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82.
A restricted maximum likelihood analysis applied to an animal model showed no significant differences (P > 0.05) in pH value of the longissimus dorsi measured at 24 h post-mortem (pH24) between high and low lines of Large White pigs selected over 4 years for post-weaning growth rate on restricted feeding. Genetic and phenotypic correlations between pH24 and production and carcass traits were estimated using all performance testing records combined with the pH24 measurements (5.05–7.02) on slaughtered animals. The estimate of heritability for pH24 was moderate (0.29 ± 0.18). Genetic correlations between pH24 and production or carcass composition traits, except for ultrasonic backfat (UBF), were not significantly different from zero. UBF had a moderate, positive genetic correlation with pH24 (0.24 ± 0.33). These estimates of genetic correlations affirmed that selection for increased growth rate on restricted feeding is likely to result in limited changes in pH24 and pork quality since the selection does not put a high emphasis on reduced fatness. 相似文献
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在室内外调查研究的基础上,应用生物多样性基本原理,首次论述了库尔勒市区草坪植物区系、染色体遗传、生活型、生态型、植物景观和资源植物的多样性及其质量特征。结果表明,库尔勒市区草坪植物的多样性,在植物物种组成上,以人工栽培和引种为主,本土杂草为辅;在地理成分上,以本土地理成分为主,外引地理成分为辅;在染色体组型上,以单染色体组型为主,多染色体组型为辅;在生活型组成上,以木本植物为主,草本为辅;生态类型组成上,以中生为主,旱生为重要组成部分,湿、水生为补充;在植物景观组成上,以2、4、5要素景观为主,1、3要素景观为辅;在资源植物构成上,以环境和生产类为主,食用和特殊类为辅。 相似文献
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对36份具有代表性的西南地区野生狗牙根材料采用同工酶进行遗传多样性研究,筛选出优良草坪草C1,C32,C9和部分优良育种材料,为西南地区狗牙根的开发利用及申报品种提供理论依据。 相似文献
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选用草原红牛及其与利木赞牛的杂交后代66头作为试验牛群体,提取血液及肝脏基因组DNA,设计8对微卫星引物进行PCR扩增,从分子水平上对草原红牛及其杂交群体8个位点的遗传多态性进行微卫星分析。结果表明,在草原红牛中,ETH225、IDVGA2、IDVGA46和IDVGA44等位基因数分别为5、4、3和4,多态信息含量(PIC)分别为0.5420、0.6736、0.5218和0.5750,这4个位点均为高度多态。而另4个位点BM2113、BM1824、IDVGA55和TGLA44等位基因数分别,2、2、2和5,多态信息含量分别为0.3698、0.3604、0.3538和0.4708,属于中度多态性位点。在杂交牛群体中,BM2113、ETH225、IDVGA2、IDVGA46、ID- VGA44、BM1824、IDVGA55和TGLA44这8个位点的等位基因数分别为4、5、4、4、5、4、4和6,多态信息含量(PIC)分别为0.6432、0.5943、0.6593、0.5794、0.7259、0.6121、0.6120和0.6204,杂合度为0.7034,均属于高度多态性位点。这些微卫星位点作为遗传标记应用于草原红牛遗传育种研究之中是可行的。 相似文献
89.
Yasuhiro Inoue Takayuki Matsuura Tatsuji Ohara Koji Azegami 《Journal of General Plant Pathology》2006,72(2):111-118
The entire genome of bacteriophage OP1, lytic for Xanthomonas oryzae pv. oryzae causing bacterial leaf blight of rice, and the partial genomes of related phages were sequenced and analyzed. The OP1 genome comprises double-stranded, 4785-bp long DNA with 51.1% G + C content. Fifty-nine open reading frames (ORFs) were detected.
ORF25 had similarity with the tail fiber gene of phages, whose product is related to host specificity. The ORF25 regions were
amplified from four host-range mutants (OP1h, OP1hC, OP1h2, and OP1h2C) by polymerase chain reaction, and their deduced amino acid sequences were compared. Three mutants (OP1hC, OP1h2, OP1h2C) had duplications of a small domain in the N-terminal portion, although there were slight differences in the position of the duplicated sequences. One mutant OP1h had substituted amino acids in the duplication region. New mutants isolated in the laboratory (OP1hC and OP1h2C from OP1 and OP1h2) acquired the ability to lyse strain N5874 belonging to phagovar (lysotype) C. However, they rapidly lost this lytic ability
when incubated with other phagovars. This loss was always accompanied by a loss of the characteristic repeats, suggesting
that the host range of OP1-related phages changed mainly through duplication and deletion of a small domain in ORF25.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession numbers AP008979,
AB214312 to AB214316 相似文献
90.