杨树红心病危害的调查研究

杨树红心病是分布广泛、危害严重的一种病害,几乎所有杨树品种都会遭侵染,成年树病株率达100%,变色比率15.65%~50.70%。从当年生扦插苗到成年树均能发生,红心病主要发生在主干的髓心和木质部。该病的严重程度与栽植的立地条件有关,在低洼湿地栽植的杨树其变色程度严重,且随树龄的增加而加剧,生长速度快的杨树,危害程度大。杨树品种不同,危害程度不同,品种之间存在着显著差异。     

杨树烂皮病对湖北地区杨树的危害风险

杨树烂皮病是湖北地区近年来危害性上升迅速的林业有害生物,其主要寄主在湖北种植广泛。其病原金黄壳囊孢菌Cytospora chrysosperm侵染杨树枝干部,从而导致死亡。依据林业有害生物风险分析指标体系,采用多指标综合评价法对杨树烂皮病危险性进行定量化分析和评判。结果表明,杨树烂皮病在湖北省的危害风险值为2.01,即:杨树烂皮病在湖北地区为中度危险性的林业有害生物。此结果将为我省应杨树烂皮病的综合防控技术研究提供基础科学依据。     

银中杨地膜扦插育苗技术探讨

从4个方面介绍了银中杨地膜扦插育苗技术.从中得出结论:应用地膜覆盖扦插育苗具有增温、保墒、减少杂草和速生增产的作用,而且地膜育苗方法简便易行,经济效益显著,是半干旱地区发展育苗业首选技术之一.     

引起杨树湿心材的一种病原真菌--Fusarium proliferatum (Matsushima) Nirenberg

在我国,杨树湿心材是一种分布广危害严重的病害。１９９５～１９９６年从湖北、山东、河北、辽宁等省及北京地区的２０多种杨树的根、干部取样,分离到一种真菌,此菌在杨树的根、干部都有广泛的分布,依据其形态特征和培养形状,据Ｎｅｌｓｏｎ,Ｔ．Ｍ．（１９８３）《ＦｕｓａｒｉｕｍＳｐｅｃｉｅｓ》,此菌被鉴定为Ｆｕｓａｒｉｕｍｐｒｏｌｉｆｅｒａｔｕｍ（Ｍａｔｓｕｓｈｉｍａ）Ｎｉｒｅｎｂｅｒｇ。室内和田间的多次接种结果表明,Ｆ．ｐｒｏｌｉｆｅｒａｔｕｍ致病力强,能产生典型的湿心材症状,是引起我国杨树湿心材的主要病原之一,这在国内外还是首次报道。电镜观察表明,此菌能破坏杨树导管—射线间纹孔膜,与国内外有关纹孔膜的报道一致。本文还讨论了细菌及生理因素在湿心材形成过程中的可能作用。     

不同径阶杨树杨扇舟蛾防治指标研究

经过对速生丰产林4-22cm径阶杨树蓄叶量、叶面积、杨扇舟蛾食叶量、人工模拟摘叶对杨树生长量的影响等因子的调查分析，得出胸径D与杨树单株叶面积S之间的回归关系式为S=1．491D^1.2681(相关系数r=0．975)，失叶强度与杨树材积年增长量的回归模型为V=0．0038—0．0028x-0．0004x^2(相关系数r=0．9865)，确定杨树的经济允许受害水平为失叶40％，杨树失叶强度的经济阈值为0．184，根据D、S的关系式，得出杨扇舟蛾幼虫理论防治指标E与胸径D的关系式为E九=28．5104D^1．2681，E阈=17．4864D^1．2681，根据E、D关系式，计算出不同径阶杨树杨扇舟蛾幼虫虫口密度的防治指标，结合各径阶杨树树冠投影中杨扇舟蛾幼虫折算系数及生命表推算出杨扇舟蛾1～4代幼虫达到防治指标时所对应的单位树冠投影中越冬蛹的防治指标。     

Establishment strategies for poplars,including mulch and plant types,on agricultural land in Sweden

Biomass from forestry is one of the largest components of Sweden’s renewable resources. Poplars are currently the highest producing tree species available and are therefore natural choices for biomass-oriented production. Growing poplars has been of most interest on agricultural land, but the knowledge and experience about their cultivation is still limited. Factors that have a large impact on the regeneration results are plant material, competing vegetation, browsing and damage caused by voles or climatic factors. Due to large establishment costs, there is a need to find methods to secure the establishment both biologically and economically. In this study the effect of plastic mulch in combination with three different plant types (short cuttings, long cuttings and rooted plants) were tested at three different sites. Five years after planting, the overall effect of mulch was an improved plant survival and growth. In most cases, long cuttings outperformed short cuttings and rooted plants. Clonal differences were present, indicating the importance of using plant material adapted to site conditions. All sites were heavily affected by browsing and during the experimental period 100% of the plants were damaged at some point. Planting poplars without fencing is therefore doubtful. Results from this study conclude that poplars can be established with success on agricultural land if proper measures are used depending on the site to be planted.     

转蜘蛛杀虫肽与Bt毒蛋白C肽基因小黑杨对分月扇舟蛾中肠组织结构的影响

采用透射电镜观察,取食转蜘蛛杀虫肽与B t毒蛋白C肽融合蛋白基因小黑杨叶片后的分月扇舟蛾幼虫的中肠组织病理变化,结果发现：幼虫中肠组织受到严重破坏,柱状细胞、杯状细胞结构发生明显的病理变化;随着取食时间和取食量的增加,其病变和破坏的程度逐渐加剧。     

Assessment of rhizospheric microorganisms of transgenic Populus tomentosa with cowpea trypsin inhibitor ( CpTI ) gene

To have a preliminary insight into biosafety of genetically transformed hybrid triploid poplars (Populus tomentosa × P. bolleana) × P. tomentosa with the cowpea trypsin inhibitor (CpTI) gene, two layers of rhizospheric soil (from 0 to 20 cm deep and from 20 to 40 cm deep, respectively) were collected for microorganism culture, counting assay and PCR analysis to assess the potential impact of transgenic poplars on non-target microorganism population and transgene dispersal. When the same soil layer of suspension stock solution was diluted at both 1:1 000 and 1:10 000 rates, there were no significant differences in bacterium colony numbers between the inoculation plates of both transgenic and non-transgenic poplars. The uniform results were revealed for both soil layer suspension solutions of identical poplars at both dilution rates except for non-transgenic poplars at 1:10000 dilution rates from the same type of soil. No significant variation in morphology of both Gram-positive and Gram-negative bacteria was observed under the microscope. The potential transgene dispersal from root exudates or fallen leaves to non-target microbes was repudiated by PCR analysis, in which no CpTI gene specific DNA band was amplified for 15 sites of transgenic rhizospheric soil samples. It can be concluded that transgenic poplar with the CpTI gene has no severe impact on rhizospheric microorganisms and is tentatively safe to surrounding soil micro-ecosystem. [Supported by the National Project in Transgenic Plant and Application (Grant No. J2002-2003)]     

Growth and root sucker ability of field-grown transgenic poplars overexpressing xyloglucanase

Xyloglucan is thought to be a key hemicellulose cross-linking adjacent cellulose microfibrils in plant cell walls. The growth traits of transgenic poplars (Populus alba) with decreased xyloglucan from overexpression of Aspergillus aculeatus xyloglucanase were characterized during a 4-year field trial. The field-trial site consisted of two blocks, a fertile soil block and a non-fertile soil block, determined by soil analysis. In the fertile block, the growth of aboveground biomass of the transgenic poplars was reduced to 24?C44?% compared to that of wild-type poplars, in contrast to the growth seen in chamber and greenhouse conditions. In the non-fertile block, the aboveground biomass of transgenic poplars was also smaller than that of the wild-type poplars. Because poplars reproduce asexually by root suckers, we also compared the formation of root suckers from transgenic and wild-type poplars. Root suckers formed less frequently from transgenic poplars than from wild-type poplars. The growth rates of root suckers from transgenic poplars were also slower than those from wild-type poplars. The results showed that constitutive degradation of xyloglucan impairs poplar growth and vegetative reproduction ability.     

Resistenzprüfung an Pappeln aus Gewebekultur

Resistence tests on poplars raised by tissue culture. The possibility of testing poplar clones for susceptibility to poplar canker at an early stage was tested by inoculating plants, produced by tissue culture, at 1.5, 2, 4 and 6 weeks and 7 months. Results were positive and compared well with standard tests.     

Assessment of Rhizospheric Microorganisms of Transgenic Populus tomentosa with Cowpea Trypsin Inhibitor (CpTI) Gene

To have a preliminary insight into biosafety of genetically transformed hybrid triploid poplars (Populus tomentosa × P. bolleana) × P. tomentosa with the cowpea trypsin inhibitor (CpTI) gene, two layers of rhizospheric soil (from 0 to 20 cm deep and from 20 to 40 cm deep, respectively) were collected for microorganism culture, counting assay and PCR analysis to assess the poten-tial impact of transgenic poplars on non-target microorganism population and transgene dispersal. When the same soil layer of suspension stock solution was diluted at both 1:1 000 and 1:10 000 rates, there were no significant differences in bacterium colony numbers between the inoculation plates of both transgenic and non-transgenic poplars. The uniform results were revealed for both soil layer suspension solutions of identical poplars at both dilution rates except for non-transgenic poplars at 1:10 000 dilution rates from the same type of soil. No significant variation in morphology of both Gram-positive and Gram-negative bacteria was observed under the microscope. The potential transgene dispersal from root exudates or fallen leaves to non-target microbes was repudiated by PCR analysis, in which no CpTI gene specific DNA band was amplified for 15 sites of transgenic rhizospheric soil samples. It can be concluded that transgenic poplar with the CpTI gene has no severe impact on rhizospheric microorganisms and is tentatively safe to surrounding soil micro-ecosystem.     

杨干象发生量测报技术探讨

根据近年搜集到的关于杨干象CryptorrhynchuslapathiLinnaeus在不同林龄杨树上受害株率的数据 ,采取两种不同数学方法建立杨干象危害的动态数学模型。第一种是多项回归方法 ,根据时间、受害率在坐标平面上变化趋势拟合二次抛物线。预测的被害率拟合值符合精度 ,每个时点(林龄 )上被害率区间估计为Y± 0 4 0。第二种方法是灰色GM (1,1)预测模型。对于受随机因素干忧的杨干象在不同林龄的杨树上的危害情况 ,表示为时间序列的形式 ,直接利用受害株率本身去预测序列中各时点处的值 ,此模型对不很长序列能作出较准确的预测而多项回归在拟合较长序列的反映趋势上胜于后者。     

杨潜姬蜂生物学特性初步研究

杨潜姬蜂ＣｅｌａｔａｐｏｐｕｌｕｓＷａｎｇ是杨潜叶蜂幼虫的重要寄生天敌。该蜂１年１代，以老熟幼虫越夏越冬（在寄主土茧内）。４月中旬寄主幼虫危害盛期为成虫羽化产卵盛期，寄主幼虫入土后，该蜂卵始孵化直至老熟。寄生率最高可达９０％以上。     

Disease biology and histopathology of bronze leaf disease: a threat to cultivated aspens,white poplars and their hybrids

Bronze leaf disease (BLD) of species and hybrids of aspens, grey and white poplars (Genus Populus, section Populus) is a systemic disease incited by the fungus Apioplagiostoma populi (E.K. Cash & A.M. Waterman) M.E. Barr that results in a characteristic bronze to dark brown pigmentation of infected leaves in late summer and early fall. Branches on affected trees die over a period of several years, disfiguring trees and eventually leading to mortality of susceptible trees planted in landscapes. In this study, we describe the histopathology of the disease and fungus development relative to external symptoms on affected trees. A. populi hyphae were observed in leaf vessels, lateral veins and xylem vessels of stems and roots of affected trees. Hyphae were also observed in veins and vessels of asymptomatic leaves. Xylem vessels of growth rings on dead branches were completely occluded with A. populi near the vascular cambium and together with the ray parenchyma were stained a bronze colour. Evidence of putative toxin damage to mesophyll cells, not colonized by hyphae, was observed and may contribute to the characteristic tissue staining observed. The development of the fungus was consistent with previous reports, but in this study, we report additional details including perithecial development and ascospore release from predominantly abaxial leaf surfaces. We also report for the first time the isolation and growth of the pathogen in pure culture and systemic infection of roots.     

德阳市杨树云斑天牛发生情况及防治措施

自1999年至2003年连续5d对德阳地区杨树云斑天牛的发生、危害情况进行了监测、研究。弄清了云斑天牛的分布范围及特点，总结出了云斑天牛的生活规律、习性及对杨树的危害特性，并提出了针对性的防治措施。     

Leaf eating insect damage on different poplar clones and sites

As much for the geneticist as for the planter, information on sites, clones, and other factors would be decisive to reduce insect damage on poplars. In this perspective, a study was done in eight field trials in Belgium and in Luxembourg, considering two types of leaf damage on 24 clones from Italy, Belgium and the Netherlands. Damage varied considerably, depending on the clones, sites, species and parental individuals. Clone’s ranks concord on the different sites; site’s ranks are similar for the various clones. Clones with same parents have similar levels of resistance. The two types of damage are not correlated. Hybrids of P. deltoides × nigra show widespread variability; those with genetic material of P. trichocarpa are generally more resistant to caterpillar-like damage. The maximal differences are about 1 to 5 for the clones, and 1 to 10 for the sites. But the most vulnerable clone on the most favourable site was damaged almost 70 times more often than the opposite combination.     

中国杨树分子遗传改良的研究现状

杨树是中国广泛栽培的重要造林树种之一 ,我国是世界上杨树资源丰富的国家 .杨树具有速生丰产、实用性强、无性繁殖能力强 ,且基因组较小等特点 ,现已成为研究林木生理和基因工程研究的模式树种 .该文概述了基因工程技术、遗传图谱构建、重要性状基因定位以及分子标记辅助选择育种等方面在中国杨树遗传改良中的应用研究进展 ,并对现代分子生物学技术在林木遗传改良应用中存在的主要问题和应用前景进行了讨论     

转玉米PEPC基因杨树的光合生理特性分析

以转PEPC基因南林895杨和对照(南林895杨)为材料,分析不同转基因植株的光合生理参数。结果显示:转PEPC基因杨树与C4光合途径相关的酶活性比对照增高,PEPC活性增加较为明显,最高达38.6%。转PEPC基因杨树表现较强的对强光利用能力,其光饱和点比对照提高约10%～20%,饱和点时的光合速率比对照高17.7%～58.1%。转PEPC基因杨树光补偿点低于对照,利用弱光的能力增强;CO2饱和点低,比对照低22.2%～44.4%;CO2补偿点也较低,比对照降低58.1%～76.5%,表明对CO2的利用效率较高。此外,转基因杨树羧化效率增高,比对照增加最高达62.3%。     

杨树工业用材林的定向培育

本文列泽了国外利用杨树作为工业用材和采取定向培育所取得的成功经验。讨论了我国杨树人工林发展的现状及存在的问题,为杨树人工林朝着具有“定向、速生、丰产、优质、稳定、高效”等目标发展提供了参考性建议。