Free Essay

Limitations of Photosynthate Sources and Sinks at Time of Grain Filling in an Australian Hard Wheat Cultivar

In: Science

Submitted By chris1234
Words 910
Pages 4
Limitations of photosynthate sources and sinks at time of grain filling in an Australian hard wheat cultivar.

Introduction
An estimated two-thirds of the worlds population depend on wheat in their diet (Alam et al. 2008). In
Australia, wheat (Tritium sp.) alone had an export value of $5.5 billion in 2010-2011 and is therewith the most valuable grain crop for Australia (ABARES 2011). To remain competitive as a wheat exporter in future, improving wheat yields seems imperative, hence improving the understanding of physiological processes during different plant-growth phases, may help to find and select specific factors that limit grain yield and ultimately help to breed better performing cultivars (Richards 1996). One area of research is dedicated to the better understanding of the limits of sources (plant organs such as leaves that produce and export photosynthates) and sinks (all plant parts such as roots or seeds that mostly store those photosynthates) after anthesis or during grain filling (Bingham et al. 2009; Fischer et al. 1977). Grain filling is a complex process involving formation, translocation, partitioning and accumulation of photosynthates in interaction with the sink-source capacities and preferences under different environments and growth stages (Felekari et al. 2014).
Past research indicated that the wheat grain as a sink is limited by the capacity of its sources during grain filling (Ma et al. 1990; Alam et al. 2008), however data had a high variance reflecting the different genotypes used and the diversity of experimental techniques and the wide spectrum of conditions these studies have been undertaken (Bowring 2010). Although the harvest index (ratio of yield to total above ground biomass) has increased over the years due to plant breeding (Taiz et al. 2015) the continuous goal of the industry is to further increases production values, also by increasing plant physiology knowledge and in particular the partitioning (amount distributed into different sinks) of photosynthates. The aim of this experiment was to identify source-sink limitations of an Australian wheat cultivar and test the hypothesis that, at stage of grain filling, sources are in fact the dominant limitation.

Page 1


Conclusion
The results of the tested wheat cultivar T. aestivum cv. Meering, which was tested post anthesis, was indeed limited by its photosynthate producing sources which confirms this common hypothesis. The spike of this cultivar showed a high source strength which was equally important as a source as FL1 and FL2 combined.
However as highlighted by Bowring (2010) the physiological processes are complex and data of past and current research is highly variable, hence for future research it would be prudent to include genotype, season and climate conditions into each analysis so breeders are able to narrow down common factors.

References
ABARES (2011) ‘Agricultural commodity statistics 2011’ (Department of Agriculture, Fisheries and
Forestry: Canberra, Australia).
Alam M, Rahman A, Nesa M, Khan S, Siddquie N (2008) Effect of source and/or sink restriction on the grain yield in wheat. Journal of Applied Sciences Research 4, 258- 261.
Araus JL, Brown HR, Febrero A, Bort J, Serret MD (1993) Ear photosynthesis, carbon isotope discrimination and the contribution of respiratory CO2 to differences in grain mass in durum wheat.
Plant, Cell and Environment 16, 383-392.
Bingham IJ, Walters DR, Foulkes MJ, Paveley ND (2009) Crop traits and the tolerance of wheat and barley to foliar disease. Annals of Applied Biology 154, 159-173
BOT2ILP Subject Handbook and guide to practical classes (2015) Pages 19-28. La Trobe University.
Department of Botany
Bowring AD (2010) Post-Anthesis Contribution of Leaves and Stem to Wheat Yield in the Northern
Cropping Region of New South Wales, Thesis, University of New England.
Cruz-Aguado JA, Reyers F, Rodes R, Perez I, Dorado M (1999) Effect of source-to-sink ratio on partitioning of dry matter and 14C-photoassimilates in wheat during grain filling. Annals of Botany 83, 655-665.
Evans LT, Wardlaw IF (1996) Wheat. In ‘Photoassimilate distribution in plants and crops. Source-sink relationships’. pp. 501-518 (Marcel Dekker Inc: New York, USA).

Page 2


Felekari H, Ghobadi ME, Ghobadi M, Hornamand SJ, Saeidi M (2014) The effect of post anthesis source and sink limitations in wheat cultivars under moderate condition. International Journal of Biosciences,
5, 52-59.
Fischer RA, Aguilar I, Laing DR (1977) Post-anthesis sink size in a high- yielding dwarf wheat: yield response to grain number. Australian Journal of Agricultural Research 28, 165-175.
Fischer RA, HilleRisLambers D (1978) Effect of environment and cultivar on source limitation to grain weight in wheat. Australian Journal of Agricultural Research 29, 443-458.
Fischer RA (2008) The importance of grain or kernel number in wheat: A reply to Sinclair and Jamieson.
Field Crops Research 105, 15-21.
Koshkin EI, Tararina VV (1989) Yield and source-sink relations of spring wheat cultivars. Field Crops
Research 22, 297–306.
Ledent JF, Stoy V (1985) Responses to reduction in kernel number or to defoliation in collections of winter wheats. Agronomie 5, 499–504.
Ma YZ, Mackown CT, Sanford DV, Van SD (1990) Sink manipulation in wheat: compensatory changes in kernel size. Crop Sci., 30, 1099-1105
Richards, RA (1996) Increasing the yield potential of wheat: manipulating sources and sinks. In ‘Increasing yield potential in wheat: breaking the barriers’ pp. 134-149, proceedings of a workshop held in Ciudad
Obregón, Sonora, Mexico. CIMMYT.
Taiz L, Zeiger E, Moller IM, Murphy A (2015) ‘Plant Physiology and Development’ 6th Edn. (Sinauer
Associates Inc: Sunderland, Massachusetts, United States)

Page 3
…...

Similar Documents

Premium Essay

Hard Times by Dickens

...‘Hard times’ is a dawdling but captivating novel by Charles Dickens, first published in 1854. The book is a state-of-the-nation novel, which aimed to highlight the social and economic pressures that some people were experiencing. Unlike other such writings at the time, the novel is unusual in that it is not set in London (as was also Dickens' usual wont), but in the fictitious Victorian industrial town of Coke town, often claimed to be based on Preston. In ‘Hard Times’ Dickens shows his dislike for education in the Victorian age. He shows his dislike in many different ways through out the novel. Some examples of these are through Mr. M Gradgrind, the Schoolroom and also through the meaning of names. Dickens describes Mr. Gradgrind as a cold, machine like character. The only thing he taught was “Facts, facts and more facts”. Dickens uses Mr. M Gradgrind in this way to put across his message of how Young children are treated in the Victorian education system. In Hard times Dickens uses the meaning of names to describe how the Characters act and to get his point across. The name “Mr. M Choakumchild” Suggests that If the child does not do what do what they are told them he would Garrote them. Also the Name of the other Hard, Mean teacher “Mr. Gradgrind” Implies to the reader that the teacher will crush the student in to the ground if they do not do what they are told. Also, Dickens uses the setting of the School room to portray a certain message. He describes the Classroom......

Words: 414 - Pages: 2

Premium Essay

Hard Times: the Education System

...How does Dickens present the education system in hard Times?   Words: | Submitted: Thu Mar 24 2005   ... Not even a sense of fancy and imagination. They were educated to get the basics of life because they were going to be pushed into the outside world at a very young age of 12 and above or even below. At the end of the day, the education was worthless because most of the children died in the workhouse. Dickens used Hard Times to criticise the society for failing so many of its children. Dickens argues against a mode of factory style, grad-grinding production that exterminates the fun out of life. He believes that education should not be a thing of going through volumes of head-breaking questions and being put through an immense variety of paces. Hard Times not only suggests that fancy is as important as fact, but it continually calls into question the difference between fact and fancy. Dickens suggests that what constitutes so-called fact is a matter... How does Dickens present his views on education in ‘hard times’?   Words: | Submitted: Mon Jun 06 2005.   He is shown as lifeless and colorless, 'the boy was so light-eyed and light-haired that the self-same rays appeared to draw out of him what little color he ever possessed.' This gives the effect that he has been drained of life and everything else but facts. When asked, Blitzer describes a Horse as a 'Quadruped' and 'graminivorous' and gives endless facts about the animal. Although this description is......

Words: 622 - Pages: 3

Premium Essay

Hard Times Theme Analysis

...Hard Times |Theme Analysis | | | | | | | |[pic][pic][pic][pic][pic] | | | |Head versus Heart | |Hard Times shows the inadequacy of an approach to life that emphasizes only the human intellect at | |the expense of the imagination and the heart. The character who most embodies the false approach is | |Thomas Gradgrind. Gradgrind worships facts and figures and prides himself on being very practical. He| |thinks that the only things valuable in life are those that can be objectively measured. He believes | |that human behavior can be shaped for the better by the rational application of practical knowledge. | |Gradgrind refuses to accept the validity of "fancy" or imagination; only practical things matter, and| |he puts his faith in abstract theories rather than direct observation of how real people behave, and | |what their real......

Words: 1053 - Pages: 5

Premium Essay

Hard Times

...The industrial revolution was a time of great technological changes. It revolutionised everything, from the way people lived to where they worked, but what society often overlooked was how ordinary people went through their day to day lives. In the book ‘Hard Times’, Charles Dickens has produced some exceptional characters to represent the complexity of each social class. From the arrogance of aristocracy to the struggle of the common workers, and the way in which they cope with the many hardships they will endure. Charles Dickens was able to personify the different social classes. The real reason why Charles Dickens wrote Hard Times was because he was low on funds, this was due to his sales being low on his periodical magazine “Household words”. He hoped by writing this novel in instalments would bale him out by increasing his profits. However, Dickends wished to satirize radical utilitarians who dickens thought to be ‘those who see figures and averages, and nothing else’. He also wished to campaign for reform of working conditions. In as early as 1839, dickens visted factories in Manchester and was appalled by the conditions workers had to work in. Furthermore, Charles Dickens gives us a close up look into what appears to be the ivory tower of the bourgeoisie of his day, yet these middle-class characters are viewed from a singular perspective, the perspective of those at the bottom of the social and economic system. Though Dickens characters tend to be well developed......

Words: 1120 - Pages: 5

Premium Essay

Hard Times

...Wednesday 24th march 2010 Essay Of ‘Hard times’ By Charles dickens In the novel Hard Times Dickens writes about a utilitarian education system. Dickens dislikes this form of education through his use of language and his characters. The title ’Hard Times’ shows us that dickens view of the utilitarian education system. “The one thing needful” and “Murdering the innocent” His dislike for this system is also shown through the novels characters names. ‘Mr Gradgrind’ and ‘Mr M’Choakumchild’. These names portray the system as it is choking the child and gradually grinding the children from their imagination. The chapter names ‘the one thing needful’’ we learn that that all Gradgrind cares about are facts so dickens title suggests that all facts are the only thing needed. While the title ‘murdering the innocent’ tells us that dickens feels the education system is killing the children minds and their childhoods and in turn being replaced by facts. I think dickens invented these names because emphasize his dislike for the utilitarian education system. The name 'Mr. Gradgrind' make the reader think of two words, gradually and grinding. It makes the reader think that 'Mr. Gradgrind' gradually grinds the childhoods out of the children. Further more the name 'Mr. M’Choakumchild' makes the reader automatically thinks the name is for choking the child. Dickens is again emphasizing his dislike for the education system, saying it is choking the child. The name also portrays him as a......

Words: 332 - Pages: 2

Premium Essay

Hard Times

...Hard Times: the Education System How does Dickens present the education system in hard Times? Words: | Submitted: Thu Mar 24 2005 ... Not even a sense of fancy and imagination. They were educated to get the basics of life because they were going to be pushed into the outside world at a very young age of 12 and above or even below. At the end of the day, the education was worthless because most of the children died in the workhouse. Dickens used Hard Times to criticise the society for failing so many of its children. Dickens argues against a mode of factory style, grad-grinding production that exterminates the fun out of life. He believes that education should not be a thing of going through volumes of head-breaking questions and being put through an immense variety of paces. Hard Times not only suggests that fancy is as important as fact, but it continually calls into question the difference between fact and fancy. Dickens suggests that what constitutes so-called fact is a matter... How does Dickens present his views on education in ‘hard times’? Words: | Submitted: Mon Jun 06 2005. He is shown as lifeless and colorless, 'the boy was so light-eyed and light-haired that the self-same rays appeared to draw out of him what little color he ever possessed.' This gives the effect that he has been drained of life and everything else but facts. When asked, Blitzer describes a Horse as a 'Quadruped' and 'graminivorous' and gives endless facts about the......

Words: 354 - Pages: 2

Premium Essay

Limitations of Historical Costing in Times of Inflation

...Buy this file: http://www.download-it.org/learning-resources.php?promoCode=&partnerID=&content=story&storyID=19988 CHAPTER 5 Normative theories of accounting 1: The case of accounting for changing prices Learning Objectives http://www.download-it.org/learning-resources.php?promoCode=&partnerID=&content=story&storyID=19988 Upon completing this chapter readers should: ◆ be aware of some particular limitations of historical cost accounting in terms of its ability to cope with various issues associated with changing prices; ◆ be aware of a number of alternative methods of accounting that have been developed to address problems associated with changing prices; ◆ be able to identify some of the strengths and weaknesses of the various alternative accounting methods; ◆ understand that the calculation of income under a particular method of accounting will depend on the perspective of capital maintenance that has been adopted. Opening issues Various asset valuation approaches are often adopted in the financial statements of large corporations. Fixed assets acquired (or perhaps revalued) in different years will simply be added together to give a total euro value, even though the various costs or valuations might provide little reflection of the current values of the respective assets. Issues to consider: (a) What are some of the criticisms that can be made in relation to the practice of accounting, wherein we add together, without adjustment, assets that have been......

Words: 1269 - Pages: 6

Free Essay

Hard Times

... Dickens supported the idea of quick thoughtful life, are free of the pursuit of material things. Gradgrind on the other hand, is insisting the only thing children need in their education is 'nothing but facts'. Dickens is worried about aggressive adults who rule children with fear and destroy their inquisitiveness 'the little vessels then and there arranged in order to have imperial gallons of facts poured into them'. The unimaginativeness of Gradgrind is emphasized by use of the word 'square' which is used five times and is echoed by the emphasis on straight lines and dark recess. Dickens describes the unimaginativeness of Gradgrind and his boring teaching methods. Gradgrinds repeated use of 'the emphasis was helped'. This shows how the school and Gradgrind are interlinked as these things are emphasized and that it is repetitive and boring. Dickens description of the schoolroom as a 'bare monotonous vault of a schoolroom' is an example of how Dickens uses place to back up his theories on education and utilitarianism. Like the schoolroom, that facts being taught are bland, boring and monotonous. The use of the word 'vault' suggests that the children's minds are being kept locked and are not open to possibilities of the world. Gradgrind's house, 'Stone Lodge' is described as a 'matter of fact home'. It is a very practical place just like its owner. For example the windows are compared to its 'Masters heavy brows'. Gradgrind's children have many educational aids and......

Words: 486 - Pages: 2

Free Essay

Hard Times

...How does Charles Dickens show his dislike for the education system? In the novel, 'Hard Times' , Dickens uses characterisation to show his dislike for the education system, for example, When he compares young girl number 'twenty' Sissy Jupe and Bitzer, the pale boy whose mind has been filled with 'Facts' which is emphasized by how many times Mr Grandgrind repeats it, is seen as more healthy than the boy Bitzer '..But, whereas the girl was so dark-eyed and dark-haired, that she seemed to receive a deeper and more lustrous colour from the sun, when it shone upon her, the boy was so light-eyed and light-haired that the self-same rays appeared to draw out of him what little colour he ever possessed.' This characteristic is but one way in which he shows that the young girl is imaginative and healthy, as she has not yet had facts poured into her mind, like the young boy Blitzer. When Blitzer is asked to define a horse, you would imagine a normal child to describe a horse as say, big and brown. However, because of Mr Gradgrinds, rationalist teachings, he simply states fact 'Quadruped. Graminivorous. Forty teeth, namely twenty-four grinders, four eye-teeth, and twelve incisive. Sheds coat in the spring; in marshy countries, sheds hoofs, too. Hoofs hard, but requiring to be shod with iron. Age known by marks in mouth.' Thurthermore, when Dickens' describes gradgrine he makes him out to be dull, lifeless and overall boring. His dislike is emphasized through......

Words: 434 - Pages: 2

Premium Essay

Hard Times Essay

...How does dickens show his dislike for the education system in 'Hard Times'? In the novel Hard Times Dickens writes about a utilitarian education system. Dickens dislikes this form of education through his use of language and his characters. The title shows us that dickens view of the utilitarian education system. “The one thing needful” and “Murdering the innocent” His dislike for this system is also shown through the novels characters names. ‘Mr Gradgrind’ and ‘Mr M’Choakumchild’. These names portray the system as it is choking the child and gradually grinding the children from their imagination. The chapter names ‘the one thing needful’’ we learn that that all Gradgrind cares about are facts so dickens title suggests that all facts are the only thing needed. While the title ‘murdering the innocent’ tells us that dickens feels the education system is killing the children minds and their childhoods and in turn being replaced by facts. I think dickens invented these names because emphasize his dislike for the utilitarian education system. The name 'Mr. Gradgrind' make the reader think of two words, gradually and grinding. It makes the reader think that 'Mr. Gradgrind' gradually grinds the childhoods out of the children. Further more the name 'Mr. M’Choakumchild' makes the reader automatically interpret the name for choking the child. Dickens is again emphasizing his dislike for the education system, saying it is choking the child. The name also portrays him as a man...

Words: 718 - Pages: 3

Premium Essay

Movie Review - Hard Times

...The most impressive aspect of the film Hard Times is its ability to accurately paint the divide between the upper and middle class during the industrial revolution without explicitly doing so. According to depictions in the film, working and living in an industrialized city was less than desirable. It was a time of poor work conditions, unfair wages, and unequal rights for women. It never explicitly addresses the poor work conditions in the film, but it’s evident they exist when the “hands” turn to the smooth talking union spokesman Slackbridge to attempt to unionize. The low wages is evident for both men and women at two different parts during the film. In the first part of the film, Louisa is forced to marry Josiah Bounderby because as her father puts it, “he has a substantially higher income then she’ll ever be able to earn.” Also, a worker in the factory named Stephen falls in love with a girl named Rachael, but is unable to obtain a divorce from his estranged wife because only the wealthy can afford them. It’s also evident from the film that life in early-industrialized cities was a time of unequal rights for woman. The women were subject to their man’s authority and wishes throughout the film. An example of this is where Bounderby, upset when he finds out that Louisa doesn’t love him, goes on a huge rant to Louisa’s father about how he can’t let her go because it would ruin his reputation and Louisa doesn’t appreciate him or all he’s done for her. Based on my......

Words: 536 - Pages: 3

Premium Essay

Surviving Plant World’s Hard Times

...In ten years, Plant World had grown from a one-person venture into the largest nursery and landscaping business in its area. Its founder, Myta Ong, combined a lifelong interest in plants with a botany degree to provide a unique customer service. Ong had managed the company’s growth so that even with twenty full-time employees working in six to eight crews, the organization culture was still as open, friendly, and personal as it had been when her only "employees" were friends who would volunteer to help her move a heavy tree. To maintain that atmosphere, Ong involved herself increasingly with people and less with plants as the company grew. With hundreds of customers and scores of jobs at any one time, she could no longer say without hesitation whether she had a dozen arborvitae bushes in stock or when Mrs. Carnack’s estate would need a new load of bark mulch. But she knew when Rose had been up all night with her baby, when Gary was likely to be late because he had driven to see his sick father over the weekend, and how to deal with Ellen when she was depressed because of her boyfriend’s behavior. She kept track of the birthdays of every employee and even those of their children. She was up every morning by five-thirty arranging schedules so that John could get his son out of daycare at four o’clock and Martina could be back in town for her afternoon high school equivalency classes. Paying all this attention to employees may have led Ong to make a single bad business......

Words: 627 - Pages: 3

Premium Essay

Hard Times in Ba

...Full Text. Web. 10 Apr. 2016. Item –pricing laws require a price tag on every item sold by a retailer, they studies this pricing and their efficiency by quantifying their costs and comparing them to others department store of drugstore, supermarket and others retail stores. My interest in this study isn’t about which department better price has for consumers but it’s about what we say and what we do. “As Michigan's Attorney General, I want you to know that every time you open your wallet, my office will be there to protect your transactions. Our state law requires that most items on store shelves be clearly marked with a price tag. If those price tags don't match the price scanned at the register, the law gives you specific rights. Keep this card in your wallet or purse and refer to it whenever you have a question about your item pricing rights. (Mike Cox, attorney general, August 28, 2002)”. This is a practical norm all over the country but it’s very different from what we actually do for example, My first time I went to a went to a store in America, it was to buy a bag of apples to which I was given $5 and to my surprise it was only $1.99 but they charge me $4.50. I letter learn that the $1.99 was not the price, but it was just the published prizes. Every state has its own rule on taxes, if those taxes apply to everyone, why not simply publish the price including taxes? Another reason for looking at this study is because even though stores have sales tax, they still......

Words: 1353 - Pages: 6

Free Essay

Hard Times

... mechanically operated version of a regular loom, an invention that combined threads to make cloth], which had been patented in 1785, rapidly became more widespread. This had a deleterious [injurious to health] effect on the hand loom weavers, who could not compete with the power loom and could no longer find sufficient work. By the time Dickens wrote Hard Times, power looms were the norm and hand weaving was almost extinct. Because of this development, weavers were gradually driven from their home-based weaving to the factories in the towns, which grew rapidly in population. The new factory workers put in ten-hour days. Conditions were often dangerous, and industrial accidents were common. This subject gave rise to a heated article written by Henry Morley and published in Dickens's own magazine, Household Words, in April 1854. Morley claimed that over the previous three years, there had been a hundred deaths and nearly twelve thousand accidents in factories in England. These figures were disputed by other contemporary commentators, but there is no doubt that many serious accidents did occur, often caused by unguarded machinery. In Hard Times, there is a reference to people being "chopped up" by machinery (Book 2, chapter 1). Factory workers sought to protect their own interests by joining trade unions, which were growing in power in the 1850s. But the unions often faced fierce opposition from employers. A notorious example of industrial conflict took place in Preston, a......

Words: 843 - Pages: 4

Premium Essay

Hard Times as a Moral Fable

...TOPIC:-What is Moral Fable? How can you say that Hard Times is a Moral Fable? BY: CHETAN ANKUR Moral fable combines the left (logical) & right (creative) side of the brain, so it both entertains creatively and validates certain types of behaviour, morally. The creative part is the fairy tale which often involves animals rather than humans. It speaks to our hearts as it entertains us; the ending is the logical, moral conclusion that satisfies our logical brains and seems "right". The problem with all moral fables is that there are often 2 sides to the same story ... things are rarely so black and white in reality ... so there could be more than one ending ... e.g. there are times when speed is necessary over steadiness - of course, there also has to be good judgement. Although it is not appropriate to describe a work of art, which Hard Times undoubtedly is, as a moral fable or a morality play, yet the fact remains that there is a strong moral intention behind this novel. Hard Times is a satirical attack on some of the evils and vices of Victorian society. Satire has always corrective purpose and is therefore basically moral in its approach to the subjects it deals with. Apart from that, there are passages of direct moralising in this novel. Hard Times is a novel which from the moment of its publication aroused very different sentiments in the reading public. Dickens's reasons for writing Hard Times were mostly monetary. Sales......

Words: 1949 - Pages: 8