影响四季桂插穗生根若干因子研究

本文研究扦插基质、插穗枝梢成熟度和插穗留叶量对四季桂生根的影响。结果表明:枝梢成熟度和扦插基质对插穗生根有显著影响,留1片叶和留2片叶对插穗生根没有显著影响。因此,四季桂扦插宜选用半木质化成熟枝梢,并采用2/3泥炭土+1/3珍珠岩作为扦插基质,留1～2片叶效果最好。     

裸花紫珠嫩枝扦插生根影响因子研究

以2年生实生苗的嫩枝为试材,从基质、插条部位、留叶方式、扦插季节、外源激素种类及浓度5个方面对裸花紫珠的扦插生根因子进行了系统研究。测定插穗的生根率、偏根率、生根数量及最大根长,采用隶属函数值对扦插生根效果进行综合评价。结果表明:(1)8个基质处理中,以泥炭∶蛭石∶河沙按2∶1∶1体积比混合的基质扦插效果最好,生根率74%,平均生根数5.4条;(2)插条中、上部制取的插穗扦插效果优于下部,且中部插穗的生根质量最佳;(3)插穗留叶处理的生根率显著高于不留叶处理,留两片半叶(1/2叶)时,生根率可达64%;(4)秋季(9月)为扦插最适宜季节,生根数量和最大根长均显著高于春季(4月)和夏季(7月);(5)4个浓度下,IBA处理的生根质量均高于IAA和NAA处理,其中IBA(1 000、1 500 mg·L~(~(-1)))处理的扦插效果较好,而高浓度NAA(2 000、2 500 mg·L~(~(-1)))处理明显不利于生根。     

不同基质对多穗石柯扦插生根的影响

为了筛选适宜的多穗石柯(Lithocarpus polystachyus)扦插基质，以半木质化枝条为插穗，选取5种原料(园土、黄心土、泥炭土、河沙、椰糠)设置8个基质配方，并对各基质容重、总孔隙度、pH、电导率进行测定，探讨不同基质对多穗石柯扦插成活率、生根数量及根系长度的影响。结果表明，不同配方基质的理化性质不同，多穗石柯扦插成活率、根系数量和根系长度具有显著性差异；成活率、根系数量和根系长度与基质的理化性质存在显著相关，总孔隙度大的基质不利于多穗石柯扦插成活和根系生长，pH和电导率较低的基质中多穗石柯扦插成活率较高；基质园土:黄心土:河沙(1:1:1)最适宜多穗石柯扦插繁殖，扦插成活率最高，为86.75%，其次是基质黄心土:河沙(2:1)。     

年龄效应对白杨硬枝扦插苗生长及其茎皮部解剖结构和叶片生化指标的影响

为探究白杨年龄效应导致的扦插繁殖苗退化问题,该试验以杂种三倍体‘北林雄株2号’的不同年龄苗木硬枝插穗为材料,就扦插苗生长形态、光合生理、根发育特征、插穗皮部解剖结构以及苗木生长发育过程中叶片可溶性总糖(TSS)、可溶性总蛋白(TSP)、叶绿素(Chl)、脯氨酸(Pro)、赤霉素(GA)、生长素(IAA)、脱落酸(ABA)及IAA/ABA比值等生理生化指标进行了观测。结果表明:(1)再生苗苗高、地径、叶柄长度、节间宽、叶面积、主根数、主根长、生根率、根系效果指数及净光合速率(P_n)等指标均随插穗年龄的增加而降低,而其侧根数、侧根长、胞间CO_2浓度(C_i)、气孔导度(G_s)和蒸腾速率(T_r)等指标与插穗年龄无明显相关性。(2)插穗茎皮部解剖结构显示,周皮和木质部厚度都随插穗年龄增大而增厚,韧皮部厚度则无明显变化。(3)再生苗叶片可溶性总糖、总蛋白、叶绿素、IAA、GA含量以及IAA/ABA比值等指标均随插穗年龄的增加而逐渐降低,而脯氨酸和ABA含量则随插穗年龄增加而增加。研究发现,白杨扦插苗随插穗年龄的增加累积成熟效应,使新生苗表现出整体性衰老的生长状态。     

静电场处理对垂枝樱花插穗生根及相关生理生化特性的影响

以垂枝樱花为材料,设置1.5、3.0、4.5、6.0kV/cm共4种场强的静电场处理,分析静电场对垂枝樱花插穗生根性状及相关生理、生化特性的影响,探讨静电场促进垂枝樱花插穗生根的机制。结果显示:(1)1.5～4.5kV/cm场强的静电处理能显著提高插穗的可溶性蛋白、可溶性糖含量,且4.5kV/cm处理的增幅最大,峰值时比对照分别增加43%和44.1%;(2)1.5～4.5kV/cm场强的静电场处理能显著提高插穗的过氧化物酶(POD)活性,降低吲哚乙酸氧化酶(IAAO)活性,且4.5kV/cm处理的效果最明显,与对照相比增幅和降幅最大时分别达到58.9%和17.5%;(3)3.0、4.5kV/cm的静电场处理均能够显著提高插穗的平均单株生根数、根系平均长度、单株根鲜重、根系活力以及插穗成活率,且4.5kV/cm处理的增幅最大,与对照相比分别增加了127.4%、29.2%、88.9%、107.1%、116.3%。研究表明,静电场处理可以有效调节垂枝樱花插穗的可溶性蛋白、可溶性糖的含量以及POD、IAAO的活性,能显著提高插穗的扦插成活率,其最佳静电场场强为4.5kV/cm。     

花叶夹竹桃穴盘扦插繁殖技术研究

采用L₉(3⁴)正交试验设计,研究插穗类型(A)、生长调节剂种类(B)及其浓度(C)对花叶夹竹桃插穗生根和苗木生理指标的影响。结果表明,影响花叶夹竹桃插穗生根和扦插苗生理指标的主要因素是插穗类型和生长调节剂种类;筛选出花叶夹竹桃扦插的最佳组合为A₁B₁C₁,即以木质化程度较轻的上部枝条作为插穗,用200 mg/L NAA处理,进行扦插育苗效果最好。     

草珊瑚扦插技术研究

采用4因素3水平L_9(3~4)正交试验法,以生根率、生根数和平均根长为生根效果的评价指标,研究扦插基质、萘乙酸、吲哚丁酸、插穗部位对草珊瑚Sarcandra glabra扦插生根效果的影响。结果表明,插穗部位对草珊瑚扦插生根效果影响最大,其次是扦插基质,吲哚丁酸对扦插生根有抑制作用,萘乙酸则没有显著影响。草珊瑚扦插繁殖时用顶部插穗,扦插基质采用含沙黄土生根效果最好,生根率达98.12%,生根数每棵12.11条,平均根长8.31 cm。     

芳樟穗条性状对扦插成活率的影响

利用温室大棚进行芳樟容器扦插育苗试验。结果表明,芳樟穗条性状对扦插成活率的影响显著或极显著,同一枝条梢部穗条的扦插成活率显著高于中部、下部和基部;穗条长度10 cm、直径0.3 cm、带2片半叶、下切口切为斜面的穗条,扦插成活率高于其他处理。最佳穗条应是同一枝条靠梢部1～2段,长度10 cm左右、直径0.3 cm、带2片半叶、下切口成斜面的穗条。     

半枫荷扦插育苗技术

采用正交试验设计,探讨植物生长调节剂种类、浓度、处理时间以及扦插基质、插条剪制方式与木质化程度对半枫荷Semiliquidambar cathayesis扦插生根率、根系数及苗高的影响。结果表明,插条采用200 mg·L-1 ABT1生根剂浸泡30 min后扦插于基质A(一层2 cm河沙,上覆一层2 cm黄泥土)中,生根率最高(90.3%),且插条平均根系数及苗高均最佳。影响插条上述生长指标的主次因素为基质种类＞生长调节剂种类＞生长调节剂浓度＞处理时间。不同插条处理中,以截取6 cm长半木质化嫩枝进行双削面处理的生根率最高,且根系数及苗高生长指标亦最佳。     

欧洲云杉的扦插基质选择和穗条效应研究

以欧洲云杉6年生母树为采穗母株,系统研究了不同插穗条件对生根和幼苗生长的响应,同时观测了网袋容器基质配比对扦插幼苗生长的影响.结果表明:扦插后20 d愈伤组织开始形成,37 d时根尖开始出现,50～65 d是生根的高峰期和根系发育期,65 d时扦插苗根系基本形成.不同基质对欧洲云杉插穗生根率影响达到极显著水平,1份泥炭...     

Leaf number and position effects on the survival and performance of grape microcuttings in vitro,and the sensitivity of the cut nodal region to the medium

The presence of leaf in microcuttings of grape cvs. Arka Neelamani and Thompson Seedless promoted rooting in vitro (MS, 1 μM IAA, 0.1 μM GA₃, 3% sucrose) but the effect varied depending on the number of leaves and position of the leaf on the cutting. Single node cuttings with a full-length lower internode and a lamina at top (LAT) showed earlier rooting and more root and shoot growth than cuttings with lamina positioned at the middle (LAM), while cuttings with a leaf at the base (LAB) of the cutting and full-length upper internode exhibited a lower percent rooting and sprouting, poor root and shoot growth, and low survival. Partial or complete removal of the upper internodal segment in LAB cuttings improved rooting and sprouting suggesting the possible operation of an inhibitory effect by the upper internode. Retaining an upper leaf in LAB cuttings (LAB+UL) resulted in necrosis of the upper leaf often followed by the lower one. The extent of necrotic damage was influenced by the leaf area and position or age of the cutting on the stock shoot. Retaining the lower internode in LAB and LAB+UL cuttings which held the node–leaf junction away from the medium, or reducing the concentration of MS medium helped significantly in improving the survival and performance of these cuttings. The difference in reaction between LAB and LAT cuttings was attributable mainly to the difference in the sensitivity of the stem part that came in contact with the medium. Removal of the leaf in LAB cuttings reduced this sensitivity. The majority of the LAB and LAB+UL cuttings, as well as non-rooting or delayed rooting LAT and LAM cuttings, exhibited high purple pigmentation of leaf, petiole and stem. Two-leafed cuttings in vitro showed poor survival, less rooting and low plantlet output compared to single-leafed cuttings. This revised version was published online in June 2006 with corrections to the Cover Date.     

IBA浓度、扦插时间对江西杜鹃和百合花杜鹃扦插生根的影响

为探明有鳞大花亚组杜鹃扦插生根的最佳IBA浓度和扦插时间,该研究以江西杜鹃、百合花杜鹃为材料,分别采用腐叶土+河沙(1:1)、泥炭+珍珠岩+蛭石(3:1:1)基质,开展了4个IBA浓度和4个扦插时间的生根试验.结果表明:IBA浓度对除老叶留存数外的所有指标有显著影响,其中100 mg·L-1 IBA处理生根率、新梢长最大,腐烂率最低,其它指标也表现良好,为最佳生根浓度;50 mg·L-1 IBA处理根幅、新梢率最大,但不定根数最少,效果其次;200 mg·L-1 IBA处理促进根系生长,但生根率较低、特别是显著抑制新梢发育;对照处理生根效果最差.扦插时间对所有生根指标均有显著影响,早春(04-18)木质化硬枝扦插除老叶留存数较差外,其它指标均表现极佳,为最适扦插时间;秋季(10-19)半木质-木质化过渡枝扦插效果其次;夏季(06-21)嫩枝及(08-16)半木质化枝生根效果极差,不宜进行扦插育苗.物种、基质对生根指标也有显著影响,百合花杜鹃扦插生根能力强于江西杜鹃,泥炭+珍珠岩+蛭石(3:1:1)基质生根效果优于腐叶土+河沙(1:1).该研究结果首次发现早春新梢萌发前采用木质化硬枝扦插可以显著提高两种杜鹃的生根效果,为该亚组杜鹃的扦插育苗提供了科学依据.     

小果核果茶扦插繁殖技术研究

小果核果茶为山茶科石笔木属常绿乔木,树形美观,叶泽光亮,洁白亮丽的花朵和茂密的果实具有较高的观赏价值;而且其种子含油量高,是一种具有潜在开发价值的新型生物能源植物。该研究采用4因素3水平的正交设计,分析了激素种类、处理浓度、浸泡时间和扦插基质对小果核果茶扦插生根的影响,并以生根率、生根数和平均根长为扦插生根效果的评价指标,构建生根效果指数,总体评价小果核果茶的生根效果。结果表明:对生根效果指数影响最大的是扦插基质,激素种类次之,影响最小的是处理时间。其中,扦插基质对生根效果指数的影响达到显著水平(P0.05);当激素种类为NAA、处理浓度为500mg·L~(-1)、处理时间为12 h、扦插基质为泥炭土时,小果核果茶扦插的生根效果最好。该研究结果为小果核果茶的栽培生产、育种以及资源开发和利用提供了科学依据。     

Roles of leaf in regulation of root and shoot growth from single node softwood cuttings of grape (Vitis vinifera)

The role of leaf in regulation of root and shoot growths in single node softwood cuttings of grape (Vitis vinifera) was characterised. Leafy cuttings showed early rooting, vigorous root growth and subsequent shoot development. Defoliation at planting induced early sprouting, but adversely affected rooting and decreased the survival of cuttings irrespective of pre‐planting treatment with 100 μM indole 3‐acetic acid (IAA). Treatment with IAA did not affect the percent rooting of leafy cuttings but increased root and shoot growth. Leaf weight (wt) and leaf area of the cuttings showed a highly significant correlation to root wt of the new plant at 4 wk after planting, while cutting stem + petiole wt was either not or less significantly correlated to root and shoot weights of the subsequent plant. The greater the area or wt of leaf, the better the root and shoot growths, implying that leaf contributed to adventitious root growth. However, retaining the leaf for just 2 days was enough to stimulate rooting in more than 80% of the cuttings, suggesting that leaf tissue could also induce root formation. Root growth increased with the period of leaf retention but leaf removal before 3 wk triggered sprouting leading to high mortality in rooted cuttings. Bringing the leaf closer to the rooting zone by preparing leaf at base (LAB) cuttings delayed rooting and sprouting compared with the standard leaf at top (LAT) cuttings. An inhibitory effect on rooting and sprouting by the exposed upper internode region in LAB cuttings is suggested.     

布洛芬对菊花插条生根、菊苗质量的影响

研究了布洛芬对菊花插条生根、茎叶生长和菊苗质量的影响。结果表明,将菊花插条束蘸1000mg.L^-1布洛芬液5g然后扦插,能有效地促进菊花插条生根,显著增加平均每插条的生根数、最长根长度和根干重;并能促进菊苗生长,增加茎叶鲜重;菊苗的质量明显提高。     

麻栎和闽楠幼苗叶功能性状及生物量对光照和施肥的响应

光照和养分条件是影响植物生长的重要环境因子,不同生活型植物对环境异质性的响应机制不同。以落叶阔叶树种麻栎和常绿阔叶树种闽楠幼苗为研究对象,设置2个光照梯度（全光照和45%全光照）和4个施肥梯度（不施肥、氮磷供应比为5、15和45）共8种处理,研究光照和施肥及其交互作用对麻栎和闽楠生物量和叶形态、生理及化学性状的影响,并探讨了叶功能性状和生物量的关系。结果表明：（1）光照、施肥及其交互作用对光合气体交换参数（除水分利用效率外）、叶绿素荧光参数、叶形态指标（除比叶面积外）、单位质量叶氮含量和根冠比影响显著（P<0.05）。此外,光照和施肥对地上生物量和总生物量影响显著（P<0.05）。（2）全光照显著增加了麻栎和闽楠单株总叶面积和地上、地下生物量及总生物量（P<0.05）,而遮荫降低了非光化学猝灭系数、光合氮利用率和根冠比,增加了单位质量叶氮含量。（3）在全光照处理中,施肥显著增加了麻栎和闽楠水分利用效率（P<0.05）;在遮荫处理中,氮磷供应比45显著增加了麻栎和闽楠净光合速率和水分利用效率（P<0.05）。（4）麻栎和闽楠在全光照中倾向于资源获取策略,在遮荫中偏向于资源保守策略。在光照和施肥处理中,麻栎和闽楠单株总叶面积与地上生物量均显著正相关（P<0.05）。总之,单株总叶面积是预测麻栎和闽楠幼苗地上生物量变化的稳定指标,施肥有助于增加低光环境下麻栎和闽楠幼苗的生态适应能力。     

闽楠叶片功能性状及表型可塑性对其与杉木混交的响应

慢生（闽楠）与速生（杉木）树种混交后,植物是如何改变功能性状来适应环境,在资源获取与分配权衡中来实现共存？是人工林精准提质改造过程中的关键问题,研究了闽楠（Phoebe bournei）与杉木（Cunninghamia lanceolate）混交后,其叶厚（LT）、叶面积（LA）、比叶面积（SLA）、碳含量（LC）、氮含量（LN）、磷含量（LP）和氮磷比（N：P）7项性状指标的差异,探讨其各性状间的变异大小及其相关关系。结果表明：（1）与闽楠纯林相比,混交林闽楠叶片叶面积、比叶面积、叶碳含量、叶氮含量和氮磷比分别增加了16.78%、8.50%、3.12%、21.38%和17.61%,而叶厚与叶磷含量减少了8.80%和25.87%,除叶碳含量差异不显著,其他6项功能性状差异性均达到显著（P<0.05）。（2）混交使闽楠叶LC、LN、LP含量与LT、LA、SLA相关性均发生明显的变化,对其叶厚、叶面积、比叶面积及其交互作用对叶片C：N、C：P、N：P产生一定的影响,表明混交闽楠叶功能性状间的相关关系发生了适应性调整;（3）闽楠主要叶片功能性状的表型可塑性指数分布在0.04-0.33之间,叶厚、叶面积、比叶面积和氮磷比的可塑性变化不敏感（PPI<0.20）,叶氮含量、磷含量的可塑性变化较敏感（PPI>0.20）,其大小排序为LP > LN > N：P > LA > SLA > LT > LC。以上结果表明了闽楠杉木混交造林模式对闽楠叶形态性状可塑性变化影响较小,没有受到生长空间和光资源的限制,混交是一种较好的造林模式。但闽楠叶氮、磷含量可塑性变化在混交模式中十分敏感,表明生长过程中可能会受到N、P的限制,在培育过程中应注意N肥和P肥的及时补充。这一研究结果,将为今后速生树种与珍贵树种混交造林模式研究提供理论与数据支撑。     

Effect of auxins on adventitious rooting from stem cuttings of candidate plus tree Pongamia pinnata (L.), a potential biodiesel plant

Pongamia pinnata, commercially important tree species used to produce biofuels, is known for its multipurpose benefits and its role in agro-forestry. Present study examines the amenability of vegetative propagation and effect of maturation in candidate plus tree P. pinnata through rooting of stem cuttings treated with varying concentrations and combinations of auxins. The performance of the cuttings was evaluated using SAS GLM software and the data were analyzed as a one-way classified data with and without sub sampling for inferring auxin concentration that can be included in programmes aimed at genetic improvement of the tree species. All auxin treatments promoted sprouting and at lower concentrations triggered/enhanced rooting of cuttings. The effectiveness was in the order of IBA > NAA > IAA when applied singly. IBA at 4.92 mM was found to be most effective where rooting percentage and number of roots were significantly higher (P < 0.01) than in control. However higher concentrations of auxins above 7 mM in general inhibited the rooting of cuttings. The interaction among auxins was found to be effective in root induction and differentiation and the most stimulating effects were observed in three-component mixture. The effect of other cutting characteristics such as juvenility and cutting position on rooting is also discussed.     

沙生柽柳扦插生根过程插穗相关理化特征分析

选取沙生柽柳半木质化枝条进行苗床扦插,通过实验测定插穗生根过程中内源激素(IAA、GA3、ZR、ABA)含量、可溶性营养物质(糖、蛋白质)含量及相关氧化酶(PPO、POD、SOD、IAAO)活性的动态变化特征,探讨沙生柽柳插穗扦插生根机理。结果表明:(1)沙生柽柳插穗内源激素含量随生根进程而发生变化,其中,IAA含量在扦插35d最大,并出现较大的波动变化;ZR含量在扦插55d前后变化明显,呈现低水平向高水平转化趋势;ABA、GA3含量依次呈先升高后降低再升高的变化过程,并在扦插15d和55d(80d)呈现变化的峰值和谷值。(2)沙生柽柳扦插生根与相关氧化酶活性密切相关,其中,POD、IAAO活性在插穗扦插35d后长时间保持较高水平,直至插穗生根后POD活性明显降低,IAAO活性有所增加;PPO、SOD活性则在插穗扦插15d保持较高活性,且PPO活性的变化均匀,SOD活性的高低交替变化明显。(3)在沙生柽柳扦插生根期间,插穗可溶性糖含量呈现生根前消耗减少与生根后积累增加两大变化过程,可溶性蛋白质含量表现为扦插后逐步积累增加的变化趋势。研究表明,高水平的IAA、ZR和低水平的GA3、ABA共同调控着沙生柽柳插穗生根;IAA能够通过促进插穗POD、PPO、IAAO活性变化来影响生根,较高的POD、IAAO活性可调节插穗IAA水平,高水平的PPO活性则催化插穗IAA-酚酸复合物的形成,进而诱导插穗生根。     

Detection of quantitative trait loci influencing growth trajectories of adventitious roots in Populus using functional mapping

The capacity to root from cuttings is a key factor for the mass deployment of superior genotypes in clonal forestry. We studied the genetic basis of rooting capacity by mapping quantitative trait loci (QTLs) that control growth rate and form of root traits in a full-sib family of 93 hybrids derived from an interspecific cross between two Populus species, P. deltoides and P. euramericana. The hybrid family was typed for different marker systems (including SSRs, AFLPs, RAPDs, ISSRs, and SNPs), leading to the construction of two linkage maps based on the female P. deltoides (D map) and male P. euramericana (E map) with a pseudotestcross mapping strategy. The two maps were scanned by functional mapping to detect QTLs that control early growth trajectories of two rooting traits, maximal single-root length and the total number of roots per cutting, measured at five time points in water culture. Of the six QTLs detected for these two growth traits, only one is segregating in P. deltoides with poor rooting capacity, while the other five are segregating in P. euramericana showing good rooting capacity. Tests with functional mapping suggest different developmental patterns of the genetic effects of these root QTLs in time course. Five QTLs were detected to change their effects on root growth trajectories with time, whereas one detected to affect root growth consistently in time course. Knowledge about the genetic and developmental control mechanisms of root QTLs will have important implications for the genetic improvement of vegetative propagation traits in Populus.