Bicentenary homage to Dr Jan Ingen-Housz,MD (1730–1799), pioneer of photosynthesis research

On September 7, 1999, the 200th anniversary of the death of Dr Jan Ingen-Housz was commemorated by ceremonies in Calne, England. Ingen-Housz discovered the action of light in photosynthesis in 1779, following Joseph Priestley's demonstration that green plants had the capacity to produce oxygen. Priestley's claim for priority in discovering the light requirement of photosynthesis is examined. This revised version was published online in June 2006 with corrections to the Cover Date.     

On the requirement of minimum number of four versus eight quanta of light for the evolution of one molecule of oxygen in photosynthesis: A historical note

A bitter controversy had existed as to the minimum number of quanta required for the evolution of one molecule of oxygen in photosynthesis: Otto Warburg had insisted since 1923 that this value was 3–4, whereas Robert Emerson and others continued to obtain a value of 8–12 since the 1940s. It is shown in this letter that the 1931 Nobel-laureate of Physiology & Medicine Otto Warburg published, in his last and final paper, just before his death in 1970, a measured minimum quantum requirement of oxygen evolution of 12 at the lowest intensities of light he used. Although using his theory on photolyte, Warburg calculated a value of 3–4 for the quantum requirement, this is the first confirmation by Warburg of the higher measured quantum requirement. However, it has remained unknown to most investigators. It is expected that this information will be of general interest not only to those interested in the history and research on photosynthesis, but to the entire sci entific community, especially the writers of text books in biology, biochemistry and biophysics.     

History of the word photosynthesis and evolution of its definition

In 1893, Charles Barnes (1858–1910) proposed that the biological process for ‘synthesis of complex carbon compounds out of carbonic acid, in the presence of chlorophyll, under the influence of light’ should be designated as either ‘photosyntax’ or ‘photosynthesis.’ He preferred the word ‘photosyntax,’ but ‘photosynthesis’ came into common usage as the term of choice. Later discovery of anoxygenic photosynthetic bacteria and photophosphorylation necessitated redefinition of the term. This essay examines the history of changes in the meaning of photosynthesis. This revised version was published online in June 2006 with corrections to the Cover Date.     

The legacy of Hans Molisch (1856–1937), photosynthesis savant

Hans Molisch (1856–1937) was an exceptionally gifted and productive researcher who had broad interests in plant biology, physiology and biochemistry. In addition, he pioneered in isolating a number of species of purple photosynthetic bacteria in pure culture (including Rhodobacter capsulatus), which facilitated his discovery of basic aspects of bacterial photosynthesis. Molisch demonstrated conclusively that molecular oxygen is not produced by photosynthetic bacteria, and discovered the photoheterotrophic growth mode. The range of Molisch's research accomplishments was impressive, and he emerges as a major figure in the history of photosynthesis research. This essay reviews the numerous research contributions made by Molisch, particularly in regard to advancing knowledge of the several forms of photosynthetic metabolism. An English translation of his 1914 paper on the photosynthetic creation of visual images on leaves is included as an Appendix.     

From Charles Darwin's botanical country-house studies to modern plant biology

As a student of theology at Cambridge University, Charles Darwin (1809–1882) attended the lectures of the botanist John S. Henslow (1796–1861). This instruction provided the basis for his life-long interest in plants as well as the species question. This was a major reason why in his book On the Origin of Species , which was published 150 years ago, Darwin explained his metaphorical phrase 'struggle for life' with respect to animals and plants. In this article, we review Darwin's botanical work with reference to the following topics: the struggle for existence in the vegetable kingdom with respect to the phytochrome-mediated shade avoidance response; the biology of flowers and Darwin's plant–insect co-evolution hypothesis; climbing plants and the discovery of action potentials; the power of movement in plants and Darwin's conflict with the German plant physiologist Julius Sachs; and light perception by growing grass coleoptiles with reference to the phototropins. Finally, we describe the establishment of the scientific discipline of Plant Biology that took place in the USA 80 years ago, and define this area of research with respect to Darwin's work on botany and the physiology of higher plants.     

Assimilate Transport and Partitioning in Plants: Approaches,Methods, and Facets of Research

This review, dedicated to the 100th anniversary of A.L. Kursanov's date of birth, considers the development of phloem transport studies since his book, Assimilate Transport in the Plant, was published in 1976. This book and several other fundamental publications on phloem structure and functions basically shaped this physiological issue; as a result, several international meetings by scientists working in the area were induced, and the proceedings of these meetings were published at regular intervals. Six conferences have been held to date, and six corresponding collections of papers have been published and are reviewed here along with other experimental communications and reviews. This review considers the following topics: (1) the phloem structure and the ultrastructure of specialized phloem cells, (2) the physiological functions of phloem and their regulation, (3) photosynthesis and phloem loading with assimilates, (4) phloem unloading and the related processes of plant growth and development, (5) the mechanisms of sugar and amino acid transport, (6) the levels of transport, (7) transport compartments; (8) xylem–phloem and symplast–apoplast communication; (9) phloem transport vs. the integral plant physiology, (10) transport of xenobiotics, and (11) the trophic transport networks in symbionts.     

The recovery of photosynthesis in tomato subsequent to chilling exposure

The overall success of a plant in coping with low temperature sensitivity of photosynthesis is dependent not only on the maximum extent of inhibition suffered for a given time of low temperature exposure but also on the persistence of the inhibition after normal growth temperatures are restored. Thus the capacity of recovery and the speed with which a plant can recover from the effects of chilling exposure are important parameters in determining how devastating the chilling event will be on season-long growth and yields. We have studied the recovery of CO₂-saturated photosynthesis from the injury caused by exposing intact tomato plants (Lycopersicon esculentum Mill. cv. Floramerica) or detached tomato leaves to a temperature of 1°C in the dark for varying periods of time. We found that net photosynthesis was fully recovered within 12 h after returning the plants to 25°C in the dark, even after chilling exposures as long as 45 h. This was true for intact plants as well as for detached leaves that were supplied with water. When chilling took place in the light (4°C, 1000 E · m^-2 · s^-1, PAR) inhibition of photosynthesis was more severe and appeared more quickly and the recovery was slower and incomplete. A 12 h chilling exposure in the light resulted in injury to net photosynthesis that was not fully recovered even after 50 h. Chilling damage to photosynthesis developing in the light was distinguished from chilling in the dark by the decreased photosynthetic quantum yield. Not only did high intensity illumination enhance chilling damage of photosynthesis but bright light subsequent to the chilling exposure also delayed the recovery of photosynthesis. At none of the three ambient CO₂ concentrations investigated (300, 1500 and 5000 1.1^-1) did the recovery of photosynthesis depend on stomatal conductance.     

Sixty years in algal physiology and photosynthesis

This personal perspective records research experiences in chemistry and biology at four German universities, two before and two after World War II. The research themes came from cytophysiology of green unicellular algae, in particular their photosynthesis. The function of inorganic ions in photosynthesis and dark respiration was investigated at different degrees of specific mineral stress (deficiencies), and the kinetics of recovery followed after the addition of the missing element. Two types of recovery of photosynthesis were observed: indirect restitution via growth processes and immediate normalisation. From the latter case (K⁺, phosphate, Mn⁺⁺) the effect of manganese was emphasized as its role in photosynthetic O₂ evolution became established during our research. Other themes of our group, with some bearing on photosynthesis were: synchronization of cell growth by light-dark change and effects of blue (vs. red) light on the composition of green cells. Some experiences in connection with algal mass cultures are included. Discussion of several editorial projects shows how photosynthesis, as an orginally separated field of plant biochemistry and biophysics, became included into general cell physiology and even ecophysiology of green plants. The paper contains an appreciation of the authors' main mentor Kurt Noack (1888–1963) and of Ernst Georg Pringsheim (1881–1970), founder of experimental phycology.Written at the invitation of Govindjee.     

A list of personal perspectives with selected quotations,along with lists of tributes,historical notes,Nobel and Kettering awards related to photosynthesis

The history of photosynthesis research can be found in original papers and books. However, a special history is available from the prefatory chapters and the personal perspectives of various researchers who published them in several journals over the last 40 years. We have compiled a list of such perspectives published since 1964. Selection is not easy, especially of authors who were not directly engaged in photosynthesis research; some are included for their special insights related to central issues in the study of photosynthesis. Our journal, Photosynthesis Research, contains other valuable historic data in the occasional tributes, obituaries and historical notes, that have been published. Lists of these items are included. This article ends by listing the Nobel prizes related to photosynthesis and the Kettering Awards for Excellence in Photosynthesis Research. Wherever possible, a web page address is provided. The web page addresses have been taken from the article `Photosynthesis and the Web: 2001' by Larry Orr and Govindjee, available at http://www.life.uiuc.edu/govindjee/photoweb and at http://photoscience.la.asu.edu/photosyn/ photoweb/default.html. ‘When I find a bit of leisure I trifle with my papers. This is one of the lesser frailities. – Horace, Satires I, IV. This revised version was published online in June 2006 with corrections to the Cover Date.     

A biographical sketch of Charles F. Yocum: “It's the biochemistry, stupid”

Charles F. Yocum has been a leader in the applications of biochemical techniques to the resolution and reconstitution of Photosystem II. His formal science education began as an undergraduate in biochemistry at Iowa State University and continued with graduate work in photosynthesis, first at the Illinois Institute of Technology and later at Indiana University. Following postdoctoral work at Cornell University, he joined the faculty of the University of Michigan where he has remained throughout his academic career. Charlie's contributions to a biochemical understanding of photosynthesis, particularly Photosystem II have been considerable, but most notably include his initial isolation of the first highly active oxygen-evolving particle from higher plant chloroplasts, the well-known and widely utilized `BBY particles'. In the aftermath of that isolation, Charlie's research further resolved these particles into ever finer and simpler, but active, Photosystem II complexes. In addition, Charlie's research has provided significant insight into the roles of both Cl⁻ and Ca²⁺ as required cofactors in photosynthetic oxygen evolution. This revised version was published online in June 2006 with corrections to the Cover Date.     

30-year progress of membrane transport in plants

In the past 30 years enormous progress was made in plant membrane biology and transport physiology, a fact reflected in the appearance of textbooks. The first book dedicated to ‘Membrane Transport in Plants’ was published on the occasion of the ‘International Workshop on Membrane Transport in Plants’ held at the Nuclear Research Center, Jülich, Germany [Zimmermann and Dainty (eds) 1974] and was followed in 1976 by a related volume ‘Transport in plants II’ in the ‘Encyclopedia of plant physiology’ [Lüttge and Pitman (eds) 1976]. A broad spectrum of topics including thermodynamics of transport processes, water relations, primary reactions of photosynthesis, as well as more conventional aspects of membrane transport was presented. The aim of the editors of the first book was to bring advanced thermodynamical concepts to the attention of biologists and to show physical chemists and biophysicist what the more complex biological systems were like. To bundle known data on membrane transport in plants and relevant fields for mutual understanding, interdisciplinary research and clarification of problems were considered highly important for further progress in this scientific area of plant physiology. The present review will critically evaluate the progress in research in membrane transport in plants that was achieved during the past. How did ‘Membrane Transport in Plants’ progress within the 30 years between the publication of the first book about this topic (Zimmermann and Dainty 1974), a recent one with the same title (Blatt 2004), and today?     

A new principle photosynthesis capacity biosensor based on quantitative measurement of delayed fluorescence in vivo

Delayed fluorescence (DF) is an excellent marker for evaluating plant photosynthesis. Compared with common methods for measuring the photosynthesis rate based on consumption of CO₂, DF technique can quantify the plant photosynthesis capacity more accurately and faster under its physiological status with less interference from the environment. We previously reported a method for measuring photosynthesis using DF of chloroplast [Wang, C.L., Xing, D., Chen, Q., 2004. Biosens. Bioelectron. 20, 454–459]. In the study, a novel fast and portable photosynthesis capacity biosensor system was developed, which was composed of light-emitting diode lattice as excitation light source, Channel Photomultiplier DC-Module to achieve DF, single-chip microcomputer as control center, hermetic dark sample chamber, battery power supply and CO₂, humidity and temperature controller. Compared with our previous work, the system was portable and can directly measure plant photosynthesis capacity in vivo in less than 10 s. A database in the software to carry out data acquisition and processing was developed to translate maximal DF intensity to net photosynthesis rate (Pn). In addition, local-control and remote-control mode can be chosen in the system. To demonstrate the utility of the system, it was applied to evaluate maximum Pn of four different plant species samples (Queen Rape Myrtle (var. rubra), soybean (Lu Hei No. 1), maize (Jin Dan No. 39) and rice (Jing Dao No. 21)) in field. The results were compared with that using commercial photosynthesis system LI-6400 and the uncertainty was less than ±5%. The new principle of photosynthesis measurement is a challenge and breakthrough to conventional method of gas exchange and may be a potential technique of next generation photosynthesis measurement.     

Interaction of drought and high temperature on photosynthesis and grain-filling of wheat

Drought and high temperature often occur simultaneously, but their effects on crops are usually investigated individually. Our objective was to compare effects of drought, high temperature, and their interactions on photosynthesis and grain-growth of wheat (Triticum aestivum L.). Plants (cv. Len) were grown uniformly in well-watered soil at 25/20 ± 2 °C day/night until anthesis, when they were subjected to regimes of no drought (soil at field capacity) and drought (plant water potential of –.0 to –2.4 MPa) at 15/10, 25/20, and 35/30 °C in controlled environments until physiological maturity. Drought decreased photosynthesis, stomatal conductance, viable leaf area, shoot and grain mass, and weight and soluble sugar content of kernels but increased plant water-use efficiency. High temperature hastened the decline in photosynthesis and leaf area, decreased shoot and grain mass as well as weight and sugar content of kernels, and reduced water-use efficiency. Interactions between the two stresses were pronounced, and consequences of drought on all physiological parameters were more severe at high temperature than low temperature. The synergistic interactions indicated that productivity of wheat is reduced considerably more by the combined stresses than by either stress alone, and that much of the effect is on photosynthetic processes.     

Celebrating the millennium – historical highlights of photosynthesis research,Part 2

This paper is an introduction to Part 2 of our celebrations of the historical highlights of photosynthesis research. Part 1 was published in October 2002 as Volume 73 of Photosynthesis Research. After a brief introduction, we recognize two giants in the field: Cornelis B. van Niel (for anoxygenic photosynthesis), and Robert Hill (for oxygenic photosynthesis). This is followed by recognition of a 1960 book by Hans Gaffron, and a multi-authored book edited by W. Ruhland and André Pirson, and inclusion in the appendix of a list of selected books. Our celebration is enhanced by the inclusion of beautiful paintings of cells by Antoinette Ryter. After introducing all the historical papers contained in this volume, we honor Louis N. M. Duysens, one of the greatest biophysicists of our time, and finally we dedicate this volume to a great scientist, humanist and peacemaker: Eugene I. Rabinowitch. [12pt] 'Annihilating all that is made To a green thought in a green shade' – Andrew Marvell (1621–1678), The Garden (1681) This revised version was published online in August 2006 with corrections to the Cover Date.     

Gustav Senn(1875–1945): The pioneer of chloroplast movement research

Gustav Senn analyzed for the first time light-induced movement and arrangement of chloroplasts. Using many plant species he performed physiological analyses of chloroplast migration in response to exte...     

光合作用对光和CO2响应模型的研究进展

光合作用对光和CO₂响应模型是研究植物生理和植物生态学的重要工具, 可为植物光合特性对主要环境因子的响应提供科学依据。该文综述了当前光合作用对光和CO₂响应模型的研究进展和存在的问题, 并在此基础上探讨了这些模型的可能发展趋势。光合作用涉及光能的吸收、能量转换、电子传递、ATP合成、CO₂固定等一系列复杂的物理和化学反应过程。光合作用由原初反应、同化力形成和碳同化3个基本过程构成, 任一个过程均可对光合作用速率产生直接的影响。光合作用对光响应模型只涉及光能的转换, 而光合作用的生化模型包含了同化力形成和碳同化这两个基本过程。把光合作用的原初反应, 即把参与光能吸收、传递和转换的捕光色素分子的物理参数(如捕光色素分子数、捕光色素分子光能吸收截面、捕光色素分子处于激发态的平均寿命等)结合到生化模型中, 可能是今后光合作用对光响应机理模型的发展方向。     

Crassulacean acid metabolism photosynthesis: `working the night shift'

Crassulacean acid metabolism (CAM) can be traced from Roman times through persons who noted a morning acid taste of some common house plants. From India in 1815, Benjamin-Heyne described a `daily acid taste cycle' with some succulent garden plants. Recent work has shown that the nocturnally formed acid is decarboxylated during the day to become the CO₂ for photosynthesis. Thus, CAM photosynthesis extends over a 24-hour day using several daily interlocking cycles. To understand CAM photosynthesis, several landmark discoveries were made at the following times: daily reciprocal acid and carbohydrate cycles were found during 1870 to 1887; their precise identification, as malic acid and starch, and accurate quantification occurred from 1940 to 1954; diffusive gas resistance methods were introduced in the early 1960s that led to understanding the powerful stomatal control of daily gas exchanges; C₄ photosynthesis in two different types of cells was discovered from 1965 to ∼1974 and the resultant information was used to elucidate the day and night portions of CAM photosynthesis in one cell; and exceptionally high internal green tissue CO₂ levels, 0.2 to 2.5%, upon the daytime decarboxylation of malic acid, were discovered in 1979. These discoveries then were combined with related information from C₃ and C₄ photosynthesis, carbon biochemistry, cellular anatomy, and ecological physiology. Therefore by ∼1980, CAM photosynthesis finally was rigorously outlined. In a nutshell, 24-hour CAM occurs by phosphoenol pyruvate (PEP) carboxylase fixing CO₂(HCO₃ ⁻) over the night to form malic acid that is stored in plant cell vacuoles. While stomata are tightly closed the following day, malic acid is decarboxylated releasing CO₂ for C₃ photosynthesis via ribulose bisphosphate carboxylase oxygenase (Rubisco). The CO₂ acceptor, PEP, is formed via glycolysis at night from starch or other stored carbohydrates and after decarboxylation the three carbons are restored each day. In mid to late afternoon the stomata can open and mostly C₃ photosynthesis occurs until darkness. CAM photo-synthesis can be both inducible and constitutive and is known in 33 families with an estimated 15 to 20 000 species. CAM plants express the most plastic and tenacious photosynthesis known in that they can switch photosynthesis pathways and they can live and conduct photosynthesis for years even in the virtual absence of external H₂O and CO₂, i.e., CAM tenaciously protects its photosynthesis from both H₂O and CO₂ stresses. This revised version was published online in August 2006 with corrections to the Cover Date.