25S rDNA在杨属植物染色体上的定位

利用荧光原位杂交技术对杨属(Populus)植物五个组中二倍体(2n=2x=38)代表种:毛白杨(P.tomentosa)、箭杆杨(P.nigravar.thevestina)、大叶杨(P.lasiocarpa)、小青杨(P.pseudo-simonii)、胡杨(P.euphratica);以及所发现的白杨组和黑杨组天然三倍体(2n=3x=57):毛白杨(P.tomentosa)、武黑1号(P.euramericana cv.Wuhei-1)进行了25S rDNA的染色体定位。二倍体毛白杨、箭杆杨、小青杨和大叶杨都具有4个25S rDNA位点,而胡杨只有2个较大的25S rDNA定位于1对小的染色体上,白杨和黑杨天然三倍体的两个种各有6个25S rDNA位点。同时作者还将杨属植物25S rDNA的分布变化与常规核型分析结果进行了比较。     

黄土高原丘陵区不同生境小叶杨人工林物种多样性及其群落稳定性分析

通过样地调查,对黄土高原丘陵沟壑区处于阴坡、半阴坡、半阳坡、阳坡4种生境条件下,经过30年发育的小叶杨人工林物种多样性,群落结构动态和土壤水分养分效应进行了系统研究,结果表明:(1)不同生境小叶杨人工林总体上物种丰富度、多样性指数和均匀度指数均呈现出阴坡>半阴坡>半阳坡>阳坡的趋势,且林内物种多样性指数表现为:草本层>灌木层;(2)不同生境条件下的小叶杨人工林年龄结构分析表明,尽管阴坡小叶杨长势相对较好,但更新幼苗数量相当有限,很难实现种群的自我更新,不适合作为人工林培育;(3)土壤含水量和养分因坡向不同而呈现出明显的差异,尽管阴坡和半阴坡的水分、养分条件相对较好,但也出现了枯梢、病虫害等衰老特征,因此阴坡、半阴坡的生境对小叶杨来说也不合适.未来应该对现有林地在保护的前提下,间伐衰老个体,补植和引入乡土物种,进行天然化培育.     

转双价抗虫基因毛白杨无性系85号抗虫性研究

以优化的毛白杨无性系85号最适遗传转化体系为基础,通过农杆菌介导法将Bt(CryⅠAc)和API双价抗虫基因导入毛白杨无性系85号基因组.在高浓度卡那霉素的培养基上诱导不定芽和根,初步选择到200株转化植株,PCR检测显示,66株呈阳性反应.Southern杂交和ELISA检测进一步证明,Bt(CryⅠAc)和API双价抗虫基因已整合到毛白杨无性系85号基因组中,并得到了表达.对转化植株用舞毒蛾幼虫进行饲虫试验,结果显示昆虫幼虫的死亡率高达60.0%~77.8%,且存活幼虫的生长发育也受到了明显抑制.研究结果为杨树抗虫育种提供了新的种质资源.     

干旱胁迫下胡杨茎流日变化分析——以塔里木河下游英苏断面为例

用PHYTALK植物生理生态监测系统对塔里木河下游英苏断面胡杨的茎流和相关环境因子的日变化进行了监测.结果表明:在极端干旱区塔里木河下游的胡杨茎流日变化表现多峰值,且夜晚仍保持一定流速;主枝与侧枝茎流日变化趋势相似,主枝流速高于侧枝;侧枝对环境变化响应更加灵敏,波动强烈,主枝相对侧枝,茎流变化响应迟钝且有明显滞后效应;茎流变化受太阳辐射、风速和大气温度影响明显,而其它环境因子如空气湿度、土壤湿度等影响则不大,气温与叶温表现出极佳相关性,气温与空气湿度呈显著负相关;同时,日变化中,不同时段起主导作用的因子不尽相同.     

杨树粒肩天牛的生物学特性

杨树粒肩天牛在福建省2a发生1代;老熟幼虫在第2年4月下旬至5月初开始化蛹,成虫出现期始于5月底6月初,6月中下旬到7月上旬为盛发期,9月上旬只见个别成虫;产卵期始于6月中旬,6月下旬至7月中旬为产卵高峰期;幼虫孵化期为6月下旬到8月中旬,7月上中旬为为盛发期;幼虫不越冬。杨树粒肩天牛成虫为补充营养所取食的树种较集中,主要是构树与桑树。杨树粒肩天牛幼虫对杨树危害严重,但成虫却不喜欢取食杨树,用杨树饲养的粒肩天牛成虫寿命很短,仅3-19d,不产卵;而以桑树为补充营养的雌成虫的平均寿命为55d、雄26.5d;以构树为补充营养的雌成虫的平均寿命为78d、雄45.5d,补充桑树与构树的粒肩天牛成虫均可正常产卵。雌雄成虫一生可多次交尾。雌虫有多次产卵现象,单雌每天产卵数量1-12粒不等。     

Free-air exposure systems to scale up ozone research to mature trees

Because seedlings and mature trees do not necessarily respond similarly to O(3) stress, it is critically important that exposure systems be developed that allow exposure of seedlings through to mature trees. Here we describe three different O(3) Free-Air Exposure Systems that have been used successfully for exposure at all growth stages. These systems of spatially uniform O(3) release have been shown to provide reliable O(3) exposure with minimal, if any, impact on the microclimate. This methodology offers a welcome alternative to chamber studies which had severe space constraints precluding stand or community-level studies and substantial chamber effects on the microclimate and, hence physiological tree performance.     

2种杨树光合色素和抗氧化系统对UV-B与NaCl胁迫的响应

以胡杨和俄罗斯杨(黑杨杂交种)为材料,通过设置增强UV-B辐射、NaCl胁迫(100mmol/L NaCl)、复合胁迫(增强UV-B辐射+100mmol/L NaCl)及对照(不额外施加NaCl和UV-B)4组处理,研究2种杨树对UV-B辐射、NaCl胁迫及其复合胁迫的生理响应及其种间差异。结果显示:(1)增强UV-B辐射、NaCl胁迫及其复合胁迫下,2种杨树的叶绿素含量降低,叶绿素a/b比值减小,类胡萝卜素含量升高;叶片中的膜脂过氧化产物(MDA)和H2O2含量均显著升高;但在复合胁迫下,俄罗斯杨MDA含量要明显低于各单一胁迫处理,而胡杨MDA含量和2种杨树H2O2含量均介于2种单一胁迫处理之间。(2)在3种不同胁迫条件下,俄罗斯杨和胡杨叶片中过氧化物酶(POD)和过氧化氢酶(CAT)活性比对照显著升高,且POD活性在复合胁迫下最高。(3)2种杨树叶片中渗透调节物质(脯氨酸、甜菜碱、可溶性蛋白)含量在各胁迫条件下均比对照明显升高,且脯氨酸和可溶性蛋白含量在复合胁迫下最高;胡杨甜菜碱含量在3种胁迫条件下的升高幅度均远大于俄罗斯杨,而俄罗斯杨可溶性蛋白含量升高的幅度在增强UV-B辐射和复合胁迫下却明显高于胡杨。研究表明,增强UV-B辐射、NaCl胁迫及其复合处理对2种杨树生长均造成不同程度的胁迫伤害,但2种杨树在复合胁迫下表现出的抗氧化保护能力比在2种单一胁迫下更强,因而复合胁迫对2种杨树的伤害更小,UV-B辐射可能与NaCl胁迫相互拮抗最终减缓了对植物的伤害。     

蚜虫对杨属植物不同寄生部位的形态适应(英文)

为了明确取食相同植物不同部位和营不同虫瘿的蚜虫是否存在形态适应,论文以取食杨属Populus植物的10种蚜虫为研究对象,基于蚜虫喙末端、各足跗节和爪的形态测量数据,对122个克隆的形态变异通过一般的统计描述、典型变量分析(canonical variates analysis,CVA)以及聚类分析等方法进行了研究。结果显示,不同的蚜虫克隆间形态特征存在分异,与不同的虫瘿类型和取食部位相关。3个典型变量分析明显地区分了形成虫瘿和不形成虫瘿的蚜虫克隆,在叶片上形成真虫瘿和伪虫瘿的克隆以及不产生虫瘿的克隆,并形成明显的克隆簇。而用于分析的形态学特征,如喙末端、跗节和爪的测量值,其一般统计描述的差异也支持这些区分。蚜虫自然种群不同克隆簇的区分很好地对应了不同的取食部位和不同的虫瘿类型,且各簇的形态特征体现了各自的特点,表明了蚜虫对杨属植物已经形成了良好的形态适应。同时,也初步讨论了不同蚜虫克隆簇形态适应产生的原因。并建议在基于形态特征探讨昆虫的系统发育关系和进行传统分类时,必须考虑昆虫形态特征的适应性;在深入研究昆虫与寄主植物相互之间关系时,需要将各种形态特征综合考虑并关注其它的影响因素。     

The EAG response and behavior of the Saperda populnea L. to volatiles from poplar branches

In order to investigate the effect of organic volatiles from poplar species on the host plants orientation of Saperda populnea, the essential oil in the 2–3 years old branches from the sapling or mature trees of Populus simonii Carr. and P. simonii Carr. × P. nigra L. were extracted using the steam distillation method. The chemical composition and relative content in essential oil from those branches was analyzed by GC–MS. The main components contained in those volatiles from the four kinds of branches are mainly aromatic compounds such as 1,2-cyclohexanedione, 2-cyclohexene-1-one, p-xylene and 1,2,3-trimethylbenzene and so on. The relative content of aromatic compounds contained in branches from saplings was higher than that contained in branches from old tress. EAG response and behavioral reaction of S. populnea L. to those four kinds of distillated essential oil were tested. The results shown that male and female adults of S. populnea L. shown significant choice behavior and strong olfactory response to those essential oil distillated from branches of P. simonii Carr. and P. simonii Carr. × P. nigra L.. The EAG bioassay of S. populnea L. to 10 kinds of monomers compounds which had relative higher contents was tested. The results shown that the EAG response of female adults of S. populnea L. to 1 mol L^?1 p-xylene was intensest and reached 1.027 mV, the strength of their EAG response to 0.1 mol L^?1 phenol took the second place. The EAG response of male adult of S. populnea L. to 1 mol L^?1 p-xylene was strongest and reached to 0.824 mV, the strength of their EAG response to 1 mol L^?1 salicylaldehyde took the second place. In the choice behavior test of S. populnea L. adult to monomeric compound carried out in ‘Y’ type olfactometer have found that female and male adult of S. populnea L. all appeared obvious positive taxis to 0.1 mol L^?1 p-xylene. The selection rate of female and male adults ware (76.7 ± 4.1)% and (71.7 ± 2.6)%, respectively. The selective reaction to 0.1 mol L^?1 1,2-cyclohexanedione and 2-cyclohexene-1-one were not obviously than that to 0.1 mol L^?1 p-xylene. The male and female adult of S. populnea L. appeared repelling behavior to 0.1 mol L^?1 salicylaldehyde.