为研究西南桦(Betula alnoides)中木质素生物合成途径的关键酶4-香豆酸:辅酶A连接酶的调控机制,本研究采用RT-PCR技术从西南桦中克隆得到一个具有完整开放阅读框的4-香豆酸:辅酶A连接酶基因(Ba4CL,NCBI登录号为MK959316),该基因全长1 629 bp,共编码542个氨基酸.西南桦Ba4CL与光皮桦(Betula luminifera,ACJ38668.1)4CL 的蛋白序列同源性为99.63％,与白桦(Betula platyphylla,AAV65114.1)4CL同源性为99.45％;Ba4CL基因拥有4CL基因家族的保守域及具有保守序列SSGTTGLPKGV和GEICIRG,Ba4CL与桦木属植物白桦和光皮桦聚在一起.Ba4CL基因在西南桦的根、小枝、树皮和叶片中均有表达,且在小枝中表达量最高,树皮次之.本研究为培育西南桦优良用材品种提供参考.

测土配方施肥可以培肥地力、保护生态、协调养分、防治病害,对有限肥源的合理分配具有极其重要的意义.本研究以美国山核桃(Carya illinoensis Koch)一年生幼苗为研究对象,采用水培试验,在营养满足条件下进行叶片营养分析,并测定试验处理前后霍格兰营养液氮磷钾浓度的变化,推算美国山核桃幼苗吸收氮磷钾元素比例,以此为营养诊断依据,通过氮磷钾肥不同组合的盆栽正交试验,研究薄壳山核桃幼苗需肥量.结果表明,营养液水培下的美国山核桃树种叶片的全N、全P、全K元素的含量值分别为15.184、6.061、8.119g/kg,以此为诊断标准,得出美国山核桃一年生幼苗在土壤碱解氮、速效磷、速效钾分别为150.958、38.407、290.095 mg/kg水平时,最适宜其生长发育;美国山核桃一年生幼苗对肥料有效养分的吸收比例是碱解氮:速效磷:速效钾分别为3.56～3.93∶1∶7.55～12.96.

为了解降香黄檀叶绿体基因组密码子使用模式,该文利用Codon W 1.4.2和在线软件CUSP对降香黄檀叶绿体基因组中的52条基因编码序列密码子进行中性绘图、ENC-plot和PR2-plot分析.结果表明:降香黄檀叶绿体基因组密码子的3个位置上GC含量依次为GC1(46.01％)>GC2(38.98％)>GC3(27.80％).有效密码子数(ENC)范围为37.66～54.43,及ENC值>45的有37个;RSCU>1的密码子有29个,其中16个以U结尾、12个以A结尾.这些说明其偏好以A和U结尾,且偏性较弱.中性绘图分析显示GC12与GC3的相关系数为0.250,相关性不显著,回归系数为0.394;ENC-plot分析显示ENC比值位于-0.05～0.05区间外的基因有38个;PR2-plot分析说明在碱基的使用频率方面,U>A、G>C,说明降香黄檀叶绿体基因组密码子偏好性主要受选择的影响;19个密码子被确定为最优密码子.该研究为降香黄檀叶绿体基因工程、遗传多样性分析等研究提供了科学参考依据.

为研究肉桂酰辅酶A还原酶基因(CCR)在西南桦木质素合成中的作用机制,采用RT-PCR技术从西南桦中克隆得到1个具完整开放阅读框的肉桂酰CoA还原酶基因(BaCCR),该基因全长975 bp,编码324个氨基酸.序列比对分析显示西南桦CCR蛋白序列与胡桃、欧洲栓皮栎、梅、甜樱桃的蛋白序列相似性均在80％以上.BaCCR拥有CCR蛋白的NADP结合域和底物结合域KNWYCYGK.进化分析表明,BaCCR与梅、甜樱桃、亚洲棉、葡萄聚为一个枝系.转录模式分析表明,BaCCR基因在根和小枝中高量表达.

密码子偏好性广泛存在于各种植物中.本研究利用Codon W和在线软件CUSP分析西南桦(Betula alnoides)叶绿体基因组中的45条蛋白编码序列.结果 显示,西南桦叶绿体基因组的ENC值在36.86～56.10之间,密码子第3位上的GC含量为27.80％,RSCU＞1的密码子中有23个以A或U作为结尾,说明其密码子偏好以AU结尾;ENC与密码子第3位碱基的GC含量呈显著相关;3种图形分析均表明西南桦叶绿体基因组密码子偏好性受突变影响较大;最优密码子以C结尾的有7个,G结尾的有2个,U结尾的有1个.本研究为西南桦无性系地理种源鉴定、保持种源多样性提供了科学依据.

为了解乳油木叶绿体基因组密码子的使用模式,该研究以从乳油木叶绿体基因组中筛选得到53条长度大于300 bp且非重复的CDS (Coding DNA sequence)序列为材料,利用Codon W 1.4.2和在线软件CUSP分析其密码子偏好性.结果 显示,密码子第3位GC含量为27.47％,ENC范围在36.31～56.88,平均值为42.98.RSCU值大于1的密码子有28个,其中27个以A或U为结尾.中性绘图分析、ENC-plot分析和PR2-plot分析的结果显示乳油木叶绿体基因密码子偏好性主要受突变的影响.最优密码子为GGA、GAU、CAU和UUG.本研究结果为提高异源基因表达水平、改良乳油木重要经济性状等提供参考依据.

通过分析灰毛浆果楝叶绿体基因组密码子的使用特征,探讨影响其密码子使用偏性的主要因素.从灰毛浆果楝叶绿体基因组中筛选出54条编码序列(CDS),利用Codon W 1.4.2和CUSP软件计算不同基因密码子各位置的GC含量,以明确灰毛浆果楝叶绿体基因组密码子的使用偏性规律.结果显示:灰毛浆果楝叶绿体基因组密码子第3位碱基的GC含量为28.95％,即第3位密码子富含A和U,有效密码子数(Nec)在34.60～61.00之间,Nec 值大于45的CDS有39个;相对同义密码子使用度(URSC)值大于1的密码子有29个,其中16个以U结尾,12个以A结尾;中性绘图分析结果显示GC12 和GC3 的相关系数为0.098 4,相关性不显著,回归系数(对角线斜率)为0.137 9;基因Nec 比值大多数分布在－0.05～0.05区间外,即大部分基因Nec 值与预期值差距较大;相关关系分析显示,GC3 与GC1 、GC2 均未达到显著相关,Nec 与GC3 呈极显著相关.综合分析发现灰毛浆果楝叶绿体基因组密码子偏好性较弱,选择为主要影响因素,同时受到其他因素的影响.结合高表达优越密码子和高频密码子确定GUU、GUA、UCU、AGU、CCU、ACU、GGU、GCU、CAA、AAA、UGU、AGA和AUU等13个密码子为最优密码子.

概述了森林退化的研究状况、低效林的概念及成因,提出应统一低效林的专用名称及词义.针对低效林类型划分与判定实践中存在的问题,基于森林自然度、森林生态系统服务功能和生态系统多功能性研究的理念,建议在不同生态功能区划和立地环境条件下开展不同林分的生态系统功能研究,以此构建一套完整的可量化的低效林的分类技术体系.认为对低效林进行甄别与评价将有可能成为今后林业领域一个新的研究方向.

云南是我国的森林资源大省,由于长期忽视森林经营,导致云南省森林资源质量效益不高、 局部地区生态系统退化、 生态功能不强等问题突出.本文在进行云南森林资源现状质量评价以及多功能近自然森林经营的理念、 理论、 目标、 对象和技术与传统森林经营比较分析的基础上,针对制约云南多功能近自然森林经营的关键技术瓶颈,提出开展云南省林地立地分类与质量评价、 建立省级森林经营长期科研试验基地、 开展森林多功能近自然经营技术集成与示范推广、 加强科研基础条件平台和技术标准体系建设等技术创新重点领域的建议.

简要介绍了云南松的形态特征和林学特性,综述了退化云南松林及其生态系统功能的研究现状及发展趋势,针对目前退化云南松林划分及其生态系统功能评价中存在的问题和不足,建议在滇西地区开展云南松林生态系统功能的研究,以判别云南松林分类型,最终建立相应的评价体系.

In order to exploring Rhodiola crenulata nursery technology of Diqing,we have done the gibberellin (GA3)treated seed,sowing,collum cutting tests.Results showed that,800mg/L and 1 000mg/L concentration of gibberellin solution processing seed,can effective improve seed germination and germination potential.Seeding rate of 0.5g/m2,drills for sowing,soil thickness 0.1cm,could have a higher germination rate and seedling number and a faster align time.Seedling growth is gradually accelerating during sprouting to the growth of new leaves stop;Collum cutting at lower density could obtain more robust seedlings.When use seeds and collum to seedling,to promote Rhodiola crenulata seedling growth,it is needed to strengthen management and reasonable application of high content of phosphorus and potassium fertilizer at the right time,and thinning and weeding manner timely.

With dividing the branches & stems diameter (φ) of 4.5-year old Taxus yunnanensis sample trees into 9 grades,the biomass characteristics of bark and xylem in different grades were analyzed,and taxanes contents of different diameter samples,such as 10-DAB,baccatin-Ⅲ,7-xyl-taxol,10-deacet-taxol,cephalomannine,and taxol,were tested and contrasted.The results indicated that there was a significant decline for the proportion of samples' bark when φ ＞ 0.5 cm,and when φ ＞ 0.8 cm,there was the significant increase for the diameter of sampies' xylem.When 0.3 cm ＜ φ ＜ 1.49 cm and φ ＞ 4.00 cm,the ratio of dry weights of samples' bark and xylem decreased significantly with the increase of the diameter.There was a certain amount of taxol and other taxanes in the stem xylem of the saplings.And φ =0.3 cm,the branch diameter of the tree species,which was the significant node that relates to changes of taxanes contents of the branches.We thus suggest that the small branches with leaves (φ ＜ 0.3 cm) be used as main target and pricing basis in the cultivation,harvesting,and the purchase of the branches and leaves of medicinal raw material forests of T.yunnanensis.

In order to understand the species and distribution and the status of the local resources of Rhodiola L.in Diqing, we carried out the on-site field investigation at 11 survey areas.It was found that there were a total num-ber of 21 kinds of Rhodiola L., and the Meri Snow Mountain had 11 species.At an altitude of 2900m to 5100m range , the number of Rhodiola L.species showed a trend of increasing at first then decreasing with altitude in-crease.Most species of Rhodiola L.living at an altitude of around 4200m.Growth and reproduction of Rhodiola L.was limited by temperature and moisture, and the area where temperature was too high or too low with low mois-ture conditions is not suitable for their growth.

Experiments were conducted on afforestation with 2-year container and bare-rootTaxus yunnanensis seedlings in 2012 in Kunming, Yunnan province. Observations on conservation rate and growth traits had been implemented from 2012 to 2014. The result showed that the survival rate of two kind seedlings was over 95%. The height increment of bare-root seedlings had no evident difference with that of container seedlings in 2013, and ground diameter growth in 2014, but afforestation with bare-root seedling had lower cost. The experiment demonstrated that bare-root seedlings had about 3 months for recovering, when good water management could increase survival rate of seedlings. The annual growth cycle ofT. yunnanensis seedling could be divided into 3 stages, and the best time for bare-root seedling afforestation was March and April.

云南榧树(Torreya yunnanensis)是一种珍稀濒危保护植物,具有药用、食用、材用、油用和观赏等多种用途,开发前景广阔.本文介绍了云南榧树的分布和生态学特性,总结了育苗和造林技术要点.

With the development of Taxus industry,bark is becoming more important as the raw medicinal material due to the highest content of taxol in Taxus yunnanensis.With reference to classification of tree diameter class standard,the stem and branch diameter of Taxus yunnanensis in plantation could be divided into 5 classes.A study was carried out on 270 stem and branch samples from Kunming site and 67 sam-ples from Yibin site.The result shows that the content of fresh bark weight varied from 12.88% to 28.98%,the content of dry bark weight varied from 1 1.01%to 26.36%.The mean water content of stem and branch is 53.89%,and of bark is 60.74%.The variety of water content with the increase of stem and branch diameter class is irregular.The content of fresh and dry bark weight decreased obviously when the stem and branch diameter increased.The relationship between the bark content and the stem and branch diameter could be described by the power function equation.

This study investigates the best approach to make full use of land productivity and obtain maximum eco-nomic benefits through the landscape cultivation of Taxus chinensis.We used a randomized block design of 5-year old plantations of eight different densities (160 000 trees/hm2 , 80 000 trees/hm2 , 40 000 trees/hm2 , 26 667 trees/hm2 , 20 000 trees/hm2 , 17 778 trees/hm2 , 13 333 trees/hm2 , and 10 000 trees/hm2 ) to analyze the effect of afforesta-tion density on young Taxus chinensis plantation growth.We specifically investigated plant height, ground diameter, and lateral branch number of Taxus chinensis.Results showed that the plant height, ground diameter, and lateral branch number in the eight afforestation density types are significantly different .Four afforestation density types of 20 000 trees/hm2 (0.5 m×1.0 m), 17 778 trees/hm2 (0.75 m×0.75 m), 13 333 trees/hm2 (0.75 m×1.00 m), and 10 000 trees/hm2 (1.0 m×1.0 m), showed significantly higher plant height and ground diameter than other affroesta-tion densities.Ground diameter and lateral branch number increased as afforestation density increased .The compre-hensive evaluation value of the afforestation density of 0.5 m×1.0 m was 0.592 7, which was the largest of all affor-estation density types and the proper afforestation density for the landscape cultivation of Taxus chinensis.

In order to identify the effect of temperature on the content of Taxol and Taxane extracted from fresh leaf and green branch of Taxus yunnanensis, the test was made for Taxol and Taxane pretreated under different tempera-tures by using high performance liquid chromatograph .The result showed that there was no significant impact from drying temperature on the content of Taxol and Taxane.However, the appropriate drying temperature could be 90℃with 60 min in practice.

Cambodia is one of the highest forest coverage areas in the asia-pacific region, but this country is facing various problems in terms of sustainable forestry management . Based on field survey and literature review , the challenges of sustainable forestry management in Cambodia was analyzed and some suggested strategies were provid-ed in this study .The main challenges includes that the forestry development of this country heavily depended on international aids because of its weak economic condition , low management capacity and scarcity of substitute in-dustry .Its special hydrological and geographical condition leads to shortage of energy and difficulty in vegetation restoration.Several strategies such as development of substitute industry, strengthening independent governance, promoting plantation forest, and cultivating traditional culture related to forest protection were recommended in this paper.This study could provide some reference for regional forestry cooperation under the background of China' s One Belt and One Road strategy.

The domestic research progress of sub-alpine degraded forest ecosystem and vegetation recovery was summarized,including characteristics of sub-alpine degraded ecosystem,interference factors and mechanism of action,the natural regeneration of degraded ecosystem( limiting factors),and vegetation recovery,etc. from domestic scholars. The existing problems of research were put forward,and some suggestions and basis on the intensive study of sub-alpine degraded ecosystem were provided.