19种菊科植物花药结构及绒毡层的发育类型研究

花药结构和绒毡层的发育类型对菊科植物的系统分类和系统演化具有重要的意义。本研究采用苏木精和苯胺番红整体染色以及石蜡切片的方法,通过显微镜观察,对菊科7族19属19种植物花药结构及绒毡层的发育类型进行研究。结果表明,18种植物的花药由4个花粉囊组成,1种由2个花粉囊组成。花粉囊壁由表皮、药室内壁、中层和绒毡层4层细胞组成,中层细胞在花粉母细胞时期解体。随着花粉粒的形成,药室内壁先“U”形增厚,再进行条带状增厚。花粉母细胞胞质分裂类型有连续型和同时型2种,小孢子四分体以四面体形为主。绒毡层的发育类型有变形绒毡层和分泌绒毡层两种类型,变形绒毡层是管状花亚科植物的共同特点,分泌绒毡层是舌状花亚科植物的共同特点。从向日葵族向菊苣族的逐渐演化过程中,绒毡层的发育类型从向日葵族的变形绒毡层、经过变形绒毡层向分泌绒毡层的过渡类型逐渐演化为菊苣族的分泌绒毡层。变形绒毡层的形态在管状花亚科不同族之间有明显差异,绒毡层的发育类型和形态可以作为亚科和族分类的依据之一。     

矿质养分和激素对根毛生长发育的影响及作用机制

【目的】植物矿质养分和水分的吸收利用赖于根系,根系中根毛的生长发育不仅扩大了根系吸收表面积,促进了矿质养分和水分的吸收还有助于植物根的固定以及与土壤微生物的互作。本文从矿质养分角度(氮、 磷、 钾、 钙、 铁)和激素角度(生长素、 乙烯、 茉莉酸、 独脚金内酯、 油菜素内酯)探讨影响根毛生长发育的因子及作用机理。【主要进展】氮对根毛生长发育的影响与茉莉酸和乙烯有关, 磷与生长素、 乙烯、 独脚金内酯互作调控根毛生长发育;生长素和乙烯以交互作用调控根毛生长发育,茉莉酸、 独角金内酯和油菜素甾醇对根毛生长发育的作用是部分依赖生长素或乙烯途径;植物体内生长素和乙烯等激素的平衡对根毛的生长发育起着重要作用。【建议和展望】基于以上分析,从蛋白激酶及其相关调控基因及转录因子等方面可深入探析矿质养分、 植物激素等对根毛和丛枝菌根生长发育的影响。     

Effect of host factors on the susceptibility of Rhododendron to Phytophthora ramorum

Phytophthora ramorum causes sudden oak death (SOD) in western coastal forests of the USA. In Europe, the pathogen is mainly present in the nursery industry, particularly on Rhododendron. Because of the primary role of Rhododendron as a host and potentially as a vector, the effect of Rhododendron host factors on P. ramorum susceptibility and sporulation was investigated. Inoculation methods using either wounded or non‐wounded detached leaves were applied to 59 Rhododendron cultivars and 22 botanical species, replicated in three separate years. All Rhododendron species and cultivars were susceptible when using wounded leaves, but not when using non‐wounded leaves, suggesting a resistance mechanism operating at the level of leaf penetration. Using a regression tree analysis, the cultivars and species were split into four susceptibility classes. Young leaves were more susceptible than mature leaves when wounded, but less susceptible when non‐wounded. This effect was not correlated with leaf hydrophobicity or the number of leaf hairs. The presence or the type of rootstock did not affect the cultivar susceptibility level. Sporangia and chlamydospore production in the leaf lesions varied widely among Rhododendron cultivars and was not correlated with the susceptibility level. The susceptibility to P. ramorum correlated well with the susceptibility to P. citricola and P. hedraiandra × cactorum, suggesting that the resistance mechanisms against these species are non‐specific. Susceptibility to P. kernoviae was low for most cultivars. These findings have implications for detection, spread and disease control, and are therefore important in pest risk assessment.     

叶片被毛对干旱区短命植物狭果鹤虱生理生态特征的影响

以荒漠短命植物狭果鹤虱为研究对象,通过野外控制实验,研究叶片被毛(leaf hairs)对狭果鹤虱生理生态特征的影响。结果表明:对于叶片有被毛的植物,模拟凝结水能显著提高叶厚、叶重、叶片水势、净光合速率、气孔导度以及地上生物量(干重),而对根径、根长与地下生物量(干重)表现出较小的效应;对于人工去除叶片被毛的植物,模拟凝结水对其根长、根径、叶厚、叶重、叶片水势、净光合速率、气孔导度、地上与地下生物量的影响不大。由此可知,被毛的存在能显著增加狭果鹤虱叶片吸附凝结水的量,同时也能增强其对干旱环境的适应能力。     

Susceptibility of sunflower inbreds to Melanagromyza minimoides in Argentina and potential association with plant resistance traits

Seed-feeding by larvae of the mosquito head fly, Melanagromyza minimoides, can substantially reduce yields of late-planted sunflower in South America and its management with insecticides or early-planting has other undesirable costs. Evaluation of inbred lines over three seasons indicated differences in the emergence of adult flies, particularly between restorer (male) and maintainer (female) lines used for hybrid seed production; when fly emergence (≈damage) was adjusted for differences in head size (i.e. to flies/100 cm²), restorer lines averaged 3–12 times more damage than maintainer lines. Fly emergence in each of two seasons was tested for correlations with three sunflower traits (glandular trichome number, pericarp strength, and sesquiterpene lactone content) believed to provide host plant resistance to other insects. In one of two years, fly emergence was negatively correlated with the relative amount of sesquiterpene lactones in florets of the tested lines. Also, among maintainer lines, severity of infestation was much greater in multi-headed inbreds compared to single-headed lines. Additional research is needed to establish the cause(s) of reduced susceptibility of inbreds and whether parental lines influence M. minimoides damage to hybrids.     

不同白肋烟品种叶面腺毛密度的动态变化

以6个白肋烟品种为材料,对烟叶成熟过程中叶面腺毛形态和密度的变化规律进行了跟踪研究.结果表明,叶面总腺毛密度随着烟叶的成熟呈下降趋势.移栽后56～86天,长柄腺毛密度逐渐减少,短柄腺毛密度明显下降.不同品种间腺毛密度差异明显,不同部位腺毛密度表现为上部叶＞中部叶.长柄腺毛是白肋烟叶片上腺毛的主要类型.随着烟叶成熟,长柄腺毛所占比例逐渐增加,腺毛头部的分泌物增多充盈,到过熟期,腺毛萎缩、衰老和脱落的速度加快.     

Research inSolanum spp. of sources of resistance to the potato tuber mothPhthorimaea operculella (Zeller)

Summary The potato tuber moth (PTM) represents a dangerous pest on potato crop in Italy, spreading out from southern areas to central and northern areas. Introductions ofSolanum berthaultii, S. commersonii, S. pinnatisectum, S. sparsipilum, S. spegazzini, S. sucurense, S. tarijense wild species andS. tuberosum × S. berthaultii hybrids were evaluated for resistance to a PTM population isolated from a field in central Italy, by means of an antibiosis test on tubers in the laboratory and of an antixenosis trial in the field. SeveralS. sparsipilum andS. pinnatisectum clones showed an antibiosis effect on larval survival and antixenosis of the aerial and the hypogeal parts of the plant. In the field, the genotypes with leaf glandular trichomes did not revcal the expected antixenosis effect of the acrial part of the plant.     

烤烟烟叶腺毛发育细胞学研究

利用常规石蜡切片技术研究烤烟烟叶长柄腺毛和短柄腺毛的形态发育过程.结果表明,烤烟烟叶长柄腺毛和短柄腺毛原始细胞均来源于原表皮,都经过两次平周分裂形成1个基细胞、1个柄细胞和1个顶细胞,两者的发生和早期发育相同,在以后的发育中,由于柄细胞和分泌细胞的不同分裂方式分别形成长柄单细胞腺头腺毛、长柄多细胞腺头腺毛和短柄多细胞腺头腺毛.     

不同部位成熟烟叶腺毛密度及其分泌物的研究

针对烟叶腺毛及其分泌物含量受烟株发育阶段的影响,采用广视野显微镜和GC/MS,分析研究了烤烟K326品种不同部位成熟叶片腺毛密度及其分泌物的变化情况。结果表明:不同部位成熟烟叶腺毛密度表现为下部<中部<上部;中部烟叶分泌物中的α-西柏三烯-4-醇、β-西柏三烯-4-醇、α-西柏三烯-4,6-二醇、β-西柏三烯-4,6-二醇的含量分别比下部烟叶增加了282%、240%、48%、80%,上部烟叶的上述四种分泌物的含量分别比下部烟叶增加了991%、687%、74%和129%。这说明对于同一烤烟品种,随部位的升高,烟叶腺毛密度增大,腺毛分泌物主要成分的含量也在增加。     

烤烟烟叶腺毛及其分泌物研究进展

烟叶腺毛密度及其分泌物对烟叶香气有重要作用,因此腺毛密度及其分泌物在烟草研究中具有重要意义。综述了烟叶腺毛类型、腺毛分泌物的主要化学成分和烟叶腺毛密度和分泌物的影响因素,以及腺毛分泌物的主要化学成分与烟叶香气的关系。展望了烟叶腺毛及其分泌物的研究方向和途径,提出烟叶腺毛及其分泌物研究的意义和目的。以期为烤烟烟叶腺毛密度及其分泌物的进一步研究提供参考。