不同基因型玉米愈伤组织诱导与植株再生研究

以5个玉米品系幼胚为外植体,研究了基因型、2,4-D浓度以及胚龄对愈伤组织诱导的影响;6-BA对愈伤组织分化的影响;以及IBA对再生芽生根的影响。结果表明：除。31外,其他基因型的外植体在相同条件下均可诱导出愈伤组织,但是不同基因型间存在显著差异;2,4-D浓度和胚龄显著影响愈伤组织的诱导,且2,4-D浓度为2．0mg／L,胚龄在11—13d之间时,玉米愈伤组织诱导率较高且质量较好。将愈伤组织转入分化培养基后,6-BA促进了愈伤组织的再分化;在生根培养基中,IBA促进了再生芽生根,经过炼苗后移栽获得再生植株。     

不同植物生长调节物质对细叶小羽藓愈伤组织诱导及分化的影晌

以细叶小羽藓[Haplocladium microphyllum（Hedw．）Broth．】的配子体为外植体,研究了不同植物生长调节物质对细叶小羽藓愈伤组织诱导及分化的影响。结果表明：在Ms培养基中添加不同的植物生长调节物质对细叶小羽藓配子体增殖影响差异很大,具体表现为2,4一D、KT、IBA和IAA促进细叶小羽藓芽体的诱导及生长,NAA抑制细叶小羽藓芽体的诱导,TDZ阿姨、、及6－BA促进细叶小羽藓的配子体产生愈伤组织;在Ms培养基中添加0．3mg·L－1。6-BA最适合愈伤组织的诱导;在MS掊养基中添加1．0mg·L－1。。IBA最适合愈伤组织的分化。     

何首乌愈伤组织的诱导

研究了外植体、光暗条件、植物激素等因子对何首乌愈伤组织诱导的影响 ,以及 6 -BA和何首乌组织提取液对愈伤组织增殖的影响。结果表明 :茎段的愈伤组织诱导优于带侧芽茎段和叶片 ;光照有利于愈伤组织的诱导 ;4因子 4水平的正交实验表明 ,对何首乌茎段愈伤组织诱导的影响 2 ,4 -D >6 -BA >IBA >IAA ,最佳激素搭配是 :MS +2 ,4 -D 2mg L +6 -BA 1mg L +IBA1mg L或MS +2 ,4 -D 2mg L +6 -BA 2mg L +IAA 1mg L ;MS培养基中附加 6 -BA或组织提取液均促进愈伤组织的增殖。     

冬凌草离体培养体系的建立及主要次生代谢产物的测定

以冬凌草叶片为外植体,研究不同浓度激素组合对冬凌草愈伤组织诱导及植株再生的影响,并对不同外植体(茎、叶)诱导愈伤、芽的分化能力及再生植株内主要次生代谢产物的含量进行了比较研究。结果表明:在MS 2.0 mg/L 6-BA 1.0 mg/L NAA培养基上诱导愈伤组织效果较好;在MS 2.0 mg/L 6-BA的培养基上诱导芽的效果较好;叶片和茎段在愈伤诱导培养基上均能产生大量的愈伤组织,但其再分化能力以茎段最好;再生苗生根培养基以0.3 mg/L IBA最好;以叶为外植体诱导的再生植株中冬凌草甲素、迷迭香酸的含量均高于以茎为外植体诱导的再生植株。     

早熟棉体细胞胚胎发生和植株再生体系的建立

以8个早熟或特早熟棉花为材料,通过不同激素组合(1.0 mg/L IBA+0.5 mg/L KT;0.1 mg/L 2,4-D+0.1 mg/L KT)诱导其愈伤组织,为早熟棉花的遗传转化以及基因功能研究奠定基础.结果表明,2种激素组合均能诱导产生4种主要类型的愈伤组织:淡黄色颗粒状愈伤组织,褐化的愈伤组织,翠绿致密的愈伤组织,疯长型愈伤组织.4种愈伤组织转入增殖培养基中前2种愈伤组织能够分化出胚性愈伤组织,胚性愈伤组织再转到分化培养基上培养能够产生胚状体,即体细胞胚;体细胞胚进一步发育成为再生小苗.用该组织培养再生系统,成功地使晋棉5号、中棉27号和辽棉10号等3个早熟棉品种在5～7个月内通过体细胞胚胎分化获得再生小苗.     

贯叶金丝桃组织培养的研究

分别以甘肃天水贯叶金丝桃的幼根、幼茎、幼叶为外植体．在1／2MS培养基上附加各类激素,进行贯叶金丝桃的组培实验。研究发现各外植体的增殖速率由高到低分别为幼茎、幼根、幼叶,且得到贯叶金丝桃组培各阶段的最佳培养基成分。诱导愈伤组织的培养基为1／2MS 1．3～1．6mg／L BA 0．2mg／L NAA;培养基1／2MS 1．3～1．6mg／L BA 0．15mg／L NAA有利于不定芽的形成;诱导不定根的培养基为l／2MS IBA0．5～O．8mg／L 蔗糖2．0％。向1／2MS培养基中添加不同的生长素(IAA,IBA,NAA,2．4-D)．在不同浓度梯度的培养基上进行诱导贯叶金丝桃的愈伤组织及不定根的试验,结果表明：生长素IAA,IBA既可诱导愈伤组织,又可以诱导不定根的产生。生长素NAA,2,4-D可诱导产生愈伤组织,但对不定根的诱导作用较差。     

栀子组织和细胞培养生产天然食用色素的研究——Ⅰ.愈伤组织培养的研究

在诱导出愈伤组织的基础上,对各种不同的培养条件进行分析研究,考察它们对愈伤组织生长和栀子黄色素产生的影响,筛选出适宜的生长培养基:B_5+IBA 1mg/l+KT0.23mg/l、MG-5+IBA 1mg/l+KT 0.23mg/l、B_6+IAA 1.5mg/l和生产培养基:M-9+IAA 1mg/l、M-9+IAA 1.5mg/l.并且,获得了几个色素含量较高的愈伤组织系。另外,还研究了含色素和不含色素的愈伤组织在培养过程中的过氧化物同工酶的差异。     

杜仲叶片愈伤组织诱导的激素优化研究

以杜仲优树L33的幼叶为材料,在B5培养基上添加不同浓度的生长素与细胞分裂素进行愈伤组织诱导研究,结果表明：无激素的培养基上不能诱导出愈伤组织,单独加入2,4-D、NAA和IBA均可诱导出愈伤组织,以0.5 mg·L^-1 2,4-D、0.5～1.0 mg·L^-1 NAA、1.0 mg·L^-1 IBA出愈率最高,达100%,且愈伤组织生长较好;在适宜浓度的生长素的培养基上加入细胞分裂素时,KT的加入对愈伤组织的诱导及生长起抑制作用;1.0 mg·L^-1 NAA+0.3～0.5 mg·L^-1 BA与1.0 mg·L^-1 IBA+0.3～0.5 mg·L^-1 BA 的组合可明显促进愈伤组织的诱导和生长,适合进一步继代培养。     

玉米芽尖培养中的高频率体细胞胚胎发生与植株再生(简报)

通过诱导玉米芽尖产生胚性愈伤组织,建立起高频率植株再生的玉米芽尖培养实验体系。在MS+1.0mg·L-16-BA+0.2mg·L-12,4-D+500mg·L-1CH的培养基上诱导愈伤组织并继代培养1次后,将愈伤组织转移到Ms+0.5mg·L-16-BA+0.4mg·L-1IBA+500mg·L-1CH的分化培养基上,可形成大量的体细胞胚胎。组织学观察表明,体细胞胚胎主要发生在胚性愈伤组织表面与表层下部。不同基因型的芽尖形成愈伤组织和再生植株的能力不同。     

山茱英的组织培养与植株再生

目的：建立山茱萸的组织培养及植株再生体系。方法：分别以山茱萸的叶片、花柄和花托为材料,进行山茱萸不同外植体的离体培养研究,筛选最佳培养基组成。结果：适宜山茱萸叶片愈伤组织诱导的培养基组合为1／2MS,附加BA2．0mg/L、IBA0,5—1．0mg／L;适宜山茱萸花柄、花托愈伤组织诱导的培养基组合为1／2MS,附加BA1．0mg／L、2,4-D0．5mg／L;在1／2MS附加BA2．0mg／L、IBA0．05mg／L的培养基上,可诱导不定芽的产生;1／2MS附加IBA2．0mg／L的培养基有利于山茱萸试管苗生根。讨论：山茱萸的花托是进行组织培养的最适外植体,白色或翠绿色、结构致密的愈伤组织较易分化产生不定芽。     

冷激对高温胁迫下番茄幼苗生长及花芽分化的影响

为了解苗期冷激锻炼对番茄幼苗生长和花芽分化的影响,试验采用人工气候箱模拟夏季设施高温环境,每天对番茄幼苗进行10 ℃、10 min的冷激锻炼,研究冷激处理对高温胁迫下番茄幼苗生长、叶片超微结构和花芽分化进程的影响,并观察定植后开花和坐果情况.结果表明：在4叶期经过冷激锻炼的番茄幼苗茎粗、壮苗指数分别比对照提高了7.2%和55.5%;经过冷激锻炼处理的番茄幼苗叶片中叶绿体和线粒体等细胞器形状及结构正常完整,一定程度上缓解了高温对番茄幼苗叶肉细胞超微结构的破坏;冷激锻炼显著提高了番茄幼苗早期花芽分化的分化进程,但随着苗龄的延长这种差异变得不显著.定植后经冷激处理的番茄幼苗第1、2穗果的坐果数和坐果率显著高于未经冷激处理.表明冷激锻炼不仅能够缓解高温对番茄幼苗细胞超微结构的伤害和生长的胁迫,还有利于早期花芽分化进程的提前,提高番茄坐果数和坐果率.     

毛酸浆(Physalis pubescens)花形态特征与小孢子发育

许多重要蔬菜和水果隶属于茄科(Solanaceae),植物花发育是物种延续和产品形成关键决定因子。茄科毛酸浆(Physalispubescens)是药食同源半野生浆果,目前其花发育研究不多。为了从不同视角了解茄科植物花发育,本研究采用比较生物学方法从花的形态特征和解剖学层面解析了毛酸浆(P.pubescens)和茄科模式植物番茄(Solanum lycopersicum var. cerasiforme)花器特征和小孢子发育进程。结果显示,开花后毛酸浆花萼迅速生长包被果实、花瓣有紫色斑纹、花药顶颈可育及背部开裂散粉特征与番茄花萼生长缓慢、黄色花瓣、花药顶颈不育及腹缝开裂散粉方式截然不同,展示了茄科植物遗传多样性。毛酸浆小孢子发育,在“四分体”之前迟于番茄,而“四分体”之后期却快于番茄。特别是番茄药隔组织在“四分体”时期开始向药室异常内突,并在花粉成熟期占据药室近1/2空间,而未在毛酸浆中观察到。该研究为开发茄科新的模式植物和从不同视角理解庞大茄科植物花发育提供了重要信息。     

Expression of two gibberellin-regulated cDNAs during early flower development in tomato (Solanum lycopersicon). Effect of grafting and paclobutrazol

To study the role of translocation of gibberellin (GA) intermediates or bioactive GAs from other plant parts to buds during early flower development in tomato ( Solanum lycopersicon ), the effect of grafting and paclobutrazol (PAC) treatment on the expression of tgas100 and tgas118 , two GA-regulated mRNAs, was analysed. Both mRNAs accumulated in a dose-dependent fashion. Application of 0.5 ng GA₃ per bud to developmentally arrested flower buds of a GA-deficient mutant of tomato ( gib-1 ) induced tgas100 expression, while the tgas118 abundance increased. For obtaining normal flower development through anthesis in the mutant, a single GA₃ treatment was required of at least 5 ng GA₃ per bud. In wild-type flower buds, PAC decreased the abundance of tgas100 and tgas118 mRNAs either when PAC was sprayed on whole plants or directly applied to buds. When only the wild-type buds were treated with PAC, the expression profiles characteristic for untreated buds were not restored by translocation of endogenous GAs. Grafting of gib-1 scions onto wild-type donor plants did not result in normal flower development or expression profiles like in wild-type buds. We conclude that the role of GA transport in early flower development of tomato is negligible and that the GAs required for development have to be synthesized in the flower bud itself.     

大棚番茄生长发育与棉铃虫危害的模拟模型研究

根据１９９３～１９９４年大田资料建立了塑料大棚番茄的生长发育动态模型和棉铃虫Ｈｅｌｉｃｏｖｅｒｐａａｒｍｉｇｅｒｚａ（Ｈｕｂｎｅｒ）取食为害模型,动态模拟了番茄的净光合产量和各器官的干物质消长,以及植株的形态建成和产量形成过程,模型把番茄繁殖器官的脱落按其成因归纳为生理的,环境的及病虫害引起的脱落,容量包棉铃虫取食为害模型偶联,棉铃虫对番茄的取食为害模型为第一代,第二代棉铃虫取食不同时期番茄各发育     

Agrobacterium-mediated transformation of tomato elicits unexpected flower phenotypes with similar gene expression profiles

Background

Genetic transformation mediated by Agrobacterium tumefaciens is known to cause unexpected phenotypes. Mutations of a specific set of homeotic genes can result in alterred floral structure.

Methodology/Principal Findings

Previously we identified two genes (LeTGA1 and SOLly GLB1) induced by nutrient availability in tomato. To further elucidate their function, we sought to knock out the genes using antisense RNAi. When antisense constructs for the two different tomato genes were each transformed into Micro-Tina tomato plants, one primary transformant with similar mutant flower phenotypes was identified from transformation of each construct. Microarray analysis shows that a similar set of genes were up- or downregulated in both mutants. Sequencing of insertion sites indicates that each is inserted into a repetitive region which could impact expression of affected genes but direct alteration of floral homeotic gene sequences was not detected.

Conclusion

This is the first report that dominant flower mutations could be caused by genetic transformation designed to knock out two nutrient stress related genes.     

Regulation of expression of two novel flower-specific genes from tomato (Solanum lycopersicum) by gibberellin.

Two flower-specific cDNAs have been isolated after differential screening of an anther cDNA library. This library was constructed 48 h after GA(3) treatment of buds of the GA-deficient gib-1 mutant of tomato. Northern blot analysis during flower development in tomato demonstrated that the expression of both genes is regulated by gibberellins (GAs). Application of GA(3) to developmentally arrested gib-1 flower buds induced new expression of tgas100 mRNA 48 h post-treatment, while an increased accumulation of tgas105 mRNA was found after 8 h. In situ analyses showed the spatial distribution of the expression of both genes within the tomato flower. One of the deduced polypeptides (TGAS105) displays similarities to cysteine-rich extensin-like proteins, while the other (TGAS100) shows significant homology with a stamen-specific gene of Antirrhinum majus. Based on the deduced protein sequences, the possible function of the encoded proteins is discussed.