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171.
详细介绍了东京大田农产品批发市场和名古屋批发市场在果菜、水产、花卉方面的交易情况,并对日本批发市场的设置程序和交易原则进行了简要阐述,最后提出发展中国批发市场的几点建议。  相似文献   
172.
We previously surveyed chromosomal regions showing segregation distortion of RFLP markers in the F2 population from the cross between a japonica type variety ‘Nipponbare’ and an indica type variety ‘Milyang23’, and showed that the most skewed segregation appeared on the short arm of chromosome 3. By comparison with the marker loci where distortion factors were previously identified, this region was assumed to be a gametophytic selection-2 (ga2) gene region. To evaluate this region, two near isogenic lines (NILs) were developed. One NIL had the ‘Nipponbare’ segment of this region on the genetic background of ‘Milyang23’ (NIL9-23), and the other NIL had the ‘Milyang23’ segment on the genetic background of ‘Nipponbare’ (NIL33-18). NIL9-23 and ‘Milyang23’, NIL33-18 and ‘Nipponbare’, and ‘Nipponbare’ and ‘Milyang23’ were respectively crossed to produce F1 and F2 populations. The F1 plants of NIL9-23 × ‘Milyang23’ and NIL33-18 × ‘Nipponbare’ showed high seed fertility and the same pollen fertility as their parental cultivars, indicating that ga2 does not reduce seed and pollen fertility. Segregation ratio of a molecular marker on the ga2 region in the three F2 populations was investigated to clarify whether segregation distortion occurred on the different genetic backgrounds. Segregation distortion of the ga2 region appeared in the both F2 populations from the NIL9-23 and ‘Milyang23’ cross (background was ‘Milyang23’ homozygote) and the ‘Nipponbare’ and ‘Milyang23’ cross (background was heterozygote), but did notin the F2 population from the NIL33-18 and ‘Nipponbare’ cross (background was ‘Nipponbare’ homozygote). This result indicates that ga2 interacts with a ‘Milyang23’ allele(s) on the different chromosomal region(s) to cause skewed segregation of the ga2 region. In addition, segregation ratio was the same between the F2 populations from NIL9-23 × ‘Milyang23’ and ‘Nipponbare’ × ‘Milyang23’ crosses, suggesting that the both genotypes, ‘Milyang23’ homozygote and heterozygote, of gene(s) located on the different chromosomal region(s) have the same effect on the segregation distortion. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
173.
中国乳制品工业的10年回顾与展望   总被引:2,自引:0,他引:2  
回顾了中国乳制品工业的发展历程以及10年来所取得的成就.在分析乳制品市场供需关系变化、人们膳食结构变化、乳品消费现状和消费区域转化的基础上,论述了未来5年中国乳品业的发展前景,指出乳制品行业的企业家和员工要审时度势,与时俱进,齐心协力地推动乳制品行业持续、健康地向前发展.  相似文献   
174.
Based on the theory of value chain,this paper explained the constitution of the value chain and the important function of channels in Real Estate sale promotion.Furthermore,it analyzed the erroneous ideas about the present management of the channels for sale promotion systematically.And for the lower-cost and high-efficiency purpose,it puts forward the viewpoint that channels should be established and integrated based upon the value chain theory,moreover,the key point in the process was discussed.  相似文献   
175.
S. Y. Lin  H. Ikehashi 《Euphytica》1993,67(1-2):35-40
Summary A locus for male gamete abortion in hybrids for Japonica and Indica rice was identified with the aid of marker genes Rc and Est-9 on chromosome 7. In an Indica-Japonica cross, AKAMAI 1/IR50, the Indica allele Est-9 2 was transmitted via the male gamete with a ratio of 0.29 instead of the normal 0.5, whereas no segregation distortion was observed for the Rc locus. The recombination value (p) for Est-9 and Rc was estimated to be 0.38 by a least square method after adjusting Mendelian segregation ratios with the male transmission ratios of 0.29 (Tr) for Est-9 2 and 0.71 (1-Tr) for Est-9 1. The recombination value (q) for the new locus for male gamete abortion, ga-11, and Est-9 was estimated to be 0.23 by using 56 F3 lines from F2 plants which were heterozygous for the Est-9 locus. No linkage for Rc and ga-11 was found. Therefore, the two markers and ga-11 were located in the order of ga-11-Est-9-Rc. Using the estimated recombination value (q), the male transmission rate (k) of ga-11 a was estimated to be 0.11 with the F2 data and-0.07 with the F3 line data. Thus, it was apparent that male gametes possessing ga-11 a were frequently aborted in the Indica-Japonica hybrid.  相似文献   
176.
A total of 147 simple sequence repeat (SSR) markers (including86 barley and 61 wheat microsatellite markers) were tested for their segregation in a doubled haploid (DH) and an F2 population of barley. The DH population consisted of 71 doubled haploid lines, developed from F1 plants of a cross between Tadmor and WI2291using isolated microspore culture technique. A genetic linkage map consisting of 43 microsatellite markers was constructed using the DH population. Particularly on chromosome 4H microsatellite markers showed distorted segregation ratios. Segregation of DH lines based on molecular markers were compared with segregation of 92 F2 lines from the same cross. The proportion of loci deviating from the expected monogenic segregation ratios in the DH population was significantly higher (19/43loci, 44%) than in the F2 population (7/43 loci, 16%). The deviation was biased towards the WI2291 parent alleles. In line with this observation, WI2291 was found to perform better than Tadmor in regenerating green plantlets with the isolated microspore-culture technique. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
177.
在对农产品加工业现状分析的基础上预测了我国农产品加工业市场特征的发展趋势,并为我国农产品加工企业做大做强提出了对策意见。  相似文献   
178.
在对籼稻缙恢10进行EMS(ethyl methane sulfonate)处理后的群体中,发现一个花器官突变体,主要表现为内稃扭曲并呈现外稃化特征,浆片数目增加且呈现稃状特征,雄蕊数目减少至1~4个,部分雄蕊的花丝呈现浆片化特征,暂将其命名为水稻颖壳扭曲突变体palea distortion 1(pd1)。遗传分析表明该突变性状受一个隐形单基因控制。利用群体分离分析法(bulked segregation analysis,BSA),将PD1基因定位在第2染色体的RM13693和RM13936之间,遗传距离分别为3.25cM和3.90cM。该研究结果为PD1基因的图位克隆奠定了基础。  相似文献   
179.
Motion estimation is the most complex part in H.264. Intra prediction is an important part of motion estimation. There are a number of intra prediction modes in H.264, which no doubt greatly increase encoding complexity. In intra prediction, the way of choosing prediction method is rate distortion optimization or using correlation properties. For complexity problem, the paper provides an improved intra prediction mode selection algorithm. This algorithm uses a new detection method to detect the pixel correlation in the direction of mode selection. Test results show that the algorithm has reduced the computational complexity and increased the encoding speed highly in the premise of ensuring video quality.  相似文献   
180.
本文从企业档案在社会主义市场经济中所发挥的重要作用入手 ,层层揭示了企业档案管理过程中所出现的一些问题 ,同时也提出了自己的一些见解 ,以适应企业走向市场的需要 ,为企业档案管理体制的改革指明了方向。  相似文献   
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