundworms) are abundant with a variety of lifestyles, and many of them such as Trichinella spiralis, Ascaris suum and Brugia malayi are parasitic and of veterinary and medical importance causing substantial socioeconomic losses across China and worldwide. The review focuses on current progress, applifications and perspectives related to mitochondrial (mt) genomes (mtDNAs) and genomics of nematodes. Until now, complete mt genomes for 46 species of nematodes have been sequenced and analyzed. The mt gene content, arrangement, composition, variation and so on of nematodes are unique and provide important data concerning functional and comparative mitochondrial genomics, molecular taxonomy, specific species characterization, population genetics and systematics, and evolutionary history. Moreover, they lay the foundation for mtDNA-based methods for diagnosis and epidemiology of nematodiasis.

    Experiment Study of Rutin on Mammary Gland Development in Ovariectomized Virgin Rats
    GUO Xu-dong,DIAO Qi-yu,WANG Yue-ying,TU Yan,YAN Gui-long,FU Tong,WANG Xin-jian, DENG Kai-dong,ZHANG Nai-feng,JU Cui-fang,LI Jun-tao,SONG Kai,GU Xiao-wei,LÜ,Zong-you,XU Jun
    Scientia Agricultura Sinica. 2011, 44(6):  1266-1276 . 
    Abstract ( 908 )   PDF (521KB) ( 660 )   Save
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    【Objective】 The objective of this study was to investigate the regulatory effect of rutin in promoting mammary gland develop’s estrogen-like effect by examining the effects of ovariectomized virgin rats levels of endocrine hormones, the expression of receptor and histomorphology of development.【Method】Thirty-two ovariectomized virgin rats were randomly assigned to four treatments: sham, gastric infusion of 2 ml normal saline per mouse and per day; Ovx, gastric infusion of 2 ml normal saline per mouse and per day; Ovx+Rut, gastric infusion of 60 mg rutin•kg-1BW per day; Ovx+Est, intramuscular injection of 60 µg estradiol•kg-1BW weekly. The trial lasted two weeks. The samples of blood, gland tissues were collected respectively. The level of estrogen (E2), prolactin (PRL) and growth hormone (GH) in plasma and gland tissues were dected by the use of Radioimmunoassy (RIA) technology; and the expression of estrogen receptor (ER), prolactin receptor (PRLR) and growth hormone receptor (GHR) in gland tissues were detected by the use of RT-PCR technology. Histomorphology of development about mammary gland were observed.【Result】The results showed that, the level of E2 in plasma and gland tissues was Ovx+Rut and Ovx+Est were highter than Ovx (P<0.05),and the difference between two groups was not significant (P> 0.05), Ovx+Rut was lower than Sham (P<0.05), Ovx+Est and Sham have no distinct (P>0.05). The level of E2 in gland tissues showed the same regularity. The order of the PRL in plasma and gland tissues was Ovx<Ovx+Rut<Ovx+Est<Sham (P<0.05). The levels of GH in plasma peresents Ovx, Ovx+Rut, Ovx+Est, Sham increased in turn (P<0.05). The GH In gland tissues, the levels of GH in Ovx was lower than in Ovx+Rut and Ovx+Est (P<0.05),and Ovx+Rut was lower than Sham(P<0.05). The difference between Ovx+Rut and Ovx+Est was not distinct(P>0.05), Ovx+Est and Sham’s differences were not distinct either (P>0.05). The expression of ER, PRLR, GHR in gland tissues in Ovx, Ovx+Rut, Ovx+Est and Sham increase in turn (P<0.05), and showed the same trend. The observation of histomorphology showed that the development of gland tissue in Ovx+Rut, Ovx+Est and Sham was better than in Ovx (P<0.05).【Conclusion】Rutin could improve the level of E2 in ovariectomized virgin rats, increase pituitary PRL and GH release, up-regulated the expression level of ER, PRLE and GHR .
    AGRICULTURAL ECONOMY & MANAGMENT
    Contract Production and Farmer’s Organic Fertilizer Use Behavior ——An Empirical Analysis Based on the Survey Data of Apple Growers in Shandong Province
    Scientia Agricultura Sinica. 2011, 44(6):  1277-1282 . 
    Abstract ( 670 )   PDF (245KB) ( 786 )   Save
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    【Objective】As the lacking application of organic fertilizer will exacerbate the soil nutrients imbalance and fertility decline and be a serious threat to sustainable agriculture and rural economic development as well, how to take effective measures to guide farmers to adjust their fertilization structure is a problem to be solved in the process of China’s agricultural development. The objective of the research is to study the impact of contract production on farmer’s organic fertilizing behalior. 【Method】 Using the survey data on apple growers in Shandong Province, this paper aims to evaluate the impact of contract production on organic fertilizer use behavior and the underlying mechanism.【Result】The analysis demonstrates that, marketing contract, production contract, orchard distance from house, orchard size, awareness of organic fertilizer and the proportion of non-agricultural income have a positive correlation with organic fertilizer application. Fertilizer application and the amount of labors have a negative correlation with organic fertilizer application.【Conclusion】When other conditions are the same, farmer signed marketing contract and production contract will increase organic fertilizer application by 678 yuan/hm2 and 1 497 yuan/hm2, respectively; orchard distance from house, orchard size, awareness of organic fertilizer, the amount of labors and the proportion of non-agricultural income are also important factors in farmer’s decision-making of organic fertilizer use.

    RESEARCH NOTES
    Difference of Endogenous Hormones in Young Spike Between Main Stem and Tillers and Its Effects Under Different Densities in Lankao Aizao 8
    Scientia Agricultura Sinica. 2011, 44(6):  1283-1291 . 
    Abstract ( 831 )   PDF (258KB) ( 578 )   Save
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    【Objective】The objectives of this study were to analyze the relationship between the endogeneous hormones of young spike and the senescence of the tillers, and to investigate the regulating effects of planting densities on the endogeneous hormones of young spike in Lankao Aizao 8 with large spike. 【Method】 The experiment was conducted with three density treatments respectively as 150(D1), 262.5(D2) and 375(D3) million basic seeding per hectare in 2007-2008. At the wheat jointing stage, labeled plants were selected to distinguish main stem, tiller Ⅰ and tiller Ⅱ during the young pinicle differentiation process. Young spikes were stored in liquid nitrogen. The contents of indoleacetic acid (IAA), gibberellins (GAs), abscisic acid (ABA), zeatin riboside (ZR) were determined using enzyme-linked immunosorbent assay (ELISA) method. 【Result】The difference of spike differentiation process between main culm and two tillers was small at florets initiation, and increased after then, which indicated that the young pinicle differentiation process in main culm was faster than that of two tillers. The content of GAs, IAA and ZR, the ratio of IAA/ABA and ZR/ABA in young spike appeared as main culm > tillersⅠ> tillers Ⅱ during tiller polarizing stage, but the content of ABA was contrary at late jointing stage, higher IAA/ZR had inhibition on tillers growth.【Conclusion】The higher content of GAs, IAA, ZR and ratio of IAA/ABA and ZR/ABA in young spike were beneficial to young spike growth, but higher content of ABA and ratio of IAA/ZR had opposing effect on tillers growth and young pinicle differentiation. The senescence stage of tillers was earilier, the difference of endogeneous hormones content was larger between main culm and tillers, and plant densities had significant regulating effects on endogeneous hormones and tillers decease.

    Optimization of EcoTILLING Technique in Barley
    Scientia Agricultura Sinica. 2011, 44(6):  1292-1300 . 
    Abstract ( 697 )   PDF (1151KB) ( 674 )   Save
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    【Objective】The goal of this work is to establish an optimized EcoTILLING protocol for identification of natural variations within target genes and specified regions of genomes in barley. 【Method】The universal adapter M13 was labeled with fluorescent dyes, the nested PCR with specific primer combination and M13 adapter was performed for the targeted region. The EcoTILLING protocol for barley was optimized, including the template amount and annealing temperature in PCR amplification, CELⅠamount and reaction time in cleavage of mispaired heteroduplex DNA. 【Result】The results showed that the optimal amount of genomic DNA in a 10 μL of reaction system was 20 ng as template for the first round of PCR, and the first PCR product was diluted 3-fold and used as a template for the second round. The proper annealing temperature for both first- and second-round PCRs was 58℃. Optimum amount of CELⅠ enzyme was 0.4 μL (3 U•μL-1) in a 20 μL of digestion reaction system, and 17.5 min at 45℃ was the optimal time for the cleavage of heteroduplex DNAs. 【Conclusion】The experiment indicates that the optimized EcoTILLING protocol can effectively detect DNA polymorphisms for natural population of barley with lower cost, and it could provide a foundation for larger scale efforts in reverse genetics and characterization of natural nucleotide variation in barley.

    Anatomical Structures of Oleocellosis of Navel Orange Peel
    Scientia Agricultura Sinica. 2011, 44(6):  1301-1306 . 
    Abstract ( 686 )   PDF (427KB) ( 658 )   Save
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    【Objective】The aim of the paper is to explore the anatomical structures and preventive measures of oleocellosis through researching the anatomical structure of two navel orange varieties from Chongqing’s Fengjie in different treatments and compare the effects of waxing or bagging on oleocellosis.【Method】 Plastics microtomy was used in this research through JB-4 permeating, embedding, and slicing with glass knife, double-staining by PAS-TBO, and peel cells and characteristics of organizational structure were observed and determined by microscope.【Result】No rupture was observed in oil cavities exist in the epicarp in the healthy or the early onset, but rupture was observed in late period in illness samples. The occurrence degree of oleocellosis related to the degree of uniformity of peel corneous layer rather than the thickness. Uniform texture, smooth appearance, good effect of retaining freshness, but waxing did not affect the occurrence of oleocellosis. Bagging lessened the chance of other disease infection, and the texture was uniform, the appearance was smooth, and the peel cuticle was more complete.【Conclusion】Strong light, external pressure, peel moisture and mechanical damage all could increase the probability of oleocellosis. Bagging may help to reduce the occurrence probability of oleocellosis.