转TaLEA基因小黑杨无性系苗期生长性状Logistic模型构建

以10个转TaLEA小黑杨无性系和1个对照无性系为材料,对无性系苗期苗高和地径生长过程进行测定并构建Logistic模型,探讨不同无性系苗期生长过程的变异情况。结果表明:转基因小黑杨无性系苗高和地径生长过程高度符合"S"型曲线,所有Logistic模型拟合系数超过0.9,表明拟合效果显著。方差分析结果表明不同无性系苗高和地径间差异均达到极显著水平(P0.01)。参试无性系苗高平均速生期持续期为48天,速生期内平均生长量为1.85 cm,地径平均速生期持续时间为70天,速生期内平均生长量为0.09 mm。苗高、地径均与速生期内生长量、速生期内平均日生长量间呈极显著正相关。转基因无性系XL-1和XL-9苗期生长较快,苗高(地径)分别比对照高16.37%(32.82%)和10.92%(22.68%),表明转LEA基因对无性系生长具有一定的影响。此研究为小黑杨苗期管理提供理论依据。     

肯氏南洋杉实生苗培育技术及苗木质量分级

选择生长健壮的30～60年生成年肯氏南洋杉Araucaria cunninghamii母树进行采种,播种前种子去皮处理,幼苗期加强水肥管理和病虫害防治以提高实生苗苗木质量。以根长、地径和苗高为肯氏南洋杉1、2年生实生苗分级的质量指标,应用快速聚类法K-Means分别进行聚类分析,将苗木分为3级。1年生实生苗苗高(≤12 cm)、地径(≤2.5 cm)过小,不适合出圃造林; 2年生实生苗中的Ⅰ级苗和Ⅱ级苗根长、地径、苗高指标均符合出圃造林标准,可以出圃; 2年生实生苗中Ⅲ级苗地径、苗高依然未达到出圃标准,不建议出圃。     

中国马褂木不同种源苗期生长规律研究

对中国马褂木6个种源(云南金平、浙江安吉、福建武夷山、贵州黎平、广西全州、江西庐山)一年生实生苗的苗高生长规律进行研究。结果表明:(1)各种源在苗高生长上存在着极显著的差异。(2)利用logistic曲线拟合其苗高生长方程,发现各种源苗高生长均呈现明显的"慢—快—慢"的"S"型生长节律。(3)利用有序样本聚类分析将苗木生长划分为幼苗期、生长前期、速生期、生长后期4个阶段,福建武夷山种源最早进入速生期,且持续时间最长,江西庐山种源最晚进入速生期,且持续时间最短。速生期苗高净生长量占总生长量最大的是浙江安吉种源,达56.05%;第二是福建武夷山;最小的是江西庐山种源,只有34.29%。(4)依据苗高和地径两个性状的聚类分析把6个种源分成三大类,第一类是全州种源,苗高生长表现最好;第二类是金平、安吉、武夷山、黎平种源;第三类是庐山种源。     

不同产地苦楝苗期生长节律研究

苦楝在我国分布广泛,具有丰富的遗传变异性。为进一步做好苦楝种源筛选和良种选育工作,该文对不同产地苦楝实生苗生长性状和各阶段的生长特点进行了比较分析,初步揭示了苦楝苗期生长规律。以15个产地的1年生实生苗为试材,对苗高、地径、复叶生长及生物量积累等生长性状进行了观测分析,并用Logistics方程对生长节律进行了拟合。结果表明:(1)不同产地苦楝苗高、地径生长差异均达显著水平,根生物量、茎生物量及复叶相关性状差异均达极显著性水平;(2)苗高和地径生长均呈现慢-快-慢的S型生长规律,且均存在2次生长高峰,与苗高生长高峰出现时间相比,地径生长高峰出现时间较晚;(3)Logistic拟合方程的R²为0.976～0.994,均达到极显著相关水平,说明可用Logistic方程拟合苦楝的生长节律;(4)总体上地径速生期较苗高速生期长20～30 d,北方产地苗高和地径进入速生期和结束速生期的时间均早于南方产地,速生期苗高和地径累积生长量均超过总生长量的60%;(5)各生长指标均与纬度负相关,苗高、生物量及复叶面积与经度正相关,其他指标与经度负相关。综上结果表明,苦楝为全期生长型树种,各生长性状在产地间达显著差异水平,生长受纬度和经度双重控制,以纬度控制为主。     

不同种源/家系山鸡椒苗期生长性状遗传变异

为筛选苗期表现优良的山鸡椒[Litsea cubeba(Lour.)Pers.]种源/家系,对其13个种源55个家系的苗高(h)、地径(bd)性状进行遗传变异分析。结果表明,山鸡椒1年生苗木生长期可分为生长初期、速生期和完全木质化期,苗高、地径生长不同步。山鸡椒不同种源、家系间的苗高、地径生长量均存在极显著差异(P0.01)。利用综合选择指数法建立综合选择式为I=0.007Xh+0.74Xbd,建阳2号、富阳1号、遂昌8号、遂昌13号和岳西1号等5个家系优良度为I级,入选率为9.1%。浙江富阳和福建建阳2个种源的苗高、胸径期望遗传增益值最高;建阳2号、遂昌8号、富阳1号、遂昌13号、岳西1号、建阳3号、岳西6号等7个家系的苗高、胸径期望遗传增益最高。因此,依据生长性状综合选择和遗传增益表现,选择出建阳2号、富阳1号、遂昌8号,遂昌13号,岳西1号5个家系以及浙江富阳和福建建阳2个种源为优良家系/种源。     

Growth pattern of Liriodendron chinense seedlings from different provenances

对中国马褂木6个种源(云南金平、浙江安吉、福建武夷山、贵州黎平、广西全州、江西庐山)一年生实生苗的苗高生长规律进行研究.结果表明:(1)各种源在苗高生长上存在着极显著的差异.(2)利用logistic曲线拟合其苗高生长方程,发现各种源苗高生长均呈现明显的“慢—快—慢”的“S”型生长节律.(3)利用有序样本聚类分析将苗木生长划分为幼苗期、生长前期、速生期、生长后期4个阶段,福建武夷山种源最早进入速生期,且持续时间最长,江西庐山种源最晚进入速生期,且持续时间最短.速生期苗高净生长量占总生长量最大的是浙江安吉种源,达56.05％;第二是福建武夷山;最小的是江西庐山种源,只有34.29％.(4)依据苗高和地径两个性状的聚类分析把6个种源分成三大类,第一类是全州种源,苗高生长表现最好;第二类是金平、安吉、武夷山、黎平种源;第三类是庐山种源.     

指数施肥对白桦裸根苗生长动态、生物量分配及光合作用的影响

设定常规施肥(CF)、指数施肥(EF)和1.5倍指数施肥(EF1.5)3种施肥处理研究不同氮素施入方法和剂量对白桦1年生裸根苗生长(苗高、地径、生物量)动态、生物量分配、相对生长速率(RGR)和光合作用的影响。研究结果表明:(1)3种处理苗木生长前期苗高、地径和生物量均无显著差异,生长后期EF与EF1.5显著高于CF(P<0.05),EF与EF1.5间差异不显著(P>0.05);(2)生长结束时,EF、EF1.5处理苗高分别比CF高18.2%和25%(P>0.05),地径分别比CF高11.2%和5.8%(P<0.05),单株生物量分别比CF高41.5%和25.4%(P<0.05);(3)EF与EF1.5处理苗木的茎、叶、根生物量均显著高于CF,各处理间苗木的根冠比差异不显著(P>0.05);(4)EF1.5处理和EF处理苗木苗高、地径及生物量相对生长速率(RGR)均显著高于CF处理(P<0.05),而EF1.5处理和EF处理间仅生物量相对生长速率达到显著水平,且EF>EF1.5(P<0.05);(5)苗木生长高峰期,EF处理提高了苗木叶片的光合能力。EF处理苗木叶面积高于CF处理16.8%(P<0.05),叶绿素含量及光合速率较CF处理分别提高了4.5%(P>0.05)、5.0%(P>0.05)。EF、EF1.5处理常规施肥处理促进了苗木生长和生物量积累,二者促进效果类似,认为EF为最佳的施肥处理。     

濒危植物秦岭冷杉补光育苗技术研究

秦岭冷杉种子生活力差、成苗率低(2.2%)是制约种群恢复的薄弱环节。通过对播种后苗期2年连续补光处理,幼苗表现出良好的生长效应,苗高10.5 cm(对照为7.3 cm),地径4.5 mm(对照为2.7 mm),保存率88.6%(对照66.4%),延长了幼苗生长期,增加了苗木生物量积累,加快了苗木培育进程。     

四川桤木7×7完全双列杂交种实、种苗性状的遗传效应分析

通过对四川桤木杂交子代果实、种子及种苗性状的分析,估算四川桤木亲本的遗传参数,为四川桤木杂交育种亲本选配提供理论依据。以7个优树作为杂交亲本,按7×7完全双列交配设计进行控制授粉,测定49个杂交组合的果实、种子及苗木性状。结果表明,49个杂交组合间的果实鲜重、种子千粒重、果长、种长等表型性状及苗高、地径均存在着极显著的差异(P0.001);果实鲜重、种子千粒重、果长、种长等表型性状的一般配合力(GCA)、特殊配合力(SCA)和反交效应差异(REC)也存在着极显著的差异(P0.001)。苗高和地径的GCA、SCA和REC也存在着极显著差异(P0.001)。苗高和地径的广义遗传力分别为37.06%和38.04%,狭义遗传力分别为17.47%和16.03%,表明在苗期阶段,苗木生长受环境效应的影响较大。种实性状的加性方差是非加性方差的1.34~11.79倍,主要受加性基因效应控制,非加性效应次之。而苗高和地径的非加性方差分别是加性方差的1.12和1.37倍,主要受非加性基因效应影响,加性效应次之。综合分析杂交子代GCA、SCA和REC效应值,确定JG6和JT4为优良亲本,从49个杂交组合中初选出4个组合(BZ6×JG6、BZ6×SW2、JT4×TT13和BZ6×QJ1)为优良杂交组合,其杂交子代苗高和地径分别实现20.47%~76.22%和5.07%~43.18%的遗传增益。     

蘑菇渣堆肥对华北落叶松移植容器苗生长和营养积累的影响

为缓解草炭大量使用带来的环境问题,在华北落叶松容器育苗过程中添加蘑菇渣堆肥以替代草炭,添加蘑菇渣堆肥体积比例分别为0%(T₀)、15%(T₁)、18.75%(T₂)、25%(T₃)、37.50%(T₄)、50%(T₅)、56.25%(T₆)、60%(T₇),研究不同配比下基质的理化性质以及对华北落叶松1年生移植容器苗生长和营养积累的影响.结果表明: 当蘑菇渣堆肥替代草炭的比例≤50%时,苗木苗高、地径和生物量与常用草炭处理无显著差异,且处理T₂、T₄、T₅苗木体内养分浓度显著高于对照,基质pH值处于微酸性或中性范围,适宜苗木生长;当蘑菇渣添加比例＞50%时,基质pH值偏碱性,苗木生长受到不利影响,苗木质量下降.当蘑菇渣添加比例为15%时,苗木质量最好,苗高、地径和单株生物量达到最大.因此,蘑菇渣替代草炭培育华北落叶松移植容器苗是完全可行的,替代比例最高可达到50%,当添加比例为15%时,可培育出高质量的苗木.     

濒危树种钟萼木苗木年生长节律与适应性调查

对钟萼木Bretschneidera sinensis实播育苗、苗木物候期生长及不同试验点与不同培育方式的苗木生长进行研究。结果表明,该树种种子经催芽后发芽率达90%以上,苗木高与地径生长期主要在4～10月,10月后进入木质化状态,生长期较短是影响生长量的重要原因;高温与强光照对苗木顶芽与幼嫩叶产生灼伤影响,高温季节需进行遮荫;在高温高湿季节,易遭受病虫害为害,需加强病虫害防治。不同育苗方法表明,该树种大田裸根苗培育比容器苗更有利于苗木生长;不同生长类型的生长情况表明,良好的遗传个体在苗期表现良好的生长潜能。     

温度和土壤含水量对青冈栎种子萌发的影响

运用直播法,研究应用人工气候箱控制温度和土壤含水量对野生青冈栎种子萌发和幼苗生长的影响。结果表明:在12h光照条件下,青冈栎种子在变温为10℃/15℃时,萌发率很低,仅为(12±12.29)%;变温为30℃/35℃时,萌发率达最大,为(81±13.7)%。土壤含水量为30%～40%时,萌发率为(79±15.9)%;土壤含水量为90%～100%时,萌发率为(56.67±19.36)%。青冈栎种子萌发呈现出迅速萌发和推迟萌发的特点;温度对青冈栎幼苗的苗高、叶长和叶宽影响显著,对幼苗的地径、叶片数量影响不显著。恒温下,不同梯度土壤含水量处理对幼苗的苗高、地径、叶长、宽影响不显著。     

Restoring Caribbean Dry Forests: Evaluation of Tree Propagation Techniques

Survival and height growth of tree seedlings and rooted cuttings introduced into artificially shaded and unshaded plots in a degraded dry forest were measured at intervals for nine months. Ten tree species were selected to represent a range of ecological characteristics of the dry–forest plant community on St. John, U.S. Virgin Islands. Of three propagule types – seeds, seedlings, and rooted cuttings – introduced to field plots, seedlings survived best (52%) over the initial nine-month period. Cuttings of six species rooted successfully in a shadehouse, but only two of these species survived the nine–month field experiment. Seed germination was low, under 11% for eight of ten species tested, and four species did not germinate. Subsequent mortality of seedling recruits was moderately high. Plumeria alba was the only species for which seedling height growth was not significantly greater than cutting height growth. Shading treatment (25% of full sun) significantly increased seedling survivorship (p= 0.03) but suppressed growth slightly for some species. Shading enhanced survival of seedlings produced from broadcast seeds, but not seed germination. Mortality occurred during dry periods, apparently from drought stress. Results suggest (1) that seedling introductions are the preferred propagule type (over seeding or rooted cuttings) for ecological restoration of degraded tropical dry forests, and (2) that some level of shading is required to increase the survivorship of many dry-forest species or to avert complete mortality of some species. This study suggests that early secondary dry forest may be best restored by underplanting within the existing vegetation. Sufficient shading suitable for growth of native dry-forest trees may be attained using a nurse crop of fast-growing leguminous trees.     

Seed germination and seedling growth of two Pseudobombax species (Malvaceae) with contrasting habitats from Brazilian Cerrado

Pseudobombax tomentosum and P. longiflorum are common trees in the Cerrado region, but the former species is more common in forest edges while the later is present in open cerrado areas. This work aimed to investigate differences in seed germination and seedling growth in these species, from seed collected from Cerrado areas in Central Brazil. For this, a seed germination experiment was designed and included four replicates with 25 seeds per species; seeds were randomly distributed in the germination chamber. To evaluate initial seedling growth, seedlings height was measured up to 67 days after seedling emergence; besides, some of these seedlings were grown for biomass evaluation during nine months. Results showed that seeds of the two species had the same germinability (near 100%) and mean germination time (ca. 12 days). However, P. longiflorum showed a more spread seed germination through time, with higher values of coefficient of variation in germination time and uncertainty index; and lower values of synchronization than P. tomentosum. The two species showed basically the same growth pattern, but lower values for height of apical meristem, diameter of underground structures (mostly roots), dry mass of shoots, underground structure and total mass of seedlings in P. tomentosum were obtained, compared to P. longiflorum. Both species allocated more dry mass to underground structures in detriment of shoot. This probably allows resprouting behavior which prevents hydric stress and detrimental fire action typical of the open Cerrado areas.     

杉木和木荷种子萌发及幼苗生长对光梯度的响应

光是影响种子萌发和幼苗生长的关键因素.为理解不同树种种子萌发及幼苗生长对光梯度变化的响应机制,本文研究了不同光照强度(分别为自然光强的100%、60%、40%、15%和5%)对杉木和木荷种子萌发及幼苗生长的影响,探讨了两树种种子萌发和幼苗生长对光照响应的差异性.结果表明: 光照强度对两树种的种子萌发和幼苗生长均具有显著影响. 随着光照强度的减弱, 杉木种子萌发率增大,萌发指数增大,木荷种子萌发率和萌发指数则先增大后减小,在40%光照强度下达到最大值.两树种幼苗存活率在全光照(100%光照)下均为0,在5%～60%光照处理下则随着光照强度的减弱而显著降低.两树种幼苗根长、地径和株高对光梯度变化的响应趋势一致,随着光照强度的减弱,根长显著减小,地径和株高则先增大后减小,在5%光照强度下达到最小.随着光照强度的减弱,杉木幼苗根、茎、叶及总生物量降低,木荷幼苗生物量积累在15%～60%光照强度下较高, 5%光照强度下最小,且相同光照强度下,木荷幼苗各部分生物量均大于杉木.两树种幼苗应对低光环境时,表现出较大的茎和叶的生物量分配比,而根生物量比和根冠比降低.表明杉木苗期生长不耐阴,需要相对较强的光照,而木荷苗期具有较强的耐阴性,对弱光环境的适应性更强,能够在郁闭的林冠下定植和正常生长.     

水杉原生种群核心种质资源的繁殖特性

水杉(Metasequoia glyptostroboides)原生种群天然更新困难, 为探究其原因是否与繁殖特性有关, 本文以其核心种质资源(40株个体)为对象, 通过对生境、母树个体和种子性状的调查, 并结合田间播种试验, 分析其繁殖特性。以方差分析检测不同母树个体间种子性状、发芽率和幼苗生长特征的差异; 采用相关性分析和多元线性回归模型分析个体性状对其种子、发芽率及幼苗生长的影响; 通过Logistic模型拟合, 分析幼苗生长的节律参数。结果显示: (1) 40株母树个体仅有7株产种, 产种率仅为17.50%, 且不同母树个体间产种量差异显著(P < 0.05)。(2)不同母树个体间的种子千粒重、种子发芽率、幼苗存活率和基径生长量均存在显著差异(P < 0.05)。(3) 7株母树个体种子的平均发芽率为19.73%, 幼苗平均存活率为73.42%, 不同母树之间差异显著(P < 0.05)。(4)母树个体的胸径与种子千粒重、种子发芽率呈显著负相关(P < 0.05), 种子发芽率与幼苗存活率呈极显著正相关(P < 0.001), 树高与幼苗存活率呈显著正相关(P < 0.05)、与幼苗基径呈极显著正相关(P < 0.001)。(5)母树树高对幼苗存活率有显著正效应(P < 0.05), 胸径对种子发芽率有显著负效应(P < 0.05)。(6)苗高、基径的生长符合“S”型生长曲线(R ² ≥ 0.928)。水杉原生种群产种量低, 种子发芽率低、幼苗存活率较低, 且不同母树之间差异显著可能是造成其天然更新困难的原因。     

60Co-γ辐照对越南油茶种子发芽及幼苗形态指标的影响

为了研究⁶⁰Co-γ辐照对越南油茶Camellia drupifera种子发芽和表观形态指标的影响,选取越南油茶璠龙3号‘Fanglong 3’和璠龙5号‘Fanglong 5’种子分别进行0、40 Gy、50 Gy、60 Gy、70 Gy ⁶⁰Co-γ辐照并测定种子发芽率和出苗率以及幼苗生长表观形态指标(苗高、地径、叶长、叶宽、叶面积)。结果表明,⁶⁰Co-γ辐照对越南油茶种子发芽率影响小,对其出苗率、苗高、地径以及叶片生长有明显抑制作用,尤其是高剂量(60 Gy、70 Gy)辐照对越南油茶种子损伤较大,严重影响其出苗及幼苗生长。高剂量辐照明显延迟越南油茶的出苗时间,抑制幼苗生长,导致苗木瘦弱、生长缓慢,植株呈现矮化现象。高剂量亦抑制越南油茶叶片生长,导致叶片瘦小,生长缓慢。璠龙3号种子⁶⁰Co-γ辐照半致死剂量为64 Gy,璠龙5号为57 Gy。     

遮荫对峦大杉1年生苗木生长的影响及动态优化

以当年播种的峦大杉(Cunninghamia konishii)幼苗为材料,采用单因素试验设计3个遮荫处理(50%、75%、100%光照),每隔7 d监测地径、苗高等生长进程;应用Logistic方程拟合苗高、地径生长过程并分析其生长节律。结果表明,遮荫显著促进峦大杉幼苗全生长季的苗高、地径生长,以50%光照表现最好;不同生长阶段遮荫对峦大杉苗高、地径生长量的影响有所不同,进行动态优化十分必要。Logistic方程能较好地拟合峦大杉苗木生长动态。50%光照处理显著提高峦大杉苗高、地径的线性生长速率、最大线性生长速率和线性生长量,显著提前苗高线性生长终期、缩短线性生长持续时间,显著推迟地径线性生长始期。峦大杉苗期光照强度动态优化方案：在t≤133 d前阶段宜采用50%光照,在t＞133 d期间宜采用100%光照。     

Conditions for seedling establishment and probable function of seed in the clonal sedge Carex rugulosa Kük. in riverside marshes

Carex rugulosa Kük. forms large meadows in moist zones along estuarine riversides. These meadows are usually maintained by rhizomatous ramet production (clonal growth), and the appearance of seedlings is uncommon. We studied the conditions required for seedling establishment. In areas in which clonal ramets were dense (906–1050/m²), and the relative light intensity at ground level was low (0.8–3.8%), seed germination was entirely suppressed. In contrast, many seedlings (288–513/m²) were observed in areas in which clonal ramets had been considerably reduced (13–269/m²) by continuous inundation in the previous year. In these areas, the relative light intensity had increased (20.5–79.3%). It was inferred that seeds resisted the prolonged inundation that killed the ramets, and that germination was induced under these open conditions. These results suggest that the main functions of sexual reproduction in C. rugulosa are recovery after severe damage to vegetation using seeds from the seed bank and the dispersal of seeds to areas without dense vegetation. Most seedlings died when the marshy meadow was temporarily inundated by heavy rain. However, transplanted seedlings survived better at artificially elevated sites that were not submerged. This shows that inundation during the seedling stage impedes seedling survival. Therefore, seeds can contribute to recovery after ramet decline or colonization to open area when (i) the rainfall is not heavy to cause seedling submergence or (ii) seeds are dispersed to higher area which is not inundated.