三分体形成是大白菜2n雄配子发生的主要途径

用能自然产生２ｎ配子的二倍体大白菜ＢＰ０５８为材料,研究了２ｎ雄配子发生的细胞学机制。结果表明,大白菜２ｎ雄配子的形成主要是由于减数分裂过程中,中期Ⅱ两个纺锤体的定向发生改变所致,即由正常的相互垂直定向改变为八字形和平行形定向。     

Cloning and Characterization of the Microspore Development-Related Gene BcMF2 in Chinese Cabbage Pak-Choi （Brassica campestris L. ssp. chinensis Makino）

For the sake of providing some important information relevant to the study of the molecular mechanism of genic male sterility in plants, gene differential expression in flower buds at different developmental stages, as well as in rosette leaves, florescence leaves, and scapes was analyzed using cDNA amplified fragment length polymorphism (cDNA-AFLP) in the genic male sterile A and fertile B line of Chinese cabbage pak-choi. Following amplification of 125 pairs of primer combinations, 11 differential fragments were obtained, of which eight were from the B line and the other three were from the A line. Of 11 differential fragments, four were verified by Northern hybridization that were expressed preferentially in fertile flower buds. Results of GenBank BLAST showed that one fragment was with unknown function, whereas the other fragments have strong nucleotide sequence similarities with the polygalacturonase (PG) gene, the pectinesterase (PE) gene, and the polygalacturonase inhibitory protein (PGIP4) gene. Only fulllength cDNA from the differential fragment BcMF-A 18T 16-1 was amplified by rapid amplification of cDNA ends (RACE) and Northern analysis showed that this fragment was expressed only in medium and largesized flower buds of the B line. The full-length cDNA, designated as BcMF2 (Brassica campestris Male Fertile 2), was 1 485 bp long and was composed ofa 1 263-bp open reading frame, which had 83% nucleotide similarity to a PG gene from Arabidopsis encoding polygalacturonase. Analysis of the basic structure of the protein revealed that it had one polygalacturonase active site (RVTCGPGHGLSVGS) at 256th site of amino acids and was classified as being a member of family 28 of the glycosyl hydrolases. The role of the BcMF2gene on microspore development is discussed in the present paper.     

大白菜线粒体DNA有效、快速提取方法

目的:建立一种有效、快捷的大白菜线粒体DNA(mtDNA)提取方法。方法:采用差速离心和蔗糖衬垫相结合的方法先从大白菜胞质雄性不育系及保持系叶片中分离出线粒体,然后用SDS—蛋白酶K裂解法提取mtDNA。结果:琼脂糖凝胶电泳表明,采用该方法提取的mtDNA片段大小在30~45kb之间,电泳条带清晰,无明显降解发生;以提取的mtDNA为模板进行RAPD反应,不育系和保持系均扩增出较多的条带,而且呈现出丰富的多态性,大小分布在500bp-3000bp之间,且条带清晰,没有脱尾现象。结论:该方法提取mtDNA,省时、省钱,对实验设备要求较低,而且分离出的mtDNA质量较高,能满足后续分子生物学研究工作需要。     

大白菜雄性不育系的组织培养和快速繁殖技术研究

以大白菜雄性不育系Bm5-3为材料,研究其组培快繁技术的结果表明:腋芽以组培快繁技术保存、扩繁大白菜雄性不育系是可行的。适合其腋芽增殖的培养基是MS+2mg·L-16-BA+0.1mg·L-1NAA,增殖系数为4.58,一般通过4￣5次继代即可脱分化;适合其生根的培养基是B5+0.1mg·L-1IBA,平均每株生根数为8.5条,平均根长8.18cm,这一培养基上生长的根较粗壮。具有4~5片叶子且根系发达的试管苗,移栽成活率高达95%。田间栽培的试管苗与供体植株的外部形态与生理特性完全一致。     

大白菜生物技术研究进展

综述了国内外在大白菜(Brassica rapa ssp.pekinensis)单倍体培养、基因工程和分子标记方面的最新研究成果.重点讨论了大白菜小孢子培养的影响因素、取材要点、培养条件、植株再生和倍性鉴定以及大白菜的转基因载体选择、受体系统建立、遗传转化与转基因植株鉴定等.对小孢子培养及转基因研究的原理、方法和关键技术进行了总结.展望了大白菜生物技术研究的应用前景.     

大白菜相对于结球甘蓝连锁群特异SSR标记的筛选

以9个大白菜品种和10个结球甘蓝品种为试材,对位于芸薹属A基因组10个连锁群的207对SSR引物进行PCR筛选,共筛选出33个大白菜相对于结球甘蓝的特异SSR标记,涉及了大白菜的10个连锁群,其中位于A1连锁群3对,A2连锁群4对,A3连锁群5对,A4连锁群2对,A5连锁群3对,A6连锁群4对,A7连锁群2对,A8连锁群1对,A9连锁群2对,A10连锁群7对。为进一步利用SSR标记鉴定结球甘蓝—大白菜异附加系奠定了基础。     

大白菜BrMYB34-3基因的3′-RACE克隆及表达

以大白菜叶片为材料,根据NCBI数据库中Br MYB34-3基因序列的已知信息,利用3-RACE获得了Br MYB34-3基因全长,用RT-PCR方法对Br MYB34-3在不同组织中的表达进行分析.结果显示,该基因全长1 135 bp,编码280个氨基酸.Br MYB34-3具有R2R3-MYB(含有2个MYB结构域的转录因子)典型的R2、R3结构域及基序.其氨基酸序列与大白菜的Br MYB34-1和Br MYB34-2、拟南芥的At MYB34具有较高的一致性.Br MYB34-3在莲座叶、当天开的花中表达水平较高,在花序顶端表达水平较低,在根和花序轴中未检测到表达,这与拟南芥At MYB34的表达模式不同.研究表明,Br MYB34-3是大白菜中的MYB34同源基因,在功能上可能与拟南芥At MYB34基因存在差异.     

腐植酸水溶肥料在白菜上的肥效试验

腐植酸水溶肥料是一种新型肥料,在农业生产中得到广泛应用。本实验以白菜为实验作物,在常规施肥减量40%的基础上浇施腐植酸水溶肥肥料三次,对白菜产量进行统计分析,研究验证腐植酸水溶肥料是否对作物的生长起到促进的作用。研究报告表明,白菜施腐植酸水溶肥料,经济性状改善,增产增效,增产率高达40.4%,亩增加收益明显,与各处理相比均达极显著水平,肥效显著。     

Impact of habitat diversification on arthropod communities： A study in the fields of Chinese cabbage, Brassica chinensis

Field trials were carried out from June to August in 2004 at Wuyishan （Wuyi Mountains）, Fujian province, China, to determine the effects of habitat diversification on arthropod communities. Two Chinese cabbage, Brassica chinensis, field 1 （F1） and field 2 （F2） surrounded by diverse vegetable cultivars were selected, while a monoculture of Chinese cabbage served as the control field （CK）. The results showed that： （i） when comparing insect abundance of each order between different habitats, significantly higher numbers of lepidopterous insects （39.76% from the each order） and lower densities of Hymenoptera （19.82%） were found in CK than in F1 and F2; （ii） compared with CK, F1 and F2 had a lower percentage of species richness and an abundance of herbivorous insects, but increased richness, abundance and biodiversity of predatory insects; （iii） no differences were observed in neutral insects＇ guild between different fields; and （iv） the dominant species for each guild depends on the habitat types and sampling dates. This study suggests that intercropping could conceivably be used in these habitats to increase the population of natural predators, thus achieving desirable and ecologically friendly results in vegetable fields.     

大白菜—结球甘蓝1号二体异附加系分子标记鉴定及其自交后代的性状分析

利用与抗霜霉病、抗芜菁花叶病毒基因连锁的SCAR标记和能够区分大白菜和结球甘蓝FLCs基因的特异引物对大白菜—结球甘蓝1号二体异附加系(AC1d)及其亲本进行分析,结果表明:AC1d及其双亲中均含有与抗霜霉病基因连锁的标记;AC1d和亲本结球甘蓝中含有与抗芜菁花叶病毒基因连锁的标记,亲本大白菜中无该标记;AC1d除具有4个大白菜Br FLCs基因外,同时还添加了结球甘蓝Bo FLC3基因。AC1d自交后代的株高、株展、球高、维生素C含量、可溶性蛋白质及其7种硫苷组分含量超出了亲本大白菜和结球甘蓝;叶形指数、可溶性糖含量和对小菜蛾的抗性等超出了亲本大白菜。为利用AC1d后代选育携有目标性状的易位系提供了依据。