蚕豆叶片气孔对甲醛污染的反应研究

[目的]探讨植物气孔对甲醛污染的响应机制,筛选对甲醛降解能力强的室内绿化植物,利用植物对甲醛污染进行监测。[方法]采用密闭反应仓法研究蚕豆叶片气孔对不同浓度甲醛污染处理的响应。[结果]2种蚕豆幼苗叶片气孔的长度和宽度均随甲醛浓度的增加和处理时间的延长而变小。松滋青皮蚕豆品种的叶片经甲醛污染处理24 h后,虽然气孔的面积比对照减小,但差异未达显著水平(P>0.05),但是随着处理时间的延长,2种蚕豆的气孔面积与对照相比均达显著差异水平(P<0.05)。[结论]普通蚕豆叶片气孔对甲醛污染的反应比松滋青皮蚕豆叶片气孔的反应更敏感。     

玉米与大豆间作对玉米叶片气孔及光合效率的影响

 气孔是植物进行气体、水分交换与代谢,响应环境条件,包括病菌侵染的重要通道,其大小、密度和分布既受到遗传的控制,也受到生长环境的影响。为了研究玉米与大豆间作对玉米叶片气孔的影响,笔者采用改良刮制法对玉米叶片下表皮的气孔器长度、宽度和密度进行了观测。结果表明,与净作玉米相比,间作玉米植株上部、中部和下部叶片的气孔密度较净作显著降低,而气孔器长度较净作显著增加;植株中、下部叶片的气孔器宽度也较净作显著增加,植株上、中、下部叶片的光合速率和蒸腾速率都较净作显著增大。这些结果表明,间作对玉米气孔的影响是系统性的,而且气孔这些特征的变化是有利于提高产量、减少叶斑病发生的。     

黄秋葵和红秋葵的细胞学研究

对黄秋葵和红秋葵的染色体数目和气孔进行了研究,结果表明,黄秋葵染色体数目为2n=7x=126,红秋葵为2n=7x=133;两者的气孔形态、密度和叶绿体数均无显著差异。     

荔枝、龙眼叶片表皮结构的研究

 用扫描电镜观察了荔枝、龙眼各3个品种的叶表皮。结果表明, 龙眼叶片上表皮角质层平均厚度2.36μm , 显著大于荔枝(1.93μm) 。荔枝、龙眼叶片下表皮具有大量的乳状突; 乳状突的密度, 荔枝为7 855.1个/mm² , 龙眼为7 708.8个/mm² ; 荔枝的乳状突呈近半圆形, 宽9.55μm, 高5.71μm; 龙眼的乳状突为长形, 宽5.94μm, 高10.38μm; 荔枝、龙眼气孔长×宽分别为6.98μm ×3.09μm、7.14μm×2.30μm。荔枝、龙眼表皮结构特征差异明显。     

植物气孔发育分子机制研究进展

气孔作为植物生长发育所必需的重要因素,是植物与外界环境进行气体和水分交换的通道,在调节植物光合作用、蒸腾作用以及水分利用中具有非常重要的作用。气孔的形成与发育受到转录因子的调控,包括b HLH类转录因子、MYB类转录因子和Dof转录因子,同时受到一系列负调控因子、蛋白激酶及受体蛋白的影响。另外,气孔的发育还受CO_2浓度、光照及激素等环境因子的影响。这些因素在某种程度上相互作用,共同决定植物气孔的形成、分布、生长及发育过程。该研究综述了近年来气孔发育相关的研究进展,总结了参与气孔发育的相关因子,并且对未来研究需要解决的问题进行简要的讨论。     

In vitro tetraploid induction via colchicine treatment from diploid somatic embryos in grapevine (Vitis vinifera L.)

A protocol for in vitro induction of tetraploids via colchicine-treated somatic embryos from immature zygotic embryos of diploid grapevine (Vitis vinifera L.) is reported. Embryogenic callus was initiated from immature zygotic embryos cultured on Nitsch and Nitsch (NN) medium supplemented with 1.0 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D). The callus was transferred to NN medium containing 1.0 mg/l α-naphthalene acetic acid (NAA) and 0.5 mg/l benzyladenine (BA) to establish somatic embryogenesis. The vigorously growing globular embryos were selected and treated by 0, 10 or 20 mg/l colchicine for 1, 2 or 3 days, and then immediately transferred to NN medium supplemented with 0.03 mg/l NAA and 0.5 mg/l BA, for somatic embryo conversion and plant regeneration. The number of surviving embryos and regenerated plantlets following colchicine treatment decreased with increasing colchicine concentration and treatment time. Among 29 randomly investigated plantlets regenerated from colchicine-treated somatic embryos, five solid tetraploids (2n = 4× = 76) were identified by chromosome counting analysis; all others were diploid (2n = 2× = 38). Ploidy level of plant regenerated was also determined from leaves using flow cytometry. No chimeras with both 2C and 4C nuclei was produced from colchicine-treated somatic embryos. Significant differences in leaf stomata parameters were observed between diploid and induced tetraploid plantlets.     

秋水仙素诱导山东丹参丛生芽多倍体的研究及鉴定

[目的]探究秋水仙素对山东丹参丛生芽诱导的可行性。[方法]采用秋水仙素处理方法诱导山东丹参丛生芽。[结果]添加12mg/L秋水仙素时,多倍体诱导率最高（36.6%）,存活率只有16.7%;添加8 mg/L秋水仙素时,多倍体诱导率为15.9%,成活率最高（40.0%）。多倍体山东丹参的植株粗壮,叶片大而厚,颜色深,叶片下表皮上的气孔密度小,长度长。[结论]秋水仙素能有效诱导丛生芽,并获得了丹参多倍体育种材料,为缩短育种进程奠定了基础。     

Faba bean breeding for drought-affected environments: A physiological and agronomic perspective

The faba bean (Vicia faba L.) crop often experiences drought during its growth and development such that soil moisture deficits constrain its production. As droughts are predicted to increase in both frequency and intensity due to climate change, a better understanding of drought response patterns and associated traits is essential for obtaining yield stability in water-limited environments. This review deals with adaptation mechanisms associated with drought avoidance, escape and tolerance, with an emphasis on physiological traits such as stomatal conductance, carbon isotope discrimination and leaf temperature. Leaf temperature is considered an effective surrogate measure for other measures of stomatal characteristics. Drought tolerance through osmotic adjustment has not yet been demonstrated in faba bean although it is found in many other legumes including chickpea and pea. Deeper root growth, leading to uptake of otherwise unavailable water, helps the plant to avoid drought by delaying dehydration, but genetic variation and heritability of the trait are essentially unknown for faba bean. Crop management strategies, such as early planting, and appropriate phenology, are particularly important for drought escape in regions where terminal drought is common. Disease resistance is especially important in drought-prone areas to reduce the need for expensive control measures when yields are uncertain. The relevance of soil fertility status and nutrient availability are also covered. Drought escape and ascochyta blight resistance are important breeding objectives for terminal drought regions. Some form of drought resistance is necessary for the transient droughts experienced in most regions, and drought avoidance can be screened by a combination of leaf temperature or other rapid test of stomatal characteristics followed by carbon isotope discrimination in the most valuable materials. No single trait is adequate to improve yield in drought-prone environments, rather, a combination of characteristics is needed.     

叶片表皮指纹在杜鹃花属分类中的意义

本实验于2004年在东北林业大学进行。用指甲油印记法在光学显微镜下观察了杜鹃花属6个种(牛皮杜鹃 Rh.aureaum,兴安杜鹃Rh. dauricum, 照白杜鹃Rh. micranthum,迎红杜鹃Rh. mucronulatum,苞叶杜鹃 Rh. Redowskianum 和大字杜鹃Rh. schlippenbachii)的表皮指纹特征。对叶片的形态特征包括叶片下表皮气孔类型、保卫细胞和副卫细胞的特征、叶片两面的普通细胞(形状和垂周壁特征)和表皮毛进行了较详细的描述。所研究的6种杜鹃花中,有3种气孔类型,其中兴安杜鹃、照白杜鹃、和迎红杜鹃为单细胞型气孔(Pericytic 型),苞叶杜鹃为不规则型气孔(Anomocytic 型),牛皮杜鹃和大字杜鹃是平轴式气孔(Diacytic 式)。不同种间,单细胞型和平轴式气孔的副卫细胞类型在形状和表面特征上有所不同。普通表皮细胞的表面观为从四边形、六边形, 多边形或不规则型, 垂周壁呈平直或弯曲状。兴安杜鹃、照白杜鹃和迎红杜鹃3种的叶片两面均有腺鳞。所有这些叶片特点表明上述6种杜鹃花的表皮指纹具有种的特性。图4表2参29。     

濒危植物南方红豆杉叶片形态结构及气孔参数

用光学显微镜观察了南方红豆杉叶片形态结构。结果表明:南方红豆杉叶片上、下表皮细胞近长方形或正方形,均覆盖一层角质层,角质化程度不同,角质层平均厚度分别约为14.78μm和12.53μm。在同一叶片的不同区域,叶表皮细胞形状及大小变化较大,叶中脉处的表皮细胞最大,为152.20μm×37.59μm,长/宽约为4.05;气孔区的表皮细胞形状不规则,细胞大小起伏较大,最大细胞为154.8μm×29.6μm,最小为43.1μm×47.1μm,平均大小为83.89μm×45.31μm,长/宽约为1.85;非气孔分布区的表皮细胞平均大小为99.13μm×40.17μm,长/宽约为2.47。气孔仅分布于下表皮中脉两侧,呈带状,每条气孔带含8~12列气孔,气孔密度为98~159个/mm2。雌雄植株不同高度叶片的气孔密度均从基部到株顶呈逐渐增加的趋势,但雌雄植株同一高度叶片的气孔密度变化差异不大。在同一高度的叶片中,阳面叶片的气孔密度普遍高于阴面叶片;在同一叶片中气孔密度最高的区域在叶片的中部,向两端逐渐减少,与叶片着生植株的雌雄、方位和高度无关。