WD40 repeat-containing proteins (WD40 proteins) serve as versatile scaffolds for protein-protein interactions, modulating a variety of cellular processes such as plant stress and hormone responses. Here we report the identification of a WD40 protein, XIW1 (for XPO1-interacting WD40 protein 1), which positively regulates the abscisic acid (ABA) response in Arabidopsis. XIW1 is located in the cytoplasm and nucleus. We found that it interacts with the nuclear transport receptor XPO1 and is exported by XPO1 from the nucleus. Mutation of XIW1 reduces the induction of ABA-responsive genes and the accumulation of ABA Insensitive 5 (ABI5), causing mutant plants with ABA-insensitive phenotypes during seed germination and seedling growth, and decreased drought stress resistance. ABA treatment upregulates the expression of XIW1, and both ABA and abiotic stresses promote XIW1 accumulation in the nucleus, where it interacts with ABI5. Loss of XIW1 function results in rapid proteasomal degradation of ABI5. Taken together, these findings suggest that XIW1 is a nucleocytoplasmic shuttling protein and plays a positive role in ABA responses by interacting with and maintaining the stability of ABI5 in the nucleus.

农田防护林是南疆三大生态安全屏障的重要组成部分.为优化南疆防护林体系结构、提高生物多样性和生态防护效果,以引种到南疆喀什地区的吴屯杨和新疆乡土树种新疆杨为研究材料,采用样地调查法对不同立地条件下的2种杨树的树高、胸径、保存率和累积生长量进行调查研究.结果表明,在3个试验样地中,吴屯杨的平均胸径均高于新疆杨,2种杨树的平均树高无显著差异.造林3年内2种杨树的树高累积生长量上升速度较快,栽植2年后,吴屯杨的胸径累积生长量高于新疆杨.在含盐量高达0.76%的伽师县,吴屯杨的保存率仍达到37.37%,高于新疆杨,说明吴屯杨的耐盐能力比新疆杨强,且吴屯杨的生长状况优于新疆杨.本研究为吴屯杨在南疆大面积推广种植提供了实践依据.

以2年生北高丛蓝莓(Vaccinium corymbosum L.)3个优良品种“蓝丰”、“公爵”和“布里吉塔”的苗木为实验材料,利用人工气候箱控制生长温度,探讨不同温度处理对北高丛蓝莓叶片气体交换和叶绿素荧光参数的影响.结果表明:随着温度升高,3个品种叶片的净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)和水分利用效率(WUE)均先升高后降低,最大值随品种的不同而发生变化;3个品种的细胞间CO2浓度(Ci)均一致性地呈现相反的变化趋势,30和35℃高温使Ci降低,而40℃高温又导致了Ci升高;相对电导率和叶绿素荧光参数Fv/Fm的测定结果表明,30和35℃高温对北高丛蓝莓叶片结构和功能的影响非常有限,40℃高温却导致其细胞膜结构的破坏;40℃高温对光系统Ⅱ反应中心及其电子传递链的结构造成了不可逆的严重损伤;不同北高丛蓝莓品种的抗高温能力存在很大差异,“布里吉塔”最强,“蓝丰”次之,“公爵”最弱.研究结果有助于深入理解温度对北高丛蓝莓产生影响的潜在机理,为蓝莓耐高温品种选育和引种工作提供理论依据.

[目的]探讨不同程度的高温对高丛越橘叶片气孔特征及其气体交换参数的影响.[方法]以6个高丛越橘(Vaccinium corymbosum L.)品种的2a生幼苗为试验材料(南高丛品种‘奥尼尔'‘海岸’和‘蓝脊’;北高丛品种‘公爵’‘布里吉他’和‘蓝丰’),利用人工气候箱控制生长温度的条件下,共设置4个温度处理,即对照(25℃)、轻度增温(30 ℃)、中度增温(35℃)和重度增温(40℃),利用印迹取样法及空间分析技术研究了6个越橘品种叶片气孔的结构特征和空间分布格局.利用Li-6400便携式光合测定系统测定了叶片的气体交换参数.[结果]研究发现叶片的气孔密度、气孔结构及其空间分布格局对增温产生的响应在南高丛和北高丛越橘2个类群之间没有明显的特异性区别.然而,高丛越橘叶片气孔特征对高温的响应在不同品种间却存在着较大的差异.高温改变了‘海岸'‘蓝脊'‘布里吉他’和‘蓝丰’的气孔结构特征,但没有对‘奥尼尔’和‘公爵’产生影响;同时,高温导致‘奥尼尔’和‘布里吉他’叶片气孔的空间分布变得更加规则.另外,高温处理导致高丛越橘品种叶片的净光合反应速率(Pn)、气孔导度(Gs)和蒸腾速率(Tr)均呈先升高后降低的趋势,但其最大值随着品种的不同而发生变化.[结论]高温条件下高丛越橘通过调整气孔结构特征和优化气孔的空间分布格局来进一步提高气体交换效率.然而,气孔结构和功能进行调整和优化的能力在品种间存在较大的差异,最终导致了各品种叶片气体交换参数对高温响应的不同,特别是在抵抗极端高温方面表现得尤为突出.

以文冠果种子为试材,设置10种不同催芽方法,包括水浴加热、不同浓度的H2SO4、KNO3、PEG-6000等试剂处理文冠果种子,诱导发芽后调查种子的发芽率、活力、发芽势等发芽参数,并对不同催芽方法进行了比较分析,筛选适合文冠果种子快速解除休眠的方法.结果表明:80℃水浴加热、4％ KNO3溶液、5％ PEG-6000溶液、GA3溶液、2％ KNO3溶液、10％ PEG-6000溶液、4℃蒸馏水浸种、50％ H2SO4溶液处理,均可不同程度的提高文冠果种子的发芽率,而高浓度H2SO4溶液处理对文冠果种子发芽有抑制作用;文冠果种子经80℃水浴加热10 min处理可使发芽率提高到55.83％,为未处理的9.3倍.

[目的]为南疆盐碱地区引种优良耐盐碱杨树品种提供理论依据.[方法]采用随机抽样调查的方法,以引种喀什地区的吴屯杨为主要研究对象,以新疆杨为对照,比较两种杨树的株高、地径、成活率及冠幅等指标,研究吴屯杨在南疆盐碱生境下的生长适应性.[结果]吴屯杨在喀什地区不同盐碱(pH值8以上)生境下均能正常生长,不同引种点中两种杨树的株高、存活率与相应引种点生境的土壤有机质含量高低顺序基本一致,土壤有机质含量、栽培年数是导致杨树株高、地径差异的主要因子.与当地新疆杨相比,伽师县和莎车县引种点的吴屯杨其地径显著高于本土树种新疆杨,两种杨树成活率无明显差异,喀什市引种点吴屯杨的冠幅显著高于新疆杨,麦盖提县两种杨树冠幅差异不显著.[结论]吴屯杨在不同引种点生境具有一定的适应性,可作为新疆杨的补充树种.

In this study, we investigated the effect of exogenous calcium and salicylic acid (SA) on Botrytis cinerea resistance in tomato seedlings. We treated a tomato strain susceptible to Botrytis cinerea with foliar spraying of water, SA, SA+CaCl2 and SA+EGTA (Ca2+ chelating agent) for one to five days. During the treatment, leaves were collected to analyze the reactive oxygen species (ROS) content, phenylalanine ammonia lyase (PAL) activity, chintase and β-1,3-glucanase levels, and the expression of pathogenesis related protein 1, 2, 3 (PR1, PR2, PR3). Three days after infection, the disease index was 74.8 in control plants, and 46.9, 38.5 and 70.3 in SA, SA+Ca and SA+ EGTA treated plants, respectively. SA treatment significantly increased ROS leaf accumulation, and activities of PAL, chintase and β-1,3-glucanase. These values were further enhanced in SA+Ca treated plants, but decreased in SA+EGTA treated plants. Application of SA significantly increased the expression levels of PR1, PR2a and PR3b, which were further elevated by the combination treatment with Ca2+. These effects were counteracted by the combination treatment of SA and EGTA. The transcription levels of PR2b and PR3a were up-regulated by 1-2 folds, and PR1, 2a and 3b by 2-5 folds in SA- and SA+Ca-treated plants relative to control. These data suggested that application of Ca2+ could synergistically increase SA-induced resistance to B. cinerea. The resistance was associated with ROS accumulation, therefore the increase in resistance might be through ROS ability to increase the activity of defense-related enzymes and expression levels of PR1, PR2a and PR3b.

Based on microdialysis experience in apoplast of poplar stems, the trace of proline in plant was detected by using the High -performance liquid chromatography ( HPLC ) method, precolumn derivatization method was studied. Phenyl isothiocyanate PITC- acetonitrile solution and triethylamine acetonitrile solution were applied to derivate the proline. Cyclohexane was used to extract proline, the sample could be directly injected in HPLC without subsequent pro-cessing. The detection conditions were determined: the SHIMADZU Inertsil ODS-SP column (250 mm × 4. 6 mm, 5 μm);column temperature:31 ℃;mobile phase A:0. 05mol·L-1 so-dium acetate solution, mobile phase B: acetonitrile-mobile phase A (1:1); Elution condi-tions:A:B (50:50);flow rate:1. 0 mL·min-1;detection wavelength:254nm;the injection volume was 20μL. The recovery rate of proline was 95. 1 -104. 2%. At last the proline con-tents of three poplar apoplast dialysis were detected by this method.

Expressions of ABA biosynthesis genes and catabolism genes are generally co-regulated in plant development and responses to environmental stress. Up-regulation of OsNCED3 gene, a key gene in ABA biosynthesis, has been suggested as a way to enhance plant drought resistance but little is known for the role of ABA catabolic genes during drought stress. In this study, we found that OsABA8ox3 was the most highly expressed gene of the OsABA8ox family in rice leaves. Expression of OsABA8ox3 was promptly induced by rehydration after PEG-mimic dehydration, a tendency opposite to the changes of ABA level. We therefore constructed rice OsABA8ox3 silencing (RNA interference, RNAi) and overexpression plants. There were no obvious phenotype differences between the transgenic seedlings and wild type under normal condition. However, OsABA8ox3 RNAi lines showed significant improvement in drought stress tolerance while the overexpression seedlings were hypersensitive to drought stress when compared with wild type in terms of plant survival rates after 10 days of unwatering. Enzyme activity analysis indicated that OsABA8ox3 RNAi plants had higher superoxide dismutase (SOD) and catalase (CAT) activities and less malondialdehyde (MDA) content than those of wild type when the plants were exposed to dehydration treatment, indicating a better anti-oxidative stress capability and less membrane damage. DNA microarray and real-time PCR analysis under dehydration treatment revealed that expressions of a group of stress/drought-related genes, i.e. LEA genes, were enhanced with higher transcript levels in OsABA8ox3 RNAi transgenic seedlings. We therefore conclude that that OsABA8ox3 gene plays an important role in controlling ABA level and drought stress resistance in rice.

越桔属植物是一类生存于林下环境的低矮灌木植被,该类植物群落的分布区通常位于北半球高纬度地区的寒带森林或苔原地带.为了预测全球变化背景下越桔属植物的响应和适应能力,文章综述了高纬度地区寒带森林灌木层中最具代表性的3个越桔属主要物种(欧洲越桔、红豆越桔和笃斯越桔)的最新研究进展,重点介绍了全球变化导致的气候变暖、大气CO2浓度增加、极端干旱事件、大气氮素沉降、积雪覆盖的改变以及紫外线辐射增强等不同环境因素对欧洲越桔、红豆越桔和笃斯越桔产生的影响,综合分析了越桔属不同物种对全球变化的生理生态学响应机制和适应策略.

The dialysis for three species of populus stems apoplast was carried out with a microdialysis system, and the concentration of Na+, K+ and Ca2+ in the dialysate was directly measured by the graphite furnace atomic absorption spectrometry (GF-AAS). The flow rate of perfusate was 1 μL min−1 and the cut-off molecular weight of probe was about 30 kDa. The test technique was applied to the research of poplar biochemical physiology due to its perfect characteristic of real-time and non-destructive detection. The recovery of the method was 95.8%–103.1%. The content of Na+ in Populus wutunensis, Populus simonii × P.euphratica” × P.sp and Populus simonii × (Populus pyramidalis + Salix matsudana) were 1034–1156 μg L−1, 1493–1611 μg L−1 and 1586–1703 μg L−1, respectively, K+ was 1012–1237 μg L−1, 941–964 μg L−1 and 1095–1201 μg L−1, and Ca2+ was 4976–5237 μg L−1, 4786–5042 μg L−1 and 5893–6142 μg L−1. This method could provide reliable data for the investigation of the change of ion concentration of plant to all kinds of external environment stress.

In order to identify S4'S4'homozygous genotype of sweet cherry,the AS-PCR identification system for S4′S4′homozygous genotype was established.The sweet cherry self-compatible variety Lapins was used in the artificial self-pollination experiment.The results showed that two self-compatible progenies from Lapins were identified as S4′S4′homozygous genotype which laid the foundation for breeding self-compatible varieties.

A study was conducted to explore the rooting molecular mechanisms of mutant Populusot mentosa carr cuttings.The P. tomentosa carr rooting inhibited and wild-type Populus tomentosa carr rooting induced cuttings as control group , respective-ly.The cutting proteins from Populus tomentosa carr, inhibition of mutant P.tomentosa carr and wild-type P.tomentosa carr rooting were extracted .A total of fourteen differentially expressed proteins were identified by two-dimensional difference gel electrophoresis , among which ten proteins were up-regulated and four proteins were down-regulated .By mass spectrometry and relational databases , above proteins were bark storage protein , chlorophyll a/b binding protein and 60S acidic riboso-mal protein P2.Presumably, these proteins were involved in the mutant P.tomentosa carr cutting adventitious root forma-tion and growth process .

Taking potted 'Populus wutunensis' and Populus ×euramericana cv.'N3930' as experimental materials,the changes of endogenous hormone in apoplast of poplar immature stem were determined by microdialysis technique and high performance liquid chromatography,under NaCl(0,200,300 mmol/L) stress.The results showed that under the NaCl stress,ABA content in two poplar apoplastic increased,while other hormones decreased.ABA accumulation under high concentration salt stress was greater than that under middle concentration salt stress.When under the same salt stress,Populus ×euramericana cv.'N3930' accumulated more ABA than 'Populus wutunensis' to resist the coercive environment;salt balance coefficient of 'Populus wutunensis' was less than that of Populus ×euramericana cv.'N3930'.CTK and IAA,CTK and GA,IAA and GA of the two poplar were significantly correlated.The results indicated that salt tolerance of 'Populus wutunensis' was stronger than that of Populus ×euramericana cv.'N3930'.

生物技术专业是生物学领域一个新兴的本科专业。大连民族学院隶属于国家民族事务委员会,是国家唯一设在东北和沿海开放地区、以工科和应用学科为主要特色的综合性民族高等学校。为了尽快适应民族地区生物技术应用型人才培养的需要,对民族院校特色生物技术专业的建设进行探讨:完善专业培养方案和教学大纲;强化师资队伍建设和培训;加强实验室和实习实训基地建设;加强课程和教材建设;开展教学法研究和改革;鼓励考研和积极开展国际化办学;加强教学管理和完善教学质量评估体系;加强学生职业规划指导。以上措施为民族院校生物技术专业的探索起到重要借鉴意义。

The apoplast dialysates from poplar trees were obtained using the microdialysis technique. To compare the salt tolerance of Populus×wutunensis and Populus×euramericana, the dynamics of their endogenous hormones were determined by high performance liquid chromatography and the difference in chlorophyll photosynthetic fluorescence parameters was analyzed under salt stress. The results showed that ABA level in P. ×wutunensis under the high-concentration salt stress for fifteenth days was 1.3 times higher than that under the normal condition, while it was 1.8 times higher in P. ×euramericana under salt stress. The Fv/Fm and ETR values in P.×euramericana were significantly lower than those in P. ×wutunensis, indicating that the photosynthetic system of P. ×euramericana was more severely affected. Furthermore, the salt balance coefficient of P. ×euramericana is obviously bigger than that of P. ×wutunensis, suggesting that under highconcentration salt stress the coordinative capacity of hormones in P. ×euramericana was decreased and its growth was more severely inhibited by stress than that in P. ×wutunensis. Together, our results suggest that P. ×wutunensis has higher salt tolerance than P. ×euramericana. Our approaches used in this study may be useful for studying the physiological mechanisms of salt tolerance in poplar apoplast and for selection and breeding salt tolerant varieties of Populus.

A dialyzate was obtained from the tender stems of living poplar (Populus wutunensis) by microdialysis (MD). Four kinds of endogenous hormones, namely, benzylamino purine, gibberellic acid, indole acetic acid, and abscisic acid, were then simultaneously determined by HPLC. The molecular weight cutoff (MWCO) of the MD probe was 30 kDa. The perfusion rate was 1 mu L/min, and the perfusion liquid was Millipore-Q water. HPLC was performed using an Inertsil ODS-SP column. The mobile phase comprised 60: 40 (v/v) methanol and water containing 0.2% phosphoric acid. The elution rate was 0.6 mL/min rate at 30 degrees C. The average recoveries of the four kinds of hormones ranged from 93% to 109%, with correlation coefficients greater than 0.998. The determinations of endogenous hormones in plants as real time, living, and online were realized by MD-HPLC. The cells and macromolecules were excluded by the MD probe so centrifugation or protein precipitation was not required prior to analysis. MD-HPLC is a highly sensitive and selective method for the simultaneous profiling and quantification of a wide variety of plant hormone groups. This method is convenient for studying the mechanism of plant hormones.

In this paper we investigated effects of apoplastic ion dynamic changes in the tender stems of Populus wutunenses and "P.simonii×P. euphratica"×P. sp. on gas exchange parameters under salt stress. The apoplastic ions were monitored by microdialysis and atomic absorption, and the gas exchange parameters were determined with a portable photosynthesis system. The net photosynthetic rates (Pn) of the two poplar cultivars all decreased with increasing salt-treated duration. The stomatal conductance (Gn) and intercellular CO2 concentration (Ci) of P.×wutunenses increased and then decreased, whereas its stomatal limitation (Ls) exhibited a contrary changing trend. The Gn and Ci of "P. simonii×P. euphratica"×P. sp. gradually reduced, whereas its Ls increased gradually. The results indicated that the photosynthetic inhibition of P.×wutunenses under the stress of 100 mmol·L-1 NaCl resulted from non-stomatal limitation and stomatal limitation successively, whereas that of "P. simonii×P. euphratica"×P. sp. resulted from stomatal limitation throughout the entire experiment. PnS of the two poplar cultivars were negatively correlated with Na+ concentration and Na+/K+ ratio significantly, however were positively correlated with K+ concentration extremely significantly. A multiple linear stepwise regression analysis was performed with Pn as the dependent variable, and Na+, K+, Ca2+ concentrations and Na+/K+ as the independent variables. Pn was only significantly correlated with Na+/K+ aomg those independent variables. P.×wutunenses was more salt-tolerant than "P. simonii×P. euphratica"×P. sp. under salt stress. The statistical equation showed that apoplastic ion contents in the tender stems of poplar cultivars were collinearly correlated with their photosynthesis performance under salt stress.

The apoplast and plant cells are inextricably linked,yet the response to drought stress within apoplast has rarely been reported.In this paper,the drought stress responses of apoplastic endogenous hormones in tender stems of three poplar species were studied by using MD-HPLC coupled technique.Four kinds of endogenous hormones in the apoplast of tender stems of living poplar which were dialyzed by microdialysis probe,i.e.benzylaminopurine(6-BA),gibberellic acid(GA 3),indole aceticacid(3-IAA),and abscisic acid(ABA),were then simultaneously determined by HPLC.The results show that drought stress has a significant effect on the content of endogenous hormones within the apoplast(P0.05).As the drought stress was intensified and lasting,the contents of GA 3,6-BA and 3-IAA obviously decreased while the content of ABA increased significantly(P0.01),meanwhile the contents of GA 3,6-BA,3-IAA and ABA has changed differently among poplar species.This paper has provided a new basis for study on physiological response mechanism to drought stress and it also provides a new method for the dynamically quantitative analysis of the apoplastic endogenous hormone in vivo.

Microdialysis is a sampling technique that can be employed to monitor biological events both in vivo and in vitro,it can be coupled with a variety of analytical instruments,can provide monitoring information for biological active substances changed with time and concentration in other aqueous environment or outside the cells dynamically in realtime.It is advantageous in fast,selective and sensitive analysis while preserving temporal information without affecting the growth of organisms.At the same time,the changes of analyte can be detected immediately in external environment.Furthermore,microdialysis samples without pretreatment,which are coupled with high-precise analytical systems,will realize truly real-time,online and cheap tracking detection.Although microdialysis sampling focusing on intercellular matrix has been applied in animals and human,it has not been extensively employed to detect various material changes in plant apoplast.So microdialysis sampling technique can overcome the bottleneck of previous research on plants.An overview of microdialysis system about principle,probe,membrane and parameters,furthermore sampling for plants and analytical methods employed for online analysis,including gas chromatography(GC),high performance liquid chromatography(HPLC),capillary electrophoresis(CE),and so on,were reviewed.