杨树耐盐碱品种选育研究进展

土壤的盐渍化是影响农林业生产和生态环境的严重问题,而选育耐盐碱品种是开发利用盐碱地的最有效方式。目前选育耐盐碱杨树品种主要通过常规方法、突变体筛选方法及基因工程等方法。文章对这3种方法的研究进展进行了概述,同时指出杨树耐盐碱品种选育存在的问题及今后应采取的措施。     

几个杨树新品系苗期耐盐碱试验

本文采用室外大花盆栽培的方法,对几个杨树新品系的耐盐碱性进行了初步测定。采用方差分析、多重比较、聚类分析的数学手段进行分析,初步确定了不同杨树新品种对盐碱土的适应性及适应范围。结果表明:不同杨树品系的高生长,在同一土壤类型中有显著差异,径生长只是个别品系间的差异显著。在不同土壤类型中同一品系的高生长及径生长差异显著。不同杨树品系在不同土壤类型中的成活率在生长初期变化不大,后期则随着盐碱土含量的增加,苗木生长及保存率都明显降低。当含盐量在0.255%~0.320 7%范围内时,有明显抑制作用;含盐量在0.320 7%以上时,随着时间的推移苗木逐渐死亡。同时根据综合指标确定了10个杨树品系对盐分及pH值的适宜生长范围。     

大连地区黑杨派优良无性系选择

以树高、胸径、抗病虫害指数为因子,对11个新无性系进行了早期选择(5 a)和综合选择(9 a)。结果表明:I108、I107、I-214的树高、胸径、材积遗传增益,分别比参试群体平均提高12.53%、14.30%、36.71%;遗传增益比对照(荷兰3930)分别提高34.07%、23.58%、85.21%。同时具有适应范围广、抗病虫强的特性,是大连地区杨树造林优良无性系。     

速生耐盐碱白榆抗寒性评价

以速生耐盐碱白榆58为试材,对中、上部成熟枝条进行低温处理,用相对电导率曲线配以Logistic方程,利用拐点温度估测计算组织的半致死温度,评价其抗寒温度,并通过测定水分饱和亏、榆苗恢复生长试验等指标综合评价,结果表明:该榆树品种耐寒能力在-25℃以上,抗寒能力较强。     

几种耐盐碱绿化地被植物

我国北方不少地区土质含盐碱量较高，城市绿化植物品种单一，而我国耐盐碱地被植物资源丰富，有许多还未引起人们的注意。现介绍一些适宜种植在北方盐碱地区的地被植物。     

滨海盐碱地大果沙棘适应性及耐盐碱试验

本文通过对引进的15个大果沙棘新品种在山东省滨海盐碱地的生长观测，研究大果沙棘不同品种在滨海盐碱地的适生性。为盐碱地生态经济树种选择和开发利用提供理论依据。     

杨树新无性系定植试验

引进杨树新无性系５８个,经苗期观测,选择９个新无性系营造定植试验林。通过５年观测,结果表明,这些新无性系的造林成活率、胸径、材积生长量均超过对照。初步认为中洛２号、ＮＬ－１１５０、中林４６等７个新无性系可作为杨树更新换代品种扩大繁育推广。     

不同黑杨无性系叶片及单木水平蒸腾特性研究

以廊坊地区杨树胶合板用材林主要造林树种中林46杨和廊坊杨为研究对象,应用快速称重法和热扩散茎流计分别观测了不同杨树叶片蒸腾速率和树干液流变化特征,旨在为该地区更精确地估计生态用水定额提供科学依据,而且也可为该区域杨树胶合板材林的造林、营林及流域综合管理提供理论基础。结果表明:无论晴天还是阴天,林木叶片蒸腾速率日变化都呈现有规律的单峰曲线,晴天表现为单峰宽峰曲线,阴天为单峰窄峰曲线;树干边材液流的日变化均表现出明显的昼夜规律;树干的测定方位不同,其液流速率存在着一定差异,白天均表现出一致的规律:树干南侧液流速率>树干北侧液流速率,而夜间树干南北液流速率大小相差不大,维持在0～2cm/h上下波动。     

适宜在滨海园林绿化推广的几种耐盐碱绿化树种调研

分析了滨海园林绿化现状,提出了在创建江苏省园林城市过程中,滨海应大力推广沿海耐盐绿化树种,不仅可以改变沿海绿化树种单一的格局,而且通过多个绿化树种的引进也可以提升环境美化的层次。     

Gas exchange characteristics of Populus trichocarpa, Populus deltoides and Populus trichocarpa x P. deltoides clones

Responses of net photosynthesis, dark respiration, photorespiration, transpiration, and stomatal conductance to irradiance, temperature, leaf-to-air vapor density difference (VDD), and plant water stress were examined in two Populus trichocarpa clones (one from a moist, coastal climate in western Washington and one from a dry, continental climate in eastern Washington), one P. deltoides clone, and two P. trichocarpa x P. deltoides clones. Light saturation of photosynthesis in greenhouse-grown trees occurred at about 800 micromol m(-2) s(-1) for P. deltoides, P. trichocarpa x P. deltoides, and the eastern Washington ecotype of P. trichocarpa, but at about 600 micromol m(-2) s(-1) for the western Washington ecotype of P. trichocarpa. Average net photosynthesis (at saturating irradiance and the optimum temperature of 25 degrees C) was 20.7, 18.8, 18.2 and 13.4 micromol CO(2) m(-2) s(-1) for P. deltoides, P. trichocarpa x P. deltoides, and the eastern and western Washington clones of P. trichocarpa, respectively. In all clones, net photosynthesis decreased about 14% as VDD increased from 3 to 18 g H(2)O m(-3). Stomatal conductance decreased sharply with decreasing xylem pressure potential (XPP) in all clones except the western Washington clone of P. trichocarpa. Stomata in this clone were insensitive to changes in XPP and did not control water loss. Complete stomatal closure (stomatal conductance < 0.05 cm s(-1)) occurred at about -2.0 MPa in the eastern Washington clone of P. trichocarpa and around -1.25 MPa in the P. deltoides and P. trichocarpa x P. deltoides clones. Transpiration rates were highest in the P. trichocarpa x P. deltoides clone and lowest in the western Washington clone of P. trichocarpa. The P. deltoides clone and eastern Washington clone of P. trichocarpa had the highest water use efficiency (WUE) and the western Washington clone of P. trichocarpa had the lowest WUE. The hybrids were intermediate. It was concluded that: (1) gas exchange characteristics of eastern and western Washington clones of P. trichocarpa reflected adaptation to their native environment; (2) crossing the western Washington clone of P. trichocarpa with the more drought resistant P. deltoides clone produced plants better adapted to the interior Pacific Northwest climate, although the stomatal response to soil water deficits in the hybrid was conservative compared with that of the eastern Washington clone of P. trichocarpa; and (3) introducing eastern Washington clones of black cottonwood into breeding programs is likely to yield lines with favorable growth characteristics combined with enhanced WUE and adaptation to soil water deficits.     

响对杨和意大利杨花粉处理及杂交试验

对响叶杨１７个单株、意大利杨３个无性系花粉处理及杂交试验结果表明，其花序长度、开花期、花粉生命力和花粉管长度在株间或无性系间存在显著差异，这种差异主要是由遗传控制的，也受到生长条件的影响。低温和干燥是贮藏花粉的必要条件，纯净花粉干燥后密封置０～５℃冰箱中，至少可贮藏１个多月，“１０％～１５％蔗糖＋０．７１％～１．００％琼脂＋８０×１０－６硼”的配方培养基最适于花粉的培养。室内切枝水培时增加光照和提高温度可以使意大利杨提早开花，反之则延迟开花，通过调节光、温，基本可使响叶杨与意大利杨花期相遇。意大利杨Ⅰ－６９、Ⅰ－７２与响叶杨杂交，基本上是亲和的，２２个组合获得１６个组合杂种，不同组合的杂种种子千粒重和出苗率是不同的，并且种子千粒重将会影响出苗率，响对杨株间杂交也有类似情况。     

Organic solute accumulation and dehydration tolerance in three water-stressed Populus deltoides clones

The relationship between osmotic potential, water-soluble organic solutes and electrolyte leakage was investigated in three greenhouse-grown eastern cottonwood (Populus deltoides Bartr.) clones. The Ohio Red (from southern Ohio) and Platte (from eastern Nebraska) clones were selected because they differ in dehydration tolerance, gas exchange and osmotic potential. A third clone, Wildcat (from western Nebraska) was included because of its origin in a very dry area. Plants were either watered daily (control) or watered every 4-6 days (preconditioned). A third group of plants was watered daily until it was water-stressed at the end of the experiment (nonconditioned). Leaves for osmotic potential and water-soluble solute determinations were sampled at predawn after plants were rewatered. All clones showed osmotic adjustment ranging from 0.23 to 0.48 MPa. Organic solutes contributed up to 48% of the total osmotic adjustment. The solutes that contributed at least -0.05 MPa each to leaf osmotic potential in any clone were sucrose, malic acid, glucose, fructose, myoinositol and salicin. Fructose and glucose concentrations were unchanged or declined in preconditioned Ohio Red and Platte but increased in Wildcat. The Ohio Red clone had the highest sucrose concentration in both well-watered and preconditioned plants, and a lower injury index (more membrane stability) than Wildcat in the preconditioned plants, whereas nonconditioned Platte displayed the greatest electrolyte leakage of all clones and treatments. Cell membrane stability was correlated to osmotic potential and sucrose concentration only in Ohio Red.     

胡杨种子冷藏及播种技术

通过对前人研究成果的分析,并结合多年的生产实践经验,总结了一套胡杨种子的采集、处理及储存,以及播种育苗的技术,对于维持我国荒漠地区的生态稳定具有积极作用。     

美洲黑杨无性系的苗期生长比较

从美国田纳西州、路易斯安那州引进599个无性系,通过3年苗期试验,对苗期生长表现较好的13个无性系进行生长量测定,结果表明：一根一干苗各无性系之间地径生长存在显著性差异,二根一干苗和三根一干苗各无性系之间地径生长存在着极显著性差异;苗高生长在各无性系之间均存在着极显著性差异;参试无性系的地径、苗高表型变异系数分别为12.638%和5.570%,广义遗传力分别为0.835和0.860,遗传变异系数分别为11.562%和5.150%。说明各性状遗传潜力较大,存在着广泛的遗传变异,具有获得较大遗传增益选择的潜力。     

Characterization and identification of leaf morphology of Populus deltoides Bartr.clones

Leaves are of fundamental importance to plants,representing their facility to generate power and are the sensing units of plants towards the environment.An attempt was made to characterize and compare the variations of leaf morphology of various Populus deltoides Bartr.clones by studying the winter buds and other leaf parameters of fully developed leaves.To achieve these objectives,forty-three exotic and indigenous clones of P.deltoides Bartr.were evaluated for different parameters.On the basis of various morphological characteristics the results reveal that each clone has a distinct color pattern of leaves.Different colors observed in these clones varied from light green through green to dark green.Two distinct lengths of the leaf apex were found,i.e.,short and long; as well both acuminate and acute apex types were found.Erratic distribution of serration of leaves was also found.In this study,the morphological traits of leaves provided discriminatory grounds for separating various populations of P.deltoides Bartr.clones.Winter bud studies indicate that different clones vary considerably with regard to shape,color,shape of leaf scars and exudation.     

杨树EST-SSR标记的开发

利用来自美洲黑杨及欧美杨的20 023条EST序列,进行EST-SSR标记开发研究.首先对这些EST序列进行序列拼接,然后在非重复序列中发现由二核苷酸至五核苷酸组成的SSR重复序列.共在10 816个非重复序列中发现1 604个序列含有SSR,占总非重复序列的14.8%.在发现的1 918个SSR重复序列中,二核苷酸重复是最丰富的重复类型,占总类型的62.3%.设计合成48对SSR引物,利用6个不同的杨树品种对其进行验证.结果约90%的引物获得扩增产物,58%的引物在6个不同杨树品种中产生多态性分离.另外,还对重复序列的数量及重复类型进行了讨论.     

南方常绿杨容器苗培育技术

从穗条的采集及处理、苗圃地的建立、扦插与管护等方面介绍南方常绿杨树 (Populusdeltoides× P.nigracv.Chile)容器苗的培育技术     

胡杨耐盐分子机制研究进展

胡杨耐盐机制的研究涉及植物生理、生化及分子生物学等方面。本文对胡杨耐盐分子机理方面的研究进行了综述,探究了胡杨cDNA基因文库的构建,渗透调节物质,盐离子代谢,以及膜系统稳定性等对耐盐所起的作用。阐述了胡杨耐盐研究的重要性及意义。     

山杨与美洲黑杨远缘杂交障碍克服的研究

以山杨为母本、美洲黑杨为父本,对克服山杨与美洲黑杨派间杂交障碍技术进行研究。结果表明：用正己烷有机溶剂熏柱头后再用山杨花粉提取液处理柱头能有效地克服山杨与美洲黑杨之间的杂交障碍。同时,用形态学标记对杂交子代及其亲本进行鉴定分析,杂种子代主要偏向于父本型与母本型,从而证明杂种子代是其真正的杂种。