黑木相思生根过程中可溶性糖含量与叶绿素荧光参数的变化

本试验以黑木相思两个优良无性系FM25号和四号组培苗为材料,研究生根过程中可溶性糖含量和叶绿素荧光参数的变化。结果表明:可溶性糖和叶绿素荧光参数生根前后存在很大的差异,对于FM25来说,生根过程中体内的可溶性糖含量先降后升.对于四号来说,体内可溶性糖的含量也是先降后升,再下降;生根过程中Fo的变化趋势都是先增后减再增的趋势,而荧光参数Fm、Fv/Fm的变化不同,且与生根状况存在相关性。     

黑木相思愈伤组织诱导及植株再生

以黑木相思(Acacia melanoxylon)优良单株(AMY12004)的当年新生枝条带腋芽茎段为外植体, 灭菌后接入MS培养基上培养, 以其无菌萌芽的叶片、茎段和叶柄为实验材料, 通过间接器官发生途径建立黑木相思愈伤组织诱导及高频植株再生体系。研究结果表明, 诱导愈伤组织的最佳外植体为茎段; 愈伤组织诱导的最佳培养基为MS+1.5 mg·L–16-BA+0.2 mg·L–1NAA+3%蔗糖, 诱导率为93.33%; 愈伤组织再分化的最佳培养基为MS+2.0 mg·L^–16-BA+0.5 mg·L^–1NAA+3%蔗糖, 分化率为79.17%, 再生系数为9.58; 再生芽生根的最佳培养基为MS+0.5 mg·L^–1IBA+0.5 mg·L^–1NAA+4%蔗糖, 生根率为96.05%, 移栽存活率为81.40%。     

激素对香椿腋芽增殖生长的效应

在MS基本培养其中附加不同种类的外源激素,对其在香椿芽增殖培养中的效果进行了对比试验,结果表明：单一激素对芽增殖不利,细胞分裂素是导致植株玻璃化的主要因素,只有6-BA和GA3配合使用芽增殖效果最好;GA3对6-BA有明显增效作用,既能促进芽增殖生长,又能防止、减轻玻璃化苗产生。     

木本植物快速繁殖途径及其增殖效率的影响因素

介绍木本植物快速繁殖的3种途径,即腋芽生枝、器官发生和体细胞胚发生途径。总结了木本植物快速繁殖过程中影响其增殖效率的因素,认为进行木本植物快速繁殖,应扩大取材范围、综合考虑多种因素的作用。     

黑木相思根瘤菌的系统发育分析及其结瘤效果研究

【目的】针对采集自福建、广东的34株黑木相思根瘤菌进行分类研究,进一步确定其分类地位,丰富我国黑木相思根瘤菌种质资源。【方法】对选取的34株菌株测定了16S rRNA基因、持家基因atpD和glnII序列,以14株菌为代表菌株分析其系统发育情况。而且选取了部分菌株进行结瘤实验。【结果】16S rRNA基因以及持家基因atpD和glnII的系统发育分析结果与16S rRNA PCR-RFLP分型结果基本一致,14株代表菌株被分为10个不同的类群,其中有2个群组属于中慢生根瘤菌属(Mesorhizobium),其余群组属于慢生根瘤菌属(Bradyrhizobium)。结瘤试验证明,相关的供试根瘤菌能与黑木相思、银合欢、南洋楹和网脉相思结瘤共生,显示出较广的宿主范围,且对黑木相思和银合欢的促生效果较明显。【结论】研究发现黑木相思根瘤菌具有丰富的遗传多样性和共生多样性。     

白蜡树属植物的组织培养和植株再生

从形态发生的不同途径,就有关白蜡树属植物的器官发生、腋芽增殖和体细胞胚胎发生植株再生,以及每一形态发生的培养过程和影响因素的研究进展作了介绍和展望.     

激素种类及其浓度对矮牵牛试管苗增殖及生根率的影响

以MS培养基为基本培养基,以矮牵牛试管苗为材料,并用不同浓度的细胞分裂素6-BA、KT、Ad分别与生长素NAA（0．10mg／L）进行配比试验,并用一定浓度的细胞分裂素6-BA、KT、Ad两两分别组合配比试验,探讨了不同浓度的细胞分裂素对矮牵牛试管苗的影响,以及两类生长素IBA和NAA对生根的影响。结果表明,适合于矮牵牛试管苗增殖的培养基有：（1）MS＋1．60mg／L 6-BA＋0．10mg／LNAA;（2）MS＋0．80mg／L 6-BA＋1．60mg／LKT＋0．10mg／L NAA;（3）MS＋0．80mg／L 6-BA＋0．20mg／LAd＋0．10mg／LNAA;（4）MS＋1．60mg／L KT＋0．20mg／L Ad＋0．10mg／L NAA。适合于矮牵牛试管苗生根的培养基有（1）1／2MS;（2）1／ZMS＋0．20mg／L1BA;（3）1／2MS＋0．20mg／LNAA。     

不同因素对小黄李试管苗增殖与生根的影响

以‘小黄李’砧木的单芽茎段为外植体进行离体培养,研究不同培养基、植物生长调节剂的种类及其浓度、pH值对‘小黄李’增殖与生根的影响。结果表明:较合适的增殖培养基为F14 0.8mg·L-16-BA 0.2mg·L-1NAA 30g·L-1蔗糖 6g·L-1琼脂,pH值5.4~5.8;较合适的生根培养基为改良MS 0.1mg·L-1NAA 0.2mg·L-1IBA 30g·L-1蔗糖 6g·L-1琼脂,生根率达100%,单株平均根数3~4根;以蛭石∶珍珠岩∶泥炭(1∶1∶1)移栽生根苗,成活率达80%以上,实验结果为工厂化育苗生产奠定了基础。     

外施植物生长调节剂对山荆子扦插生根的影响

目的:本研究旨在筛选适宜山荆子硬枝扦插生根的植物生长调节剂配方,从生理水平探讨其促进扦插生根原因.方法:采用萘乙酸(NAA)、3-吲哚丁酸、双吉尔的不同浓度处理,对插穗生根效果及生理生化指标动态测定.结果:300 mg·L-1 NAA处理的插穗生根效果最佳,生根率83％,生根数23.7条,分别为对照组的3.6倍、6.2...     

黑木相思优良无性系叶片数量性状与生长评价

为合理利用种质资源,对5年生黑木相思(Acacia melanoxylon)无性系试验林中9个优良无性系(F1、SR3、SR9、SR14、SR17、SR18、SR25、SR38、SR41)开展叶片和生长性状的遗传变异研究,采用模糊数学隶属函数值法进行综合评价。结果表明,9个无性系叶片在形态、结构、化学性状都存在显著差异,以形态性状变异系数最大,其中叶面积(LA)和叶宽(LW)可作为直观区别无性系的可靠指标。SR18、SR17和SR14号无性系的树高(H)和胸径(DBH)生长具有显著优势。相关性分析表明,LW与H,LW、LA、比叶面积(SLA)与DBH呈显著线性关系,而叶长(LL)、干物质量(LDMC)、C、N、P、C/N和N/P与H和DBH相关性弱。隶属函数综合评价排名前4位的是SR17、SR18、SR41、SR14,可作为直接生产和后续育种工作的有效资源加以应用。     

Changes in Concentrations of Cytokinins (CKs) in Root and Axillary Bud Tissue of Miniature Rose Suggest that Local CK Biosynthesis and Zeatin-Type CKs Play Important Roles in Axillary Bud Growth

Involvement of cytokinins (CKs) in axillary bud growth of miniature rose was studied. Variation in root formation and axillary bud growth was induced by two indole 3-butyric acid (IBA) pretreatments in two cutting sizes. At six physiological developmental stages around the onset of axillary bud growth, concentrations of CKs were determined in both root and axillary bud tissue by liquid chromatography combined with electrospray tandem mass spectrometry (LC-ESP-MS/MS). Chronological early onset of axillary bud growth occurred in long cuttings pretreated at low IBA concentration, whereas physiological early root formation was associated with long cuttings and high IBA concentration. The CKs zeatin (Z), isopentenyl adenine (iP), zeatin riboside (ZR), dihydrozeatin riboside (DHZR), isopentenyl adenosine (iPA), zeatin O-glucoside (ZOG), zeatin riboside O-glucoside (ZROG), zeatin riboside 5′-monophosphate (ZRMP), and isopentenyl adenosine 5′-monophosphate (iPAMP) were detected. Concentrations of CKs in axillary bud tissue far exceeded those in root tissue. Indole 3-butyric acid pretreatment influenced the concentration of CKs in axillary bud tissue more than did cutting size, whereas pretreatments only slightly affected CKs in root tissue. The dominant CKs found were iPAMP and ZR. An early and large increase in iPAMP indicated rapid CK biosynthesis in rootless cuttings, suggesting that green parts, including the axillary bud, can synthesize CKs. At the onset of axillary bud growth an increase in concentration of Z, ZR, ZRMP, ZOG, and ZROG was largely coincident with a decrease in iPAMP, iPA, iP, and DHZR. After the onset of axillary bud growth, CK content largely decreased. These results strongly indicate a positive role for CKs in axillary bud growth, and presumably ZRMP, ZR, and Z are active in miniature rose.     

施盐和磷对台湾相思幼苗光合作用及养分特征的影响

为探究施盐和磷对重要海防林树种台湾相思幼苗叶光合作用与养分特征的影响,该研究设置0%(B₀)、0.2%(B₁)、0.4%(B₂)、0.6%(B₃)、0.8%(B₄)的NaCl溶液和0 (P₀)、0.5 (P₁)、1.5 (P₂)g·kg^-1 3个供磷水平的过磷酸钙磷肥,在此基础上设置盐磷6个耦合处理,测定幼苗光合作用和养分特征指标。结果表明：(1)盐胁迫显著抑制台湾相思幼苗的生长发育,盐含量越高影响程度越大;低盐施磷对台湾相思幼苗生长不利,中高盐施磷显著减缓盐对幼苗生长的抑制作用。(2)台湾相思幼苗光合作用受盐胁迫影响显著;中低盐施磷后气孔关闭程度上升会加剧盐胁迫对幼苗光合作用的影响,高盐适当施磷可显著提高台湾相思幼苗光合能力。(3)盐胁迫显著降低叶绿素含量且对光系统Ⅱ造成危害;低盐胁迫施磷对台湾相思幼苗叶绿素合成不利,高盐适当施磷可以提高叶绿素合成量、稳定细胞膜结构以及提高叶片潜在光合能力...     

盐磷胁迫对木麻黄和台湾相思种子萌发及幼苗生长的影响

恶劣环境下,人工海防林因面临养分胁迫而经营困难。为探讨盐、磷胁迫对主要海防林树种木麻黄和台湾相思种子萌发及生长的影响,该研究分别用不同浓度的NaCl(盐)和KH₂PO₄(磷)溶液处理种子和浇灌幼苗,测定种子萌发和幼苗生长指标。结果表明：(1)高盐胁迫显著抑制种子萌发,对幼苗生长有一定影响,但两种植物影响程度不同;台湾相思种子萌发耐盐性高于木麻黄,前者相对盐害率最大值为23.03%,后者为89.15%;随着盐浓度增加,木麻黄和台湾相思种子的发芽率、发芽势、发芽指数和活力指数均降低,对应最大值分别为38.70%、34.67%、18.70、0.055和76.67%、62.22%、48.46、6.11。(2)两种植物的株高和根长随盐浓度增加而降低,木麻黄和台湾相思株高分别为12.29～6.01 mm和48.27～17.33 mm,根长分别为8.57～1.45 mm和33.41～5.88 mm;台湾相思根、茎、叶生物量及根冠比均随盐浓度的增加逐渐减小,木麻黄各处理差异较小。(3)台湾相思的种子和幼苗较木麻黄更耐低磷环境,二者最适磷浓度存在差异;木麻黄种...     

Cd污染及其与大气CO2浓度升高、N添加复合作用对大叶相思生长的影响

为了解Cd污染胁迫下树木对CO_2浓度升高、N添加及其复合作用的响应,应用开顶箱,探讨Cd及其与CO_2、N的复合作用对大叶相思(Acacia auriculiformis)基径、树高和生物量的影响。结果表明,Cd添加抑制大叶相思基径、树高和生物量的增长,并且具有时间滞后性;大气CO_2浓度升高、N添加及CO_2+N均有缓解Cd对植物生长抑制作用的趋势,其中, N添加更能促进大叶相思基径的生长,树高生长则对CO_2升高更为敏感;在Cd污染土壤中,N添加的缓解作用最显著。因此,氮肥管理是重金属污染土地修复初期促进植物修复的重要策略。     

The introduction and release of Chiasmia inconspicua and C. assimilis (Lepidoptera: Geometridae) for the biological control of Acacia nilotica in Australia

Two geometrid moths Chiasmia inconspicua and Chiasmia assimilis, identified as potential biological control agents for prickly acacia Acacia nilotica subsp. indica, were collected in Kenya and imported into quarantine facilities in Australia where laboratory cultures were established. Aspects of the biologies of both insects were studied and CLIMEX® models indicating the climatically favourable areas of Australia were developed. Host range tests were conducted using an approved test list of 74 plant species and no-choice tests of neonate larvae placed on both cut foliage and potted plants. C. inconspicua developed through to adult on prickly acacia and, in small numbers, Acacia pulchella. C. assimilis developed through to adult on prickly acacia and also in very small numbers on A. pulchella, A. deanei, A. decurrens, and A. mearnsii. In all experiments, the response on prickly acacia could be clearly differentiated from the responses on the non-target species. Both insects were approved for release in Australia. Over a three-year period releases were made at multiple sites in north Queensland, almost all in inland areas. There was no evidence of either insect’s establishment and both colonies were terminated. A new colony of C. assimilis was subsequently established from insects collected in South Africa and releases of C. assimilis from this new colony were made into coastal and inland infestations of prickly acacia. Establishment was rapid at one coastal site and the insect quickly spread to other infestations. Establishment at one inland area was also confirmed in early 2006. The establishment in coastal areas supported a CLIMEX model that indicated that the climate of coastal areas was more suitable than inland areas.     

Biological control of an alien tree, Acacia cyclops, in South Africa: impact and dispersal of a seed-feeding weevil, Melanterius servulus

Several Australian Acacia species have become highly invasive in a number of ecologically sensitive areas of South Africa. Many have useful attributes that, to an extent, have hampered biocontrol efforts by restricting potential agents to those reducing seed production whilst not affecting vegetative growth. The outcome of the introduction of a seed-feeding weevil, Melanterius servulus, against Acacia cyclops in 1994, was assessed by investigating the plant’s reproductive phenology, as well as levels of damage caused by the beetles. The study provided essential information on host/agent interactions and, on the build up and spread of populations of the agent. Seed damage is commonly as high as 90% (exceptionally it reaches 100%), and dispersal rates of the beetles on average is almost 2 km per year. The consistently high levels of seed damage achieved hold promise for the future of the program, however, its ultimate success will be further enhanced through the integration of biological control with other manual clearing operations that are currently employed on a large scale in South Africa.     

生长调节剂对黄连木光合生理指标和荧光参数的影响

以黄连木幼苗为试材,采用叶片喷施的方法,研究了生长调节剂多效唑和矮壮素对黄连木叶片解剖结构、色素含量、光合生理指标和叶绿素荧光参数的影响,以揭示生长调节剂对黄连木光合特性的影响及其内在机制。结果显示:随着两种生长调节剂处理浓度的增加,黄连木幼苗叶片厚度、栅栏组织厚度、海绵组织厚度、色素含量、净光合速率(Pn)、PSⅡ原初光能转化效率(Fv/Fm)、PSⅡ的潜在活性(Fv/F0)、叶片单位面积吸收的能量(ABS/CS)和捕获的能量(TRo/CS)以及电子传递的能量(ETo/CS)均呈先增大后减小的趋势,并均在800mg/L多效唑和500mg/L矮壮素处理时达到最大值,且显著提高了黄连木叶片的净光合速率。研究发现,黄连木幼苗叶片栅/海比例增大和叶绿素含量的增加使叶片对光能的捕获和吸收能力提高,而PSⅡ反应中心开放比例的增大与其活性的增强保证了叶片对光能的高效传递,同时降低了能量的热耗散,是提高苗木光合速率和保证苗木光合作用高效进行的内在机制。