复硝酚钠对低温下黄瓜种子萌发和幼苗耐寒性的影响

为缓解低温胁迫对黄瓜(Cucumis sativus L.)幼苗的伤害,以黄瓜中农106为试验材料,研究不同浓度复硝酚钠(CSN)浸种对低温胁迫下黄瓜种子萌发及萌发后生长的影响,以及CSN灌根处理对黄瓜幼苗壮苗效果及幼苗耐寒性的影响。结果表明,适宜浓度的CSN浸种能显著提高低温胁迫下黄瓜种子的发芽率、发芽势、发芽指数、活力指数、侧根数和鲜重,以50 mg·L^-1浓度效果最佳。在黄瓜育苗过程中,100 mg·L^-1的CSN灌根处理能显著提高穴盘苗质量和壮苗指数,低温胁迫下CSN通过促进矿质元素吸收,提高幼苗叶绿素含量、净光合速率、根系活力、可溶性蛋白含量和抗氧化酶活性,提高生长素(IAA)和油菜素内酯(BR)含量,降低活性氧和丙二醛(MDA)含量以提高幼苗的耐寒性。本研究为培育黄瓜壮苗和提高黄瓜幼苗耐寒性提供了新方法,也为复硝酚钠在设施蔬菜上的应用提供了技术支持。     

Efficient Yield of Embryoids by Culture of Isolated Microspores of Different Brassicaceae Species

Microspore culture of rapeseed (Brassica napus) is well established in practical plant breeding as a potent method to produce homozygous plants. Except for B. carinata the method has not yet been applied to other Brassicaceae species. The present study describes successful microspore culture of B. campestris, B. nigra, B. oleracea and Raphanus sativus, overcoming the break down of such microspore cultures possibly arising from the release and accumulation of toxic substances into the medium. The modified procedure is as follows: exchange of the incubation medium after one day of culture, addition of activated charcoal to the medium and aerating the three day old microspore culture by agitating the petri dishes on a specially constructed shaker.     

The Gene Pools of the Grasspea (Lathyrus sativus L.)

Interspecific hybridization between the grasspea, Lathyrus sativus, and 15 wild species in Section Lathyrus is reported. Only two species, L. amphicarpos and L. cicera produced viable F¹ hybrids with low fertility when crossed with L. sativus as male parent. Crosses with six other species produced pods following pollination when L. sativus was the male, but seedlings were inviable, seeds did not germinate or pods were empty or had totally shrivelled seeds. When L. sativus was the female parent, only one cross with L. gorgoni produced an F¹, but the seedling was inviable. The germplasm resources of the grasspea are identified, with L. amphicarpos and L. cicera placed in the secondary gene pool and the other species in the tertiary gene pool. The definition of these germplasm resources is discussed in terms of grasspea improvement through plant breeding.     

萝卜中具溶菌酶活性组分的分子结构分析

[目的]分析萝卜具有溶菌酶活性组分CBPs的分子结构,以期为其作用机制和在萝卜中的生理功能提供资料。[方法]利用亲和层析法及CM-纤维素离子交换柱层析分离纯化CBPs,测定其氨基酸组成、糖基和溶菌酶活性中心残基。[结果]从萝卜中得到了2个具溶菌酶活性且无糖基的组分:CBP1和CBP2,它们间氨基酸组成差异不大;Asp/Glu和His专一性化学修饰剂单独作用后,CBP1和CBP2相对溶菌酶活力均大幅度降低,预先加入竞争性抑制剂则下降的幅度减小。[结论]萝卜中有2个具溶菌酶活性的非糖蛋白组分,其溶菌酶活性中心氨基酸残基均可能含有Asp/Glu和His。     

黄瓜根结发育早期WRKY基因的分离

为了确定黄瓜根结线虫侵染早期与取食位点形成相关的WRKY基因,以根结线虫侵染早期的黄瓜根为材料,基于黄瓜全基因组WRKY基因预测,进行RT-PCR扩增.在根结线虫侵染早期的黄瓜根组织中共分离到24个WRKY基因,分别定位于黄瓜的7条染色体上.系统进化分析表明,在分离到的WRKY基因中有17个为第二家族,6个为第一家族,1个属于第三家族.初步确定8个WRKY基因为根结线虫诱导表达基因,推测黄瓜根结线虫侵染早期为涉及多个WRKY基因参与的复杂调控体系,为进一步研究黄瓜根结线虫取食位点发育机制奠定了基础.     

Structure of the Cochliobolus sativus population variability

The genetic diversity of several local populations of the fungal pathogen Cochliobolus sativus, collected over 3 years from different regions of the Czech Republic, was examined using amplified fragment length polymorphism (AFLP). A high level of variability was found even among isolates from one lesion. Measures of multilocus linkage disequilibrium suggested that recombination has a minor impact on the genetic structure of populations. Cochliobolus sativus forms genetically divergent populations (F_ST = 0·33), indicating a low level of geneflow between populations. This was supported by a significant correlation between genetic diversity and geographical distances up to 80–100 km. The most likely explanation for the genetic variability is that the fungus forms conidia with highly variable chromosomal rearrangements. The differentiation observed among local populations implies that genetic drift, including a founder effect, combined with restricted migration generates the structure of C. sativus populations.     

黄瓜L-半乳糖-1,4-内酯脱氢酶cDNA全长的克隆和遗传转化

以黄瓜D08108果实为材料,根据GenBank中登录的甜瓜L-半乳糖-1,4-内酯脱氢酶(GalLDH)的序列设计引物,采用RT-PCR方法扩增出黄瓜GalLDH的cDNA全长,GenBank登录号为 HQ446099.黄瓜GalLDH的cDNA序列全长1880 bp,包含一个长为1773 bp的完整开放阅读框,编码590个氨基酸.其核苷酸序列与已知其他植物核苷酸序列间的同源性达70%以上.共检测得到5棵转基因植株     

黄瓜靶斑病菌接种体的繁殖

黄瓜靶斑病是近年来严重为害保护地黄瓜生产的一种新病害,为了促进靶斑病的抗病育种和防治,开展了12种固体和液体培养基配方、病菌移植方式、菌落颜色、光照条件、培养时间对黄瓜靶斑病菌繁殖效果的研究。结果表明,靶斑病菌菌落颜色深的菌株孢子产量大于菌落颜色浅的菌株;采用菌块涂抹法移植靶斑病菌效果最佳;繁殖靶斑病菌适宜的培养基为CZA120g,CZA80g,液体培养不适合靶斑病菌的繁殖;连续光照和黑暗处理对菌丝生长无显著影响,暗培养比光、暗交替和连续光照更有利于孢子的产生;28℃恒温、黑暗培养5 d是靶斑病菌产孢高峰期,分生孢子数量可达20.7×105个/mL。     

西红花组织培养研究进展

为了研究人工繁育西红花种球的途径,笔者综述了国内外30多年以来的西红花组织培养研究进展,发现利用不同的外植体都有诱导形成小球茎或完整植株的报道,但是其诱导周期长、诱导率较低,未见进行大规模产业化生产的报道。因此,今后应该着重于研究如何缩短诱导周期,提高诱导率、增殖率,加快大球茎培育进程,并进行花器官和子房的组织培养研究,提高柱头状物诱导率,加强细胞大规模培养技术研究,推动次生代谢产物生产的规模开发。笔者就西红花组织培养的研究成果进行了归纳与综述,并对西红花组培进展进行了展望,以期为中国西红花种球规模化和产业化生产提供参考。