Scientia Agricultura Sinica

Effects of Genetic Background on Expression of QTL for Nitrogen Efficiency in Irrigated Rice and Upland Rice#br#

LI Ya-fei,LI Mao-mao,CAO Gui-lan,HAN Long-zhi

Scientia Agricultura Sinica. 2010, 43(21): 4331-4340 . doi:10.3864/j.issn.0578-1752.2010.21.001

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【Objective】 Elite alleles of nitrogen efficiency derived from different irrigated rice and upland rice were detected, and the effects of genetic background on expression of quantitative trait locus (QTL) were analyzed for providing a theoretical basis for fine mapping and molecular marker-assisted breeding of nitrogen efficiency in rice. 【Method】 QTL of some traits associated with nitrogen utilization efficiency were identified using two japonica × japonica recombinant inbred lines (RILs). The first RILs was from the cross IAPAR-9 (upland rice)/Liaoyan241 (irrigated rice), and the second RILs was from the cross IAPAR-9/Akihikari (irrigated rice). 【Result】 A total of 31 QTLs referring some traits correlated with nitrogen utilization efficiency in the first RILs were detected on all chromosomes except chromosomes 6, 7 and 10. QTLs controlling different traits were mapped on the same or adjacent intervals, forming 9 clusters in rice chromosomes. In the second RILs, 33 QTLs for some traits associated with nitrogen utilization efficiency were found on all chromosomes except chromosomes 4 and 10, forming 7 clusters in rice chromosomes. 【Conclusion】 Genetic background had a significant impact on QTL expression of some traits associated with nitrogen utilization efficiency. The interval, RM3421-RM5404, in chromosome 2 and the adjacent interval with RM8264 in chromosome 8, where QTLs underlying traits associated with nitrogen utilization efficiency stably expressed across different genetic backgrounds, may be beneficial to MAS for nitrogen efficiency in rice.

Molecular Cloning and Expression Analysis of Two Splice Forms of the Protein Phosphorylation Homologous Gene (GhSOS2) During the Salt Stress Pathway in Cotton#br#

LI Fu-zhen,QIU Xin-mian,WANG Mei-xing,LIU Chuan-liang

Scientia Agricultura Sinica. 2010, 43(21): 4341-4348 . doi:10.3864/j.issn.0578-1752.2010.21.002

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【Objective】 The objective of this study is to understand the salt stress related genes expression and clone the key salt-tolerance genes under the conditions of salt tolerance in cotton. 【Method】 Through screening of the cotton EST databases and integration of the objective EST sequences, a homologous gene named GhSOS2 of plasma membrane Na+/H+ reverse transporter protein phosphorylation was obtained by RT-PCR method, respectively, under the conditions of non-salt and salt stress treatment of Zhongmiansuo 49. Meanwhile, the expression characteristics were analyzed by real time quantitative PCR method. 【Result】 The sequence analysis showed that there were two splice forms of GhSOS2a (GenBank accession number: GU188960) and GhSOS2b (GenBank accession number: GU188961), encoding 445 and 421 amino acid residues, respectively. Compared to GhSOS2b, an extra exon of 72 bp exists in GhSOS2a due to different splicing ways. Real time quantitative PCR analysis showed that GhSOS2a was expressed in the mixture tissue of root and stem, leaf tissue under both non-salt and salt stress conditions. However, GhSOS2b was expressed in the mixture tissue of root and stem, leaf tissue only under the conditions of salt stress. Furthermore, its expression was much higher than that of the GhSOS2a. 【Conclusion】 GhSOS2 gene was alternatively spliced into two kinds of splice forms under the condition of salt stress in cotton. The splice form GhSOS2b may be mainly involved and play an important role in the pathway of cotton plasma membrane Na+/H+ reverse transporter.

Identification of AFLP Markers Linked to a Novel Rust Resistance Gene in Foxtail Millet#br#

ZHAO Li-qiang,PAN Wen-jia,MA Ji-fang,WENG Qiao-yun,DONG Li,QUAN Jian-zhang,XING Ji-hong,DONG Zhi-ping,DONG Jin-gao

Scientia Agricultura Sinica. 2010, 43(21): 4349-4355 . doi:10.3864/j.issn.0578-1752.2010.21.003

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【Objective】 The AFLP makers linked to rust resistance gene in foxtail millet were studied as they are useful for new resistance genes and the rational usage of marker-assisted selection in millet resistance breeding. 【Method】 A cross between resistant cultivar ‘Shilixiang’ and susceptible cultivar ‘Yugu 1’ was used to map foxtail millet rust resistance gene(s). Based on the identification result of F1 and F2 progenies inoculated with the Uromyces setariae-italicae Yoshino strains 93-5, the resistant and susceptible pools were established. With 128 EcoRⅠ/MseⅠ primer combinations, AFLP analysis was performed on parents and two bulks. AFLP makers were applied to construct a genetic linkage map of resistance gene in an F2 population of 131 individuals, which were sequenced and then converted to stable SCAR markers. 【Result】 The inoculation test showed that the resistance of ‘Shilixiang’ to millet rust was controlled by one dominant gene. In 128 AFLP primer combinations, three markers were found to be linked to the rust resistance gene, with the genetic distance of 7.4, 9., and 27.4 cM, respectively, which was tentatively named Rusi1. A preliminary genetic linkage map was constructed using 3 AFLP markers. Furthermore, the three cloned fragments were sequenced and then E+CTT/M+TAC-256 was successfully converted to a stable SCAR marker. Genetic linkage map of foxtail millet rust resistance gene Rusi1 was constructed. 【Conclusion】 The resistance to millet rust in ‘Shilixiang’ is controlled by a single dominant gene. The gene Rusi, derived from ‘Shilixiang’, is a rust resistance gene found in foxtail millet.

Effect of Soil Compaction Stress on Nutrient Absorption and Distribution and Yield in Maize Under Different Soil Types#br#

WANG Qun,ZHANG Xue-lin,LI Quan-zhong,XUE Shuai,LI Chao-hai

Scientia Agricultura Sinica. 2010, 43(21): 4356-4366 . doi:10.3864/j.issn.0578-1752.2010.21.004

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【Objective】 The objective of this study was to identify the responses of nutrient uptake and distribution and yield in maize to soil compaction under different soil types. 【Method】 A two-year barrel-culture experiment was conducted in 2007-2008 with three soil types and two levels of soil compaction on the farm of Henan Agricultural University. The characteristics of nutrient uptake and distribution, and yield in maize were studied. 【Result】 The results showed that root growth was restricted in the three selected soils under soil compaction stress. The maximum root length and dry weight were found in the fluvo-aquic soil while the minmum were observed in the yellow cinnamon soil. The accumulation of N, P, and K uptaken per plant were significantly different among the three selected soils and were the highest in the fluvo-aquic soil, followed by the lime concretion black soil and yellow cinnamon soil. Under the soil compaction circumstances, more nutrients in leaves were transferred to the grains than those in the stems and sheaths. The highest transferring rates of N, P, and K were found in the yellow cinnamon soil, followed by the lime concretion black soil, and the lowest in the fluvo-aquic soil. With the relief of soil compaction, length and dry weight of roots increased significantly in all selected soils, resulting in the increase in the total nutrient uptake per plant and yield. Among the three selected soils, soil compaction had a weaker effect on corn nutrient uptake and yield in the fluvo-aquic soil than in the lime concretion black soil and yellow cinnamon soil. The transferring rates of N, P, and K from vegetative organs to grains increased with increase of soil compaction. 【Conclusion】 Root growth, nutrient uptake and utilization were substantially affected by soil compaction stress, and yield improvement could be obtained by decreasing soil compaction.

Quantitative Study on the Relationships Between Grain Yield and Ear 3-D Geometry in Maize#br#

YANG Jin-zhong,ZHANG Hong-sheng,ZHAO Yan-ming,SONG Xi-yun,WANG Xin-qin

Scientia Agricultura Sinica. 2010, 43(21): 4367-4374 . doi:10.3864/j.issn.0578-1752.2010.21.005

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【Objective】 Ear geometry conditions the grain yield potential in maize. The objective of this study is to quantify the relationships between grain yield and ear 3-D geometry in maize as a pathway to higher crop yield. 【Method】 Ear geometric features were extracted using image analysis from images of ears for each of 10 cultivars in maize. Both grain yield correlations to ear sizes at different geometric dimensions and its regressions as functions of ear shape and size combinations were studied. Three regression equations were built with 3 combinations as predictors of ear extent (EE) and ear length (EL) and width (ED), EE and ear area (EA), and EE and ear volume (EV). 【Result】 These equations in that order explained 77.7%, 70% and 78.7% of total grain yield variations among 10 cultivars studied, 81.7%, 81.3% and 82.% of that among micro-envionments within fields. Simple determination coefficients between grain yield and ear sizes were not significant for EL, EW, EA or EV when evaluated cross all cultivar averages, while that were 0.387, 0.167, 0.590, 0.571 for EL, EW, EA and EV, respectively, in the background of micro-envionments within fields. 【Conclusion】 EE is a novel important trait featuring ear geomotry in maize, and its combinations with ear geometric size features may predict grain yields at high accuracy. Size features ranks of importance as an indirect indicator of grain yields are EV＞EA＞EL and EW.

Historical Study on the Seed Development of Ancient China#br#

CHENG Guang-lei,XIA Jing-yuan,ZHANG Chun-qing

Scientia Agricultura Sinica. 2010, 43(21): 4375-4383 . doi:10.3864/j.issn.0578-1752.2010.21.006

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【Objective】 To clear the ancient history of seed biology in China and to know the contribution of China to the ancient seed biology for to providing references and a basis for development of modern seed science and for study of the history of seed biology. 【Method】 The relational knowledge of seed development biology from the 22 century BC to the 19th century was summed up to take the contents of modern seed biology as a line through consulting ancient books and references. 【Result】 The ancient knowledge including the overall understanding of seed development, the influence of water and fertilizer and agronomic practices on seed development, and the discovery and prevention of seed abortion, and seed maturity and after-ripening and so on were studied. 【Conclusion】 The result showed that in ancient China, through long-term observation and practice made by working people, a lot of knowledge about seed development was found, especially the influencing factors on seed development. Although the ancient knowledge is accumulated from experience and records of phenomenon of seed growth, but it is basically in accordance with modern seed science, and is very useful for study modern seed developmental biology.

Spatial Distribution Optimization of Wheat Planting Area Based on Regional Area Control#br#

ZHANG Jin-shui,ZHAO Lian,CHEN Lian-qun,HU Tan-gao,DONG Yan-sheng2

Scientia Agricultura Sinica. 2010, 43(21): 4384-4391 . doi:10.3864/j.issn.0578-1752.2010.21.007

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【Objective】 According to disadvantage of traditional method combing remote sensing and sampling method which only obtains the regional area, this paper brought up a new method for optimizing wheat distribution with the whole regional area.【Method】 Incorporating the advantages of soft and hard classification, the wheat extent can be divided into three parts, pure, mixed and non-wheat pixels. Based on the regional winter area, the threshold was set and the winter area was obtained, which improved not only the regional accuracy but also spatial distribution accuracy. 【Result】 The result shows that RMSE of proposed method is 0.13, which is better than hard classification result and soft classification result, which is 0.16 and 0.20, respectively. All above verifies the proposed method is effective. 【Conclusion】 Winter wheat area method with regional area control provides a good basis for the large scale crop planting area survey.

Triplex PCR Detection of Botrytis cinerea, Colletotrichum gloeosporioides and Verticillium dahliae in Infected Strawberry Plant Tissues#br#

WANG Nan,WANG Jian,YIN Dan-han,GAO Guan-peng,WANG Wei

Scientia Agricultura Sinica. 2010, 43(21): 4392-4400 . doi:10.3864/j.issn.0578-1752.2010.21.008

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【Objective】 Reaction components and parameters of triplex PCR system were optimized to establish the method for the detection of Botrytis cinerea, Colletotrichum gloeosporioides and Verticillium dahliae simultaneously at early stage. 【Method】Three sets of specific primers were selected and the annealing temperature of PCR reaction was optimized. The three levels of six factors (three primers, Taq DNA polymerase, dNTP and Mg2+) in multiplex PCR system were evaluated using orthogonal design method. 【Result】 The triplex PCR system for simultaneous detection of these three pathogens in strawberry was successfully established and verified. The volume of reaction system which could amplify three specific bands of 729 bp, 539 bp and 450 bp was 25 μL and the annealing temperature was 50℃. The reaction mix contained 0.32 μmol?L-1 of primer C729+/-, 0.032 μmol?L-1 of primer DB19/DB2, 0.32 μmol?L-1 of primer CgInt/ITS4, 1.5 U Taq DNA polymerase, 0.15 mmol?L-1 dNTP and 1.6 mmol?L-1 MgCl2. 【Conclusion】 The triplex PCR system can detect B. cinerea, C. gloeosporioides and V. dahliae in infected plant tissues and soil with the sensitivity of 10 pg DNA.

Dynamics in Kanamycin-Resistant Bacterial Population and Detection of npt II Gene Flow in the Rhizosphere of Insect-Resistant Transgenic Cotton#br#

WANG Zhen,DENG Xin,ZHAO Ting-chang,LIU Xue-min

Scientia Agricultura Sinica. 2010, 43(21): 4401-4408 . doi:10.3864/j.issn.0578-1752.2010.21.009

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【Objective】 The dynamics in kanamycin-resistant bacterial population were studied and the flow of npt II in the rhizosphere of insect-resistant transgenic cotton was monitored. 【Method】 Insect-resistant transgenic cotton GK1, GK19, 33B, and SGK3, and corresponding receptor cotton 33, Shiyuan 321 and Simian No.3 cotton were sampled at different growing stages. Dynamics and diversity among kanamycin-resistant bacterial populations in the rhizosphere were analyzed with the conventional culture methods. In addition, the flow of npt II was monitored by germ PCR, and the unique primer was designed from the sequence of npt II, the CK was pBI121 plasmids. 【Result】 The population of kanamycin-resistant bacteria in cotton rhizosphere decreased along with the cotton growth. Significant difference was found among the same cotton cultivar at different sample times, but little difference was found between insect-resistant transgenic cotton and corresponding receptor cotton at the same time. Simpson diversity index, Shannon-Wiener diversity index and Pielou’s evenness index were calculated, and the results showed that the diversity index of kanamycin-resistant bacterial population in rhizosphere of conventional cotton was larger than that of insect-resistant transgenic cotton. The monitoring result by PCR amplication showed that positive PCR products of 18 strains were found from 21 kanamycin-resistant strains, no sequences had 100% similarity with the known nptⅡ gene sequence. 【Conclusion】 It was suggested that little differences were found among the total rhizospheric population of kanamycin-resistant bacteria between insect-resistant transgenic cotton lines and their receptor cotton cultivars, the diversity index of rhizospheric kanamycin-resistant bacteria population of receptor cotton cultivar is larger than the corresponding insect-resistant transgenic cotton line, and is more even and stable. No gene flow of nptⅡ in insect-resistant transgenic cottons into the rhizosphere bacteria was detected.

Biological Characteristics, Influence on Growth of Wheat and Its Economical Threshold of Phalaris paradoxa L. and Phalaris minor Retz.#br#

XU Gao-feng,ZHANG Fu-dou,LI Tian-lin,SHAN Qin-li,ZHANG Yun,WU Di

Scientia Agricultura Sinica. 2010, 43(21): 4409-4417 . doi:10.3864/j.issn.0578-1752.2010.21.010

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【Objective】 To understand, prevent and control the invasive species of Phalaris paradoxa L. and Phalaris minor Retz., their biological characteristics, competitive effects, yield characteristics and economical threshold to wheat Yunxuan 2 were studied. 【Method】 With wheat Yunxuan 2 as receptor and control plant, additive series experiments and regression fitting methods were used to study the difference in biological characteristics, analyze the competitive effects, yield characteristics and economical threshold of Phalaris paradoxa L. and Phalaris minor Retz. in greenhouse. 【Result】 Plant height, leaf length, leaf width and growth from sowing to each periods of duration of the tested wheat were greater than Phalaris paradoxa L., Phalaris minor Retz. in the vegetative period, but the growth of Phalaris paradoxa L. and Phalaris minor Retz. was faster than the wheat in reproductive period. The growing period was in the order of Phalaris minor Retz. (129.33 d)＞Yunxuan 2 (128.78 d)＞Phalaris paradoxa L. (124.78 d). The competitive power of Phalaris paradoxa L. and Phalaris minor Retz. was positively correlated with density which gradually increased to tested wheat with the increasing plant density, but the competitive power of Phalaris minor Retz. was stronger than Phalaris paradoxa L. Yield characteristics of tested wheat were affected because of the competitive effects. The regression method of y=96.5687×(1-e-[(x+2.1672)/54.5604]^0.8220) and y=96.3346×(1-e-[(x+2.5306)/46.7132]^0.7918) were the best for describing the relationship between Phalaris paradoxa L., Phalaris minor Retz. and yield lose of wheat. In wheat field, the economical thresholds of Phalaris paradoxa L. and Phalaris minor Retz. were 3.07 and 2.63 plant/m2 for manual weeding and 1.71 and 1.61 plant/m2 for fenoxaprop-ethyl chemical control. 【Conclusion】 Difference in biological characteristics of Phalaris paradoxa L., Phalaris minor Retz. and tested wheat is existed under the same planting condition in greenhouse. The competitive power of Phalaris paradoxa L. and Phalaris minor Retz. is strong to tested wheat which can affect yield of wheat significantly.

Ecological Effects of Different Fertilizations on Red Earth Paddy Soil with K-deficiency #br#

CHEN Jian-guo,ZHANG Yang-zhu,ZENG Xi-bai,TAN Zhou-jin,ZHOU Qing,ZHOU Wei-jun

Scientia Agricultura Sinica. 2010, 43(21): 4418-4426 . doi:10.3864/j.issn.0578-1752.2010.21.011

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【Objective】 To study the ecological effects of different fertilizations on paddy soil with K-deficiency, a pot-experiment by cropping rice had been conducted for 3.5 years. 【Method】 The experiment was carried out with cropping rice in pot and treated with balanced application of N, P and K fertilizer adding befitting quantity of Si, K and organic manure which close related to rice growth. 【Result】 The rice growing healthily by balanced application of N, P and K fertilizer enhanced internal nutrient use efficiency and the rice yield, which increased up to an extent from 27.7% (NPK treatment) to 51.5% (NPKSi treatment), and produced large amounts of secretion and oxygen from rice root, which increased the quantity of bacteria, the microbial activity, and the content of MBC, MBN, and MBP significantly, in which the content of MBC increased up to a range from 33.9% (NPK) to 47.3% (NPKSi). So the capacity of delivery nutrient in microbial ecosystem was strengthened, and the function of paddy soil ecosystem was enhanced. However, although excessive application of potassium fertilizer (NPhK) for long time promoted the content of available potassium largely in paddy soil, its rice yield was not increased markedly compared to application no potassium fertilizer (NP). As a result, microbe community grew unhealthy, and the improvement of quality of paddy soil ecosystem was not significant. Accordingly, the treatment of NPKSi had the best ecological effects among all the treatments, followed by NPKM, NPhKM, and NPK. NPhK produced a negative effect. 【Conclusion】 Balanced fertilization of N, P, and K fertilizer is the effective method to improve the quality of paddy soil with K-deficiency, and the treatments of adding Si fertilizer or organic manure based on balanced application of inorganic N, P and K fertilizer have a significant effect.

A Study on Nitrate Contamination of Ground Water Sources in Areas of Protected Vegetables-Growing Fields —A Case Study in Huimin County, Shandong Province#br#

ZHANG Li-juan,JU Xiao-tang,LIU Chen-chen,KOU Chang-lin3

Scientia Agricultura Sinica. 2010, 43(21): 4427-4436 . doi:10.3864/j.issn.0578-1752.2010.21.012

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【Objective】 Huimin County in Shandong Province is a typical intensive vegetable planting area in North China Plain. The concentration of nitrate in shallow ground water in this county was analyzed and potential source of nitrate was tracked.【Method】 Multi-point collection of samples of soil, fertilizer and underground water in the vegetable planting area was made; then stable isotope technology was used to track the potential source of nitrite in groundwater. 【Result】 The result showed that the concentration of nitrate ranged from 25.3 to 279.6 mg?L-, with an average of 121.6 mg?L-1 which was about 600 times as much as that in deep well water in field. The highest concentration of nitrate in ground water was in cucumber patch, followed by celery-chili patch, chili patch, celery-cucumber patch and celery-tomato patch. In the study areas, the concentration range of δ15 N in the soil was from 1.96‰ to 7.38‰ and the concentration of chemical fertilizer (such as urea and compound fertilizer) and dung (such as farmyard manure and stable manure) ranged from 0.2‰ to 0.6‰ and from 7.3‰ to 16.87‰, respectively. The δ15 N value of ground water sample ranged from -0.01‰ to 15.91‰ with an average of 6.75‰ ±3.15‰. The value of δ15 N in ground water was not accordingly increased with the decrease of concentration of NO3-N. The results also showed that the denitrification of ground water was relatively weak in the study areas.【Conclusion】 The nitrite contamination of shallow ground water in vegetable greenhouses is extremely serious, and it is seriously influenced by humanity. The main source of nitrate is soil organic nitrogen, and the minor source is animal dung.

Construction and Composition Analysis of the Complex Microbial System CSS-1 of High Decomposition Efficiency for Corn Stalks#br#

LIU Yao,LI Li,LI Jun,GUAN Da-wei,JIANG Xin,SHEN De-long,DU Bing-hai

Scientia Agricultura Sinica. 2010, 43(21): 4437-4446 . doi:10.3864/j.issn.0578-1752.2010.21.013

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【Objective】 In order to accelerate decay of cornstalks returned to fields in Northern China, the complex microbial system CSS-1 with high efficiency and stable degrading ability for corn stalks was constructed and its microbial composition was analyzed. 【Method】 The CSS-1 was domesticated from the soils which had been treated with cornstalks for a long time in Shanxi, Shandong and Beijing using the methods of nutrition-restricted cultivation combined with gradient-temperature induction. Its decomposition ability was determined by weight-loss percentage, C/N and CMC enzyme activity of the treated corn stalks. The stability of CSS-1 was confirmed by comparing the curves of weight-loss percentage, CMC enzyme activity, xylanase activity, as well as PCR-DGGE analysis of CSS-1’s different generations. The microbial composition of CSS-1 was analyzed by cloning library method. 【Result】 The average of cellulase activity and the maximum cellulase activity produced by CSS-1 were 79% and 82% higher respectively than those of the widely used inoculant A in corn stalk decomposition experiments. The weight-loss of the corn stalks treated with CSS-1 increased by 62.62% and 173.65 % compared with that of blank control and the inoculant A, respectively. The CSS-1 had high decomposition efficiency for corn stalks and microbial composition stability was confirmed by determining and evaluating the subculture of 22 generations. The results of cloning library method showed that the dominant bacteria of CSS-1 belonged to Enterobacter sp., Cellulomonas sp., Streptomyces sp., Bacillaceae sp., Pantoea sp. and Cellvibrio sp. and the dominant fungi were Trichoderma sp. and Gibberella sp. 【Conclusion】 The complex microbial system CSS-1 has high efficiency corn-stalk decaying ability under natural conditions, and its microbial component and decomposition function are suitable for corn stalks returned to fields in Northern China.

cDNA-AFLP Analysis and Conversion of SCAR Markers of Near-Isogenic Lines with Lobed Leaves from No-Heading Chinese Cabbage (Brassica rapa ssp. cheninsis) #br#

HUI Mai-xia,WANG Han,ZHANG Lu-gang,HE Yu-ke

Scientia Agricultura Sinica. 2010, 43(21): 4447-4454 . doi:10.3864/j.issn.0578-1752.2010.21.014

Abstract ( 998 )

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【Objective】 The objective of the research was to detect the cDNA fragments of the genes related to leaf-lobed phenotype in no-heading Chinese cabbage and study its molecular mechanism. 【Method】 The study was carried out to reveal the differential expression of genes in the near-isogenic lines with lobed leaves by cDNA amplified fragments length polymorphism (cDNA-AFLP) analysis. 【Result】 There were 57 differentially expressed bands between two lines which belonged to 55 unique genes. Among them, 25 bands were associated with the NIL lines of smooth margin, while 30 bands with the NIL lines of lobed margins. Fifty-four bands had the homologous sequences in NCBI database, and only 1 band showed an unknown sequence. The genes with these homologous sequences are involved in the following biological process: metabolism, transcription, cell organization, protein synthesis and degradation, signal transduction mechanism, photosystemⅠ/Ⅱ and retrotransposon factor, etc. Furthermore, the result of AFLP-SCAR analysis was consistent with the result of cDNA-AFLP analysis. 【Conclusion】 Gene expression profiling of the near-isogenic lines with smooth and lobed leaf margins from no-heading Chinese cabbage were revealed and identified via cDNA- AFLP method, and some genes related to development of lobed leaves were proposed. The AFLP-SCAR markers are helpful for marker-assisted selection of agronomic traits with lobed leaves.

A Preliminary Study on the Flavonoids in Fruits of 22 Apple Germplasm Resources #br#

NIE Ji-yun,Lü De-guo,LI Jing,LIU Feng-zhi,LI Hai-fei,WANG Kun2

Scientia Agricultura Sinica. 2010, 43(21): 4455-4462 . doi:10.3864/j.issn.0578-1752.2010.21.015

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【Objective】 The aim of this study was to investigate the flavonoid composition and content in fruits of apple germplasm resources (AGRs), to discover AGRs rich in flavonoids, and to provide a basis for exploitation of flavonoids in fruits of AGRs and for breeding apple cultivars rich in flavonoids. 【Method】 Flavanoids in fruits of 22 AGRs were determined by RP-HPLC. 【Result】 There were 34 Flavonoids were detected (including 5 flavanols, 6 dihydrochalcones, 15 flavonols, and 8 anthocyanins), among which 18 flavonoids were not reported in fruits of apple cultivars. There were 16-30 flavonoids in fruits of 22 AGRs, of which 14 were common flavonoids. Total content of 5 flavanols detected was 10.4-2 764.9 mg?kg-, and over 1 700 mg?kg-1 in fruits of 5 AGRs. Total dihydrochalcones were 58.1-1 077.5 mg?kg-, and more than 450 mg?kg-1 in fruits of 7 AGRs. Total flavonols were 52.9-645.6 mg?kg-, and higher than 200 mg?kg-1 in fruits of 6 AGRs. Anthocyanins only exisited in red fruit, the total of which was 0.3-284.8 mg?kg-, and beyond 150 mg?kg-1 in fruits of 6 AGRs. 14 AGRs (except S, S4, S6, S10, S13, S14, S15, and S17) all had abundant flavanols included oligomeric and polymeric proanthocyanidins. There was a special flavanol (RT=42.43 min) in fruits of S18 with content of 1 350.7 mg?kg-1. S4, S6, S7, S1, and S22 were AGRs high in dihydrochalcones. S, S4, S9, S14, S17, S18, and S20 were AGRs high in flavonols. And S, S, S3, S5, S9, and S22 were AGRs high in anthocyanins. 【Conclusion】 Flavonoids in fruits of AGRs studied were very rich and showed significant diversity. There were 16 AGRs were high in flavonoids with total flavonoids (TF) above 10 000 mg?kg-1. These AGRs with abundant flavonoids can be used to exploit flavonoids in the fruit and to breed apple cultivars high in flavonoids.

Effects of Elevated CO2 on Vase Quality, Physiological and Structural Characteristics of Cut Chrysanthemum#br#

WANG Yan-li,HUANG Zhi-zhe,SUN Rui,CHEN Fa-di,TENG Nian-jun

Scientia Agricultura Sinica. 2010, 43(21): 4463-4472 . doi:10.3864/j.issn.0578-1752.2010.21.016

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【Objective】 The effects of elevated CO2 on vase quality, physiological and structural characteristics of cut chrysanthemum were investigated for the purpose of applying elevated CO2 to the fresh-keeping cut chrysanthemum and even other cut flowers. 【Method】 Cut flowers of Chrysanthemum morifolium ‘Sijihuang’ were firstly held into deionized water, and then subjected to 380 (the control) and 760 (elevated CO2) μmol?mol-1 CO2 , respectively. The changes in morphology, physiology and structure were examined using portable photosynthesis system, the technique of paraffin section, transmission electron microscopy, and some other physiological methods. 【Result】 Compared with the control, elevated CO2 increased fresh weight and flower diameter of cut chrysanthemum, retarded its senescence, and extended its vase life. In addition, compared with the control, elevated CO2 enhanced photosynthetic rate, contents of chlorophyll and soluble sugar, and activities of superoxide dismutase (SOD) and peroxidase (POD), but reduced malondialdehyde (MDA) content. Furthermore, elevated CO2 retarded cell degeneration in leaves and petals in comparison to the control. 【Conclusion】 It is possible that elevated CO2 may provide more carbohydrates for normal cell metabolism of cut flowers through directly increasing photosynthetic rate, and indirectly retarded cell degeneration by enhancing the activities of SOD and POD. As a consequence, elevated CO2 extended the life of cut flowers.

Study of Four Coating Materials of SPME Fiber on Extraction of Aroma Compounds in Strawberry#br#

FU Lei,LIU Zheng-sheng,SUN Xin-yang,ZHU Shu-hua

Scientia Agricultura Sinica. 2010, 43(21): 4473-4481 . doi:10.3864/j.issn.0578-1752.2010.21.017

Abstract ( 1115 )

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【Objective】 In this paper the extraction of strawberry aroma compounds with four coating materials of solid-phase micro-extraction (SPME) fiber and the automatic identification method for gas chromatography/mass spectrometry (GC/MS) data were researched. The aim of this experiment was to summarize a simple, accurate method for quality breeding and processing of strawberry. 【Method】 The aroma compounds in strawberry were detected by SPME-GC/MS- the automatic mass spectral deconvolution and identification system (AMDIS). 【Result】 A total of 97 compounds were identified from the sample extracts. The major constituents were esters, alcohols, ketones and terpenes, with the proportions of 42.3%, 13.4%, 10.3% and 6.2%, respectively. There are at least eight kinds of characteristic aroma components in strawberry. The most important aroma compounds were ethyl butanoate, ethyl hexanoate, linalool, furaneol, methyl butanoate, methyl hexanoate, 2-heptanone and nerolidol according to their aroma values. The 50/30 μm DVB/CAR/ PDMS fiber showed high sensitivity and selectivity for the determination of aroma compounds. The rest sequence was 100 μm PDMS,85 μm PA and 7 μm PDMS fibers in turn. Four SPME fibers had the similar extraction effect to ester. 50/30 μm DVB/CAR/PDMS fiber had significantly higher extraction effect than other fibers to ketones, terpenes, alcohols and aldehydes. 【Conclusion】 50/30 μm DVB /CAR /PDMS fiber is suitable for the extraction of aroma compounds of strawberry. The AMDIS is sensitive, accurate and rapid. It is worth to be popularized and applied.

Characterized of the Spatial and Temporal Expression of Several Sperm-Associated Antigen Genes in the Genital Tracts and Mature Sperm of Pigs#br#

SONG Cheng-yi,GAO Bo,WU Han,WANG Xiao-yan,WANG Sheng-zhi,ZHOU Hui-yun,CHEN Guo-hong,MAO Jiu-de

Scientia Agricultura Sinica. 2010, 43(21): 4482-4489 . doi:10.3864/j.issn.0578-1752.2010.21.018

Abstract ( 1029 )

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【Objective】 The aim of current study is to investigate the spatial and temporal expression profiles of several sperm-associated antigen genes (SPAG, SPAG5, SPAG6, SPAG11C and SPAG11E) in the genital tracts and mature sperm of Meishan boars and gilts. 【Method】 The RT-PCR technique was used to detect the spatial expression patterns of these genes in genital tracts and sperm, while semi-quantitative RT-PCR was used to examine the temporal expression of each gene in testis. 【Result】 Five genes presented different expression patterns in the genital tracts of Meishan boars and gilts, and SPAG1 gene expression was the highest in testis, moderate in seminal vesicle, prostate, corpus epididymis, uterine horn and oviduct, weak in cauda epididymis, cervix and ovary. SPAG5 expressed mainly in testis and weakly in prostate, corpus epididymis and cervix. While the expression of SPAG6 was the highest in testis, moderate in oviduct and weak in uterine horn. SPAG11C expressed highly in corpus epididymis and testis, whereas SPAG11E expressed weakly in corpus and cauda epididymis. Only SPAG11E mRNA expression in mature sperm was detected. The RT-PCR analysis of the temporal expression of SPAG, SPAG5, SPAG6 and SPAG11C genes in testis revealed that, in general, the expression of all genes examined elevated with age increase but with some variance. The expression of SPAG1 and SPAG11C presented similar trend, and it was low on days 1 and 30, but it increased significantly on days 60, 90 and 150 (P＜ 0.05). The mRNA expression of SPAG5 was relatively low on days 1 and 30 as well, but increased significantly on days 60 and 90 (P＜0.05), then decreased slightly on day 150. The mRNA expression of SPAG6 was low on days 1 and 30, increased significantly on day 60 (P＜0.05) and maintained to day 90, but decreased significantly on day 150 (P＜0.05). 【Conclusion】 The expression of SPAG, SPAG5, SPAG6, SPAG11C and SPAG11E in genital tracts was more extensive, weak expression of SPAG11E was detected in mature sperm, and the temporal expression of these genes was paralleled with the sexual development.

Effects of Dietary Supplementation of Acanthopanax senticosus Extracts on Weanling Stress in Piglets #br#

YAN Fu-yong,YIN Yu-long,KONG Xiang-feng,YIN Fu-gui,YANG Feng,ZHANG Yu-zhe

Scientia Agricultura Sinica. 2010, 43(21): 4490-4496 . doi:10.3864/j.issn.0578-1752.2010.21.019

Abstract ( 847 )

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【Objective】 The study was conducted to test the hypothesis that dietary supplementation of Acanthopanax senticosus extracts (ASE) inhibits weanling stress in piglets. 【Method】 Ninety-six piglets weaned at 21 day of age were randomly divided into 3 treatment groups with 4 replicates for each by weight and sex to investigate the growth performance, serum biochemical parameters and hormone levels correlated to growth. Another 6 male piglets were selected to investigate the apparent digestibility of nutrients with 2× 3× 3 Latin square design. The piglets were fed basal diet suplemented with 0, ASE or antibiotics, respectively. 【Result】 ASE significantly increased the ADG, improved the gain-feed ratio in comparison with the basal diet group. Apparent digestibility of Ca, TE and P in the ASE group was higher than that of basal diet group. ASE increased the serum contents of LDL, CHO, GLU and the activity of ALP, decreased the content of SUN, and significantly increased the serum contents of FT3, FT4, GH, IGF-1 and FT3/FT4 in comparison with the basal group. 【Conclusion】 The findings showed that ASE as a dietary additive can modulate hormone levels, elevate the digestion and metabolism, thereby inhibit weanling stress and improve growth performance.

Cloning of Thymosin β 4 Gene from Inner Mongolia Cashmere Goat and Its Stable Transfection into Caprine Fetal Fibroblasts Cells#br#

WANG Yan-feng,LIANG Yan,JIN Yong,WANG Xiao-jing,GUO Xu-dong,WANG Wei,WANG Xiao,WANG Zhi-gang,LIU Dong-jun

Scientia Agricultura Sinica. 2010, 43(21): 4497-4504 . doi:10.3864/j.issn.0578-1752.2010.21.020

Abstract ( 1109 )

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【Objective】 The objective of the experiment is to clone the thymosin beta 4 (Tβ4) gene from Inner Mongolia Cashmere Goat and then construct a skin-follicle-cell-specific expression vector pCDsRed-KT. The vector was transferred into goat fetal fibroblasts Cells (GFb) to obtain a transgenic cell line, which stably expresses red fluorescence. The transgenic cell line can be used for nuclear transplantation. 【Method】 Tβ4 gene was cloned by RT-PCR. Then pCDsRed-KT, a skin-follicle-cell-specific expression vector of Tβ4, was constructed by connecting with KAP6-1 promoter, as well as a pCDsRed2 expression unit. The Inner Mongolia Cashmere Goat fetal fibroblast (GFb) cells were transfected with the expression vector by lipofectamineTM2 000. Cell clones stably expressing red florescence were obtained after screening by G418. The recombinant of extrogenous DNA was identified by polymerase chain reaction. 【Result】 The cloned Tβ4 gene cDNA from Inner Mongolia Cashmere Goat was 142bp in length, including an ORF of 135bp and encoding an active peptide which formed by 44 amino acids. The amino acid sequence shares 100% identity with the bovine Tβ4 (XM002706880.1). The sequencing result showed that the Tβ4 gene was connected properly to the downstream of pKAP6-, then the CMV promoter and the DsRed2 gene in sequence. Identification of the transgene in the cell clones was examined by PCR and the exogenous DNA (pKAP6-1 and Tβ4 gene) had been integrated into genome. The stably transfected cell line could express the red fluorescence efficiently. 【Conclusion】 The Tβ4 gene was cloned and a skin-follicle-cell-specific expression vector of Tβ4 was constructed successfully .The exogenous genes have been integrated into GFb cells genome stably. These results have paved the way to obtain the transgenic sheep by nuclear transfer in the future.

Proteome Comparison Analysis of Sexually Matured Drone and Adult Worker Honeybee Antennae#br#

SONG Fei-fei,WU Jing,FANG Yu,FENG Mao,ZHENG Ai-juan,LI Jian-ke

Scientia Agricultura Sinica. 2010, 43(21): 4505-4513 . doi:10.3864/j.issn.0578-1752.2010.21.021

Abstract ( 1000 )

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【Objective】 The goal of this study is to gain better understanding in molecular basis between sexually matured drone and adult worker through differential proteome analysis of their antennae quality and quantity. 【Method】 Two-dimensional gel electrophoresis (2-DE) were run to identify the protein in drone and worker antennae with their molecular weight and pI and expression volume. Accordingly, several proteins with significant variations in their expression volume were identified by using MALDI-TOF/MS and MASCOT software. In addition, hierarchical cluster analysis of the identified proteins was conducted. 【Result】In total, 484 and 479 protein spots were detected in adult drone and worker antennae, respectively, of which 416 expressed proteins were shared between drone and worker antennae. There were 102 and 80 proteins spots upregualted in drone and worker antennae, respectively. Nine proteins spots significantly altered their expression were identified and classified into transport, energy metabolism, hormone metabolism, and a unknown functional group. An odorant binding protein 14, fatty acid binding protein (couple), juvenile hormone esterase (couple), acyl-CoA dehydrogenase, bellwether isoform , CG31974-PA were expressed highly in the antennae of sexually matured drone. An antennal special protein 2 was expressed highly in the antennae of adult worker. 【Conclusion】 Most of the protein spots were commonly expressed in the antennae of the two castes, indicating both castes of honeybees are conservative during molecular evolution through their antennae. Transport and metabolism related proteins were highly expressed in drone antennae indicating they are crucial in assisting the drones to discriminate sex pheromone and chase the queen to make successful mating exactly and swiftly. Antennal special protein 2 was expressed highly in worker antennae which is likely to help the foragers to search nectar resource quickly and recognize its nest mate through receiving colony pheromone.

Observation of Duckling Immune Injury Caused by Duck-Origined Reovirus Infection#br#

LI Shuang,GU Chang-qin,BAI Jia-yuan,ZHANG Hong,ZHANG Wan-po,CHENG Guo-fu,HU Xue-ying

Scientia Agricultura Sinica. 2010, 43(21): 4514-4520 . doi:10.3864/j.issn.0578-1752.2010.21.022

Abstract ( 759 )

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【Objective】 The pathological damages of spleen and bursa of Fabricius in ducklings caused by duck-deprived reovirus and related immune index were observed. The mechanisms of immune organ damage and immune suppression upon duck-derived reovirus infection were studied for providing a theoretical basis for further studies on pathogenesis and immune prevention and control. 【Method】 Cherry Valley ducklings at 7-day old of age were artificially infected with duck-derived reovirus, then histopathological changes of spleen and bursa of Fabricius were observed. Spleen and bursa index, the positive rate of CD3+, CD8+ T cells in peripheral blood,and IgY-producing cells of spleen and bursa of Fabricius were detected. A significant difference between experimental and control group was analyzed. 【Result】 After the infection of duck-derived reovirus, notable necrosis was found in duckling spleen, followed by granuloma structure, and lymphoid follicles on lamina propia decreased significantly. The spleen and bursa indexes were reduced. The positive rate of CD3+, CD8+ T cells in peripheral blood also decreased. IgY -producing cells increased in spleen but decreased in bursa of Fabricius. 【Conclusion】 Duckling-origined reovirus infection may lead to severe injury of the ducklings immune organs and induce mmune suppression.

Sequence Characteristics, Prokaryotic Expression as Well as Antigenicity Detection of the Truncated UL53 Gene of Duck Enteritis Virus#br#

ZHANG Shun-chuan,XIANG Jun,CHENG An-chun,WANG Ming-shu,LI Li-juan,LI Xin

Scientia Agricultura Sinica. 2010, 43(21): 4521-4528 . doi:10.3864/j.issn.0578-1752.2010.21.023

Abstract ( 932 )

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【Objective】 Applying the strategy to select the main antigenic domains of DEV-UL53 gene and carry out multiparameter B cell epitope prediction of DEV-truncated UL53 gene, to express efficiently the DEV-truncated UL53 gene and analyze the antigenicity of this fussion protein by Western blot. 【Method】 The bioinformatics software DNAStar Protean was used to predict the main antigenic domains of gK protein coded by DEV-UL53 gene, then the truncated UL53 gene corresponding the main antigenic domains was selected and used to predict the secondary structure, flexibility domains, surface possibility with DNAStar software and predict hydrophilicity as well as transmembrane domains on-line, meanwhile clone, subclone as well as prokaryotic expression of the truncated UL53 gene, also the antigenicity of the fussion protein was detected by Western blot. 【Result】 The B cell epitopes of gK coded by DEV-truncated UL53 gene most likely distribute in Ala20—Leu25, Ser40—Met47, Leu68—Ile78, Val124—Phe128, Ile129—Tyr134, Asp176—Ile178. The recombinant expression plasmid was transformed into BL21 and expressed under the induction of IPTG. Western blot analysis indicated that polyclonal rabbit antiserum against DEV had specific reaction with the fussion protein. 【Conclusion】 DEV-truncated UL53 gene was efficiently expressed in prokaryotic system and also the gK fussion protein has good reactionogenicity, which provided useful data for research of the UL53 gene, gK protein and development of new generational vaccine and diagnostic reagent.

Expression of the Chicken Antibacterial Peptide Fowlicidin-3 in Pichia Pastoris and Identification of Biological Activity#br#

LI Rong-rong,HE Zhen-quan,BAO En-dong,CHEN Pu-yan

Scientia Agricultura Sinica. 2010, 43(21): 4529-4535 . doi:10.3864/j.issn.0578-1752.2010.21.024

Abstract ( 994 )

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【Objective】 The biological property of the recombinant antibacterial peptides Fowlicidin-3 and its application in animal husbandry were studied. 【Method】 According to the amino acid sequences of Fowlicidin-3 as described in the antibacterial peptide database, using the preferential condon of P. pastoris, the antibacterial peptide Fowlicidin-3 gene 114 bp in length was designed and synthesized by SOE PCR. The antibacterial peptide gene was cloned into the pPICZα-A vector to construct the recombinant expression vector pPICZα-A-F. The linearized plasmid pPICZα-A-F was transformed into P. pastoris X-33 by electroporation to construct the recombinant expression yeast strain. 【Result】 Fowlicidin-3 was successfully expressed and the concentration of the secreted antibacterial peptides reached up to 170 mg?L-1. Agrose diffusion assay showed that antibacterial peptide Fowlicidin-3 exhibited strong antibacterial abilities to E. coli K99 and Salmonella pullorum, the diameter of inhibition zone to E. coli K99 and Salmonella pullorum were 1.9 cm and 2.2 cm, respectively. The result also showed that the recombinant antibacterial peptides Fowlicidin-3 could be expressed and obtained with high level while the pH of the culturing BMMY medium was 6.0, the yeast was cultured under 29℃ for 72 hours and 2% methanol was supplemented into the medium. 【Conclusion】 The high level expression of antibacterial peptide Fowlicidin-3 with great biological activities was successfully constructed in yeast strain P. pastoris in this research.

Effects of Integrated Nutrient Management on Lodging Resistance of Rice in Cold Area#br#

ZHANG Ming-cong,LIU Yuan-ying,LUO Sheng-guo,PENG Xian-long,CHEN Li-nan,LI Zong-yun,LI Jia

Scientia Agricultura Sinica. 2010, 43(21): 4536-4542 . doi:10.3864/j.issn.0578-1752.2010.21.025

Abstract ( 795 )

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【Objective】 The relationship between integrated nutrient management and the lodging resistance of rice was studied to elucidate the mechanism underlying the lodging resistance of rice plant in cold area. 【Method】 A field experiment was conducted with 4 nutrition managements and the physical properties, mechanical features and carbon-nitrogen ratio of the stems of rice were analyzed. 【Result】 The yield of the farmers fertilization practice (FFP) was 8.55 t?hm-2. Optimal fertilization practice (OPT) increased the yield, reduced the length of the first and second internode of the basal stem by 11.6% (P＜5%), 13% and 6% (P＜5%), respectively, significantly increased carbon-nitrogen ratio, stem diameter, stem wall thickness, leaf sheath weight and area of cross section 30 d after heading, and reduced the index of lodging resistance by 14.18% (P＜5%). Compared to FFP, the yield of the farmers fertilization practice for high yield (FFP -H) was increased by 15.2% and achieved high-yield rice. Compared to FFP-H, the optimal fertilization practice for high yield (OPT-H) increased rice yield by 7.4%, the length of the first and second internode of the basal stem is reduced by 12% and 4% (P＜5%), separately, at the same time, carbon-nitrogen ratio, stem diameter, stem wall thickness, leaf sheath weight and area of cross section were significantly increased, and the index of lodging resistance was reduced by 6.19% (P＜5%) 30 d after heading. Compared to OPT, the harvest panicles of OPT-H was increased by 15.1% (P＜5%), yield was increased by 10.9% (P＜5%), but the index of lodging resistance between the two treatments was not significanty different. 【Conclusion】 OPT and OPT-H increased the height of gravity center and plant height, but reduced the distance of basal internode due to optimization of internode collocation of rice, and increased carbon-nitrogen ratio of rice stems and stem diameter, promoted stem substantiality, resulting in high grain yield and lodging resistance of rice plant.

Effect of Nitrogen Application Rate on Cooking and Eating Qualities of Different Growth-Development Types of Japonica Rice#br#

GAO Hui,MA Qun,LI Guo-ye,YANG Xiong,LI Xue-qiao,YIN Chun-yuan,LI Min,ZHANG Qing,ZHANG Hong-cheng,DAI Qi-gen,WEI Hai-yan

Scientia Agricultura Sinica. 2010, 43(21): 4543-4552 . doi:10.3864/j.issn.0578-1752.2010.21.026

Abstract ( 1080 )

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【Objective】 The change rule of cooking and eating qualities of three growth-development types of Japonica rice varieties was studied. 【Method】 A field experiment was carried out with 50 Japonica rice varieties of three growth-development types adopted in the region of Yangtze River, to study the effects of four nitrogen levels (zero, low, medium and high) on the difference in cooking and eating qualities. Variety difference of taste value in response to nitrogen levels was also discussed and their types were also classified. 【Result】 The main results showed that in the range of 0-300 kg?hm-, with the level of nitrogen increased, the amylase content, gel consistency and taste value of Japonica rice varieties decreased. The taste value and amylase content increased with extension of the growth duration, and the effect on gel consistency was on the contrary. All the 50 rice cultivars could be classified into three types (insensitive, intermediate and sensitive) in terms of their different responses of taste value to nitrogen application levels. And two rice groups among them were also recommended. One group was the varieties with high and stable taste value under all nitrogen levels, the other group was the varieties which were sensitive to nitrogen application levels, and good cooking quality could be obtained through proper reducing nitrogen application. 【Conclusion】 In the range of 0-300 kg?hm-, with the nitrogen level increased the amylase content and gel consistency of Japonica rice varieties decreased. The sensitivity of rice taste value to nitrogen fertilizer is different among varieties.

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