Resurrection plants which are able to quickly reactivate after falling into a period of anabiosis caused by dehydration have been very rare among angiosperms, especially among dicotyledons whose chlorophyll content and chloroplast structure little changed in the course of desiccation, therefore has been called homoiochlorophyllous desiccation-tolerant plants (HDTs). Another type of resurrection angiosperms that lost its chlorophyll during desiccation is called poikilochlorophyllous desiccation-tolerant plants (PDTs). HDTs have been received more attention because of simplicity of protection mechanism which is much easy to the study and utilization of the desiccation tolerance of resurrection angiosperms. Recent advances in studies of photosynthesis of resurrection angiosperms indicate that photochemical activities are sensitive indicators for the study of physiological state of resurrection angiosperms during desiccation and rehydration. Photochemical activities of resurrection angiosperms are inhibited with loss of water similar to those of general plants, however, the magic thing is that they could reactivate rapidly during rehydration even losing more than 95% water. Up-regulations in xanthophyll cycle and antioxidative systems as well as preservation in integrity and stability of photosynthetic membranes during desiccation may be very important to desiccation tolerance of resurrection angiosperms. The fact that phosphate treatment in rehydration stage also strongly influences resurrection indicated importance of studies on rehydration stages of resurrection angiosperms.
阳文龙 胡志昂 王洪新 匡廷云
Chloroplast genetic engineering, with several advantages over nuclear genetic engineering, is now regarded as an attractive new technology in basic and applied research, including deepening our understanding of plastid genome, engineering plant metabolic system， generating transplastomic plants with higher resistance to insect, disease, drought and herbicide and bioproducing of antibodies and vaccines. In this review, the principle and operating system for chloroplast genetic engineering and its application in higher plants have been discussed.
张景昱 张女原 宋艳茹 （中国科学院植物研究所，北京100093）
摘要： 叶绿体基因工程作为一项新技术具有一系列传统核基因工程所不具备的优点 ,在基础性及应用性研究中极具吸引力 ,已经成功应用于了解质体基因组 ,调控植物代谢系统 ,农作物抗旱、抗虫、抗病、抗除草剂及以植物为生物反应器生产抗体、疫苗等方面的研究。本文主要介绍叶绿体基因工程的原理、操作体系及其在高等植物中的应用。
通讯作者。E-mail: songyr @ ns.ibcas.ac.cn。
Although the research on Cordaites of the Cathaysian Flora in China started early in 1883, the study of the cordaitean cuticles began late in 1991. Up to now, four types of cordaitean cuticlesin situ and three types of dispersed ones have been reported from the Cathaysian Flora in China. However compared with the Euramerican Flora, the research work on cordaitean cuticles from the Cathaysian Flora in China is much more insufficient. In this paper, three kinds of dispersed cordaitean cuticles are described in detail from the Permian coal-bearing strata in China. Among these cuticles two kinds are collected from the roof shale of Coal Seam No. A1 in Shanxi Formation (Lower Permian) in Xinzhuangzhi Coal Mine of Huainan, Anhui Province, southern border of North China Subprovince of the Cathaysian Flora in China. The third one was collected from Coal Seam No.11 in the top of Longtan Formation (lower Upper Permian) in Dahebian Coal Mine of Shuicheng Mining District, Guizhou Province, South China Subprovince of the Cathaysian Flora in China. Comparison of these three kinds of cordaitean cuticles with the known ones from the Cathaysian Flora in China and from the Euramerican Flora is made. The authors consider that they are all new types of cordaitean cuticles. The significance they bear on palaeobotany is discussed.
李生盛 王士俊 贝月敏P
（1. 中国矿业大学，北京1000832. 中国科学院植物研究所，北京100093;3. 河北省邢台市第三中学，邢台054001）
摘要： 中国华夏植物区科达植物的研究历史虽然最早可上溯至 1883年 ,但直到 1991年才首次报道其角质层构造。到目前为止 ,中国华夏植物区总共描述了 4种科达植物原位角质层和 3种分散角质层。但与欧美植物区相比 ,有关中国华夏植物区科达植物角质层的研究工作还较薄弱。本文较详细地描述了 3种产自中国华夏植物区二叠纪煤系地层中的科达植物分散角质层。其中 2种采自华北亚区南缘的安徽淮南新庄孜矿山西组A1煤顶板 ,地质时代为早二叠世 ;另一种采自华南亚区的贵州水城矿区大河边矿龙潭组顶部的 11号煤层 ,地质时代为晚二叠世早期。将这 3种科达植物分散角质层与已知的欧美植物区和中国华夏植物区的种类进行了对比 ,认为它们都是新的类型。讨论了这 3种新的科达植物分散角质层所具有的古植物学意义。
通讯作者。E-mail:<wangsj @ ns. ibcas.ac.cn>。
The COP9 signalosome and the regulatory lid of the 26S proteasome are both eight-subunit protein complexes which are present in most eukaryotes. There is a one-to-one relationship between the corresponding subunits of the two protein complexes in terms of their size and amino acid sequences. Eight groups of subunits from the COP9 signalosome and the proteasome lid complex of different organisms are collected from all the databases at the NCBI website. The corresponding subunits of COP9 signalosome and proteasome lid complex share at least 12% amino acid identity and some conserved regions, and the conserved sites spread evenly over the entire length of the subunits, suggesting that the two complexes have a common evolutionary ancestor. Phylogenetic analyses based on the amino acid sequences of the corresponding subunits of two protein complexes indicate that every tree consists of two clades. The subunits from one of the two protein complexes of different organisms are grouped into one of the two clades respectively. The sequences of single-cell organisms are always the basal groups to that of multi-cell animal and plant species. These results imply that the duplication/divergence events of COP9 signalosome and regulatory lid of the proteasome genes have occurred before the divergence of single-cell and multi-cell eukaryotes, and the genes of the two complexes are independently evolved. The analyses of dN/dS correlation show significant Pearson’s correlations between 21 and 15 pairs of subunit-encoding sequences within the COP9 signalosome and the proteasome lid complex respectively, suggesting that those subunits pairs might have related functions and interacted with one another, and resulted in coevolution.
苏红文 瞿礼嘉 陈章良 顾红雅
摘要：COP9信号传导体和 2 6S蛋白酶体的调节盖子复合体皆为含有 8个亚基的蛋白复合体 ,在真核生物体中普遍存在 ,它们的相应亚基在大小和氨基酸序列上具有一一对应关系。从NCBI站点的所有数据库中获得了裂殖酵母、酿酒酵母、线虫、果蝇、哺乳动物和拟南芥等多种生物的复合体的亚基序列共 8组。COP9信号传导体与调节盖子复合体相应亚基之间的氨基酸序列一致性大于 12 % ,它们均具有一些保守的区域 ,而且保守位点分布均匀 ,表明它们来自于同一祖先。在基于氨基酸序列构建的系统发育树中 ,各组序列分别形成两个分支 :一个分支由COP9信号传导体亚基和相似蛋白组成 ,另一分支由相应的调节盖子复合体亚基和相似蛋白构成。各个分支中单细胞生物的序列位于动、植物序列的根部 ,表明COP9信号传导体与调节盖子复合体的基因重复发生在真核单细胞生物和多细胞生物分化以前 ,并且二者的亚基基因沿各自的方向独立进化。几乎所有编码两个蛋白复合体的基因在基因组中均为单拷贝 ,第Ⅴ、Ⅵ组的亚基保守程度最高 ,暗示着它们在复合体中起着关键的作用。对COP9信号传导体和调节盖子复合体的相应亚基基因两两之间进行dN/dS的相关性分析 ,分别鉴定出 2 1和 15对亚基编码序列间具有显著的Pearson相关关系 ,推测其相应亚基间可能通过承担相互关联的重要的生物学功能而协同进化。
通讯作者。E-mail: guhy @ plum.lsc.pku.edu.cn。
Pinus squamata X. W. Li, a recently-described species of the Pinaceae, is an extremely endangered pine with only 32 individuals in the wild. This species was thought to be intermediate between P. bungeana Zucc. ex Endl. of subgen. Strobus and P. yunnanensis Franch. of subgen. Pinus by the original author. We made an effort to address the question of the phylogenetic relationship of this peculiar and important species in the context of the major groups of the genus Pinus by using sequences of the rbc L, mat K genes, rpl20-rps18 spacer, trn V intron of the chloroplast genome and the nuclear ribosomal ITS region. The results of the separated analysis and the combined analysis of the four cpDNA sequences and ITS sequence indicated that P. squamata was a stable member of subsect. Gerardianae and P. gerardiana Wall. was the closest species of P. squamata phylogenetically. As a result, the causes of the distribution pattern of subsect. Gerardianae were also discussed.
张志勇 杨俊波 李德铢
摘要： 五针白皮松 (Pinussquamata X .W .Li)是上世纪 90年代描述的一种中国特有松树 ,目前野外只有立木 32株 ,处于极度濒危状态。前人认为这个种可能是白松亚属 (subgen .Strobus)的白皮松 (P .bungeana Zucc .exEndl.)与松亚属 (subgen .Pinus)的云南松 (P .yunnanensis Franch .)的过渡类型 ,并将其归入白皮松组狐尾松亚组 (subsect. Balfourianae)。本文试图在前人分子系统学工作的基础上 ,检测五针白皮松 5个DNA片段 ,叶绿体基因rbcL、matK、rpl2 0-rps18间隔区和trnV内含子以及核糖体ITS ,将五针白皮松放在整个松属中探讨其系统位置。 4个叶绿体基因单独分析结果和它们的联合数据分析结果以及根据ITS得到的系统树均表明 ,五针白皮松是白皮松亚组 (subsect.Gerardianae)的一个稳定成员 ,其可能的姐妹群是西藏白皮松 (P .gerardiana Wall.)。对白皮松亚组的地理分布作了初步探讨。
关键词： 五针白皮松；系统学关系rbc L; mat K; rpl20-rps 18 间隔区；trnVE 内含子；ITS
通讯作者。E-mail:dezhli @ hotmail.com。
Characteristics of total soil seed banks and permanent soil seed banks in three microhabitats in a Mediterranean coastal sand dune were investigated by using natural germination method combined with physically scanning separation method. The composition and structure of soil seed banks were analyzed between the microhabitats by using functional group method. The distribution patterns of soil seed bank were also analyzed between the microhabitats. We also analyzed the relationship between seed size and seed persistence in soil. The results show greatly spatial heterogeneity existed in soil seed bank of the Mediterranean coastal sand dune, even in the same microhabitats seed distribution was uneven. Sometimes a great difference occurred between them. Microhabitats significantly affected the distribution patterns of total soil seed banks and seed banks of the functional groups. The open area generally had the greater densities of seeds, but the seed densities under shrub and in trail were lower than that in the open area. Legumes seeds accounted for 76.0% total persistent seed banks. Annual and perennial grasses produced transient seed banks as no seeds were retrieved from the sieved soils. Seed persistence of legumes, umbeliferaes, perennial forbs, compositaes, annual forbs, crucifer decreased gradually. They were 50.1%, 45.6%, 40.6%, 6.3%, 5.6% and 0.6% respectively in the soil. There was a positive relationship between seed size and seed persistence. Bigger seeds had higher persistence, and vice versa.
于顺利 Marcelo STERNBERC 蒋高明 Pua KUTIEL
2. 巴依兰大学，拉马特甘52900，以色列；3. 特拉维夫大学，特拉维夫，以色列）
摘要： 应用自然萌发法和物理筛选法相结合的方法 ,调查了地中海沿岸沙丘三种微生境土壤总种子库和永久种子库特征 ,用功能群的方法分析了微生境之间的土壤总种子库和永久土壤种子库的组成和结构差异 ,也分析了主要物种土壤种子库的微生境分布格局 ,分析了种子大小和土壤种子库中的种子永久性关系。发现地中海沿岸沙丘土壤种子库具有明显的空间异质性 ,即使在相同的微生境内 ,土壤种子库的分布也不是均匀的 ,甚至具有很大的差异 ;微生境对总的土壤种子库和各功能群的土壤种子库的分布格局具有显著的影响 ,开阔地区域具有最大的种子密度 ,而灌丛下和路径具有较小的种子密度 ;在永久土壤种子库中 ,豆科类植物种子在休眠种子中占有最大的比例 ,约为 76 % ,而一年生和多年生禾草未发现休眠种子 ,豆类、伞形科类、多年生阔草、菊科类、一年生阔叶草和十字花科类等种子在土壤中的永久性比例依次下降 ,分别为 5 0 %、4 6 %、4 1%、6 %、6 %和 1% ,微生境影响各功能群种子在土壤中的永久性。微生境显著影响大部分主要物种的土壤种子库分布 ;种子大小与其在土壤中的永久性为正相关 ,即大种子具有较高的永久性 ,小种子具有较低的永久性。
Two exotic species, Sonneratia caseolaris (L.) Engl. and S. apetala B. Ham., were introduced to Futian Mangrove Forest Nature Reserve, Shenzhen Bay, in 1993 for afforestation. Winter cold caused frigid harm but did not appear to be an obstacle to the introduction. The cold tolerance of the parental and filial generation increased in several years. The two Sonneratia spp. could propagate by seeds and disperse in Shenzhen Bay. While the two species grew faster than indigenous species, at the same time they promoted the growth of indigenous species, but they could not replace indigenous mangrove species. Suitable habitat was more important than the distance from the source in the natural spreading for the two species. The niche of the two species did not overlap with the niche of indigenous species. The two species did not self-regenerate, although they could disperse on localized area in Shenzhen Bay. Therefore, it was unlikely that the two species would pose ecological disaster.
昝启杰 ! 王伯荪 王勇军 李鸣光
（1. 中山大学生命科学学院，广州510275；2. 广东内伶仃福田国家级自然保护区，深圳518040）
摘要： 对深圳湾红树林引种的外来种海桑 (Sonneratiacaseolaris (L .)Engl.)和无瓣海桑 (S .apetala B .Ham .)的生态适应性、扩散现状及生态入侵的可能性进行了研究。结果表明 :海桑和无瓣海桑对深圳湾的气温、盐度、潮滩与土壤等基本适应 ,虽然极端低温是其生长定居的限制因子 ,但其子代的抗寒性逐渐增强 ,在局部区域有一定的繁殖力和扩散力 ,生态效益明显。从种群生物生态学特性、生态位理论、群落更新理论等方面分析认为 ,海桑和无瓣海桑在深圳湾造成生态入侵的可能性不大。
A dynamic biogeochemical model was used to estimate the responses of China''s terrestrial net primary productivity (NPP), soil heterotrophic respiration (HR) and net ecosystem productivity (NEP) to changes in climate and atmospheric CO2 from 1981 to 1998. Results show that China''s total NPP varied between 2.89 and 3.37 Gt C/a and had an increasing trend by 0.32% per year, HR varied between 2.89 and 3.21 Gt C/a and grew by 0.40% per year, Annual NEP varied between -0.32 and 0.25 Gt C but had no statistically significant interannual trend. The positive mean NEP indicates that China''s terrestrial ecosystems were taking up carbon with a total carbon sequestration of 1.22 Gt C during the analysis period. The terrestrial NEP in China related to climate and atmospheric CO2 increases accounted for about 10% of the world''s total and was similar to the level of the United States in the same period. The mean annual NEP for the analysis period was near to zero for most of the regions in China, but significantly positive NEP occurred in Northeast China Plain, the southeastern Xizang (Tibet) and Huang-Huai-Hai Plain, and negative NEP occurred in the Da Hinggan Mountains, Xiao Hinggan Mountains，Loess Plateau and Yunnan-Guizhou Plateau. China''s climate at the time was warm and dry relative to other periods, so the estimated NEP is probably lower than the average level. China''s terrestrial NEP may increase if climate becomes wetter but is likely to continue to decrease if the present warming and drying trend sustains.
曹明奎 陶 波 李克让 邵雪梅 Stephen D PRIENCE2
（1. 中国科学院地理科学与资源研究所，北京100101；2. 马里兰大学地理系，美国20742）
摘要：应用一个生物地球化学模型(CEVSA)估算了中国陆地净初级生产力 (NPP)、土壤异养呼吸(HR)和净生态系统生产力 (NEP) 在1981～1998年期间对气候和大气CO2浓度变化的动态响应.结果显示,全国NPP总量波动于2.89～3.37 Gt C/a之间,平均值为3.09 Gt C/a,年平均增长趋势约为0.32%.HR总量变化范围为2.89～3.21 Gt C/a,平均值为3.02 Gt C/a, 年均增长0.40%.NEP总量变动于 -0.32和0.25 Gt C/a之间,在统计上没有明显的年际变化趋势.在研究时段内,年平均NEP约为0.07 Gt C/a,表明中国陆地生态系统在气候与大气CO2浓度变化的条件下吸收了碳,为碳汇,总的吸收量为1.22 Gt C,约占全球碳吸收总量的10%,与同期内美国由大气CO2和气候变化所产生的碳吸收量大致相当.尽管由于较高的年际变率,NEP在统计上没有明显的变化趋势,但NPP的增长率低于HR的增长率,说明在研究时段内,中国陆地生态系统的吸碳能力由于气候变化降低了.全国大多数地区年平均NEP接近零,明显的NEP正值区(即碳汇)出现在东北平原、西藏东南部和黄淮平原等地区,而大小兴安岭、黄土高原和云贵高原等地区NEP为负值(即碳源).研究认为,1981～1998年期间中国气候温暖、干旱,因此估算的NEP可能低于其他时段.如果气候进入一个比较湿润的时期,碳吸收量可显著增加,但若当前干旱和暖化趋势以此为继,中国的NEP可能会变成一个负值。
We investigated the osmotic stress and ion-specific effects on xylem abscisic acid (ABA), ion uptake and transport and gas exchange in one-year-old seedlings of Populus euphratica Oliv. Net photosynthetic rates (Pn) and unit transpiration rates (TRN) were both significantly decreased upon an osmotic shock caused by PEG 6000 solution (osmotic potential=-0.24 MPa) or a saline, which was applied by 50 mmol/L Na+-salts (NaNO3∶NaHCO3∶NaH2PO4=5∶4∶1, pH 6.8, osmotic potential=-0.24 MPa) or by 50 mmol/L Cl－-salts (KCl∶NH4Cl=1∶1, osmotic potential=-0.24 MPa). However, salt-treated P. euphratica plants maintained typically higher TRN than those exposed to PEG. Xylem ABA concentrations increased rapidly following the PEG treatment, exhibiting peaking values at 1 h, then returning to pre-stress levels, followed by a gradual increase. Similarly, both Na+-treated and Cl－-treated trees exhibited a rapid rise of ABA after salt stress was initiated. Notably, salt-treated plants maintained a relatively higher ABA than PEG-treated plants in a longer term. Collectively, results suggest that osmotic stress and ion-specific effects were both responsible for salt-induced ABA in P. euphratica: the initial rapid increase of xylem ABA appears to be a consequence of an osmotic shock, whereas specific salt effects seem to be responsible for ABA accumulation later on. Compared with Cl－-treated trees, a higher inhibitory effect on gas exchange (Pn and TRN) was observed in Na+-salt plants, resulting from its long-sustained ABA and higher salt concentrations in the xylem. Displacement of membrane-associated Ca2+ by Na+ and the lesser capacity in Na+ compartmentation in root vacuoles likely contribute to the high influx of Na+ and Cl－ in Na+-treated plants. Xylem K+, Ca2+ and Mg2+ concentrations were elevated by external Na+-salts and Cl－-salts, suggesting that P. euphratica maintained a higher capacity in nutrient uptake under saline conditions, which makes a contribution to its salinity tolerance.
陈少良 李金克 王天华 王沙生 Andrea POLLE Aloys HUTTERMANN
（1. 北京林业大学生物科学与技术学院，北京100083；2. 哥廷根大学森林植物研究所，哥廷根37077，德国）
摘要：研究了渗透胁迫和盐胁迫下一年生胡杨(Populus euphratica Oliv.)幼苗的木质部汁液脱落酸(ABA)、离子浓度及叶片气体交换的变化。PEG 6000(溶液渗透势—0．24MPa)、50mmol／L含钠离子的盐溶液(NaNO3：NaHCO3：NaH2PO4=5：4：1，pH6．8，渗透势-0．24MPa)和50mmol／L含氯离子的盐溶液(KCl：NH4Cl=1：1，渗透势-0．24MPa)3种处理都显著降低了苗木的净光合速率(Pn)和蒸腾速率(TRN)，但盐处理植株的TRN高于PEG处理的苗木。木质部汁液ABA的浓度在PEG处理后1h达到峰值，之后开始下降，降到对照水平后又逐渐回升。盐处理苗木的ABA也是在处理开始后就迅速升高，但之后ABA水平明显高于PEG处理的植株。结果显示，渗透胁迫和离子胁迫都能提高胡杨木质部汁液ABA的浓度：盐处理开始后ABA的迅速升高主要是渗透胁迫的作用，而此后离子胁迫(Na+和Cl-)对ABA水平的提高具有重要作用。钠盐处理对胡杨净光合速率和蒸腾速率的抑制作用高于氯盐处理，其木质部汁液中较高水平的ABA和盐离子(Na+和Cl-)是可能的原因。钠盐处理苗木的盐离子(Na+和Cl-)水平高于氯盐处理，主要是由以下两方面的原因所致：(1)细胞膜上的Ca2+被Na+所取代，增加了膜的透性；(2)胡杨根细胞液泡对Na+的区隔化能力较弱(与区隔Cl-相比)。另外，盐胁迫下胡杨能保持对营养元素K+、Ca2+和Mg2+的吸收，这也是其抗盐性强的重要原因。
通讯作者。E-mail: lschen @ bjfu. edu.cn。
The possible physiological mechanism of enhancement of cold tolerance by salicylic acid (SA) in banana seedlings (Musa acuminata cv. Williams 8188) was explored. Measurements of leakage electrolyte after 2 d of recovery at 30/22 ℃ (day/night) following 3 d of cold stress at 7 ℃ showed that pretreatment with hydroponic solution containing SA 0.3－0.9 mmol/L as foliar spray under normal growth conditions (30/22 ℃) could significantly enhance cold tolerance of banana plants. The highest enhancing effect of SA occurred at 0.5 mmol/L and it showed the lowest leakage rate of electrolyte or smaller leaf wilting area after 2 d of recovery at normal temperature from 3 d of 7 ℃ or 5 ℃ cold stress. Higher concentrations (≥2.5 mmol/L) of SA, however, caused more electrolyte leakage, indicating that they aggravated chilling damage. Enhanced cold tolerance by SA could be related to H2O2 metabolism. Compared with water-treated seedlings (control), SA 0.5 mmol/L treatment inhibited activities of catalase (CAT) and ascorbate peroxidase (APX), increased peroxidase (POX) activity, but did not affect the activity of superoxide dismutase (SOD) under normal growth conditions, and these changes might lead to an accumulation of H2O2, whereas SA pretreatment enhanced the activities of CAT and APX, and reduced the increase in productions of H2O2 and thiobarbituric acid-reaction substances (TBARS) during subsequent 7 ℃ cold stress and recovery periods. Exogenous H2O2 treatments (1.5－2.5 mmol/L) also increased cold tolerance of banana seedlings. Furthermore, pretreatment of banana seedlings with dimethylthiourea (a trap for H2O2) significantly inhibited cold tolerance induced by SA. These results suggested that endogenous H2O2 may be required for SA-enhanced cold tolerance. The significance of the interaction of SA, H2O2 and H2O2-metabolizing enzymes during cold stress has been discussed.
康国章 王正询 孙谷畴
（1. 中国科学院华南植物研究所，广州510650；2. 广州大学生物系，广州510405）
Glycine soja Sieb. et Zucc. plants living in saline soil in three provinces of China were treated with different salinity concentrations under different laboratory culture conditions (including solution, sand and field cultivation). The attachment shape and distribution on the surface of stalk and leaf of G. soja plants were observed with scanning electron microscopy (SEM), and the ultrastructure of glandular hair with transmission electron microscopy (TEM). Na+ and Cl- contents in the secretion of the leaf surface and inside the leaf of G. soja subjected to different treatments were measured. The Na+ relative contents in glandular cells, epidermal cells and mesophyllous cells of leaves under different salinities were determined by X-ray microanalysis. Results show that only glandular and epidermal hair exist on the surface attachments of leaves and stalks of G. soja plants. These glandular hair were similar in shape to some salt glands of Gramineae halophytes, and they attached to the vein on the leaf surface. The cell structure of the glandular hair showed the characteristics of common salt glands, such as big vacuoles, dense cytoplasm, a great deal of mitochondria, chloroplast, plasmodesmata and thicker cell walls, etc. The results of Na+ and Cl- contents in the leaf secretion and inside the leaf showed that the glandular hair executed the function of salt-secretion, and when treated with the salt gland inhibitor the salt-secretion process was inhibited. As a result, Na+ and Cl- were mainly accumulated inside G. soja leaves. The results of Na+ X-ray microanalysis under different salinities proved that the three cells of the glandular hair, especially the top cell, possessed strong competence for Na+ accumulation. Above all, the glandular hair were the salt gland, and no other kind of salt glands were found on G. soja plants. The secreting mechanism of the salt gland was also discussed.
周 三 赵可夫
摘要： 以中国3个省的盐生野大豆(Glycine soja Sieb. et Zucc.)为材料,在沙基培养、溶液培养和大田种植3种种植条件下用不同浓度的盐处理,观测了茎叶表面附着物的形态分布和腺毛的超微结构,测定了叶片腺毛分泌物中和叶片组织内部Na+和Cl-的含量变化,并对腺毛的3个细胞以及表皮细胞和叶肉细胞内的Na+相对含量变化进行了X射线微区分析.结果发现:盐生野大豆茎叶表皮上生长的附着物中只有表皮毛和腺毛,腺毛的形态类似于禾本科植物中的一些盐腺,叶片上的腺毛均生长在叶脉上;腺毛细胞内部结构具有一般盐腺的特点,如有大液泡,稠密的细胞质,大量的线粒体、叶绿体、胞间连丝以及较厚的细胞壁等.通过测定在无盐对照、盐处理和盐处理加盐腺泌盐抑制剂条件下盐生野大豆叶片腺毛分泌物中和叶片组织内部的Na+和Cl-含量,结果显示,盐生野大豆腺毛具有泌盐功能,加入泌盐抑制剂后,其泌盐作用停止;腺毛的3个细胞以及表皮细胞和叶肉细胞内的Na+在不同的盐浓度下的微区定位分析结果表明,盐生野大豆叶片的腺毛细胞有较强的积累Na+的能力.综合分析认为,盐生野生大豆的腺毛就是具有泌盐功能的盐腺,没有发现其他类型的盐腺.
!通讯作者。Tel: 0531-6187879; Fax : 0531-6180397; E-mail: zhaokefu @ 263.net。
Starch degradation in cells is closely associated with cereal seed germination, photosynthesis in leaves, carbohydrate storage in tuber and tuberous roots, and fleshy fruit development. Based on previously reported in vitro assays, βamylase is considered as one of the key enzymes catalyzing starch breakdown, but up to date its role in starch breakdown in living cells remains unclear because the enzyme was shown often extrachloroplastic in living cells. Recently we have shown for the first time that β-amylase is predominantly immuno-localized to plastids in living cells of developing apple fruit. But it remains to know whether this model of β-amylase compartmentation is more widespread in plant living cells. The present experiment, conducted in tuberous root of sweet potato (Ipomea batatas Lam. cv. Xushu 18) and via immunogold electron-microscopy technique, showed that βamylase visualized by gold particles was predominantly localized in plastids especially at periphery of starch granules, but the gold particles were scarcely found in other subcellular compartments, indicating that the enzyme is subcellularly compartmented in the same zone as its starch substrates. The density of gold particles (βamylase) in plastids was increasing during growing season, but the predominantly plastid-distributed pattern of βamylase in cells was shown unchanged throughout the tuberous root development. These data prove that the enzyme is compartmented in its functional sites, and so provide evidence to support the possible widespread biological function of the enzyme in catalyzing starch breakdown in plant living cells or at least in living cells of plant storage organs.
秦颖! 王毅 段长青 张大鹏
摘要： 淀粉降解代谢与种子萌发、叶片光合作用、块茎和块根贮藏及肉质果实的发育密切相关。体外酶学实验普遍认为 ,β- 淀粉酶是催化淀粉水解的重要酶之一 ,然而由于其在生活细胞中经常定位于叶绿体或质体之外 ,与淀粉基质在亚细胞水平上相互隔离 ,所以该酶在植物活体内的生理功能至今尚不清楚。我们最近首次发现 ,苹果果实生活细胞中的 β- 淀粉酶主要定位于质体内 ,与其淀粉基质居于同一亚细胞区域 ,但尚不清楚这一现象是否具有普遍性。本研究利用胶体金免疫电镜定位技术证明 ,甘薯块根生活细胞中的 β- 淀粉酶也是主要定位于质体内 ,围绕淀粉粒分布较多 ,其他亚细胞区域内 β -淀粉酶分布很少 ,说明该酶主要分布于其功能区域。质体内胶体金分布密度随着块根发育的推进显著增加 ,但 β- 淀粉酶区隔于质体内的亚细胞分布特点在块根整个生长发育期没有变化。这些结果明确地展示出甘薯块根生活细胞中 β- 淀粉酶与其淀粉基质居于同一亚细胞区域内 ,为 β- 淀粉酶普遍参与植物生活细胞或贮藏器官生活细胞中的淀粉水解提供了证据。
通讯作者。E-mail: zhangdp @ 95777.com。
A novel lipid occurred when cyanobacterium Synechocystis sp. PCC 6803 cells were grown in BG-11 medium with glucose applied. This lipid was determined to be a glycolipid, designated glycolipid-x(Glyco-x), by staining with α-naphthol and concentrated sulfuric acid. The occurrence of Glyco-x accompanies the disappearance of other lipids, especially DGDG. Glyco-x can also be observed in cells grown in BG-11 medium with the application of other carbon sources: fructose, maltose and lactose. Sodium thiosulfate, an effective scavenger of reactive oxygen intermediates, showed strong capability to inhibit glucose-induced occurrence of Glyco-x. In the presence of 0.3% sodium thiosulfate, Glyco-x could only be detected in cells grown in BG-11 medium with 100 mmol/L glucose applied in late-exponential phase. These results suggest that reactive oxygen species might be involved in the occurrence of Glyco-x in cyanobacterium Synechocystis sp. PCC 6803 cells grown in the presence of glucose.
硫代硫酸钠对蓝细菌Synechocystis sp. PCC 6803生长在含葡萄糖培养基中所产生的一种新糖脂的影响
王则能 许亦农 阳振乐 侯海彤 姜桂珍 匡廷云
摘要： 当蓝细菌Synechocystis sp.PCC 6803在添加葡萄糖的BG—11培养基中培养时，细胞出现了一种新脂。这种脂经浓硫酸／α—萘酚染色反应证实为糖脂，记为糖脂—x。这一糖脂的出现伴随着其他脂、尤其是双半乳糖甘油二酯含量的下降。此外，在添加果糖、麦芽糖、乳糖等其他碳源的培养基中生长的细胞中也检测到这一糖脂。活性氧猝灭剂硫代硫酸钠加入到培养基中能有效地抑制糖脂x的出现。当在BG—11培养基中加入0．3％硫代硫酸钠后，糖脂x仅能在培养基中添加高浓度(100mmol／L)的葡萄糖且细胞生长处于后指数期时检测到。这些结果表明蓝细菌Synechocystis sp．PCC 6803细胞在含葡萄糖的培养基中生长出现的一种新糖脂可能与活性氧有关。
The leaf structure, content and the storage location of aloin in the leaves of six species of Aloe L. were studied by means of semi-thin section, high performance liquid chromatography (HPLC) and fluorescent microscope. Results showed that all leaves consisted of epidermis, chlorenchyma, aquiferous tissue and vascular bundles. The leaves had the xeromorphic characteristics, including thickened epidermal cell wall, thickened cuticle, sunken stomata and well-developed aquiferous tissue. With the exception of this, there were remarkable differences in leaf structure among the six species. The chlorenchyma cells were similar to palisade tissues in Aloe arborescens Mill. and A. mutabilis Pillans, but isodiametric in A. vera L., A. vera L. var. chinensis Berg., A. saponaria Hawer and A. greenii Bak. A. arborescens, A. mutabilis, A. vera and A. vera var. chinensis included large parenchymatous cells at the vascular bundles, whereas no such cells were observed at the vascular bundles of A. saponaria and A. greenii. In A. arborescens, A. mutabilis and A. vera, the aquiferous tissue sheaths were present and composed of a layer of small parenchymatous cells without chloroplasts around the aquiferous tissue. While there were no aquiferous tissue sheaths in A. vera var. chinensis, A. saponaria and A. greenii. The HPLC revealed that the content of aloin was high in A. arborescens, low in A. vera, and very low in A. saponaria among the six species. The fluorescent microscopy showed that the yellow-green globule only appeared in the large parenchymatous cells of vascular bundles, vascular bundle sheath and aquiferous tissue sheath, but not in the chlorenchyma and aquiferous tissue. Consequently, the large parenchymatous cells of vascular bundles, vascular bundle sheath and aquiferous tissue sheath were the storage location of aloin. They were positively correlated with the content of aloin.
李景原 王太霞 沈宗根 胡正海
（1. 西北大学生命科学学院，西安710069；2. 河南师范大学生命科学学院，新乡(453002）
摘要： 应用半薄切片法、高效液相色谱法(HPLC)和荧光显微镜研究了6种芦荟叶的结构、芦荟素的含量和储藏芦荟素的组织.结果表明,6种芦荟叶均由表皮、光合组织、储水组织和维管束组成,都表现出明显的旱生植物肉质叶的结构特征,表皮由一层扁平的细胞组成,其外壁加厚,并覆盖着厚的角质膜,气孔器凹陷,储水组织发达.6 种芦荟叶的结构存在显著差异.木立芦荟(Aloe arborescens Mill.)和易变芦荟(A. mutabilis Pillans)的光合组织细胞呈长柱状,类似栅栏薄壁组织.中华芦荟(A. vera L. var. chinensis Berg.)、库拉索芦荟(A. vera L.)、皂叶芦荟(A. saponaria Hawer)和绿芦荟(A. greenii Bak.)则为等直径薄壁细胞.木立芦荟、中华芦荟、易变芦荟和库拉索芦荟的维管束中有大型薄壁细胞,皂叶芦荟和绿芦荟的维管束中无大型薄壁细胞.木立芦荟、易变芦荟和库拉索芦荟在光合组织和储水组织之间有一层不含叶绿体的小型薄壁细胞,包围着储水薄壁组织,称之为储水组织鞘.中华芦荟、皂叶芦荟和绿芦荟则没有储水组织鞘.HPLC测量结果表明,木立芦荟叶芦荟素含量最高,库拉索芦荟和易变芦荟次之,中华芦荟、皂叶芦荟和绿芦荟含量最低.荧光显微镜观察结果表明,在紫外光和蓝光下,黄色和黄绿色小球体仅存在于维管束的大型薄壁细胞、维管束鞘和储水组织鞘中,而光合组织和储水组织中没有黄色和黄绿色小球体.因此,维管束中大型薄壁细胞、维管束鞘和储水组织鞘是芦荟素等蒽醌类物质的储藏场所.综上所述,芦荟素含量与维管束的大型薄壁细胞、维管束鞘和储水组织鞘的情况密切相关.
通讯作者。E-mail: Huzhenghai @ yahoo.com.cn。
Fine structure and elemental composition of envelopes of 10 taxa of Trachelomonas and Strombomonas from natural freshwater bodies in China were studied and phylogeny of both genera were discussed. The results indicate that iron (Fe) and silicon (Si) are the primary mineral elements of the envelopes. Composition of mineral elements was uncorrelated with envelope color, however, it was highly correlated with the microarchitecture of the envelopes. Content of Si was higher than that of Fe in all species of Strombomonas and some species of Trachelomonas with rough surface. In most species ofTrachelomonas, especially those with dense and smoothy surface, content of Fe was higher than that of Si. Based on the above results, we propose to assign those species of Strombomonas into Trachelomonas and consider them as a group of the latter. These species were the most primitive among the group with envelopes in Euglenaceae.
王全喜 刘洪家 于 晶 孙世琴 张大维 包文美
摘要： 对采自自然水体中囊裸藻属 (Trachelomonas)的 8种和陀螺藻属 (Strombomonas)的两种藻类的囊壳微细结构和元素组成进行了比较分析 ,并探讨了这两个属的系统演化关系。结果表明 :组成囊壳的矿质元素主要是铁和硅 ,在陀螺藻和表面粗糙的囊裸藻中 ,硅的含量较高 ,铁的含量相对较低 ;在大多数囊裸藻中 ,尤其是表面致密、光滑的种类中 ,铁的含量较高 ,硅的含量较低 ,矿质元素的组成与囊壳的颜色无直接关系。建议将陀螺藻属 (Strombomonas)撤消 ,原陀螺藻属的种作为囊裸藻属 (Trachelomonas)中的一个种组 (Group) ,它们是裸藻科中最原始的具囊壳的类群。
通讯作者。Tel: 021-64322931; E-mail: wangqx@ shtu.edu.cn。
A 1 539 bp squalene synthase (AaSQS) cDNA was cloned from a high-yield Artemisia annua L. strain 001 by reverse transcription-polymerase chain reaction（RT-PCR）. The amino acid sequence of AaSQS is 70%, 77%, 44% and 39% identical to that of squalene synthases from Arabidopsis thaliana, tobacco, human and yeast, respectively. The AaSQS genomic DNA has a complex organization containing 14 exons and 13 introns. Full-length or C-terminal truncated cDNA was subcloned into prokaryotic expression vector pET30a and the constructed plasmid was introduced to Escherichia coli strain BL21 (DE3) for induced overexpression. No squalene synthase protein with expected molecular mass was observed in E.coli containing the putative full-length squalene synthase cDNA, however, overexpression in E.coli was achieved by truncating 30 amino acids of hydrophobic region at the carboxy terminus.
摘要： 用RT-PCR方法从青蒿(Artemisia annua L.)中克隆了一个1 539 bp全长鲨烯合酶cDNA.青蒿鲨烯合酶氨基酸序列与拟南芥、烟草、人类、酵母鲨烯合酶的一致性分别为70%、77%、44%和39%.青蒿鲨烯合酶基因组DNA结构很复杂,包括14个外显子和13个内含子.全长的或C末端截短的鲨烯合酶cDNA被克隆进原核表达载体pET30a并在大肠杆菌(Escherichia coli) BL21(DE3)中诱导表达.但在含有全长的鲨烯合酶cDNA的大肠杆菌中并没有观察到预期大小的鲨烯合酶表达,而C末端截短疏水区30个氨基酸的鲨烯合酶可在大肠杆菌中过量表达.
通讯作者。E-mail: <hcye @ ns.ibcas.ac.cn>。
In this study, we reported the repaid construction of a molecular marker linkage map of rice (Oryza sativa L.). An F2 population from the cross between Annong S-1 and Nanjing 11 was used to construct a genetic linkage map of rice. Total of 142 newly screened AFLP markers and 30 anchor markers (25 SSR markers and 5 RFLP markers) were mapped on the 12 chromosomes covering 1 537.4 cM of rice genome. The average interval between these markers was 9.0 cM. The total work which usually was finished in more than one year was finished within only 3 months by one person. This is the first plant AFLP map developed in China. A new thermosensitive genic male sterile gene in rice, tms5, was tigged and mapped onto chromosome 2 during the development of the linkage map.
通讯作者。Tel: 010-64889378; E-mail: bwang @ gebetucs.ac.cn。
Apical dominance is a phenomenon that the growth of axillary meristems is inhibited by the primary shoot or inflorescence. Recent researches have begun to reveal the molecular mechanisms of apical dominance by isolating and identifying mutants with altered apical dominance. Here we report isolation of a bushy and dwarf 1 (bud1) mutant from Arabidopsis thaliana L. through a T-DNA tagging approach. The phenotypes of bud1plants include loss of apical dominance, reduced plant size and dwarfism, suggesting that the bud1 mutant may be involved in auxin metabolism, transport or signalling. Using a reporter gene driven by an auxin-responsive promoter, we found that the expression pattern of auxin response element was altered in bud1. The auxin sensitivity and transport assay indicates that these two processes are normal in bud1. These results suggest that the bud1phenotypes may result from an alteration in auxin metabolism. Genetic analysis demonstrates that bud1 is a semidominant mutant and cosegregates with a T-DNA insertion, which indicates that BUD1 gene could be cloned by iPCRapproach.
戴 亚 付志明 李家洋
通讯作者。Tel: 010-64852855;Fax: 010-64873428; E-mail: jyli @ genetics.ac.cn。
Two novel polyhydroxylated steroidal sapogenins, wattigenin B ((25R)-spirost-1β, 2β, 3β, 4β, 5β, 6β, 7α-heptol, 1) and wattigenin C ((25S)-spirost-1β, 2β, 3β, 4β, 5β, 7α-hexahydroxyl-6-one, 2), together with two known sapogenins, kitigenin (3) and convallagenin B (4), were isolated from the fresh rhizomes of Tupistra wattii Hook. f. The structures of the compounds were determined on the basis of spectroscopic analysis. The four sapogenins were evaluated for the cytotoxicities on the cancer cell line K562 and A2780a in vitro. Compounds 1-4 were obtained from the plant for the first time.
沈 平 王三龙 杨崇仁 蔡 兵 姚新生
（1. 沈阳药科大学，沈阳110016;2. 中国科学院昆明植物研究所，昆明650204；3. 北京生物医药研究所，北京100091）
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