Number of Pollen Grains in Rice Cultivars with Different Cool-Weather Resistance at the Young Microspore Stage

Abstract

The difference in the number of pollen grains may be the primary factor determining the resistance to cool weather at the young microspore stage in rice (Oryza sativa L.) cultivars. To confirm this hypothesis, we compared the number of pollen grains among the cultivars or lines with various cool-weather resistance. The cultivars or lines used in the experiments were mainly released or grown in the Tohoku district (the northern part of the mainland of Japan). The number of pollen grains showed high correlation with the degree of cool-weather resistance, but considerably varied with the cultivar or line, even in the group having the same cool-weather resistance. Each group with different cool-weather resistance was divided into two subgroups, implying the existence of another genetic factor determining the resistance. The number of pollen grains in the plants cooled at the young microspore stage showed higher correlation with the degree of the cool-weather resistance than that in the control plants without exposure to low temperature. The correlation between the pollen number and spikelet sterility was also analyzed using the data of Satake and Shibata (1992, Jpn. J. Crop Sci. 61 :454–462), who primarily used the cultivars in Hokkaido (the northernmost island of Japan). The results were basically the same as those obtained in the present experiments. These results confirmed the hypothesis that the variation in the number of pollen grains is a primary factor of the resistance to cool weather at the booting stage in the cultivars in the northern part of Japan. The results also suggested the existence of another genetic factor determining the resistance.     

Study on Expression of Bcl-2 and PCNA Genes in Testicular Tissue of Chickens,Quails and Chicken-quail Hybrids

In order to investigate the molecular mechanism of stunted growth testis of chicken (♂) and quail (♀) hybrids. 84 testicular tissue samples of New Roman cocks, male Korean quails and chicken-quail hybrids at different developmental stages were collected,the mRNA expression of Bcl-2 and PCNA genes in testicular tissue of cocks, quails and chicken-quail hybrids at different growth stages were detected using Real-time PCR. The results showed that the Bcl-2 and PCNA genes mRNA expression patterns in testes of chickens and quails at different growth stages were similar.The Bcl-2 gene was fluctuated in a whole, and decreased to the lowest value, then recovered rapidly and remained at a high level. The PCNA gene had a very significant peak value.Compared with the chicken and quail,the expression of Bcl-2 and PCNA genes mRNA in hybrids had no obvious change, which indicated that the pattern of the Bcl-2 gene regulation apoptosis in testis was different from chicken and quail at the hybrid testicular development process, and there was no obvious cell appreciation process.It was suggested that the molecular influencing factors of testicular dysplasia of chicken and quail hybrids were related to the abnormal expression of Bcl-2 and PCNA genes mRNA in testes.The results provided an important reference for the further study of the mechanism of testicular dysplasia between chicken and quail interspecific hybrids.     

四季蜜龙眼花芽形成相关基因SAM的克隆

以四季蜜龙眼花芽为材料,进行了总RNA的提取与纯化,应用RT-PCR技术扩增其3′端序列,经测序和拼接,获得SAM3′末端,共1 253 bp;序列分析表明,与杨树SAM基因同源性达到96%,为龙眼成花机理的深入研究奠定了基础。     

RAPD技术在产气荚膜杆菌基因分型中的应用研究

采用随机扩增多态性ＤＮＡ技术对产气荚膜杆菌进行ＰＣＲ扩增。结果产气荚膜杆菌Ａ，Ｂ，Ｃ，Ｄ４个型均可扩增出约４３０ｂｐ的条带，Ｂ，Ｃ型还扩增出约２１０ｂｐ条带，Ｂ，Ｄ型还扩增出约１２１０ｂｐ条带，Ａ型还扩增出约２４０ｂｐ和６９０ｂｐ条带，各型之间的条带差别明显，从而为产气荚膜杆菌的基因分型、ＰＣＲ快速诊断提供可靠的依据。     

猪肌细胞生成素基因的研究进展

综述猪肌细胞生成素(MyoG)对猪产肉量影响的作用机制和猪肌细胞生成素基因的定位及结构,并分析其PCR-RFLP遗传变异.     

新色型突变棕色貉毛色遗传初探

2006年首次发现新色型突变棕色貉，近3年内累计扩繁89只。依据孟德尔遗传定律，对不同选配组合后代毛色分离数据的统计分析和x^2适合性检验证明，其突变棕色毛色基因为显性，基因型为杂合体。建议其基因符号用“G”表示，基因型为“Gg”。     

基因芯片技术及口蹄疫病毒基因芯片研究进展

口蹄疫的暴发与流行给世界各国的畜牧生产、社会经济和国际贸易构成严重威胁并造成巨大的经济损失，经典的血清学和PCR检测方法越来越不适应进出口动物检疫的快速、准确、高通量的要求。建立一种快速的诊断方法，使其在很短时间能够区别各血清型口蹄疫和其他水泡性疾病是非常必要的。口蹄疫病毒基因芯片包括155个寡核苷酸探针，总长35bp-45bp，设计在VP3-VPl-2A区，既有共有的病毒型别，也包含特异的血清型别。这项技术的优点是能在单一的芯片上检测多元病原体。     

水稻Pi基因分子标记的物理图谱锚定

整理国际注册或期刊报道的已定位Pi基因,并在物理图谱上锚定,为抗稻瘟病基因-Pi基因的精细定位、图位克隆提供研究基础.利用www.gramene.org网站公布的Pi基因的分子标记,在测序图谱Gramene Annotated Nip-ponbare Sequence 2006上进行物理图谱锚定.通过本研究把已定位的89个Pi基因的42个锚定到其物理图谱的28个位点上.这42个Pi基因,除了已克隆的11个基因外,其余的均可作为Pi克隆基因的候选基因作进一步的研究.     

活性氧和一氧化氮在植物——病原体互作反应中的作用

植物被病原体感染后，植物体内活性氧产量急剧增加，这一现象被称为氧爆。活性氧族包括如单线态氧1O2、超氧阴离子自由基O2-.、氢过氧自由基HO2·、过氧化氢H2O2、羟自由基·OH等。与ROS关系密切的一氧化氮，属于活性氮族。ROS和NO参与植物生长发育调控和对环境胁迫的应答反应，特别是在对抗外来病原体的入侵的防卫过程中发挥了重要作用。本文主要讨论ROS和NO在植物与病原体相互作用中发挥的作用。