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    10 July 2007, Volume 40 Issue 7
    CROP GENETICS & BREEDING·GERMPLASM RESOURCES
    Genetic Analysis of Giant Embryo Mutation in Indica Rice
    Scientia Agricultura Sinica. 2007, 40(7):  1309-1314 . 
    Abstract ( 1598 )   PDF (283KB) ( 1001 )   Save
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    Seeds of several indica rice cultivars were treated by nucleus irradiation and strains with giant embryo(ge) were selected in M2 and M3 generation. The inheritance of giant embryo character in rice was studied by investigating the size of embryo of plants in generations of P1、P2、F1、F2 and BC1F1, which were made by crossing the giant embryo mutants 98-14geB and Mge86 with their corresponding original types.The main results were as following: The giant embryo mutation frequency in M2 averaged 0.00125%, at range of 0.00029%-0.00285%. The giant embryo mutation frequency in M1 averaged 0.03015% or 0.03911%, depend on the different calculation methods. The ge mutants were detected in 9 M2 populations of 11 induced varieties. Mutation frequency varied with applied dosage and mutated materials. The trait of giant embryo is genetically controlled by a pair of recessive genes. The size of rice embryo is only controlled by the genotype of zygote, and not affected by the genotypes of the female parent plant and the cytoplasm. Hence, it is possible to identify giant embryo mutants directly from seeds of M2 or F2.. Population allelic tests shown that the gene in TgeB、1813geB、98-14geB and Mge86 are allelic to the ge gene of Japonica mutant “1137”.
    Construction of Expression Vector Harboring Pina&Pinb fused gene and its transformation into durum wheat
    Scientia Agricultura Sinica. 2007, 40(7):  1315-1323 . 
    Abstract ( 1595 )   PDF (572KB) ( 982 )   Save
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    Construction of expression vector is the basis of gene transformation, and a high frequency of callus induction and regeneration is crucial for successfully obtaining transplant. In the present study, a highly efficient expression vector (pFUPaPb) that harbors the fused fragment of Pina &Pinb flanked with regulation sequences of Ω and poly(A) was constructed, employing ubiqutin as a promoter and bar gene as a selective marker. Common wheat variety Jing 411 is the donor of Pina and Pinb genes. pFUPaPb was transferred into durum wheat by biolistic method. After screening with bialophos and PCR amplification with gene specific primers, 35 transplants were obtained, and the expression of fused genes was detected in 2 of 16 transplants examined. Results indicated that SD2 is the comparatively efficient medium for callus induction of durum immature embryo, and MS+8 mg.L-1 zeatin is good for callus regeneration. The results provide a high expression vector for wheat grain harness modification, and useful information for understanding the functions of Pina and Pinb genes.
    Genetic diversity revealed by chloroplast genome microsatellite markers in hexaploid wheat, wild emmer and Aegilops tauschii
    XinQuan Yang Xing Song JinKun Du ZhongFu Ni
    Scientia Agricultura Sinica. 2007, 40(7):  1324-1330 . 
    Abstract ( 1628 )   PDF (307KB) ( 968 )   Save
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    In this study, 21 SSR markers derived from chloroplast genome of common wheat, are used to measure the genetic diversity among hexaploid wheat populations and their relatives, which include 20 common wheat (Triticum aestivum L.), 21 spelt (Triticum spelta L.), 20 compactum (Triticum compactum Host.), 10 wild emmer (Triticum dicoccoides), 16 Chinese wheat landraces(9 T. tibetanum, 3 T. yunnanense and 4 T. petropavlavskyi) and 9 Aegilops tauschii. Compared with common wheat, the genetic variation base of chloroplast genome in spelt and T. tibetanum were more abundant, which can be used to broaden the genetic basis of common wheat. Cluster analysis exhibited that, wild emmer has a closer consanguine relationship to hexaploid wheat, as compare to with Aegilops tauschi. In addition, it was found that there was a closer genetic relationship in chloroplast genome of common wheat and T. petropavlavskyi, which indicated that T. petropavlavskyi maybe derived from the backcross between common wheat and Polish wheat.
    Construction of Full-length cDNA Libraries from Root and Shoot of Ae.tauschii and EST Annotation and Comparative Analysis
    GuangYao Zhao
    Scientia Agricultura Sinica. 2007, 40(7):  1331-1336 . 
    Abstract ( 1434 )   PDF (366KB) ( 1058 )   Save
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    Abstract: Expressed sequenced tags (EST) and full-length cDNA were important tool and resources for biological functional genomic and genetic research., the progenitor for D genome of bread wheat, was an important material for wheat genetic and genomic research.. Two full-length cDNA libraries were constructed from shoot and root of Aegilops tauschii Y2282 respectively by use of Cap-trapper method and 6616 ESTs and 6973 ESTs were obtained from the 2 libraries respectively. By use of our bioinformatic analysis platform base on Linux system , we did electronic annotation for the EST, including blasting against public database such as protein ,nucleotide and triticum and Aegilops EST databases from NCBI. By use of result of GO ontology catalogue ,which was obtained from software GoPipee, and expression profile ,which were come from Phrap assembling result, some EST differently or specifically expressed in 2 cDNA libraries were obtained. Maybe the results could help us understand the molecular basis of different functions which organs perform.
    Cloning and Expression Analysis of A Brassinosteroid Biosynthetic Enzyme Gene, GhDWF1, from Cotton (Gossypium hirsuturm L.)
    Scientia Agricultura Sinica. 2007, 40(7):  1337-1344 . 
    Abstract ( 1349 )   PDF (1283KB) ( 904 )   Save
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    Brassinosteroids (BRs) are an important class of plant steroidal hormones that are essential in a wide variety of physiological processes, including cell division and elongation, vascular differentiation, reproductive development, senescence, biotic and abiotic tolerance. To determine the effects of BRs on development of cotton fibers, we have cloned a key gene (GhDWF1) involved in the upstream biosynthetic pathway of BRs from developing fibers of upland cotton (Gossypium hirsutum L.) cv. XuZhou142. The full length of the cloned cDNA is 1849bp, including a 37bp 5’-untranslated region, an ORF of 1692bp and a 120bp 3’-untranslated region. The cDNA encodes a polypeptide of 563 amino acid residues with a predicted molecular mass of 65 KD. The deduced amino acid sequence has high homology with the BR biosynthetic enzyme, DWARF1/DIMINUTO, from rice, maize, pea, tomato and Arabidopsis. Furthermore, the typical conserved structure, such as the transmembrane domain, the FAD-dependent oxidase domain and FAD-binding site, are present in GhDWF1 protein. Southern blot indicated the GhDWF1 gene has a single copy in upland cotton genome. RT-PCR analysis revealed that the highest level of GhDWF1 expression was detected in 0DPA ovule (with fibers) while the lowest level was observed in cotyledon. The GhDWF1 gene expressed highly in roots, young stems and fibers. Moreover, the expression level was higher in ovules (with fibers) of wildtype (XuZhou142) than in ovules of fuzzless-lintless mutant at the same developmental stages (0DPA and 4DPA). Results suggest that the GhDWF1 gene plays a crucial role in fiber development, especially, in the initiation and the secondary cell wall deposition of fiber cells.
    TILLAGE & CULTIVATION·PHYSIOLOGY & ECOLOGY
    Effects of High Temperature on the Physiological and Biochemical Characteristics in Flag Leaves of Rice at Heading and Flowering Period
    Scientia Agricultura Sinica. 2007, 40(7):  1345-1352 . 
    Abstract ( 1273 )   PDF (583KB) ( 1312 )   Save
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    【Objective】To ascertain the physiological reaction and mechanism of adaption to high temperature stress of functional leaves in rice.【Method】For seven day,a study was conducted to determine the effects of high temperature stress(8:00-17:00,37℃,17:00-8:00,30℃)on the chlorophyll content,photosynthetic characteristics,heat stable protein content and membrane permeability of flag leaves in hybrid rice in controlled environment chamber.【Result】The results showed that chlorophyll content and chlorophyll a/b of flag leaves in rice decreased under high temperature stress,increased after high temperature stress,chlorophyll content of high-temperature tolerant cultivar 996 was greater than that of high-temperature sensitive cultivar 4628.The net photosynthetic rate and stomatal conductance of flag leaves declined and substomatal CO2 concentration and transpiration rate of flag leaves increased under high temperature stress,compared with high-temperature sensitive cultivar 4628,high-temperature tolerant cultivar 996 could keep higher photosynthetic characteristics under high temperature stress;Souble sugar and souble protein and free proline content of flag leaves decreased under high temperature stress,but heat stable protein content increased;The increase scope of malonyldialdehyde(MDA)content and membrane permeability in high-temperature sensitive cultivar 4628 was greater under high temperature stress than in high-temperature tolerant cultivar 996.【Conclusion】Under high temperature stress,higher photosynthetic characteristics and chlorophyll content,souble sugar,souble protein,proline,heat stable protein content and lower membrane permeability and MDA content of flag leaves in rice were the physiological basis of high-temperature tolerant cultivar.
    Effects of Leaf Removal on Yield Components in Different Spike-type Wheat Varieties
    Wandai Liu
    Scientia Agricultura Sinica. 2007, 40(7):  1353-1360 . 
    Abstract ( 1410 )   PDF (302KB) ( 988 )   Save
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    In order to ascertain the contribution of leaves in different spike-type wheat varieties to grain yield in high-yield condition, two spike-type wheat varieties were selected as experimental materials, effects of leaf removal at heading date on the photosynthetic rate of remnant leaves, node dry weight and setting kernels and grain weight in different spike-type wheat varieties were studied. The results showed that the photosynthetic rate of remnant leaves raised owing to leaf removal and the photosynthetic rate of remnant leaves in multi-spike cultivar-YM49 increased more evidently. The node dry weight in large-spike cultivar-S2001 lightened significantly after leaf removal. But all of these could not compensate the loss caused by leaf removal,final results were that both setting kernels and grain weight decreased. With the increment of leaves removed and the rise of leaf- position,setting kernels and grain weight decreased evidently. Effects of leaf removal at heading stage on yield components of YM49 were more than that of S2001. Therefore it is more important for realizing high yield in multiple spike-type wheat variety to safeguard canopy leaves by taking effective measures.
    Response on Water Stress and Low Nitrogen in Different Maize Hybrid Varieties and Evaluation for their Adversity-resistance
    Wei-Xing ZHANG
    Scientia Agricultura Sinica. 2007, 40(7):  1361-1370 . 
    Abstract ( 1275 )   PDF (412KB) ( 1072 )   Save
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    【Objective】With study on response and effect of water stress and low nitrogen on maize hybrid varieties, in order to make sure the drought-resistance and barren-tolerance of different hybrid varieties, which can contribute some gist for choosing maize varieties in arid, subarid and barren soil area.【Method】Seventeen maize hybrid varieties cultivated in fields and experimental design of different water stress and low nitrogen, the response and effect of water stress and low nitrogen on growth and development, yield and its components of these varieties were studied. Furthermore, the integrated evaluation for their drought-resistance and barren-tolerance based on adversity resistance index(ARI) of yield and cluster analysis of different maize hybrid varieties choosing eight traits closely correlated to adversity-resistance were carried out.【Results】The results showed that the yield of maize hybrid varieties under water stress and low nitrogen declined obviously comparing with contrast, which mostly were caused by number of grain per spike reduced less, grain weight descended lighter, spike became shorter and smaller, barren ear tip increased more, anthesis and silking interval(ASI) delayed. The response and effect on growth and development, yield and its components in maize of WNT treatment were more than NT treatment and WT treatment. To supply nitrogen under water stress or water under low nitrogen can lead to increase yield obviously, the interaction between water and nitrogen was fearfully significant and certain extent complex, and also correlated to maize varieties. The yield difference between water stress and normal water, low nitrogen and normal nitrogen, or among these varieties were significant at 0.01 level. The correlations between average ARI and yields under stress condition were also significant at 0.01 level, and there were relatively close affinities between adversity resistance index and yield, number of grain per row, 1000-grain weight, barren ear tip, length and diameter of spike, and ASI under different water stress and low nitrogen. Based on comprehensive evaluation and cluster analysis, the drought-resistance and barren-tolerance of Qian 2599, Qianyu 3 and Zhongdan 2 were best, secondly, Xinghuangdan 89-2, Qian 2411, Zunyu 3, Guibi 302 and Guibi 303 also showed better, however, Andan 136, Qianyu 1 and Qianxing 4 were worst.【Conclusion】The response and effect of low nitrogen on maize were more sensitive than which of water stress, and sensitivities of different hybrid varieties to water stress and low nitrogen were obviously different because of the diversity of drought-resistance and barren-tolerance. It is reasonable to evaluate synthetically the adversity-resistance with ARI in maize.
    Influences of Soil Bulk Density in Deeep Soil Layers on the Absorption and Redistribution of Nitrogen,Phosophrous and Potassium in Maize(zea mays L.)
    Scientia Agricultura Sinica. 2007, 40(7):  1371-1378 . 
    Abstract ( 1473 )   PDF (399KB) ( 1161 )   Save
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    Abstract:The study was carried out using pool cultivation under field exposure to indicate the influences of soil bulk density in deep soil layers on the absorption and redistribution of nitrogen,phosophrous and potassium in maize.The soil structure was made of 3 differernt soil layers,0-20cm,20-40cm and 40-60cm with different soil BD(bulk density).The main results showed that soil BD had a great effect on the absorption of N,P,K in maize, represented significantly in silking stage,and the order of this effect was K> P > N,The accumulation of N,P,K differed among the 5 treatments wtith the order T224>T244>T226>T246>T266,and this difference reached significant level.Soil BD also affected redistributive proportion and transferring rate of N,P,K in the different parts,especially in the centre growth, of corn plant in each stage,the redistributive proportion of N,P,K decreased with the increase of soil BD,and it always exhibited the highest proportion in T224 and the lowest in T266.Adjustment of soil BD in the deep soil layers can make the corn plant absorb more mineral nutrition,distribute more in the centre growth,and promote the growth of corn plant.
    Effects of Water Stress on Active Oxygen Generation and Protection System
    Scientia Agricultura Sinica. 2007, 40(7):  1379-1387 . 
    Abstract ( 1685 )   PDF (585KB) ( 1580 )   Save
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    Abstract:【Objective】Rice is one of the main staple food crops in the world, but rice may suffer serious water stress during its growth period. Water stress during grain filling results in decreasing grain yeild, but its mechanisms of Generating and scavenging active Oxygen is unclear under continuance of the water stress. 【Method】The experiments were carried out in growth chamber to investigate the effects of water stress on superoxide free radical content(O2—), hydrogen peroxide content(H2O2),MDA content, reduced glutathione content(GSH),ascorbic acid content (AsA)and antioxidative enzyme activities in three hybrid rice cultivars with different drought resistant abilities under both normal and drought conditions during grain filling stage. 【Result】The results indicated that water stress aggravated the membrane lipid peroxidation in rice leaves, and it was more severe in weaker drought resistant cultivars than that in better ones. O2— and H2O2 accumulated rapidly and were more rapidly in weaker ones than that in better drought resistant cultivars. During the period of water stress, decreases of GSH content,AsA content, chlorophyll content and relative water content in better drought resistant cultivars were obvious less than those in weaker ones. Activities of superoxide dismutase(SOD), catalase(CAT) and peroxidase(POD) in leave increased obviously in 0~14d after anthesis and subsequently decreased rapidly, and those in better drought resistant cultivars were more than those in weaker ones in 0~14d after anthesis. 【Conclusion】the results showed that changes of O2— content, H2O2 content,MDA content,GSH content,AsA content and antioxidative enzyme activities correlated significantly to drought resistance of rice varieties, and better drought resistant cultivars possesses high antioxidation capacity.
    PLANT PROTECTION
    Screening of the method in vitro for testing the effect of E26 against grape crown gall
    Jing Wang Yanbin Guo JinYun Li JianHui Wang HuiMin Wang
    Scientia Agricultura Sinica. 2007, 40(7):  1395-1402 . 
    Abstract ( 1446 )   PDF (495KB) ( 882 )   Save
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    Grape crown gall disease is a soil-borne bacterial disease caused by virulent strain of A.vitis. Biocontrol bacteria has been one of the efficient methods to control the disease. Evaluation of biocontrol effect is extremely important in screening of potential biocontrol agent. At present, the effect testing is performed by inoculating indicator plant or host plant in vivo. In this communication, we investigated the effect of E26 through inoculating grape stem and leaf in vitro. 1/2B5 medium was modified for better growth of grape stem in vitro culture, and the best methods of sterilization and inoculation were screened in this experiment. The stem in vitro test demonstrated the same effect when compared with the in vivo test, and could be the quick and accurate evaluation to indicate the effect of E26. While the grape leaf in vitro test could not accurately reflect the effect of E26, because crown galls formed only on leaf veins and were too small to be examined. The grape stem in vitro testing can be a promising method to detect the effect of E26.
    Oxidative Damage to Spodoptera litura Cell Induced by α-terthienyl
    Scientia Agricultura Sinica. 2007, 40(7):  1403-1409 . 
    Abstract ( 1199 )   PDF (978KB) ( 931 )   Save
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    【Objective】It’s important of surveying the oxidative damage and its mechanism to insect cell of induced by photosensitizer to speed its application. 【Method】MTT was used to acquire the toxicity of α-terthienyl (α-T) to Spodoptera litura cell. The output of malondialdehyde and relative content of glutathione were determined by 2-thiobarbituric acid and 5,5’-dithio-bis(2-nitrobenzoic aicd) respectively. Transmission electron microscope was employed to observe the influence of α-T to the membrane and organelle of SL cell. 【Results】The LC50 value of α-T to SL cell was 0.21μg/mL, whereas the dose of rotenone was 12.25μg/mL . The output of MDA had the same changing tendency with the concentration of α-T, whereas the content of GSH had the negative correlation with the concentration of α-T. According to TEM, cell membrane and karyotheca swelled and couldn’t retain integrity. The intracellular substances leaked out. The mitochondria expanded, the nuclear appeared pycnosis, the chromatin condensed. The biological membrane and subcellular organelle were damaged severely. 【Conclusion】After oxidative damage occurring, the output of MDA increased notably, whereas the relative content of GSH decreased. This indicated that the antioxidant ability of cell weakened. The result of TEM implied that SL cell suffered from oxidative damage under the appointed dose.
    Novel antibiotics——Studies on bioactivity of qinlingmycin and protoplast fusion of its producing strain
    Scientia Agricultura Sinica. 2007, 40(7):  1416-1421 . 
    Abstract ( 1122 )   PDF (320KB) ( 1017 )   Save
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    a novel lactam antibiotic, qinlingmycin, was isolated from fermentation products of one Streptomyces separated from the soil of qingling mountain. The bioactivity of qinlingmycin had been compared with Penicillin and Cephradine. the result showed that the inhibition activity of qinlingmycin against Bacillus cereus,Bacillus cirulans,Pleudomona aereuginosa were better than Penicillin and Cephradine. and the MIC was 1.2ug/ml,1.5 ug/ml and 2.0ug/ml respectively. against Sarcina Lutea Schroeter,Zscherichia coli was lower than Penicillin and Cephradine. The activity against Staphylococcus aureus is higher than Penicillin lower than Cephradine.No.24 and Ms-24 strain produce qinlingmycin but also pigment.No.24 and mutagensis Ms-24 strain’s protoplast were obtained in lysozyme.the protoplast were mixed at ratio of 1:1 with PEG was added to fuse protoplast.and marking the fusants with fluorescence.. qinlingmycin was obtained through isolation and purification.some relative conditions for preparation, fusion and regeneration of two strain’s protoplast were studied. it was proved that 0.25% Gly was optimal condition for preparation and regeneration of the protoplast. the lysozyme concentration was 1mg/ml,and the optimal treating time was 1h.PEG in different molecular weight tested in the experiment had little influence on fusion of the protoplasts. but its concentration was of importancel.PEG at a concentration on 50% was of benefit to the protoplast fusion. .among 163 fusants, strain, three highly qinlingmycin-producing strain pf77,pf126 and pf138 was obtained. the bioassay results showed that the fungicidal activity of three fusants increased by 43.48%,60.87% and 65.22%。and the production of qinlingmycin increased by 36.59%,74.39% and 91.46%. and three fusants was Successively cultured ten times in the Medium, heredity character was stable.
    SOIL & FERTILIZER·WATER-SAVING IRRIGATION
    Comparing the biological Methods of Assessing Soil N-Supplying Capacity in Calcareous Soil
    Scientia Agricultura Sinica. 2007, 40(7):  1422-1431 . 
    Abstract ( 1353 )   PDF (346KB) ( 875 )   Save
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    Based on pot experiments which including leaching soil initial nitrate and without leaching, we studied the correlations between the 9 biological methods which reflecting soil nitrogen supplying capacity and nitrogen uptake by wheat and maize. Test soils were taken from 25 different calcareous surface soil on Loess Plateau. Dry-wet alternation aerobic incubation method was a modification of the aerobic incubation (for 2 weeks) method according to the actual farmland moisture. The results showed that the nitrogen mineralization potential (N0) was significantly correlated with crop uptake nitrogen with leaching soil initial nitrate (r=0.790, p<0.01). The mineralized nitrogen obtained by aerobic incubation for 4weeks, dry-wet alternation aerobic incubation method and long-term alternate leaching aerobic incubation method had remarkably positive correlations with crop uptake nitrogen with leaching soil initial nitrate (Correlation coefficient were 0.777, 0.768 and 0.764, respectively, p<0.01). The correlation coefficient was low between the water logged incubation method and crop uptake nitrogen with leaching soil initial nitrate (r=0.530, p<0.01). If mineralized nitrogen obtained by any methods included the soil initial nitrate, the correlation between the obtained nitrogen and crop uptake nitrogen without leaching soil initial nitrate was significantly increased. The correlation coefficient were highest for short-term leaching aerobic incubation method and the aerobic incubation (for 2 weeks) method with crop uptake nitrogen (r=0.963,p<0.01). The nitrogen obtained by aerobic incubation for 4weeks, dry-wet alternation aerobic incubation (for 2 weeks) method, long-term alternate leaching aerobic incubation method and N0 had remarkably positive correlations with crop uptake nitrogen without leaching soil initial nitrate (Correlation coefficient were 0.962, 0.959, 0.825 and 0.812, respectively, p<0.01). It could be seen that high contents of soil initial mineral nitrogen, especially nitrate affected the correlations between the biological methods and crop uptake nitrogen. The correlation coefficient between the microbial biomass carbon (BC), microbial biomass nitrogen (BN) with crop uptake nitrogen with leaching initial nitrate were respectively 0.555 (p<0.01) and 0.465 (p<0.05). The correlation between BC, BN with crop uptake nitrogen without leaching initial nitrate were not significantly. Thus, due to long-term alternate leaching aerobic incubation method and N0 needed long term incubating, they were not suitable for general analysis in laboratory. So, we choose the dry-wet alternation aerobic incubation method as the best index for reflecting calcareous soil nitrogen supplying capacity, which were accord with the actual farmland character.
    Abundance and diversity of crop soil insect community at different fertilizer in Xinjiang
    Scientia Agricultura Sinica. 2007, 40(7):  1432-1438 . 
    Abstract ( 1190 )   PDF (335KB) ( 932 )   Save
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    Grey desert soil was a representative of aridity and hungriness belt soil. 80% area of was distributed at Xinjiang. National grey desert soil fertility and fertilizer efficiency long-term monitor site,which built at 1990 was one of 9 National soil fertility and fertilizer efficiency long-term monitor site, its area was 468m2. There were 10 types of fertility treatment, namely abandonment (aband.), no-fertilizer(CK), nitrogen fertilizer(N), nitrogen and phosphor fertilizer(NP), nitrogen and potassium fertilizer(NK),phosphor and potassium fertilizer(PK),nitrogen and phosphor and potassium fertilizer(NPK), NPK with organic matter(fertilizer N : organic N =3:7)(MNPK),150% NPK with organic matter(1.5 MNPK), NPK with straw(SNPK). The effect of different fertilizer treatments on soil insect community at the grey desert soil district in Xinjiang was investigated in Sept. 2004, 90 soil samples and 100 pitfall had been collected and 4915 soil insects(128 unknown) individuals, belonging to 9 Orders and 33 families were obtained by pitfall traps and modified Tullgren methods. The result showed that the number of individual and group, the macro fauna both reached their peaks in abandonment, while mesofauna and micro fauna in nitrogen fertilizer(N) and phosphor and potassium fertilizer(PK)respectively . Of the 10 treatments, most dominant of soil insect composition was in MNPK, most evenness of was nitrogen fertilizer(N).The result by Kruskal- Wallis test indicated that the distribution of the crop soil insect was significantly impacted by different fertilizer treatments (X0.05(9)= 23.38,p < 0.005),soil insect group of the abandoned was significantly different from that of others fertilizer treatments. The soil insect community were divided into five group by Non-matric Multi-Dimensional Scaling(NM-MDS)analysis: (1)NPK,MNPK,1.5MNPK and CK ,(2)NP and PK,(3)NK and N,(4)SNPK and(5)aband., indicated that distribution of soil insect was related to fertilizer character. In the principal component analysis ,two factors explained 87.455% of the total variation among 10 treatments, the factor one explained nitrogen fertilizer(N)and NPK with straw (SNPK)positively effected, while second factor explained the aband. positively affected on soil insect community, that showed the diversified fertilizer did not evenly effect on the soil insect community.
    Impacts of Soil Fertility to Fertilize’s Yields Increasing Benefits and Potentiality in Yuxi area of Henan Province
    Scientia Agricultura Sinica. 2007, 40(7):  1439-1446 . 
    Abstract ( 1010 )   PDF (322KB) ( 841 )   Save
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    【Objective】The objective of this paper was to elucidate the relation of soil fertility and yield increasing benefits and potentiality, in order to rational allocation of fertilizer, and enhance crop yields in Yuxi area of Henan province. 【Method】 Based on field experiments and typical countries’ material, the relation of fertility application amount to crop yields in three type fields in Yuxi area of Henan was studied. 【Result】The results show that it achieved highest yields in flat land, and the yield of slopping land was lowest. Fertilizer could increase effectively yields. But the yield increasing benefits were depressed while land fertility increasing. The some results were got in typical county studied. According to field experiments results, the model of fertilizer application amounts and crop yields was build. And the yields increasing potentiality of Yuxi area had been discussed. If fertilizer of white was 200 kg•hm-2 and corn’s was 150 kg•hm-2,the fertilizer consumption of Yuxi area could been decreasing 31.7%, and the crop yields could been increasing 85.1%.【Conclusion】Land fertility hold remarkable impacts on fertilizer yield increasing benefits, and the yield increasing benefits was decreasing with the increasing of soil fertility. In county area crop yield could be enhanced with fertilizer rational allocation.
    Study on Nutrient Controlled/Slow Release Characteristics and Mechanisms of Super Absorbent Polymer Coated Urea
    Scientia Agricultura Sinica. 2007, 40(7):  1447-1455 . 
    Abstract ( 1488 )   PDF (1092KB) ( 1901 )   Save
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    【Objective】The nutrient controlled/slow release characteristics and mechanisms of super absorbent polymer(SAP) coated urea(SAPCU) was studied. 【Method】 Series products of SAPCUs with single membrane of SAP or with duplex membranes of modified mineral inside and SAP outside were developed by using different types and different water absorbent rates of SAPs as coating material, and big granule urea and modified mineral coated urea(ZECU and PRCU) as the core fertilizers. The structure of the fertilizers were studied by using Scaning Electronic Microscopy(SEM), and the nutrient release characteristics were studied by using water dissolution rate method and soil column leaching method.【Result】The 24 hours N water dissolution rates of SAPCUs were 18.22%~83.87%, and N accumulated leaching rates in four weeks were 40.91%~65.38%, which had 5.21%~40.68% decrease compared with that of urea under same experiment conditions. The capabilities in nutrient controlled/slow release depended on type, water absorbent rate and coating rate of SAP. Urea coated with copolymer of polyacrylamide and polyacrylate had greater capabilities than those with polyacrylate. Both of water and soil dissolution rates of SAPCUs decreased obviously along with the increase of SAP coating rate. However, SAPCUs with duplex membranes had much better effects on nutrient controlled/slow release than those with single membrane, and the effects were also related to the material of inner membrane. Stereoscan photographs showed that both the inner and outer coating membranes of SAPCUs were formed by random closely stacking different size and shape micro particles of coating materials. Furthermore, adhesive cemented the particles and filled up the gaps among them, but there were still micro holes, which served as the channels for urea dissolving out, in and between the stacking layers.【Conclusion】According to the membrane structure characters and nutrient release mechanism, the author thought that SAPCUs had the characteristics of store type of physical controlled-release system, gel controlled-release system and chemical controlled-release system, and had good capabilities in nutrient controlled/slow release. Therefore, SAPCUs are new controlled/slow release fertilizers with good prospect of development and application.
    Research Advance and Development Trends of Biology Water Saving
    Scientia Agricultura Sinica. 2007, 40(7):  1456-1462 . 
    Abstract ( 1431 )   PDF (287KB) ( 1119 )   Save
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    Biology water saving is one of the major fields of water saving agriculture in the future, which has an enormous potential of water saving. In this paper, the necessity and urgency of developing biology water saving were discussed firstly, and then research progresses on biology water saving at home and abroad were introduced as follow aspects: mechanisms of drought resistance and high water use efficiency, criterions for identifing and evaluating drought resistance and water use efficiency, genetic improvement for drought resistance and water use efficiency, water saving irrigation technology based on the physiological regulation and control in crop plants. Major problems in the research field at present were put forward and development trends of biology water saving in the future were discussed at last.
    HORTICULTURE
    Response of Photosynthesis of Micropropagated Apple Plants to Half root and Whole root Water Stress
    Scientia Agricultura Sinica. 2007, 40(7):  1463-1468 . 
    Abstract ( 1154 )   PDF (441KB) ( 1000 )   Save
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    【Objective】 The response of photosynthesis of apple plants to drought stress which simulated drought stress conditions for roots under localized irrigation and alternate partial rootzone drying. Moreover, stomatal and non-stomatal limitations in photosynthesis under water stress were investigated. 【Method】Water stress was simulated using PEG6000. Compared with good water condition, micropropagated ‘Royal Gala’ apple plants were subjected to half root stress (HRS, to simulate localized irrigation), alternate half root stress (AHRS, to simulate alternate partial rootzone drying), whole root stress (WRS). Their net photosynthesis rate (Pn) and the related photosynthetic parameters, photosynthetic pigment, chlorophyll fluorescence, SOD activity, and malondiadehyde (MDA) content were studied. 【Result and conclusion】Pn, stomatal conductance, substomatal CO2 decreased significantly and leaf temperature increased significantly for all plants under water stress, when compared with CK plants. There were no significant differences of photosynthetic pigment and MDA content, SOD activity and chlorophyll fluorescence response between CK and HRS, indicating that decreased Pn of HRS plants was due to mainly stomatal limitation. Similar foliar photosynthetic pigment and MDA content, SOD activity were found between AHRS and CK while AHRS resulted in higher foliar MDA content and lower Fv/F0 and Fv/Fm than CK from 2nd day after the plants were under water stress. It is suggested that the decreased Pn of AHRS plant should be due both stomatal and non-stomatal limitations. Significantly lower foliar photosynthetic pigment content, SOD activity, Fv/F0 and Fv/Fm, but higher foliar MDA content, were observed on WRS 4 or 5 day after the plants were under drought stress than CK, indicating that the decreased Pn in the first few days after water stress was applied should be due to mainly stomatal limitation, and non stomatal limitation should play an important role thereafter in regulating Pn for WRS plants.
    Effects of regulation of zinc and iron accumulation and translocation in Malus Hupehensis Rehd under zinc and iron interaction
    Yan-An Wang Dian-peng Dong Kun Li De-quan Li Huai-rui Shu
    Scientia Agricultura Sinica. 2007, 40(7):  1469-1478 . 
    Abstract ( 1295 )   PDF (303KB) ( 1005 )   Save
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    【OBJECTIVE】Zinc and iron interaction is one of the reasons that cause to the apples physiological disturbance symptoms. Malus Hupehensis Rehd is the most common use rootstock of apple. 【METHOD】We studied the effects of regulation of zinc and iron absorb, translocation, distribute and accumulation in Malus Hupehensis R. under zinc and iron interaction, with solution culture and orthogonal design. 【RESULTS】The results shows that there were significantly effect on the zinc and iron concentration in roots and stems, but it is not significant on leaves under zinc and iron interaction. That’s to say, the interaction of zinc and iron effected accumulation and translocation of zinc and iron on Malus Hupehensis R.’s roots. 【CONCLUSION】The iron and zinc absorb and translocation in roots was promoted under lower iron stress. Under the high iron stress, the zinc and iron hyperaccumulation was promoted, but the zinc translocation to the stem and leaves was inhibited.
    Long-term in vitro culture of the callus of Petunia hybrida and ISSR analysis of the regenerated plants
    Scientia Agricultura Sinica. 2007, 40(7):  1479-1485 . 
    Abstract ( 1196 )   PDF (404KB) ( 957 )   Save
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    【Objective】A Long-term in vitro culture plant regeneration system of Petunia hybrida is useful not only in obtaining somatic variants and thereafter to select superior lines, but also in analyzing the stability of foreign gene in the cells during long-term culture and plant regeneration. 【Method】Different callus were obtained by culturing the leave explants of one double flower Petunia plant on the media supplemented with different combinations of auxin and cytokinnins. Calli were sub-cultured on the media of MS+ BA 2.0 mg•L-1+0.5 mg•L-1 NAA+200 mg•L-1 CH and MS+ BA 0.5 mg•L-1+0.5 mg•L-1 NAA+200 mg•L-1 CH for more than 3 years under different light condition. The total DNA of 20 regenerated plants were analyzed by ISSR utilizing 8 primers. 【Result】 Plants were successfully regenerated from Long-term cultured callus when transferred onto shoot induction media supplemented with low concentration of PGR. After continuous culture on the media for at least three times, all adventitious shoots developed into complete plants of normal morphological characteristics. ISSR analysis showed that there was dramatic genetic variation among somatic variants. 【Conclusion】Plant regeneration could be successfully implemented after long-term subculture of the callus of Petunia hybrida in higher concentration BA media when they were transferred onto shoot induction media supplemented with low concentration of PGR. The culture system presented here is effective in obtaining somatic variants for Petunia hybrida.
    Identification of 16SrDNA and Research on Acylated Homoserine Lactones Produced by Pseudomomas Isolated from the Fish
    Scientia Agricultura Sinica. 2007, 40(7):  1486-1491 . 
    Abstract ( 1320 )   PDF (363KB) ( 1026 )   Save
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    Three Gram-negative bacteria were isolated from the commercial fresh fish and considered to be the pseudomonas group , an important microorganism that caused the fish spoilage ,by analysis of 16SrDNA sequence.The characteristics (Protase ,siderophore(s) ,formation biofilm) involved food spoilage were assayed . N-acyl-homoserine lactones (AHLs) were the important quorum sensing molecules and regulated the expression of many characteristics in Gram-negative .Three isolates produced the AHLs incolved in quorum sensing.Thin-layer chromatography revealed presence of two AHLs in extract from the Pseudomonas fluorescens FLM05-1and Pseudomonas fluorescens FLM05-2 and the main signal molecule was N-3-oxo-octanoyl-homoserine lactone.Production siderophore , protase of FLM05-2 were significantly reduced by co-incubation with AHL degrader Pseudomonas fluorescens P3(pME6863). It was suggested that QS play an important role in the food spoilage. This was first study of production AHLs ,quorum sensing signal molecule by the pseudomonas , and new strategies were provided for food preservation based on quorum sensing
    Changs of the Main Carotenoids Pigment Contents during the Drying Processes of the Differents Harvest Stage Fruits of Lycium barbarum L.
    Scientia Agricultura Sinica. 2007, 40(7):  1492-1497 . 
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    Abstract:As one of functional components, Carotenoids as zeaxanthin, beta-carotene and esterified zeaxanthin are the main constitute in Lycium barbarum L.. During Lycium barbarum L fresh fruit dried processing, owing to the harsh processing conditions, carotenoids content had a complicated biosynthesis and degradation reaction which effected fruit herbal function and fruit appearance. Experimentation with HPLC indicate that carotenoid contents had been changing in different harvest stage of fruit dried processing. At the beginning of drying period, zeaxanthin and beta-carotene contents in fruits had increased dramatically, 2-22 times of that in fresh fruits. In middle of drying period, degradation occurred to some extent and autumn fruit degraded to a large extent. At the end of drying period, zeaxanthin and beta-carotene contents increased in a small extent until to balance. Zeaxanthin dipalmitate had a whole degradation at the beginning of fruit drying, reached to 40 per cent or higher, while zeaxanthin dipalmitate content had increased a little then reached to balance. The total carotenoid content analysis showed that summer fruit had higher carotenoid content than that of autumn fruit.The different changes of carotenoids during the drying processes provide the reference for improve on drying technics.
    ANIMAL SCIENCE·VETERINARY SCIENCERE·SOURCE INSECT
    PstI-RFLPs and BanI-RFLPs in AGPAT6 Intron2 and their Effects on Milk Performance of Dairy Cattle
    Scientia Agricultura Sinica. 2007, 40(7):  1498-1503 . 
    Abstract ( 1145 )   PDF (358KB) ( 1145 )   Save
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    【Objective】The objective of this study was to study the polymorphism of AGPAT6 gene and relationship between the polymorphisms and the milk performance of dairy cattle.【Method】 PCR-RFLPs method was used for identification polymorphism in cloned the 2nd intron of AGPAT6 (1-acyl-sn-glycerol-3-phosphate acyltransferase zeta). Genotypic effects of the 2nd intron of AGPAT6 on milk yield, milk fat percentage, milk protein percentage, milk dry material and somatic cell score(SCS) were analyzed. 【Result】A PstI-RFLPs and a BanI-RFLPs were detected in the 2nd intron of AGPAT6. The PstI-RFLPs and BanI-RFLPs were common in all the detected breeds(lines). The PstI-RFLPs and BanI-RFLPs were significant relation with average milk fat percentage of Holstein(P < 0.05). Individuals with genotype BB had higher milk fat percentage. The PstI-RFLPs was significant relation with SCS of Holstein(P < 0.05), and individuals bearing AA genotype had higher ( P < 0.05) SCS. The BanI -RFLPs was significant relation with 305-days matured equivalency of Holstein(P < 0.05), and individuals with genotype AA had higher ( P < 0.05) milk yield. The PstI-RFLPs was significant relation with average milk fat percentage and average dry material of Long-Zhou Cow(P < 0.05), but no significant associations were founded between BanI –RFLPs and milk production traits in Long -Zhou Cow. 【Conclusion】The B allele of PstI-RFLPs was favorable allele of milk fat percentage, SCS for Holstein and milk dry material for Long -Zhou Cow. The B allele of BanI -RFLPs was favorable allele of milk fat percentage and the A allele of BanI -RFLPs was favorable allele of 305-days matured equivalency for Holstein.
    Effect of dietary manganese source on carcass traits and meat quality of broilers and modes of action
    Scientia Agricultura Sinica. 2007, 40(7):  1504-1514 . 
    Abstract ( 1169 )   PDF (271KB) ( 909 )   Save
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    An experiment was conducted using a total of 336 day-old AA male broilers to investigate the effect of dietary manganese (Mn) source on carcass traits, meat quality, relative enzyme activities in abdominal fat and meat, and MnSOD mRNA level in meat. The broilers were randomly allotted to one of seven treatments in a completely randomized design involving a 3×3 factorial arrangement of treatments and fed the corn-soybean meal basal diets and the basal diet supplemented with 100 or 200 mg Mn/kg as Mn sulfate (MnSO4•H2O), Mn amino acid A (Mn AA A) or Mn amino acid B (Mn AA B) with moderate chelation strength, respectively, for a duration of 42 days. Birds fed diets supplemented with Mn had lower (P﹤0.10) percentages of abdominal fat, lipoprotein lipase (LPL) and malate dehydrogenase (MDH) activities in abdominal fat, and malondialdehyde (MDA) content in leg muscle than those fed the control diet. Birds fed diet supplemented with Mn from Mn AA A or Mn AA B had lower (P﹤0.05) LPL activities in abdominal fat than those fed diet supplemented with Mn sulfate. Birds fed diets supplemented with Mn had higher (P﹤0.02) hormone sensitive lipase (HSL) activities in abdominal fat, and Mn-containing superoxide dismutase (MnSOD) activities and mRNA level in breast and leg muscle mitochondria. Birds fed diets supplemented with Mn from Mn-AA A had higher (P﹤0.02) MnSOD mRNA level in leg muscle mitochondria than those fed diets supplemented with Mn from Mn sulfate. The results indicate that organic Mn with the moderate complex strength (Mn AA A) was more available than inorganic Mn source to decrease LPL activity in abdominal fat and increase MnSOD gene expression in mitochondria of leg muscle cells in broilers, leading to the improvement of carcass traits and meat quality.
    Effect of Adipocyte Plasma Membrane Antibody on Carcass Composition and Lipid Metabolism-related Hormones and Enzymes in the Pig
    Scientia Agricultura Sinica. 2007, 40(7):  1515-1522 . 
    Abstract ( 1110 )   PDF (400KB) ( 888 )   Save
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    One hundred and sixty crossbred (Duroc-Jersey×Landrace·Meishan) pigs weighing approximately 27 kg were allocated randomly into treatment and control groups. The treatment group was fed with the basal diet supplemented with 75mg/kg oral type antibody against adipocyte plasma membrane (OAAb). Following a 104-day trial, the pigs were slaughtered, the carcass composition was measured and the weights of internal fat depots were recorded, Blood and tissue samples were taken for further analysis. Serum concentrations of insulin and leptin were determined with RIA. Diameters of adipocytes from different fat depots were measured by using histological methods, DNA/RNA concentrations and NADP-MDH, lipoprotein lipase (LPL) activity were analyzed. Dietary supplementation of OAAb increased lean mass by 10.3% (P < 0.01) with unaffected dressing percentage. Backfat thickness at 6th~7th rib was reduced by 24.14% (P<0.01), the perirenal,mesenteric and subcutaneous fat depots were reduced by 27.27%(P<0.05),20.42%(P<0.01) and 29.21%(P<0.01),respectively, However, the intramuscular fat content of the longissimus muscle remained unaffected. Serum concentrations of insulin and leptin were reduced by 26.19%(P<0.05) and 26.53%(P<0.05), respectively. Dietary supplementation of OAAb reduced adipocyte size in all the three different adipose pads (P<0.05), LPL activity in adipose tissue and the ratio of LPL activity between adipose tissue and skeletal muscle were reduced significantly (P<0.05) whereas NADP-MDH activity was unaffected. We first demonstrated the oral effect of OAAb on carcass composition in the pig and the changes of serum insulin and leptin levels as well as the tissue LPL activity may be involved in the acting mechanism.
    Expression and bioactivity of goat IL-18 mature protein
    Scientia Agricultura Sinica. 2007, 40(7):  1523-1527 . 
    Abstract ( 1059 )   PDF (308KB) ( 771 )   Save
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    The gIL-18 gene was cloned into pET32a(+) vector. The recombinant plasmid pET-gIL-18 in E.Coli BL21(DE3) was introduced by 1mmol/L IPTG for 4h or more time for expression. The fusion protein of pET and gIL-18 was expressed. SDS-PAGE analysis suggests that the recombinant protein is about 38ku. Western-blotting indicated recombinant gIL-18 showed well reaction to its specific multi-antibodies. The recombinant protein can stimulate the proliferation of PBMCs and induce IFN-γproduction in MDBK cells after denature、renature and purified. The recombinat protein also can protect mice against the attack of PRV virulent strains. Which are helpful for the clinical use of this cytokines.
    The First Record of Cryptosporidium from Ostrich in China and
    Longxian Zhang
    Scientia Agricultura Sinica. 2007, 40(7):  1528-1534 . 
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    A survey of Cryptosporidium was performed in 404 samples from ostriches in ZhengZhou, with the Sheather's sugar flotation technique.The cryptosporidia infection percentage in ostriches was 2.48%(10/404), the oocyst is of 5.43μm×4.38μm with shape index of 1.24(n=50). The pathogenicity of the Cryptosporidium strain to ostriches,chickens and mice were studied. Main clinical signs of cough, asthma, sneezing, cachexia, dyspnea could be observed in the chickens and ostriches that infected with the oocysts ,and the signs in ostriches was mild,but there was no symptom as that of described as above in mice and no oocysts were found in their feces. The regulation of shedding oocysts in chicken was different with it in ostrich ,there were multiple peaks in ostrich.The experiments were carried out on pathology of some organs in young ostriches that infected with Cryptosporidium from ostriches. We found that Cryptosporidium derived from ostrich mainly parasitized in cloaca and bursa of Fabricious of ostriches, mainly caused mucous membrane tumefaction and epithelium cell swell,.The oocyst is identified as Cryptosporidium baileyi according to its’ morphological characteristics, the result of pathogenicity to ostriches, chickens and mice.
    Studies on mtDNA Polymorphisms of Apis cerana Distributed in Different Geographic Areas within China
    Scientia Agricultura Sinica. 2007, 40(7):  1535-1542 . 
    Abstract ( 1420 )   PDF (549KB) ( 1099 )   Save
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    RESEARCH NOTES
    Cytology Research on the Anther Abortion of Three Male Sterility Lines in Rapeseed(Brassica napus L.)
    Scientia Agricultura Sinica. 2007, 40(7):  1543-1549 . 
    Abstract ( 1313 )   PDF (501KB) ( 1111 )   Save
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    With cytoplasmic male sterility line 392A, recessive double-family genic male sterility line 86A and dominant double-family genic male sterility line 629A in rapeseed(Brassica Napus L) as materials, we do cell anatomy research on the anther abortion processes of male sterility lines in rapeseed(Brassica Napus L) and make a comparison with 392B. The result indicates that 86A and 629A both belong to pollen female cell abortion and whether 392A will have an abortion is decided by temperature. When it is≥10℃ on the average during the day, there will be no pollen sacs and sterility arises. When the temperature is lower, fertility happens. We also find that 392A is influenced by temperature before the period of archesporical cells.
    Biological and Anatomic Studies of Abortive Pollen in Male Sterile Monogerm Sugar Beet
    Scientia Agricultura Sinica. 2007, 40(7):  1550-1558 . 
    Abstract ( 1067 )   PDF (1789KB) ( 899 )   Save
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    The differences of biological and anatomic characteristic of abortive pollen in sugar beet between male sterile line and maintenance line were examined in the laboratory of Sugar Beet Research Institute. The development phase and process of bud and pollen stained with paraffin slicer and Ai-shi haematine crystal, safranine and fast green in the three group monogerm sugar beets with male sterile line and maintenance line were observed under the light microscope. The results showed that there were significant differences between the two lines in the flower structure. The pale green concave anther could be seen clearly before flowering; and the anther without curl changed into white or pale green in the maintenance line after flowering. But for male sterile line, anther and the pollen abnormally developed, and the abortive courses can be divided into four phases, which were mainly that tapetum and middle-layer separated during tetrad period, development of microspore stopped at the stage of its forming and tapetum and microspore gradually disappeared after conglutination, those resulted in the anther drying and shriveling, the pollen was abortive in the end.
    Difference of distribution and virulence of Ralstonia solanacearum Smith in the plant
    Scientia Agricultura Sinica. 2007, 40(7):  1559-1566 . 
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    The difference of distribution and virulence of Ralstonia solanacearum Smith in the plant was investigated to preliminary discuss the relationship between the pathogen and the plant from the point of view of niche. The results showed that the average contents of R. solanacearum in the infected plants of tomato and eggplant (> 100×108 cfu/g) were significantly higher than in those of tobacco, peanut and ginger (< 70×108 cfu/g). The distribution of R. solanacearum was root> stem above middle part > stem below middle part in tomato, reduced gradually from root to top stem in eggplant and peanut, was significantly higher in root and middle stem than low and top stems in tobacco, and was higher in low stem than tuber and stem above middle. The average of attenuation indexes in the infected plants of different host plants were descending in turn as eggplant > tobacco > peanut > ginger; according to the standard of attenuation index, the pathogen from ginger exhibited as virulent strain with attenuation index of 0.49 (< 0.60), while that from eggplant was close to avirulent strain with attenuation index of 0.80 and those form tobacco, peanut and tomato belonged to strain of uncertain virulence with attenuation index of 0.64-0.70. When both healthy and infected plants of eggplant, ginger and peanut were tested, only peanut had R. solanacearum in the two kinds of plants with different infection status. At three disease stages, all the amounts of R. solanacearum in low stem of eggplant were higher than in middle and top stems; the content at different parts all reduced while the course of disease developed from initial stage to middle stage, but no significant difference was found between middle and later stages. The pathogeny didn’t display obviously virulent in the plants of eggplant at different disease stage, but the attenuation index reduced as the disease developed which suggested that the virulence increased.
    Study of different temperature Storage an Chilling Injury in soft Peach of south
    Scientia Agricultura Sinica. 2007, 40(7):  1567-1572 . 
    Abstract ( 1096 )   PDF (408KB) ( 1177 )   Save
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    【OBJECTIVE】Study of the storage effect and relationship between physiological variations and chilling injury in soft Peach of south at different temperature, and research the suitable storage condition of soft Peach of south.【METHOD】Different temperature (25℃、0℃、2℃、5℃) were used to store the soft Peach of south, observed and measured the biochemical and physiological changes such as respiratory, conductivity, hardness, the content of MDA, TSS, total acid, sugar and Vc, et al. 【RESULTS】The results indicated that at 0℃ peach can normally post-ripe , and had normal flavor when stored for 28d. But for the condition of 2℃ and 5℃, the different degree of chilling injury all happened when stored for 7d. Additionally, when took out the peach that stored for 28d at 0℃ and then stored at 25℃, it could normally soft in the shelf-life of 3d.【CONCLUSION】For the soft Peach of south , the optimal storage condition was stored for 28d at 0℃; The shelf-life was 3d when took out the peach that stored for 28d at 0℃ and then stored at 25℃; The peach could happened the different degree of chilling injury stored at 2℃ and 5℃.
    The Measurement of Elasticity Coefficient--Young’s Modulus of the Zona Pellucida of Porcine Oocytes
    Scientia Agricultura Sinica. 2007, 40(7):  1573-1578 . 
    Abstract ( 1423 )   PDF (474KB) ( 1086 )   Save
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    The mechanics property of the zona pellucida of porcine oocytes was investigated in this study. Under 39℃ conditions, the Young’s modulus of the zona pellucida, of porcine oocytes (n=76, 7 replicates in total) cultured in vitro for 44-48 hours and of which nuclear matured and not matured, were measured. The elasticity modulus of the zona pellucida of these oocytes is (1.43±0.29)×104 Pa. Also an computer software for measuring the Young’s modulus of the zona pellucida of oocytes was made.