读书报告5-增二氧化碳浓度增氮供应对减少一枝黄花属叶片疾病和光合作用的影响课件.ppt

1、Elevated CO2 and increased N supply reduce leaf disease and related photosynthetic impacts on Solidago rigida提高提高CO2浓度和增加浓度和增加N供应对减少一枝黄花属供应对减少一枝黄花属叶片疾病和光合作用的影响叶片疾病和光合作用的影响 Joachim Strengbom Peter B.ReichOecologia(2006)149:519525 期刊介绍生态学（Oecologia）,国际生态学会出版，在ISI科技引文生态学类期刊中位于前列，此刊物主要登载关于生理生态学、种群生态学、植物

2、动物相互关系、生态系统生态学、群落生态学、生态保护方面的文章，也刊登一些评论性文章及生态学研究方法进展方面的学术论文。主编：J.R.Ehleringer(Salt Lake City),C.H.Peterson(Morehead City),M.Schaefer(Gottingen),E.D.Schulze(Bayreuth)作者介绍 My gains and Thinking Introduction Discussion Results Materials and methodsOUTLINEIntroduction12Why?Evaluated whether leaf spot dis

3、ease and related effects on photosynthesis are influenced by increased nitrogen(N)input and elevated atmospheric CO2 concentration(CO2).Introduction评估增加氮供给和提高大气CO2浓度对叶斑病和光合作用的影响 Pathogenic fungi may have a profound impact on plant communities by influencing various ecosystem processes such as primar

4、y productivity and plant community structure.引起疾病的真菌在生态系统进程中对植物群落有深刻的影响，比如，主要生产力和植物群落结构 Human related activities are known to increase atmospheric CO2 concentration CO2and the rate of nitrogen(N)deposition,which independently or in combination are likely to have large effects on structure and functi

5、on in terrestrial plant communities.与人类相关的活动被认为是大气CO2 浓度的增加和N素储存速率的增加，不论是其单独的或是相联合的活动，都可能很大程度上影响到地球植物群落的结构和功能Introduction Increased knowledge of how interactions between plants and pathogens may vary with changes in these abiotic global change factors may be required to accurately predict their effe

6、cts on plant ecosystem functioning and structure in the future.增加一些了解，在全球非生命因素改变下植物和病原体是如何进行相互作用的，也许可以精确的预测将来它们对植物生态系统功能和结构的影响。Although it is well established that leaf diseases reduce the photosynthetic capacity of plants and that elevated CO2 and increased N input may influence the photosynthetic

7、rates of plants.尽管叶片疾病会减少植物光合作用能力，但是提高CO2 浓度和增加N的输入会影响植物的光合速率。Introduction we do not know of any studies that have examined how negative effects on photosynthetic rates from pathogenic fungi are affected by simultaneous increase in CO2 and N supply.我们不知道有哪一个研究调查过同时存在增加CO2 浓度和供应N的情况下引起疾病的真菌对光合速率有怎样的消

8、极影响IntroductionIntroductionfungico2NWe examined disease incidence and photosynthetic rate of Solidago rigida grown in monoculture under ambient or elevated(560mol/mol-1)CO2 and ambient or elevated(+4 g N m-2year-1)N conditions in a field experiment in Minnesota,USA.我们检测了美国明尼苏达州生长在环境单作下的一枝黄花属和生长在增加CO

9、2浓度和提高N的条件下一枝黄花属的发病率和光合速率。Study site and experimental design Disease incidence and severity Gas exchange and relative photosynthetic rate Plant biomass,N content,and chemical analyses Statistical analysesMaterials and methodsMaterials and methodsBioCON:Biodiversity,Carbon dioxide,and Nitrogen effect

10、s on ecosystem functioning http:/www.lter.umn.edu/biocon/Materials and methodsCO2(560mol/mol-1)CO2(368mol/mol-1)N：fertilized with NH4NO3at a rate of 4gN/m-2year-1.experimental design10m In the present study,we used a subset of plots(monocultures of S.rigida)within this experiment.在这次研究中，我们用单作的一枝黄花属作

11、为本次试验小区的子集。Materials and methodsFor the S.rigida plots,each treatment is replicated twice(n=2,eight plots in total)对于小区来说，每一个处理设两次重复，一共八个小区。Disease incidence and severity In mid-June 2003,we estimated the disease incidence by scoring leaves of S.rigida for leaf spot diseases in each study plot。2003年

12、6月中旬我们通过对一枝黄花属具有划痕叶片的叶斑病的了解在每一个小区内评估了疾病的发生率。Materials and methods We used the UTHSCSA Image Tool program(version 3.00)to manually digitalize the leaf area and the area with visual lesions.我们用UTHSCSA图像处理分析工具对叶片区域和可以看见的有损伤的区域进行处理。Materials and methods The majority of the lesions on diseased leaves wer

13、e due to infection by Cercospora sp.在生病的叶上损伤的多数部分是由尾孢属影响的。On a few leaves,we also found a few conidia of Septoria sp.,indicating that this pathogen was also present.在少数的叶片上，我们也发现了少量的壳针孢属的分生孢子，这标志着这些病原体也出现。Materials and methods Gas exchange and relative photosynthetic rate After scoring the plot leve

14、l of disease,we marked and took digital images of a number of asymptomatic and diseased leaves in each plot.我们在每一个小区中对划痕感病的和无病症的叶片进行数字图像处理。Materials and methods We used these leaves to measure the in situ rates of leaf net photosynthesis by using CIRAS-1 portable infrared gas exchange systems(PP Sys

15、tems,Hitchin,UK)operated in open configuration with controlled temperature,CO2 concentration,and vapor pressure.我们通过手提式红外气体交换仪对原地的叶片进行净光合速率的测定，在布局的地方控制好温度，CO2浓度和水蒸汽压。Materials and methods The average net photosynthesis over the three measurements was used as an estimate of the photosynthetic rate fo

16、r an individual leaf。对所取的叶片，我们对其所测的净光合速率均测定三次以上。Materials and methodsMaterials and methods生物量 N含量和化学分析 Statistical analyses To analyze for differences in disease severity and incidence between the treatments we used ANOVA.(感病的严重性和发生率)Differences in biomass accumulation（积累）,N accumulation and N and C

17、 concentration（N和C的浓度）were analyzed by ANOVA.Materials and methods We also used ANOVA with the absolute photosynthetic（完全光合速率）rate for each leaf measured as dependent variable and disease status(symptomatic or asymtomatic)of the leaf,levels CO2 and N as factors.Materials and methods Fig.1 Abundance

18、of foliar disease on S.rigida showing the average proportion of diseased leaves(disease incidence)and the average proportion of leaf area diseased(disease severity).Plants were grown under ambient or elevated CO2 and N supply or a combination of both.The majority of the lesions on diseased leaves we

19、re due to infection by Cercospora sp.On a few leaves,we also found a few conidia of Septoria sp.Error bars represent SE （感病的比例）Results S.rigida grown under elevated CO2(ANOVA:F1,2=594.43,P=0.002)and increased N supply(F1,2=24.89,P=0.038)showed lower disease incidence(proportion diseased leaves)than

20、plants grown under ambient conditions。增加CO2 浓度和N供应的要比环境发病率低Results Disease incidence was on average more than twice as high under ambient as under elevated CO2,whereas under increased N sup-ply the incidence was about 30%lower compared to ambient conditions。环境CO2浓度的发病率比增加CO2浓度的发病率高2倍多。We found no in

21、teraction between the two treatments(F1,2=0.947,P=0.433),and the effects of CO2 and N on disease incidence were similar at both levels of the other treatment。（相似性）Results Fig.2 Nitrogen concentration in 2003 in aboveground parts of S.rigida grown under ambient or elevated CO2 and N conditions or a c

22、ombination of both.Error bars represent+-SEResults The N addition treatment had a marginally significant effect on tissue N(ANOVA:F1,4=4.71,P=0.096),and elevated CO2 resulted in significantly lower(by13%)tissue N(F1,4=16.04,P=0.016).增加N供应条件下的发病率要比环境条件下的发病率大约低13%。Results a The N fertilization treatme

23、nt was 4gN m2 year-1 In ANOVA analyses of CO2,N,and year and their interactions,N treatment was the only significant(P 0.05)effect on biomass(F1,8=10.18,P=0.013)and total N(F1,8=19.29,P=0.002).在方差分析CO2与N的相互作用中，只有N处理显著影响生物量和总N Overall,the absolute photosynthetic rate was lower on diseased leaves than

24、 on asymptomatic leaves(ANOVA:F1,76=37.80,P0.001).总体上感病的叶片净光合速率要比无症状的低。Since the measurements were taken on asymptomatic areas of the leaves regardless of disease status,our data show that the eV ect of the foliar disease extends beyond the visual area of the lesions.通过对感病叶片无症状的区域的测量，我们的数据显示叶疾病的影响延伸

25、到了被损坏的叶片之外 This pattern was consistent across all treatments and asymptomatic leaf tissue on diseased leaves had on average 53%lower absolute photosynthetic rate than non-diseased leaves。这种情况一直波及所有的处理和感病叶片上无症状的叶片组织，其光合速率比没有感病的叶片低，是其的53%When comparing the relative photosynthetic rate neither CO2(ANCO

26、VA:F1,47=0.024,P=0.878)nor N input(F1,47=1.10,P=0.299)had any effect(Fig.4).This means that we found no support for the hypothesis that elevated CO2 or increased N input would enable plants to compensate for lost leaf tissue due to foliar diseases by higher photosynthetic rates in asymptomatic parts of the leaves.看完本篇文献的感言：做实验一定要严谨，每时每刻都要有疑问的习惯，相信自己的实验结果，不是每一个假说都是正确的。我觉得还可以根据每棵植物中的氮含量的多少结合光合速率做出进一步的分析。My gains and Thinking 谢谢 请各位老师同学批评指正！Materials and methods