几种细胞分裂素和生长素对杜仲下胚轴离体培养的影响

培养在附加不同种类的激素和不同激素浓度组合的 MS 基本培养基上的杜仲下胚轴切段,能诱导出愈伤组织,但诱导出的愈伤组织的生物产量及芽数不同:1.含0.2mgL~(-1)～2mgL(-1)BA 和2mgL(-1)ZT的 MS 培养基上,外植体诱导出了愈伤组织和芽,而在附加2mgL(-1)KT 的 MS 培养基上,外植体只能诱导出愈伤组织。2.在 MS+8mgL(-1)BA 的培养基上,只有愈伤组织的产生而无芽的分化,说明8mgL(-1)BA 抑制了芽的发生。3.MS+2mgL(-1)BA+0.2mgL(-1)生长素(NAA、IAA、IBA)的培养基,能促进外植体诱导出愈伤组织,也能分化出芽。     

The Translocation of 14C-Sucrose and 14C-Benzyl Adenine in Winter Wheat (Tritkum aestivum L.) in the Period of Kernel Formation

The transport and distribution of ^14C-sucrose and ^14C-BA were studied in internode segments with ear of two winter wheat cultivars with a different mass of kernels in the period of kernel formation. While ^MC-sucrose was transported and accumulated intensively in the developing ear, ^14C-BA was transported much less and only a small part of it was found in the ear. With the ear development the accumulation of both ¹⁴C-sucrose and ¹⁴C-BA in the ear increased but the ¹⁴C-BA distribution pattern (ratio of the internode/kernel and the rest of the ear) did not change significantly. In the period of one to two weeks after anthesis the accumulation of ¹⁴C-sucrose and ¹⁴C-BA was higher in the kernels of the Slavia cv., i.e. in the cultivar with a higher mass of kernels.     

苹果细胞分裂素O–糖基转移酶基因MdZOG1的分离与功能鉴定

以‘嘎拉’苹果为材料,采用同源克隆和PCR技术分离了苹果细胞分裂素O–糖基转移酶基因MdZOG1。MdZOG1的开放阅读框(ORF)长度为762bp,编码含有253个氨基酸的蛋白。系统进化树分析显示,MdZOG1与PbZOG1亲缘关系最近。基因表达分析显示MdZOG1主要在苹果根和茎中表达,在花和果实中的表达量较低。通过农杆菌介导的遗传转化获得转MdZOG1拟南芥和烟草。干旱处理试验结果显示:超量表达MdZOG1显著提高拟南芥和烟草植株的抗旱能力,表明苹果细胞分裂素O–糖基转移酶在植物抗旱胁迫中发挥重要作用。     

Development of a regeneration protocol through indirect organogenesis in prickly pear cactus (Opuntia ficus-indica (L.) Mill)

An indirect organogenesis regeneration protocol for Opuntia ficus-indica (L.) Mill var “Blanco sin Espinas” is described. One centimeter square cladode explants sections from previously micropropagated prickly pear plants were cultured in Murashige and Skoog (MS) basal medium supplemented with 20 different combinations of 2,4-dichlorophenoxy acetic acid (2,4-D) and benzyladenine (BA). The best calli induction and regeneration response were observed when 2.26 μM 2,4-D and 2.21 μM BA combination was applied to the nopal explants. Regenerating calli was capable of forming new buds when transferred to MS basal medium supplemented with 0.5 μM BA (proliferation medium). Shoot elongation and rooting were achieved on MS medium without plant growth regulators. Excellent acclimatization to greenhouse conditions was observed for all transferred plantlets. By this procedure no morphological differences were observed between the regenerated and mother plants. This protocol may be also utilized to carry out plant regeneration after genetic transformation, in order to develop transformed plants without the presence of chimeric zones.     

Premature seed germination induced by very-long-chain fatty acids causes jelly seed disorder in the mango (Mangifera indica L.) cultivar ‘Amrapali’ in India

Jelly seed (JS) in ‘Amrapali’ mango (Mangifera indica L.) is a physiological disorder, the cause of which has long remained obscure. The disorder is distinguished by the appearance of jelly-like tissue in the pulp adjoining the stone, although the fruit show no external symptoms. The objective of this study was to determine the causative factor inducing the JS disorder in ‘Amrapali’ mango. Studies showed, for the first time, that JS in ‘Amrapali’ mango arose at the start of germination-associated events in the seed of developing fruit. The trigger for premature seed germination originated from reduced synthesis of very-long-chain fatty acids (VLCFAs) in the seed of developing fruit. This then promoted the production of cytokinins, leading to the onset of premature germination-associated events in the seed. Consequently, a large increase in the activities of pectinolytic enzymes in JS pulp occurred that led to the rapid degradation of pectin and excessive softening of the pulp, to the consistency of jelly. The application of plant growth regulators to developing fruit showed that gibberellic acid (GA₃) increased the incidence of JS, while paclobutrazol reduced the incidence of JS, confirming that the onset of early germination during fruit maturation and ripening played a primary role in the incidence of the JS disorder.     

‘巨峰’葡萄细胞分裂素氧化酶基因CKX3的克隆与表达分析

结合同源克隆和RACE技术在‘巨峰’葡萄（Vitis labruscana Bailey × V. vinifera L.‘Kyoho’）中克隆了细胞分裂素氧化酶基因CKX3,分析了该基因的表达特性及其对细胞分裂素的响应。序列分析表明,该基因cDNA全长为2 049 bp（GenBank登录号：KP689597）,ORF（开放阅读框）为1 569 bp,编码522个氨基酸,具有FAD（黄素腺嘌呤二核苷酸）结合结构域和细胞分裂素结合结构域。该基因定位在葡萄的7号染色体上,具有4个内含子,5个外显子。氨基酸序列多重比对和系统进化树分析显示‘巨峰’葡萄CKX3与荷花NuCKX3亲缘关系最近,与毛果杨同源性较高。基因表达分析结果显示‘巨峰’葡萄CKX3主要在根部和花序中大量表达,其次是在卷须和果实中有较高的表达,在茎和叶中的表达量较低;在花序发育过程中,在盛花期前表达量较低,盛花期以及盛花后表达量增加。在6-BA处理葡萄叶片后,CKX3的表达与细胞分裂素氧化酶的活性都高于对照。     

杂环脲类细胞分裂素混剂对白肉火龙果经济性状的影响

以白肉火龙果为试材,探讨杂环脲类细胞分裂素混剂对果实经济性状的影响,结果表明:(1)果实纵横径和单果重均比对照有极显著的增加,以10 mg·L-1喷2次处理效果最好;(2)果实可溶性固形物(TSS)含量均极显著地高于对照,其中喷2次比1次效果好.     

喷施细胞分裂素对长豇豆产量及生理生化指标的影响

为提高长豇豆产量,在塑料大棚直播栽培条件下,以长豇豆柳翠、早翠、矮虎和地豆为材料,进行随机区组试验。在现蕾期叶面喷施细胞分裂素,分别于喷后7d、14d、28d和42d取豇豆三出复叶的中间小叶测定叶绿素、丙二醛、脯氨酸和可溶性糖等生理生化指标,并比较喷施前后长豇豆的产量和叶片生理生化指标。结果表明:喷施细胞分裂素后7d和28d各长豇豆品种叶片中游离脯氨酸含量比各对照品种分别提高89.04%和73.44%,差异极显著;喷药后28d和42d各长豇豆品种叶片中可溶性糖含量比各对照品种分别提高72%和45.85%,差异极显著;喷药后14d和28d各长豇豆品种叶片中丙二醛含量比各对照品种分别降低25.21%和28.22%,差异极显著;喷药后42d各长豇豆品种叶片中叶绿素含量比对照品种提高47.65%,差异极显著。喷药后,各长豇豆品种的产量均高于对照,喷施后平均增产13.99%,差异极显著。喷施细胞分裂素能有效提高叶片游离脯氨酸、可溶性糖和叶绿素的含量,降低丙二醛含量,从而达到增产效果。     

转IPT基因水稻的抗旱性研究

水稻抗旱性研究是当前水稻研究的热点。采用农杆菌介导法将IPT基因导入籼稻IR64,并获得了254株再生植株,并对其进行PCR检测和Southern杂交分析,确定目的基因已整合到水稻中。选择两个单拷贝的转基因株系和一个野生型株系在开花期对其进行干旱胁迫,在同等水平干旱胁迫条件下,IPT转基因植株的细胞分裂素含量和叶绿素含量明显高于野生型,叶片温度稍微低于野生型,且转基因植株茎叶衰老延缓,这些结果表明IPT基因在抗旱育种及机理研究方面有积极的研究意义。     

CTK5406对Ⅰ-69杨光合作用和生长的影响

试验以I-69杨Populus deltoides Bartr.cv.“lux”(I-69-55)为材料,研究了植物细胞分裂素制剂(CTK5406)对I-69杨光合作用和生长的影响,苗木分别培养于人工气侯宝和自然光下,结果表明,CTK5408对I-69杨的光合作用和生长具有明显作用。其中以施用量1g/1.5L(水培)和3g/10L(沙培)促进效果最好,使净光合速率提高16％,使生物量积累提高22％～28％。实际生产中由于田间多种因素的影响,施用量可取高限3g/株,直接埋入土中或与肥料一起施用。