Assembly and analysis of the Populus deltoides mitochondrial genome:the first report of a multicircular mitochondrial conformation for the genus Populus

Genomics research of Populus deltoides,an important timber species that is widely planted worldwide,is an important part of poplar breeding.Currently,the nuclear and chloroplast genome of P.deltoides have been sequenced,but its mitochondrial genome(mitogenome)has not been reported.To further explore the evolution and phylogeny of P.deltoides,the mitogenome of P.deltoides I-69 was assembled using reads from Nanopore and Illumina sequencing platforms and found to consist of 802,637 bp and three circular chromosomes(336,205,280,841,and 185,591 bp)containing 58 genes(34 protein-coding genes,21 tRNA genes,and 3 rRNA genes).RNA analysis in combination with several species showed signifi cantly fewer RNA editingsites in the mitogenomes of poplar and other angiosperms than in gymnosperms.Sequence transfer analysis showed extensive mitogenome rearrangements in Populus species,and with evolution from lower to higher plants,tRNA transfer from chloroplasts to mitochondria became increasingly frequent.In a phylogenetic analysis,the evolutionary status of P.deltoides was determined,and the section Populus was supported.Our results based on the fi rst report of a multicircular conformation of the Populus mitogenome provide a basis for further study of the evolution and genetics of P.deltoides and other Populus species and for breeding programs.

美洲黑杨(Populus deltoides Marsh)×青杨(P.cathayana Rehd.)分子连锁图谱的构建

利用随机扩增ＤＮＡ多态性ＲＡＰＤ方法，在美洲黑杨（Ｐ．ｄｅｌｔｏｉｄｅｓＭａｒｓｈ）×青杨（Ｐ．ｃａｔｈａｙａｎａＲｅｈｄ．）３代谱系中分析分子标记，构建出第１张美洲黑杨×青杨分子连锁图谱。共从３００个１０ｍｅｒ随机引物中筛选出７９个适合引物，检测出可供构图的分离标记１８０个。该图谱由２０个连锁群，１１０个ＲＡＰＤ标记组成。总图距为覆盖基因组总长度的７０３５％，标记间的平均间距为１７２７ｃＭ．连锁群长度在３７１～１８９８，相应标记分别在３～１０。本图谱为杨树抗病、虫和其它性状基因定位提供了框架结构，为实现杨树分子遗传育种迈进了最重要的一步。

Pb胁迫对欧美杂交杨(Populus deltoides×Populus nigra)生物量分配格局及其Pb富集特性的影响

采用速生树种修复重金属污染土壤的方法近年来受到越来越多关注,但已有结果存在很大不确定性。为了解杨树在不同Pb胁迫条件下生长响应和Pb富集效果,以长江上游两种典型土壤(酸性紫色土和钙质紫色土)为栽培介质,采用盆栽试验方法,研究了不同Pb浓度处理下(CK:0mg·kg-1;T1:200mg·kg-1;T2:450mg·kg-1;T3:2000mg·kg-1)欧美杂交杨(Populus deltoides×Populusnigra)生物量生产与分配格局以及Pb吸收、富集特性。两种土壤条件下杨树各器官生物量及总生物量均表现出随Pb胁迫程度的增加而降低的趋势,Pb胁迫条件下杨树生物量分配格局在钙质紫色土中表现为茎>粗根>叶>细根。相同浓度Pb处理条件下,单株杨树总生物量均表现为钙质紫色土大于酸性紫色土。随着Pb处理浓度的增大,杨树各器官Pb含量及积累量显著增加。Pb胁迫使杨树对Pb的富集系数逐渐增大而耐性系数逐渐减小。T3处理条件下杨树对Pb的富集系数在酸性紫色土中较大,且各处理条件下杨树对Pb的耐性系数均为酸性紫色土中较大。这些结果表明,高浓度Pb胁迫条件下酸性紫色土中的欧美杂交杨表现出较好的吸收和富集Pb的特性,这为Pb污染土壤的生物修复提供了一定的科学依据。

镉胁迫对欧美杂交杨(Populus deltoides×Populus nigra)光合作用与生物量生产的影响

采用盆栽实验研究了生长在四川盆地典型Cd污染冲积土和紫色土上的欧美杂交杨(Populus deltoides×Populus nigra)对国家土壤环境质量标准中Cd浓度梯度(0、0.3、1.0、2.0 mg/kg)的光合响应和生物生产量。Cd处理显著降低紫色土上生长的杨树叶绿素a和叶绿素总量,增加气孔导度与胞间CO2浓度,增加凋落叶生物量,降低茎生物量、根生物量和单株总生物量。但是,Cd处理对冲积土上生长的杨树叶绿素特征、光合生理指标和生物量生产并无明显差异。尽管同一生长基质上不同Cd处理间杨树光合生理指标与生物量生产均有一定程度的影响,但紫色土上生长的杨树生理和生长特征均显著低于冲积土上生长的杨树。这些结果表明,自然条件国家土壤环境质量标准内,Cd污染并不对杨树生长构成较大威胁,而生长土壤基质的选择可能对杨树的栽培更为重要。这为Cd污染土壤区域城市森林建设和速生丰产林建设提供了一定的科学依据。

Isolation and characterization of two genes encoding polygalacturonase-inhibiting protein from Populus deltoides

Polygalacturonase-inhibiting proteins （PGIPs） are extracellular proteins that belong to the leucine-rich repeat （LRR） protein superfamily. PGIPs inhibit fungal polygalacturonases （PGs） and promote accumulation of oligogalacturonides, which activate plant defense responses. PGIPs play important roles in resistance to infection of pathogens. In this study, reverse transcriptase-polymerase chain reaction （RT-PCR） and RNA ligase-mediated rapid amplification of cDNA ends （RLM-RACE） were used to isolate the full-length PGIP cDNA from Populus deltoides （GenBank accession no. of PdPGIP2 and PdPGIP4：EF684913 and EF684912）. Domain analysis revealed that the deduced amino acid sequences of PdPGIP2 and PdPGIP4 had a typical PGIP topology. Phylogenetic analysis of known PGIPs indicated that the two PdPGIPs were clustered to the defense-related PGIP clade. Using real-time RT-PCR, the expression patterns of the two PdPGIPs following treatment with a fungal pathogen and defense-related signaling molecules were studied. The expression levels of PdPGIP2 and PdPGIP4 were both up-regulated when inoculated with the phytopathogenic fungus Marssonina brunnea. Therefore, it was proposed that the two PGIPs might be involved in the resistance to Marssonina brunnea in P. deltoides.

Influences of the Populus deltoids seedlings treated with exogenous methyl jasmonate on the growth and development of Lymantria dispar larvae

Lyantria dispar larvae were fed with the leaves of Populus deltoids seedlings exposed to methyl jasmonate （MeJA） for 24 h. The growth and development of the larvae were investigated, and phenolics contents in treated leaves including pyrocatechol, caffeic acid, coumarin, fernlic acid and benzoic acid were also surveyed by high-pressure liquid chromatography （HPLC）. Results indicated that approximate digestibility, efficiency of conversion of ingested food, efficiency of conversion of digested food, and weight of the larvae were inhibited obviously, especially from the sixth day, which may result from the increase of total phenolics contents in treated leaves. This result provides strong supports for MeJA acting as the airborne signal molecule between woody plants.

Morphological and physiological plasticity response to low nitrogen stress in black cottonwood(Populus deltoides Marsh.)

It is important to evaluate nitrogen use efficiency and nitrogen tolerance of trees in order to improve their productivity.In this study,both were evaluated for 338 Populus deltoides genotypes from six provenances.The plants were cultured under normal nitrogen(750μM NH_4 NO_3)and low nitrogen(5μM NH_4 NO_3)conditions for 3 months.Growth,chlorophyll content and glutamine synthetase activity of each genotype were measured.Under low nitrogen,heights,ground diameter,leaf area,leaf and root biomass,and chlorophyll contents were significantly lower than those under normal nitrogen level.Correlation analysis showed that nutrient distribution changed under different nitrogen treatments.There was a negative correlation between leaf traits and root biomass under normal nitrogen level,however,the correlation became positive in low nitrogen treatment.Moreover,with the decrease of nitrogen level,the negative correlation between leaf morphology and chlorophyll levels became weakened.The growth of the genotypes under the two treatments was evaluated by combining principal component analysis with a fuzzy mathematical membership function;the results showed that leaf traits accounted for a large proportion of the variation in the evaluation model.According to the results of comprehensive evaluation of plants under the two treatments,the 338 P.deltoides genotypes could be divided into nine categories,with wide genotypic diversity in nitrogen use efficiency and low nitrogen tolerance.As a result,26 N-efficient genotypes and 24 N-inefficient genotypes were selected.By comparative analysis of their morphological and physiological traits under the two treatments,leaf traits could be significant indicators for nitrogen use efficiency and nitrogen tolerance,which is of considerable significance for breeding poplar varieties with high nitrogen use efficiencies.

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 ofP. 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.

Compressive Strength Parallel to Grain Variation of Different Clones of Populus deltoides Marsh.

In order to explore the differences in the compressive strength parallel to grain （CSPG） between different clones and individual woods of Populus deltoides Marsh., the CSPGs of 5 15-year-old P. deltoides clones were determined and analyzed. The results showed that there were significant differences in CSPG of wood between different clones of P. deltoides . The CSPG of the tested clones reached more than 41 MPa, which was higher than the average compressive strength of P. deltoides （32.94 MPa）. Similar to the changes of stem height, the CSPG of the clones gradually increased with the increase of stem height. However, there were significant differences in CSPG of an individual plant at different tree heights. The CSPG of P. deltoides clones was related with their growth traits, but not significantly. Therefore, it is expected to achieve simultaneous and independent improvement on CSPG and the growth of P. deltoides , so as to get excellent individuals with fast growth and high CSPG.

南洞庭湖杨树(Populus deltoides)清理迹地恢复初期涨水前后土壤种子库特征

本文研究了南洞庭湖杨树清理1 a、2 a后的迹地(简称1 a和2 a)和未清理杨树洲滩(ck)涨水前后土壤种子库特征变化及其与地上植被的关系.结果显示:杨树清理迹地土壤种子库共萌发物种23科59属65种,涨水前后土壤种子库密度和种类均表现出1 a>2 a>ck的趋势,且随着土层加深而递减.退水后ck、1 a、2 a不同土层物种数量和密度较涨水前均有所减少,其中一或二年生物种较涨水前有所减少,多年生物种占比增加;湿生物种与中生物种数目较涨水前均有所减少,而2 a土壤种子库中生物种比例较涨水前有所增加.涨水前后土壤种子库Shannon-Wiener和Simpson指数变化较小,退水后Margalef指数较涨水前有所下降.退水后地上植被物种Shannon-Wiener和Simpson指数高于涨水前地上植被,而Margalef指数有所下降.涨水前Srensen相似性系数表现为1 a>2 a>ck的趋势,退水后表现为2 a>1 a>ck的趋势,涨水前后不同恢复年份土壤种子库和地上植被优势物种所占比例有所差异.研究表明,南洞庭湖杨树清理迹地退水后土壤种子库密度和种类显著下降,随着恢复年份和水淹频次的增加,一或二年生物种迅速减少,多年生物种比例增加,地上植被物种均匀性有所增加,可见水文因子是影响南洞庭湖杨树清理迹地种子库恢复能力的重要因素.

经三角肌入路微型锁定钢板内固定治疗肱骨大结节骨折

2019年8月~2021年3月,我科采用经三角肌入路微型锁定钢板内固定治疗16例肱骨大结节骨折患者,效果满意,报道如下。1材料与方法1.1病例资料本组16例,男10例,女6例,年龄19~58岁。均为新鲜闭合损伤。依据Neer分型均为二部分骨折。伤后至手术时间3~8 d。

三角肌结节指数联合术前因素构建老年肱骨近端骨折锁定钢板内固定失效的风险预测模型

背景:老年肱骨近端骨折是三大骨质疏松性骨折之一,解剖锁定钢板内固定是国内大部分医生治疗难以复位和复杂骨折类型的首选,但术后发生复位失效的概率较高,严重影响患者生活质量。目的:探讨三角肌结节指数与老年肱骨近端骨折术后复位失效的相关性,分析筛选出老年肱骨近端骨折术后复位失效的术前独立风险因素,并构建和验证临床预测模型的有效性。方法:收集2012年6月至2021年6月佛山市中医院符合标准的接受切开复位锁定钢板治疗的153例老年肱骨近端骨折患者的临床资料,根据其是否发生术后复位失效分为复位失效亚组和复位维持亚组。采用先单因素后多因素Logistic回归分析筛选独立风险因素,通过R语言构建列线图,内部验证采用Bootstrap法重抽样1000次后,通过Hosmer-Lemeshow拟合优度关联检验、绘制受试者工作特征曲线、校准曲线、临床决策和影响曲线评价其拟合优度、区分度、校准能力和临床应用价值。选择2013年6月至2021年8月收治的55例老年肱骨近端骨折患者作为模型外部验证组,评价预测模型的稳定性和准确度。结果与结论:①训练组153例患者中,44例患者出现钢板内固定术后复位失效,失效率为28.8%;多因素Logistic回归分析结果显示,三角肌结节指数[OR=9.782,95%CI(3.798,25.194)]、骨折端内翻成角移位[OR=4.209,95%CI(1.472,12.031)]、肱骨内侧柱粉碎[OR=4.278,95%CI(1.670,10.959)]是老年肱骨近端骨折术后复位失效的独立风险因素(P<0.05);②基于独立风险因素构建预测模型并绘制列线图,训练组Hosmer-Lemeshow检验结果显示,χ^(2)=0.812(P=0.976),曲线下面积=0.830[95%CI(0.762,0.898)];校准图结果表明模型预测风险和实际发生风险有较好的一致性;决策曲线和临床影响曲线结果表明列线图具有较好的临床适用性;③预测模型在验证组预测术后复位失效总正确率86%,曲线下面积=0.902[95%CI(0.819,0.985)];④提示三角肌结节指数<1.44、肱骨内侧柱粉碎、骨折端内翻成角移位是老年肱骨近端骨折术后复位失效的独立风险因素;⑤此次研究构建的风险预测模型内、外部验证表明该模型区分度、准确度和临床适用度较高,可用于个性化预测和筛选老年肱骨近端骨折术后复位失效的高危人群,模型的阈值风险概率高于65%时的预测高风险人数和实际发生人数高度匹配,临床医生应采用针对性治疗。

东北地区不同间伐强度青山杨人工林生长及木材性状变异

探究不同间伐强度对青山杨人工林生长及木材性状的影响,为东北地区培育杨树优质工业资源材提供理论基础。以18年生青山杨为试验材料,以初植株行距2 m×3 m为对照,设置3种强度的间伐处理(4 m×3 m、6 m×3 m、4 m×6 m)。间伐后第5年对试验林的生长性状(树高、胸径、2米径、冠幅)及木材性状(基本密度、纤维长、纤维宽、半纤维素含量、纤维素含量、综纤维素含量、木质素含量)进行了测定,并利用树高、胸径计算出单株材积及单位面积蓄积。方差分析结果表明,除基本密度外,各指标差异均达到极显著水平(P<0.01)。均值分析结果表明,林木各生长指标与木质素含量的均值在株行距为6 m×3 m时达到最大,其余各木材指标均在株行距为4 m×3 m或6 m×4 m时达到最大;各测定指标表型变异系数变化范围为3.35%~29.87%;除基本密度外,各指标重复力均超过0.590。相关性分析结果表明,各生长指标间均达显著正相关水平(0.690<r<0.993),而木材性状间及生长性状与木材性状间的相关性较弱。分别以生长性状、木材性状及联合生长与木材性状为评价指标对各处理进行综合评价后发现,Qi分别在株行距为6 m×3 m、4 m×6 m及4 m×6 m时达到最大。间伐能够促进林分生长,改良林木材性,且保留株行距为4 m×6 m时,林木材性及生长与木材综合改良效果较为优良;保留株行距为6 m×3 m时,林木生长效果最好。因此,今后可根据培育目标的不同选择适宜的间伐强度进行东北地区杨树优质工业资源材的培育。

韧带修复术对踝关节骨折合并三角韧带损伤患者骨代谢、促进恢复的作用分析

目的探讨韧带修复术对踝关节骨折合并三角韧带损伤患者骨代谢、促进恢复的作用。方法选择2019年1月至2022年1月成都市龙泉驿区中医医院骨科收治的111例踝关节骨折合并三角韧带损伤患者,采用随机数表法分为试验组(n=56)和对照组(n=55)。对照组给予切开复位钢板内固定术治疗,试验组加用韧带修复术治疗。比较两组术后恢复率、骨代谢、踝关节活动情况、临床评分变化情况及不良反应发生情况。结果术后试验组踝关节功能恢复优良率高于对照组(P<0.05);治疗后两组骨代谢及临床评分均改善,且试验组改善程度优于对照组(P<0.05);两组外翻角、外翻力度均升高,踝关节内侧间隙降低,且试验组优于对照组(P<0.05);两组不良反应比较差异无统计学意义(P>0.05)。结论在踝关节骨折合并三角韧带损伤中应用韧带修复术疗效显著,可有效改善患者骨代谢、促进恢复。

Arthroscopic release of the deltoid contracture

Background The deltoid contracture is an uncommon disorder. Long-standing contracture produces winged scapula, abduction and extension contracture of the shoulder. Surgical release has been considered the treatment of choice. However, the method of approach has not been well defined. The purpose of this study was to evaluate the results of arthroscopic release of the deltoid contracture. Methods A retrospective study was undertaken to evaluate the results of arthroscopic release in six patients （seven shoulders） who had a contracture of the deltoid muscle. All patients had arthroscopJc release. The abduction-contracture and horizontal-adduction angle was measured after operation. The average duration of follow-up was 16 months （range, from 4 to 41 months）. Results The preoperative abduction contracture resolved completely in three shoulders. Two had a residual abduction contracture of 5° to 7° and two had a poor result with 15° abduction-contracture angle. The average postoperative abduction-contracture angle was 6° （range, 0° to 15°）. The preoperative horizontal-adduction contracture was corrected, permitting at least 130° of adduction, in five shoulders. The remaining two shoulders had a postoperative horizontal-adduction angle of 120° and 110°. Overall, the average postoperative horizontal-adduction angle was 130° （range, 110° to 140°）. Conclusion Arthroscopic release is an effective surgical technique to treat the deltoid contracture.

经三角肌与三角肌胸大肌入路治疗NeerⅡ、Ⅲ型老年肱骨近端骨折的效果比较

目的:探讨经三角肌与三角肌胸大肌入路治疗NeerⅡ、Ⅲ型老年肱骨近端骨折的效果。方法:选取2021年1月—2022年12月景德镇市第一人民医院收治的48例NeerⅡ、Ⅲ型老年肱骨近端骨折患者,按照不同的手术方式分为观察组(经三角肌入路)和对照组(经三角肌胸大肌入路),各24例。对比两组手术情况、肩关节功能、凝血指标和疼痛程度。结果:观察组术中出血量少于对照组,骨折愈合时间和手术时间均短于对照组,差异均有统计学意义(P<0.05)。观察组术后1、6个月Neer肩功能评分均高于对照组,差异均有统计学意义(P<0.05)。观察组术后3 d凝血酶原时间(PT)及活化部分凝血活酶时间(APTT)均低于对照组,观察组FIB较术前降低,对照组FIB较术前升高,观察组低于对照组,差异均有统计学意义(P<0.05)。观察组术后3 d疼痛数字评价量表(NRS)评分低于对照组,差异有统计学意义(P<0.05)。结论:NeerⅡ、Ⅲ型老年肱骨近端骨折患者选择经三角肌入路方式进行手术,能够缩短手术时间和骨折愈合时间,减少术中出血量,有利于肩关节功能恢复,改善凝血指标及疼痛程度。

Henry入路三角肌双间隙治疗AOC型桡骨远端骨折的临床研究

目的:探讨Henry入路三角肌双间隙治疗AOC型桡骨远端骨折的临床效果。方法:选取2021年6月—2023年4月高安市人民医院收治的AOC型桡骨远端骨折患者102例作为研究对象,按随机数字表法分为两组,各51例,对照组采用传统入路方式治疗,观察组采用Henry入路三角肌双间隙治疗。观察两组手术相关指标、疼痛程度[视觉模拟评分法(VAS)]、手部功能恢复情况[上肢功能障碍评定量表(DASH)]、术后并发症发生情况。结果:观察组手术时间、骨折愈合时间及术后住院时间均短于对照组(P<0.05);观察组术中出血量少于对照组(P<0.05)。两组术后1 d、1个月、3个月的VAS评分与术前相比,差异均有统计学意义(P<0.05);观察组术后1 d、1个月、3个月的VAS评分均低于对照组(P<0.05)。术后3个月,观察组DASH评分低于对照组(P<0.05)。观察组并发症发生率为3.92%,对照组为15.69%,差异有统计学意义(P<0.05)。结论:Henry入路三角肌双间隙治疗AOC型桡骨远端骨折可减少术中出血量,缩短手术时间及术后住院时间,有效促进骨折愈合与手部功能恢复,减轻疼痛且并发症少。

棕榈酸帕利哌酮注射液三角肌肌内注射治疗精神分裂症的临床效果

目的:探讨精神分裂症患者接受棕榈酸帕利哌酮注射液三角肌肌内注射治疗的临床效果。方法:选取2020年3月—2022年1月临沧市精神病专科医院收治的120例精神分裂症患者作为研究对象,以投掷硬币法随机分为参照组与研究组,各60例。参照组给予利培酮口服治疗,研究组给予棕榈酸帕利哌酮注射液三角肌肌内注射治疗。比较两组临床症状、治疗效果、不良反应发生情况。结果:治疗前,两组临床症状评分比较,差异无统计学意(P>0.05);治疗3、6、12个月后,两组临床症状评分逐渐降低,且研究组低于参照组,差异有统计学意义(P<0.05)。研究组治疗总有效率高于参照组,差异有统计学意义(P=0.004)。研究组不良反应总发生率低于参照组,差异有统计学意义(P=0.011)。结论:精神分裂症患者采用棕榈酸帕利哌酮注射液三角肌肌内注射治疗的效果显著,可减少并发症,改善临床症状。

Differences in Growth and Physiological Characteristics in Different Growth Vigor Clones of Populus deltoids

To investigate differences in physiological characteristics of growth and physiological basis of high growth vigor in the first generation of Populus deltoides which are from different growth vigor clones,here we chose two groups of seedlings with different growth vigor:high（A） and low（B）.Indexes of phenotype and physiology were successively measured to study the growth,photosynthesis and nutrient absorption.There were significant or very significant differences in dry mass of root,stem, leaf and the total biomass between A and B.Dry matter of roots had the smallest proportion in different components,and the largest proportion was stem in A,while the leaf had the largest proportion in B.Changes in growth and physiological characteristics showed a certain regularity during June to September.All clones grew the most rapidly and physiological characteristics varied the most significantly in July.Correlation analysis showed that seedling height and ground diameter were both significantly correlated to leaf area,night respiration rate,NH4- uptake rate and the total photosynthetic rate（R】0.826,P【0.05）,suggesting that the seedling growth was mainly affected by their own total photosynthetic capacity,nutrient absorption and night respiration consumption.In general,A was superior to B in all these factors,which construct physiological basis of the high growth vigor.

美洲黑杨无性系苗木对不同光周期处理的生长与生理响应

【目的】研究不同光周期处理下美洲黑杨无性系苗木生长性状表现,筛选高效评价美洲黑杨光周期敏感性的性状指标,明确光周期对不同敏感度美洲黑杨生理状态的影响。【方法】以26个美洲黑杨无性系为研究材料,利用人工气候室设置2种光周期处理(光照16 h/暗期8 h,光照8 h/暗期16 h),通过对不同光周期处理下美洲黑杨12个生长性状多时间点连续观测分析,利用隶属函数法和主成分分析,获取美洲黑杨生长性状光周期敏感性综合评价D值。采用回归分析和通径分析,筛选适合美洲黑杨光周期敏感性评价的直接效应指标,选择不同光周期敏感度美洲黑杨无性系进行与生长监测同步的生理指标测定分析。【结果】1)方差分析结果表明,美洲黑杨12个生长性状在不同光周期处理下存在显著差异(P<0.05),短日照下美洲黑杨的叶长、叶宽、叶面积和比叶面积均显著大于长日照下的观测值,而苗高生长净值、地径生长净值、叶片干质量、茎段鲜质量、根系鲜质量、茎段干质量、根系干质量和节间数观测值均显著小于长日照处理。2)美洲黑杨光周期敏感性综合评价D值分析结果表明,茎段鲜质量、节间数、地径生长净值、苗高生长净值等指标对光周期敏感度综合评价值的直接效应较大(0.113~0.338),可以作为评价美洲黑杨光周期敏感性的性状指标,其中苗高生长净值更适合生产实际应用。3) 12个性状的光周期敏感度综合比较发现,相同种源内不同无性系光周期敏感度不同,26个美洲黑杨无性系中光周期综合敏感度最高的为LS8、TN3、WA1,最低的为QB7、LS5、TN6,结合苗高生长表现评选出3个高生长高光周期敏感度无性系LS9、LS4、TN4,3个低生长低敏感度无性系QB7、QB2、QB4。4)高生长高敏感度无性系在长日照处理下的Rubisco活性、磷酸丙糖异构酶活性、果糖-1,6-二磷酸醛缩酶活性均随处理时间增加而增强,总叶绿素含量呈先下降后上升的变化趋势,谷氨酰胺合成酶活性随处理时间增加而逐渐降低,在短日照处理下其Rubisco活性先增强后降低,总叶绿素含量逐渐降低;低生长低敏感度无性系的Rubisco活性和总叶绿素含量随处理时间增加而逐渐降低,在短日照处理下,其果糖-1,6-二磷酸醛缩酶活性先降低后增强,Rubisco活性总体随时间增加逐渐降低;不同美洲黑杨无性系在不同光周期处理下的酶活性和总叶绿素含量变化趋势不同。【结论】美洲黑杨生长性状表现受光周期显著影响,其中苗高生长净值、地径生长净值、茎段鲜质量和节间数都表现较强光周期敏感性,可作为美洲黑杨光周期敏感性评价的性状指标,结合苗高生长净值划分出高生长高敏感度和低生长低敏感度类型无性系。不同光周期敏感度的美洲黑杨对光周期变化的生理响应有明显差异,高敏感度无性系的果糖-1,6-二磷酸醛缩酶活性、谷氨酰胺合成酶活性对长日照更敏感,不同敏感度美洲黑杨的Rubisco活性在长日照下表现相反的变化趋势,可能导致不同光周期敏感度美洲黑杨的生长差异。研究结果可为杨树及林木光周期响应机理研究提供有益参考,筛选出的不同光周期敏感度美洲黑杨可为培育广适性杨树新品种提供种质。