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    10 May 2007, Volume 21 Issue 3 Previous Issue    Next Issue

    研究报告
    研究简报
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    研究报告
    Molecular Cytogenetic Analysis of a Spontaneous Interspecific Hybrid Between Oryza sativa and Oryza minuta
    YI Chuan-deng ,LIANG Guo-hua ,GONG Zhi-yun ,YU Heng-xiu ,TANG Shu-zhu ,YAN Chang-jie ,GU Ming-hong
    2007, 21(3): 223-227 . 
    Abstract ( )   PDF (157KB) ( )  
    Genomic in situ hybridization(GISH) is a powerful tool to characterize parental chromosomes in interspecific hybrids,including the behaviour of autosynapsis and chromosome pairing,which could be used to distinguish the chromosomes of O.sativa from wild species in a spontaneous interspecific hybrid.The chromosome pairing in meiotic metaphase Ⅰ of the hybrid between O.sativa and O.minuta was investigated by GISH.The hybrid was a triploid with 36 chromosomes according to the chromosome number investigated in mitosis of root tips.In meiotic metaphaseⅠof the hybrid,less chromosome pairing was observed and most of the chromosomes existed as univalents.Based on GISH analysis,the chromosomes of the hybrid were composed of genomes A,B and C.So it was believed that the hybrid was the result of natural hybridization between cultivated rice Oryza sativa and wild species O.minuta which was planted in experimental fields.
    Identification and Fine Mapping of a Gene Related to Pale Green Leaf near Centromere Region in Rice(Oryza sativa L.)
    ZHU Li ,LIU Wen-zhen ,WU Chao ,LUAN Wei-jiang ,FU Ya-ping ,HU Guo-cheng ,SI Hua-min ,SUN Zong-xiu
    2007, 21(3): 228-234 . 
    Abstract ( )   PDF (293KB) ( )  
    A thermo-insensitive pale green leaf mutant(pgl2) was isolated from T-DNA inserted transgenic lines of rice(Oryza sativa L.subsp.japonica cv.Nipponbare).Genetic analysis indicated that the phenotype was controlled by a recessive mutation in a single nuclear-encoded gene.To map the PGL2 gene,an F2 population was constructed by crossing the mutant with Longtefu(Oryza sativa L.subsp.indica).The PGL2 locus was roughly linked to SSR marker RM331 on chromosome 8.Therefore,14 new INDEL markers were developed around the marker.PGL2 gene was further mapped to a 2.37 Mb centromeric region.There was no obvious difference between the mutant and wild type in total chlorophyll content of rice leaves,while the ratio of Chl a/Chl b in the mutant was only about 1,distinctly lower than that in the control,which suggested that the PGL2 gene was related to the transformation between Chl a and Chl b.Moreover,the method of primer design around the centromeric region was discussed,which would provide insight into fine mapping the functional genes in plant centromeres.
    RiceDB:a Web-Based Integrated Database for Annotating Rice Microarray
    HE Fei ,SHI Qing-yun ,CHEN Ming ,WU Ping
    2007, 21(3): 235-241 . 
    Abstract ( )   PDF (497KB) ( )  
    RiceDB,a web-based integrated database to annotate rice microarray in various biological contexts was developed.It provides convenient query for comprehensive and auto-updated annotation compared with other similar databases.It is composed of eight modules.RiceMap module archives the process of Affymetrix 57K probe sets mapping to different databases about rice,and aims to the genes represented by a microarray set by retrieving annotation information via identifier or accession number of every database;RiceGO module indicates the association between a microarray set and gene ontology categories consisting of biological process,molecular function and cellular component;RiceKO module is used to annotate a microarray set based on the KEGG biochemical and regulatory pathways;RiceDO module indicates the information of domain associated with a microarray set;RiceUP module is used to obtain promoter sequences for all genes represented by a microarray set;RiceMR module lists potential microRNA which regulated the genes represented by a microarray set;RiceCD is used to annotate the genes represented by a microarray set in the context of chromosome distribution;RiceGF is used to annotate the genes represented by a microarray set in the context of rice paralogous gene family distribution.
    Cloning and Identification of a Pathogenicity-Related Gene xopXoo in Rice Pathogen Xanthomonas oryzae pv.oryzae
    YANG Juan ,XU Yun-he ,ZOU Li-fang ,CHEN Gong-you
    2007, 21(3): 242-246 . 
    Abstract ( )   PDF (842KB) ( )  
    The xopX gene from Xanthomonas campestris pv.vesicatoria(Xcv) is involved in hypersensitive response induction in nonhost tabacco and enhances the susceptibility of host pepper.However,the function of the homolog with xopX revealed by the genome sequence of X.oryzae pv.oryzae(Xoo) strains MAFF311018 and KACC10311 is uncertain.To study the function of xopX homolog in Xoo,a xopXoo gene of Xoo was cloned and mutated.The xopXoo mutant induced hypersensitive response in tobacco and water soaking symptoms in rice seedlings,but its pathogenicity and reproductive capacity decreased greatly in rice leaves.Complementation of the xopXoo mutant with the xopXoo gene recovered the bacterial growth and the ability to cause the lesion length to the wild type,suggested that the xopXoo gene was related to the pathogenicity of Xoo in rice.Moreover,the products of putative genes possibly eliciting hypersensitive response in tobacco were postulated.
    QTL Analysis for Flag Leaf Morphological Traits in Rice(Oryza sativa L.) Under Different Genetic Backgrounds
    PENG Mao-min ,YANG Guo-hua ,ZHANG Jing-jing ,AN Bao-guang ,LI Yang-sheng
    2007, 21(3): 247-252 . 
    Abstract ( )   PDF (1091KB) ( )  
    Zhaiyeqing 8×Jingxi 17 doubled haploid(DH) population and Zhenshan 97×Minghui 63 recombinant inbred line(RIL) population were employed to dissect the genetic basis of the flag leaf morphological traits including length,width,the ratio of length to width,area,and perimeter by using composite interval mapping approaches.The traits were normally distributed with transgressive segregation in both directions,which showed that these traits were controlled by minor polygenes.The significant positive correlation was detected between different traits.In the DH(Zhaiyeqing 8×Jingxi 17) population,eight intervals carrying quantitative trait loci(QTLs) on four chromosomes were identified for the four traits.Two QTLs affected length,perimeter and area of leaf simultaneously.In the RIL(Zhenshan 97×Minghui 63) population,16 intervals carrying QTLs on five chromosomes were identified for the five traits.Among these QTLs,there were one common QTL for length,perimeter and the ratio of length to width,two common QTLs for width and area,one common QTL for length and perimeter,and one common QTL for length,perimeter and area,respectively.These results suggested that there were significant differences in QTLs in different populations.Moreover,there were some common QTLs for the closely relative traits at the same or near chromosome regions.
    Phenotypic and Genetic Characterization of a Twin-ovary Mutant(TOR) in Rice
    WEN Wen ,LI Shuang-cheng ,WANG Shi-quan ,HE Ti-hong ,LI Ping
    2007, 21(3): 253-258 . 
    Abstract ( )   PDF (1643KB) ( )  
    A rice floral mutant with twin-ovary and dwarf plant was isolated from the progenies of the combination of C2/Mianxiang 5B.By anatomical observations,the mutant was characterized with the phenotypes of fewer stamens,more pistils and stigmas,twin-ovary,malformed embryo sac,as well as stamen-originated pistils.Due to its exceeding sterility,the mutation was maintained by heterozygotes,and it was also inherited stably after five generations of self-pollination.The segregation ratio of wild type plants to mutant plants in the population degenerated from heterozygotes was 3∶1,indicating that the mutant is controlled by a single recessive gene,and designated tentatively as TOR.
    Discovery of a Rapid Leafing Genotype at Vegetative Growth Stage in Rice and Its Preliminary Analysis
    PAN Cun-hong ,CHEN Zong-xiang ,MAO Hai-yan ,ZHANG Ya-fang ,ZUO Shi-min ,CHENG Jin-rong ,PAN Xue-biao
    2007, 21(3): 259-264 . 
    Abstract ( )   PDF (161KB) ( )  
    The leafing rate of fourteen cultivars were estimated based on the interval sowing experiments and the rapid leafing genotype at the vegetative growth stage in an indica cultivar Yanhui 559 was discovered.The leaf number of the main culm in Yanhui 559 was 4-5 more than that in Lemont,moreover the leafing rate of Yanhui 559 was significantly higher than that of Lemont on the basis of almost the same growth duration from sowing to heading.Furthermore,it showed difference in the leafing rate at the vegetative growth stage,but not at the panicle initiation stage.According to the analysis on the leafing rate of the parents(Yanhui 559,Lemont),two backcross populations and F2 plants,it was suggested that several quantitative trait genes possibly including main effect members regulated the rapid leafing character.The investigation on the traits of parents and partial populations showed that the rapid leafing genotypes exhibited more tillers per plant,higher initial tillering rate and maximum tiller number per plant,and its yield components including number of panicles per plant and number of grains per panicle were superior to the slow leafing types.The necessity of further research on the genotype and its prospects in rice breeding were discussed.
    Utilizing Early Generation Stability Characteristic to Breed Restorer Line of Hybrid Rice
    ZHOU Li-jun ,WANG Li ,WEI Qin ,AO Guang-hui ,WU Xian-jun ,LI Shi-gui
    2007, 21(3): 265-269 . 
    Abstract ( )   PDF (126KB) ( )  
    Screening elite restorer lines is one of the key points to improve the grain yield and rice quality in hybrid rice breeding.The traditional method of the restorer line breeding is characterized by time-consuming and low efficiency,and it should take 5 to 8 years to get a restorer line.By crossing the early generation stability rice with an important restorer line Shuhui 527,three stable lines(2371,409 and 2441) were obtained in F2 populations.Meanwhile,the restoration of the two lines(2371 and 409) were confirmed by molecular marker assisted selection(MAS).It was found that line 2371 had strong restoration ability and its two hybrid combinations showed obvious heterosis.The method by utilization of early generation stability characteristic and MAS showed time-saving(1-2 years) and high efficiency for breeding a new restorer line.
    Evaluation and Application of Two High-Iron Transgenic Rice Lines with a Pea Ferritin Gene
    YE Hong-xia ,GUO Ze-jian ,SHU Qing-yao ,XU Xiao-hui ,BAO Jin-song ,SHEN Sheng-quan
    2007, 21(3): 270-274 . 
    Abstract ( )   PDF (39KB) ( )  
    A total of 105 transgenic rice lines independently transformed with a pea ferritin gene(Fer) were previously obtained.After seven generations of self-crossing and GUS marker assisted selection,82 homozygous transgenic rice lines were used to evaluate their potential applications as high-iron rice germplasm.Two high-iron transgenic rice lines Fer34 and Fer65,with the iron content in the milled rice 4.82 and 3.46 times of the wild parent Xiushui 11 were identified.Further analysis indicated that the exogenous Fer gene was highly expressed,and inherited as a single locus.The transgene had no negative effect on the agronomic traits of rice plants,other mineral nutritional components,appearance and eating quality of the milled rice,indicating that they were elite high-iron breeding lines.Furthermore,the practical application and further studies facilitating utilization of the two elite breeding lines were discussed.
    Changes in Activities of Three Enzymes Degrading Galactomannan During and Following Rice Seed Germination
    REN Yan-fang ,HE Jun-yu ,WANG Xiao-feng
    2007, 21(3): 275-280 . 
    Abstract ( )   PDF (157KB) ( )  
    In order to investigate the relationships among β-mannanase,β-mannosidase and α-galactosidase required for degrading galactomannan in cell wall during and following rice seed germination,the activities of the three enzymes and the effects of ABA and GA3 on them were detected.The activities of β-mannosidase and α-galactosidase were detected in dry and non-germination rice seeds,and increased slowly during and following germination.However,the activity of β-mannanase was detected only after germination.GA3 could promote the activities of β-mannanase and α-galactosidase and ABA had little effect on the activities of β-mannanase and α-galactosidase,but inhibited seriously the activity of β-mannanase.

    Heterosis on Plant Morphology of Yongyou 6,an indica-japonica Inter-subspecific Super High-Yielding Hybrid Rice
    MA Rong-rong ,XU De-hai ,WANG Xiao-yan ,YU Sheng-miao ,JIN Qian-yu ,OUYANG You-nan ,ZHU Lian-feng
    2007, 21(3): 281-286 . 
    Abstract ( )   PDF (481KB) ( )  
    According to the results of the experiments conducted in 2003-2005,Yongyou 6,a late season inter-subspecific hybrid rice combination derived from a japonica cytoplasmic male sterile line Yongjing 2A and an indica restorer line K264806,performed high yielding potential,which was closely related to its outstanding heterosis in plant morphology over the japonica inbred rice Xiushui 63 and indica hybrid rice Shanyou 63.At the early growth stage,the tiller number of Yongyou 6 was between that of Shanyou 63 and that of Xiushui 63,and it showed a moderate tillering ability and less non-effective tillers.At the middle growth stage,the culms,sheaths and leaves of Yongyou 6 grew faster with higher biomass.The population of Yongyou 6 had better light distribution in its canopy because of its three top upright,longer and cured leaves.At the late growth stage,although Yongyou 6 was of high plant,but it perfected very strong tolerance to lodging due to its long and closed sheathes and short and thick basal internodes.At the maturity stage,Yongyou 6 showed arc-shaped panicles with more primary and secondary branches.The grain density of panicle was moderate with more oblate grains.The root-shoot ratio of Yongyou 6 was very higher at the whole growth stage.Moreover,the ideo-plant morphology of indica-japonica inter-subspecific super high-yielding hybrid was also discussed.
    Analysis on Dry Matter Production Characteristics of Middle-Season indica Super Hybrid Rice
    WU Wen-ge ,ZHANG Hong-cheng ,QIAN Yin-fei ,CHENG Ye ,XU Jun ,WU Gui-cheng ,ZHAI Chao-qun ,HUO Zhong-yang ,DAI Qi-gen
    2007, 21(3): 287-293 . 
    Abstract ( )   PDF (141KB) ( )  

    Six middle-season indica hybrid rice combinations(Shanyou 63 as CK) were used as experimental materials to study dry matter production characteristics of super hybrid rice.There were great advantages for super rice in dry matter production and accumulation and its yield rose as the increase of dry matter accumulation.Grain yield was not significantly correlated with dry matter accumulation before elongation stage,while significantly positively correlated(P<0.05) from elongation to heading stage and significantly positively correlated(P<0.01) from heading to maturity stage.There were more dry matter in vegetative organs at the heading stage in super rice but its contribution to yield was less than 148.5 kg/hm2 averagely(apparent translocation percentage was 2.5% lower than that of the control Shanyou 63).Along with the increase in leaf area index and leaf area duration,the crop growth rate rose.The mean of crop growth rate in super rice was 4542(m2·d)/hm2,higher than that of CK after transplanting.

    Effects of Different N Forms on Root Morphology and Water Absorption of Lowland and Upland Rice Plants
    LI Yong ,ZHOU Yi ,GUO Shi-wei ,SHEN Qi-rong
    2007, 21(3): 294-298 . 
    Abstract ( )   PDF (586KB) ( )  
    A hydroponic experiment was conducted to study the effects of different N forms on root growth and water Absorption of lowland and upland rice plants.Root dry weights of lowland and upland rice plants supplied with ammonium nutrition were lower than those with nitrate nutrition,while the amount of root bleading sap and water absorption per root surface area were higher in the plants supplied with ammonium nutrition than in those with nitrate nutrition.It was demonstrated that the aquaporin pathway of water absorption is the main approach of lowland and upland rice roots supplied with three different N forms,but the capacity of aquaporin for water transportation in lowland and upland rice roots was higher in ammonium nutrition than in nitrate nutrition.Moreover,upland rice was more adaptive to nitrate supply than lowland rice.
    Effects of Silicon Fertilizer Rate on Yield and Quality of japonica Rice Wuyujing 3
    ZHANG Guo-liang ,DAI Qi-gen ,WANG Jian-wu ,ZHANG Hong-cheng ,HUO Zhong-yang ,LING Li ,WANG Xian ,ZHANG Jun
    2007, 21(3): 299-303 . 
    Abstract ( )   PDF (83KB) ( )  
    The effects of silicon fertilizer rates on yield and quality of rice grain were studied with a mid-season japonica rice cultivar Wuyujing 3.With the increase of Si application rate,number of panicles per plant,number of grains per panicle,1000-grain weight and grain yield increased firstly and then decreased within the range of Si application rate of 0-450 kg/hm2,while milled rice rate and consistence showed a tendency to increase,and head rice rate increased significantly.The curves of RVA profile decreased,and amylose content,peak viscosity,hot viscosity,cool viscosity,peak time had the trend of descent,while setback decreased firstly and then increased.Meanwhile,brown rice rate and transparency had no obvious difference in the treatments.but proper Si rates decreased the chalky grain rate,chalkiness area and chalkiness,and increased protein content,gel consistency and breakdown.Considering the grain yield and quality together,225 kg/hm2 of Si fertilizer rate was suitable.

    Genetic Diversity among Populations as Related to Pathotypes for Magnaporthe grisea in Hunan Province
    LI Ya ,LIU Er-ming ,DAI Liang-ying ,LI Cheng-yun ,LIU Lin
    2007, 21(3): 304-308 . 
    Abstract ( )   PDF (152KB) ( )  
    The genetic diversity of 230 monoconidial isolates of Magnaporthe grisea was analyzed using eight pairs of SSR markers.All isolates tested were classified into seven genetic lineages at 0.23 level of the genetic dissimilarity through the clustering analysis of UPGMA.The lineages Ⅰ,Ⅴ,Ⅵ were the predominant ones with the rates of 23.9%,23.5%,23.0% respectively.Only one isolate fell into the lineage Ⅳ and five isolates belonged to the lineage Ⅶ.As 77 isolates selected from above monoconidial isolates were characterized with seven Chinese differential varieties,they were distributed to the 7 groups(ZA,ZB,ZC,ZD,ZE,ZF,ZG) and 30 pathotypes.There was great differentiation among ZA,ZB and ZC groups.ZG1 was the predominant race,and its frequency in the total blast fungus population was as high as 26.5%.Compared with the results of SSR analysis and pathotypes,there wasn’t obviously corresponding relationship between genetic lineages and pathotypes.
    Effect of Host Plant on Relationship Between Number and Total Length of Feeding Scars of the First Generation Adults of Rice Water Weevil in Fields
    CAI Xue-tao ,ZHENG Yong-min ,SHANG Han-wu ,YANG Qiong ,TANG Qi-yi ,ZHENG Xue-hao ,CHENG Jia-an ,ZHU Zeng-rong
    2007, 21(3): 309-315 . 
    Abstract ( )   PDF (151KB) ( )  
    The relationship between the number and the total length of feeding scars of the first generation adults of the rice water weevil(RWW),Lissorhoptrus oryzophilus Kuschel(Coleoptera: Curculionidae) was analyzed in field experiments during 2004 and 2005.The feeding scars on the barnyardgrass(Echinochloa crus-galli L.) leaves overnumbered those on leaves of rice,Cyperus difformis and Leersia herxandra.All 16 couples of relationships between the number and the total length of feeding scars for combinations of 2 host plant species and 2 transplanting dates,4 different species with 2 measurements respectively,were significantly positive linear.The plant species had significant effect on the regression coefficients,with the highest one on barnyardgrass.Such linear regression was robust for rice and barnyardgrass with different transplanting dates,but was not stable for different measure dates in most cases.The regression approach could be used for preliminary quantitatively inference of total feeding(and then density) of RWW at the early stage of invasion in a newly RWW invaded habitat,for evaluation of RWW resistant rice germplasm,and for test of host plant specificity in selection of biocontrol candidate agents of alien invaded weeds.
    Some Physiological Changes of Rice Plants Damaged by Striped Stem Borer,Chilo suppressalis
    XU Hong-xing ,LU Zhong-xian ,JIANG Xue-hui ,YU Xiao-ping ,CHEN Jian-ming ,ZHENG Xu-song
    2007, 21(3): 316-318 . 
    Abstract ( )   PDF (113KB) ( )  
    Some physiological changes in chlorophyll content,root activity and potassium uptake ability of rice plants infested by the larvae of the striped stem borer(SSB),Chilo suppressalis,were determined by using different rice varieties including indica hybrid rice Shanyou 63,indica super high-yielding hybrid rice Liangyoupeijiu and japonica rice Xiushui 11.Results showed that the chlorophyll content in tillers of dead-heart plants damaged by the SSB larvae decreased in all the three tested varieties,however there were no obvious difference between the damaged and healthy plants.The root activities of Shanyou 63 and Liangyoupeijiu increased while that of Xiushui 11 decreased in damaged plants.After being labeled with rubidium for 24 and 48 h,the content of rubidium in the dead-heart tillers of Shanyou 63 and Liangyoupeijiu were higher than that in tillers of the healthy plants,however the contrary trends were observed in Xiushui 11.It implied that the damage by the SSB enhanced the potassium uptake ability of the indica and super high-yielding hybrids and their compensation abilities were significantly higher compared to japonica rice Xiushui 11.
    Inhibitory Effects of Mixed-Planting of Rice Varieties with Different Weed-Tolerant Potentials on Echinochloa crus-galli
    HAN Hao-hua ,ZHOU Yong-jun ,CHEN Xin ,YU Liu-qing
    2007, 21(3): 319-322 . 
    Abstract ( )   PDF (131KB) ( )  
    Pot and field experiments were conducted to study the effects of mixed-planting of different rice varieties on germination and growth of barnyardgress(Echinochloa crus-galli var.mitis).Rice varieties Xiushui 63(allelopathic index 0.24,low competitive),PI312777(allelopathic index 0.61,high competitive) and Guodao 1(allelopathic index 0.55,high competitive) were used.In the pot experiment PI312777 and Guodao 1 showed strong inhibition but Xiushui 63 had no effects on the germination of barnyardgrass under monoculture.However,the germination rate of barnyardgrass was significantly reduced in the pots mixed planted Xiushui 63 with PI312777 or Guodao 1.Both pot and field experiments showed that the biomass of barnyardgrass was significantly lower in pots or plots of PI312777 and Guodao 1 than in Xiushui 63 under monoculture.Moreover,the biomass of barnyardgrass was significantly decreased in the pots or plots of Xiushui 63 mixed-planting with PI312777 or Guodao 1.The results suggested that mixed-planting of rice varieties could enhance the resistance of Xiushui 63 to barnyardgrass.
    研究简报
    Effects of Protein Content Selection on Cooking and Eating Properties of Rice in Early-Generation of Crosses
    QIAN Chun-rong ,FENG Yan-jiang ,YANG Jing ,LIU Hai-ying ,JIN Zheng-xun
    2007, 21(3): 323-326 . 
    Abstract ( )   PDF (31KB) ( )  
    Two crosses(Xixuan 1 × Tong 769 and Dongnong 423 × Foukei 180) from four japonica rice varieties were made to study the effects of protein content selection on cooking and eating properties of rice in early generations.Coefficients of variation of quality properties varied from 9.73% to 94.99% and negative correlation was noted between protein and amylose contents.The taste meter value firstly increased with protein content decreased and then declined when protein content declined to a critical value.Progenies with moderate protein and amylose contents had higher taste meter value.RVA viscosity properties improved with protein content declined when protein content was much higher,but gradually degraded when protein content declined to some levels.Protein content with too high or too low levels would lead to inferior cooking and eating quality.Therefore,coordinating protein content with amylose content was an important approach for improving rice cooking and eating quality.

    Effect of Chalkiness on Cooking,Eating and Nutritional Quality in Two indica Rice
    LIU Qi-hua ,CAI Jian ,LIU Min ,CHAI Ting-you ,LI Tian
    2007, 21(3): 327-330 . 
    Abstract ( )   PDF (93KB) ( )  
    The effect of chalkiness on eating,cooking and nutritional quality was investigated with Gangyou 527(indica hybrid rice) and Zhaiyeqing 8(conventional indica rice) as materials.Compared with milled rice without chalkiness,amylose content,final viscosity,setback and consistence increased significantly,gel consistency,peak viscosity and breakdown decreased remarkably and other RVA values did not have significant changes in chalky milled rice of Gangyou 527.The difference in the above indices between chalky and non-chalky milled rice in Zhaiyeqing 8 was not remarkable.Crude protein content of chalky milled rice in Zhaiyeqing 8 was significantly lower than that of non-chalky rice,but there was not remarkable changes between chalky and non-chalky milled rice in Gangyou 527.Glutelin content fell significantly,albumin,globulin,prolamine and lysine contents did not change remarkably in chalky milled rice compared with non-chalky milled rice in the two varieties.
    Variations in Grain Phytic Acid and Protein Contents among japonica Rice Cultivars from Jiangsu-Zhejiang Area and Their Correlation
    WU Wei ,CHENG Fang-min ,LIU Zheng-hui
    2007, 21(3): 331-334 . 
    Abstract ( )   PDF (83KB) ( )  
    Twenty-nine japonica rice cultivars from Jiangsu and Zhejiang Provinces,China were used to investigate the variation and frequency distribution in grain phytic acid and protein contents in a field experiment in Hangzhou,and the correlations among grain phytic acid,total protein contents and four protein fractions were analyzed.Grain phytic acid content ranged from 0.699% to 1.034%,with a mean of 0.868%,in which Xiushui series of japonica rice cultivars generally exhibited lower phytic acid level than Wuyujing and Huai series;A roughly normal distribution,with a mean of 8.722%,was observed in total protein content of 29 japonica rice cultivars.Of four protein fractions,glutelin,globulin and albumin had larger coefficient of variation than prolamin,although their difference in prolamin content was cultivar type-dependent;No significant correlation was found between grain phytic acid and protein contents,while total protein content was significantly and positively related to glutelin content.