欧洲山场优良种质保存的新技术

本文对欧洲杨优良质保存新途径进行探讨。试验结果表明，愈伤组织或分化试管苗作为保存材料，效果很好；在低温下保存时，保存期长，保存率高；欧洲山杨３－１和欧洲山杨３－２保存温度为２－４℃，而欧洲山杨３－３为４℃；在ＭＳ培养基中增加激素含量（０．１－０．２ｍｇ／Ｌ）保存种质效果好，保存期可延长６个月。     

欧洲三倍体山杨根繁技术

利用3～4年生的欧洲三倍体山杨的根条进行无性繁育技术研究,通过对根条的选取、剪切、播种管理等环节的研究与分析,建立起了欧洲三倍体山杨无性快速繁殖体系,为生产实际应用提供技术支持与保障。     

桉树种质资源离体保存技术

利用限制生长法研究桉树(Eucalyptus spp.)种质资源离体保存技术并对保存材料的再生植株进行遗传稳定性检测,结果表明以MS+6-BA0.1 mg/L+NAA0.05 mg/L+蔗糖30 g/L为培养基,在低温(4±2)℃和弱光800 1x培养条件适宜桉树优良种质离体试管保存,保存期6个月,保存成活率达100%.保存6个月的试管苗在增殖和生根培养基上均能正常恢复生长.造林对比试验表明,其再生后代的田间生物学性状与对照植株无差异.运用ISSR标记对再生植株的遗传稳定性进行分析,未发现有遗传变异现象.     

青杄花粉保存方法试验研究

通过对不同保存方式下保存2~4年的同株青杄花粉生活力测定,结果表明:室温保存的青杄花粉效果较差,2年后花粉活力只有11.5%;低温保存条件下,随着保存时间的延长,花粉的生活力虽有下降,但不太明显,在4℃下和-20℃下保存青杄2年后,其生活力仍然在78%和80%左右,-20℃下保存的青杄花粉生活力较4℃稍强。因此,在-20℃条件下较长时间保存云杉花粉效果更为理想。     

草类-小檗沙棘灌木林群丛不同树种更新效果评价

为研究草类-小檗沙棘灌木林群丛不同树种更新效果,选择草类-小檗沙棘灌木林群丛不同微环境,设更新幼苗树种(A因素)和更新幼苗与灌木之间的距离(B因素)两组水平搭配,A因素设计A1(山杨苗)和A2(青海云杉苗)2个水平;B因素设计B_1(0.25m~2)、B_2(1.0 2)、B_3(4.0m~2)、B_4(≥9.0m~2)等4个水平,调查更新成活率、生长量。试验结果表明:(1)山杨更新幼苗与灌木之间的距离对山杨更新幼苗生长的影响显著;在B3(更新幼苗在4.0m~2中央即2.0m×2.0m左右)山杨幼苗生长效果最好,成活率达到78.6%。(2)青海云杉更新幼苗与灌木之间距离对更新幼苗生长的影响显著。在B1(更新幼苗在0.25m~2左右中央即0.5m×0.5m)幼苗生长效果最好,成活率达到96.7%.(3)在草类—小檗沙棘群丛条件下,采用青海云杉更新比山杨效果好。     

普通油茶花粉的超低温保存研究

为实现普通油茶花粉周年保存,对普通油茶3个无性系品种的花粉进行超低温保存研究。结果表明:花粉投放液氮前的含水量、预冻及解冻方式对超低温保存效果具有明显影响。3个品种花粉烘干(30℃)脱水2~5 h,花粉含水量达11.65%~15.70%时,超低温保存效果最佳;-26℃预冻(1 h)具有明显的预冻效果,液氮保存后花粉萌发率显著高于其他处理;超低温保存后的花粉采用38℃温水浴(3 min)快速解冻及-80℃(1 h)→-20℃(1 h)→4℃(1 h)逐级解冻,均能较好保持花粉活力。4℃低温干燥保存油茶花粉,能满足短期内(30 d)授粉的需要;超低温技术可以实现油茶花粉的周年保存,且保存一年的花粉较初始活力差异不显著。     

绿木霉T43发酵液不同菌剂剂型的制备及野外应用

采用摇瓶和发酵罐两种方法制备绿木霉Trichoderma virens T43发酵液,制备水剂和干粉剂两种菌剂剂型,测定其有效保存温度和保存期,评价了其对樟子松枯梢病Sphaeropsis sapinea的野外防治效果。结果表明:发酵罐发酵更有利于绿木霉T43的菌丝生长和抑菌活性成分代谢,制备的菌剂水剂抑菌效果好于干粉剂,其中水剂A2的10倍液室内抑菌效果最好,达到64.58%。4℃和25℃均可以长期保存菌剂,保存90 d后仍可发挥有效作用。在野外对樟子松枯梢病的控制试验中,水剂效果均高于干粉剂,水剂A1为78.88%,A2为81.66%;4种剂型对樟子松枯梢病的预防效果均在50%左右。     

欧洲山杨在山西的适应性评价

1984-1997年,山西省实施中德林业技术合作"速生树种造林"项目期间,从德国引进欧洲山杨到山西,在全省不同区域栽植试验。23年后调查欧洲山杨的生长表现情况,通过生长量分析,以及综合赋分适应性评价,结果表明,欧洲山杨在不同试验区域的生长量明显大于对照或与对照差异不显著;欧洲山杨在山西基本适应,最适生长区为山西中南部的山区。     

桃嫩叶及DNA处理方法用于RAPD分析的探讨

将桃 (AmygdaluspersicaL .)幼嫩叶 ,用格兰仕微波炉中火档干燥处理 3min、6min ,其中 6min处理明显影响DNA扩增 ;3min处理对DNA扩增没有太大的影响。桃幼嫩叶三种保存方式 ( - 72℃　 1 2 - 1 8d ,- 2 0℃　 30d ,- 2 0℃　 2 40d)DNA的质量和扩增带均较好。DNA在两种温度 ( 4℃和 - 2 0℃ )下保存 2 1 0d ,经过对其扩增 ,仍可获得很好的效果     

冀北山地3种次生林枯落物和土壤水文效应研究

对冀北山地3种天然次生林枯落物持水量和土壤水分特征进行了研究。结果表明:枯落物总储量为11.750～15.59t/hm2,最大持水量为44.55～49.18t/hm2之间。枯落物有效拦蓄量为白桦山杨混交林>山杨白桦五角枫混交林>白桦棘皮桦混交林。土壤容重均值的变化范围为0.72～0.95g/cm3,总孔隙度的变动范围为55.16%～60.21%。随着土层深度的增加,土壤容重呈现增加的趋势,总孔隙度减少的趋势,从土壤容重平均值来看,白桦棘皮桦混交林>白桦山杨混交林>山杨白桦五角枫混交林,总孔隙度的均值为山杨白桦五角枫混交林>白桦山杨混交林>白桦棘皮桦混交林。3种林分林地总蓄水量山杨白桦五角枫混交林为1 239.36t/hm2,白桦山杨混交林为1 194.02t/hm2,白桦棘皮桦混交林是1 135.75t/hm2,表明山杨白桦五角枫混交林林地储水能力最强。     

Effects of elevated concentrations of atmospheric CO2 and tropospheric O3 on decomposition of fine roots

Rising atmospheric carbon dioxide (CO2) concentration ([CO2]) could alter terrestrial carbon (C) cycling by affecting plant growth, litter chemistry and decomposition. How the concurrent increase in tropospheric ozone (O3) concentration ([O3]) will interact with rising atmospheric [CO2] to affect C cycling is unknown. A major component of carbon cycling in forests is fine root production, mortality and decomposition. To better understand the effects of elevated [CO2] and [O3] on the dynamics of fine root C, we conducted a combined field and laboratory incubation experiment to monitor decomposition dynamics and changes in fine root litter chemistry. Free-air CO2 enrichment (FACE) technology at the FACTS-II Aspen FACE project in Rhinelander, Wisconsin, elevated [CO2] (535 microl 1-1) and [O3] (53 nl 1-1) in intact stands of pure trembling aspen (Populus tremuloides Michx.) and in mixed stands of trembling aspen plus paper birch (Betula papyrifera Marsh.) and trembling aspen plus sugar maple (Acer saccharum Marsh.). We hypothesized that the trees would react to increased C availability (elevated [CO2]) by increasing allocation to C-based secondary compounds (CBSCs), thereby decreasing rates of decomposition. Because of its lower growth potential, we reasoned this effect would be greatest in the aspen-maple community relative to the aspen and aspen-birch communities. As a result of decreased C availability, we expected elevated [O3] to counteract shifts in C allocation induced by elevated [CO2]. Concentrations of CBSCs were rarely significantly affected by the CO2 and O3 treatments in decomposing fine roots. Rates of microbial respiration and mass loss from fine roots were unaffected by the treatments, although the production of dissolved organic C differed among communities. We conclude that elevated [CO2] and [O3] induce only small changes in fine root chemistry that are insufficient to significantly influence fine root decomposition. If changes in soil C cycling occur in the future, they will most likely be brought about by changes in litter production.     

种子超干燥贮存研究进展

论述了国内外超干燥贮存种子研究进展和存在的问题,展望了超干燥技术在今后种质资源保存中的发展前景。     

马褂木地理种源试验苗期及幼林生长测定报告

该试验为世界银行贷款国家造林项目第一期工程（ＮＡＰ）之科研推广计划中的阔叶树试验内容。报告对木兰科鹅掌揪属的２个种和１个人工杂交种即鹅掌揪（马褂木）、　北美鹅掌揪、杂交马褂木共１７个种源进行了育苗试验，２０个种源进行了造林试验。对１年生苗高生长及造林后１、２年生的树高及年度高生长量进行了测定，对各种源苗期、１年生、２年生幼林高生长进行了对比及方差分析。测定结果初步表明各种源间的高生长存在着显著的遗传差异。     

探析种质及种质资源定义

分析认为,现有的“种质”和“种质资源”定义均不妥当,因此重新定义了这两个概念。种质指遗传物质相对一致的同种生物的个体群,种质资源指一类生物或一个地区所拥有的种质的统称。     

胡桃楸苗木高生长种源家系变异规律初报

对林口县青山林场胡桃楸1年生苗高生长变异进行了分析。胡桃楸种源间和种源内部存在丰富的变异，变异系数范围在26．0％～32．7％之间，平均值为28．7％。3个种源间苗高差异极显著，其中，铁力种源高生长较快；穆棱种源高生长最差；最优种源与最差种源高生长相差25％。127个家系问苗高差异极显著，苗高前10名家系中有铁力种源9个家系、穆棱种源1个家系，前后10名家系高生长相差138％，种源内家系间存在丰富的遗传变异。变异系数在11．7％～48．2％之间。     

山茶属植物种质资源的搜集及基因库的建立利用研究

采用普通油茶大砧嫁接快速繁殖建成4个基因库,现已搜集保存种质资源2 267个号,其中山茶物种、变种161个,山茶花品种340多个,油茶农家品种、优株,无性系等1 605个。将不同纬度、海拔高度和生态条件下的物种、品种集中在同一地进行研究,提高了种质对环境的适应性和抗性,发挥了基因库的多种作用和效益。     

Isoprene emission inventory for the BOREAS southern study area

An isoprene emission inventory for a section of boreal forest in central Saskatchewan was developed based on measured emission rates from the two dominant isoprene-emitting species, black spruce (Picea mariana (Mill.) BSP) and aspen (Populus tremuloides Michx.). The micrometeorological gradient technique was used to determine isoprene emission factors for establishing the inventory. Isoprene fluxes were measured during each of the three BOREAS intensive field campaigns (IFCs) during the 1994 growing season. Measured isoprene fluxes varied from 0.04 to 3.3 mg C m(-2) h(-1) over the black spruce canopy, and from 0.05 to 7.3 mg C m(-2) h(-1) above the aspen forest. Midsummer standard isoprene emission fluxes were 1.2 mg C m(-2) h(-1) and 2.3 mg C m(-2) h(-1) (at 20 degrees C and photosynthetically active radiation (PAR) of 1000 &mgr;mol m(-2) s(-1)) for black spruce and aspen, respectively. With light and temperature differences accounted for, there was an apparent seasonal effect on emissions with the highest rates in the summer months. The total amount of isoprene emitted from this section of the boreal forest was estimated to be 8.6 Gg C year(-1), which is about 1% of the net ecosystem carbon exchange for the study area. Aspen was the largest contributor, accounting for approximately 70% of the total. Branch enclosure and relaxed eddy accumulation measurements made at the black spruce site were used to define the uncertainty associated with flux measurements. Emission rates obtained by the gradient, enclosure and relaxed eddy accumulation methods showed good agreement when normalized to standard light and temperature conditions. The coefficient of variance between the three techniques was 12% for summer (IFC-2) measurements. The sensitivity of the annual isoprene emission total to the assignment of mean irradiance and temperature was also examined. If the hourly mean temperatures were increased by 1 degrees C throughout the growing season, annual carbon loss due to isoprene emission would increase by 14% from 8.6 to 9.8 Gg C.     

Growth of white spruce underplanted beneath spaced and unspaced aspen stands in northeastern B.C.—10 year results

Establishing white spruce (Picea glauca (Moench) Voss) by planting it under established aspen (Populus tremuloides Michx.), stands has substantial potential as a technique for regenerating boreal mixedwood stands. The presence of an aspen overstory serves to ameliorate frost and winter injury problems and suppresses understory vegetation that may compete with white spruce. In this study we examine the growth of white spruce during the first 10 years after being planted underneath a 39 year-old stand of trembling aspen following thinning and fertilization. Results indicate successful establishment and reasonable growth rates of white spruce planted under thinned and unthinned aspen stands, even with aspen basal area of 51 m² ha⁻¹. Thinning of overstory aspen to 1000 or 2000 stems ha⁻¹ did not increase light reaching seedlings, but did result in improvements in light above the shrub layer and in diameter and height growth of the underplanted seedlings. However, these increases in growth of underplanted spruce may not justify the expense of thinnings. Fertilization of these stands prior to planting had no effect on spruce growth. Growth of spruce underplanted at this site near Fort Nelson was similar to that at two other stands near Dawson Creek, B.C.     

Corrigendum to: Growth of white spruce underplanted beneath spaced and unspaced aspen stands in northeastern B.C.—10 year results

Establishing white spruce (Picea glauca (Moench) Voss) by planting it under established aspen (Populus tremuloides Michx.), stands has substantial potential as a technique for regenerating boreal mixedwood stands. The presence of an aspen overstory serves to ameliorate frost and winter injury problems and suppresses understory vegetation that may compete with white spruce. In this study we examine the growth of white spruce during the first 10 years after being planted underneath a 39-year-old stand of trembling aspen following thinning and fertilization. Results indicate successful establishment and reasonable growth rates of white spruce planted under thinned and unthinned aspen stands, even with aspen basal area of 51 m² ha⁻¹. Thinning of overstory aspen to 1000 or 2000 stems ha⁻¹ did not increase light reaching seedlings, but did result in improvements in light above the shrub layer and in diameter and height growth of the underplanted seedlings. However, these increases in growth of underplanted spruce may not justify the expense of thinnings. Fertilization of these stands prior to planting had no effect on spruce growth. Growth of spruce underplanted at this site near Fort Nelson was similar to that at two other stands near Dawson Creek, B.C.     

我国药用植物种质资源研究现状

从药用植物种质资源清查和珍稀濒危种保护生物学研究,新药源研究,药用植物种质资源道地性研究,民族药用植物资源研究,有效成分的分离和药理学基础研究,药用植物种质资源遗传多样性及分类学研究等方面评述了我国药用植物种质资源的研究现状。针对其薄弱环节,提出了相关建议。