影响喜树组织培养苗离体生根的因素

为了建立有效的喜树(Camptotheca acuminata)组培苗生根系统,提高其移栽成活率及适应性,用不同生长素种类及浓度、不同蔗糖浓度及不同培养基对喜树组培苗不定根形成影响以及移栽初期根系发育状况进行了研究.结果发现:1)生长素种类和浓度明显影响喜树组培苗不定根形成,在含有IBA0.5 mg·L-1培养基中取得了最佳生根效果,生根率达到了98%,外植体平均生根数为5.9条/株;2)不同浓度蔗糖对喜树组培苗生根也有一定影响,在10～30 g·L-1范围内,随着蔗糖浓度增加,生根百分率和生根数量都有增加,蔗糖浓度达到30 g·L-1时,生根百分率为95%,外植体平均生根数为5.4条/株;蔗糖浓度在40 g·L-1时,表现出对生根抑制作用;3)在基本培养基对喜树组培苗生根影响研究中发现,MS培养基对根形成表现出一定抑制作用;1/2MS和WPM培养基均适合喜树组培苗生根;4)根系发育正常的喜树组培苗移栽后成活率可达96%,但组培苗根系根毛系统发育较差.组培苗单位叶面积根尖数量显著低于对照实生苗,而且此参数与叶片气孔导度呈显著正相关.这种较差根系发育导致叶片气孔导度过低可能是组培苗叶片光合能力较低的重要原因.     

管花肉苁蓉与柽柳试管苗离体接种的研究

用去果皮的种子对柽柳长根实生苗和试管苗进行接种,建立管花肉苁蓉种子与柽柳的离体接种体系,用体视显微镜观察接种情况并用整体透明方法观察侵染情况.结果表明,寄主柽柳的试管苗与管花肉苁蓉种子的共培养能够建立管花肉苁蓉-柽柳接种复合体,这将为研究寄主-寄生物相互关系提供有效的实验体系.     

管花肉苁蓉与柽柳试管苗离体接种的研究

用去果皮的种子对柽柳长根实生苗和试管苗进行接种, 建立管花肉苁蓉种子与柽柳的离体接种体系, 用体视显微镜观察接种情况并用整体透明方法观察侵染情况。结果表明, 寄主柽柳的试管苗与管花肉苁蓉种子的共培养能够建立管花肉苁蓉-柽柳接种复合体, 这将为研究寄主-寄生物相互关系提供有效的实验体系。     

叶片生长进程中气孔发育对叶温调节的影响

鉴于气孔发育影响气孔导度和蒸腾速率,推测气孔发育可能影响叶温调节。为验证这一假设并阐述相关规律,在控光和控温条件下研究了冬青卫矛和华北紫丁香气孔发育、气孔导度、蒸腾速率及其与叶温的关系。结果表明,伴随冬青卫矛、华北紫丁香叶片生长气孔逐渐增大,但气孔密度下降;在此过程中,气孔导度和蒸腾速率逐步提高,而叶片温度降低;尽管冬青卫矛和华北紫丁香叶片的气孔密度和大小差异很小,但华北紫丁香近轴侧和远轴侧均有气孔分布,而冬青卫矛则只有远轴侧分布气孔,且相同条件下华北紫丁香的气孔导度和蒸腾速率高、叶温低。因此,气孔发育能够促进气孔导度和蒸腾速率提高,有助于降低叶温;近轴侧气孔可能更有利于蒸腾降温。     

粉葛的离体培养和无糖生根

1植物名称粉葛(Pueraria thomsonii Benth),又名甘葛藤. 2材料类别幼嫩的茎段、茎尖. 3培养条件丛芽诱导培养基:(1)MS 6-BA 0.2mg·L-1(单位下同) NAA 0.2;(2)MS 6-BA 0.5 NAA 0.2;(3)MS 6-BA 1.0 NAA 0.2.继代增殖培养基:(4)MS 6-BA 0.3 NAA 0.3;(5)MS 6-BA0.6 NAA 0.3.无糖生根培养基:(6)MS大量元素 NAA 0.2.粉葛的生根利用箱式无糖培养专利技术[1]进行,基质为蛭石,在培养基中不添加糖分,以C O2作为碳源,培养箱中C O2浓度为0.1%～0.12%,空气流速为2 L·min-1,光照度为5 000lx.在丛芽诱导和继代阶段,培养基中的糖浓度均为3.0%,琼脂的用量为6.0 g·L-1,pH 5.6～5.8.培养温度24～26℃,光照时间10～12 h·d-1,光照度1 500～2000 lx.     

不同辣椒材料离体再生及其影响因素的研究

以8个辣椒(Capsicum annuumL.)纯系为材料,对不同材料、外植体种类和激素组合等因素对辣椒植株离体再生的影响进行了研究。结果表明,较高的6-BA/IAA值有利于辣椒外植体的分化再生,而6-BA/IAA值较低则适合于再生芽的伸长;不同辣椒材料的再生能力差别较大;辣椒带柄子叶再生能力比下胚轴强,是较好的外植体材料;12~16 d苗龄的外植体分化频率较高;在供试的8个辣椒材料中‘2096’、‘B4’和‘B7’的再生能力较强。高频率的不定芽分化培养基为MB(MS无机成分 B5有机成分) 0.8 mg/L IAA 5.0 mg/L 6-BA 4.0 mg/L Ag-NO3;不定芽伸长的培养基为MB 0.8 mg/L IAA 2.0 mg/L 6-BA 2.0 mg/L GA3 4.0 mg/L AgNO3;高效生根诱导培养基为MB 0.2 mg/L IAA 0.1 mg/L NAA。     

不同基质对矮牵牛插穗离体生根的影响

用泥炭、珍珠岩和芦苇末混配的9种基质进行矮牵牛(Petunia hybrida Vilm.)离体生根实验研究.结果表明,在泥炭基质上矮牵牛插穗的生根状况较好,3个品种的平均生根率达94.4%,显著高于含苇末的各基质.在泥炭基质上扦插的各品种的主根长和根数基本都高于芦苇末基质.芦苇末基质电导率高达2.77mS·cm-1,不适宜作为扦插基质.基质电导率和插穗生根率的相关性分析表明,矮牵牛扦插基质的电导率应控制在1.5mS·cm-1以下.IAA处理表明,激素对矮牵牛插穗生根影响不明显,基质和水分管理是扦插成功与否的关键.     

鸡胚部分去壳离体培养的效果与发育观察

将２５枚产后不到２４ｈ的种蛋,依次用碘酒和７０％酒精擦拭消毒处理,去掉其钝端外壳三分之一,然后用保鲜膜封口,并以２５枚正常种蛋作为对照,按常规方法进行孵化。重复实验３次。第１次孵化,实验组的孵化率显著低于对照组（Ｐ〈０．０５）,仅为４％;第２次孵化,两组的孵化率比较接近（分别为７２％和８０％）;第３次孵化,实验组的孵化率（７６％）稍低于对照组（８８％）。３次孵化的平均孵化率,实验组和对照组分别为６     

花生胚离体发育及渗调物质的影响

在无外源激素培养基上花生胚能继续发育．渗调物质如甘露醇可抑制胚早萌,维持胚性发育,促进贮藏蛋白质合成和累积．渗调物质对胚离体发育的调控与其提高胚内源ＡＢＡ含量有关．     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.