Relevant bibliographies by topics / Plants – Evolution

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Plants – Evolution'

Author: Grafiati
Published: 4 June 2021
Last updated: 31 July 2024

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Journal articles on the topic "Plants – Evolution"

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Preston, Jill. "The Evolution of Plants." BioScience 67, no. 6 (June 2017): 577–78. http://dx.doi.org/10.1093/biosci/bix030.

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Raven, John A. "The evolution of plants." Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology 153, no. 2 (June 2009): S44. http://dx.doi.org/10.1016/j.cbpa.2009.04.489.

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Lebeda, A. "Robert J. Henry (editor): Plant Diversity and Evolution: Genotypic and Phenotypic Variation in Higher Plants – Book Review." Plant Protection Science 41, No. 3 (March 7, 2010): 123–24. http://dx.doi.org/10.17221/2730-pps.

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Schiavinato, Matteo, Alexandrina Bodrug‐Schepers, Juliane C. Dohm, and Heinz Himmelbauer. "Subgenome evolution in allotetraploid plants." Plant Journal 106, no. 3 (March 24, 2021): 672–88. http://dx.doi.org/10.1111/tpj.15190.

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Schlessman, Mark A. "Investigating Evolution with Living Plants." American Biology Teacher 59, no. 8 (October 1, 1997): 472–79. http://dx.doi.org/10.2307/4450361.

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WEI, Qiang, Yong-Hong LIANG, and Guang-Lin LI. "Evolution of miRNA in plants." Hereditas (Beijing) 35, no. 3 (September 27, 2013): 315–23. http://dx.doi.org/10.3724/sp.j.1005.2013.00315.

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Pearson, Lorentz C. "Evolution & Diversity in Plants." American Biology Teacher 50, no. 8 (November 1, 1988): 487–95. http://dx.doi.org/10.2307/4448808.

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Stuessy, Tod F., Gerhard Jakubowsky, Roberto Salguero Gomez, Martin Pfosser, Philipp M. Schluter, Tomas Fer, Byung-Yun Sun, and Hidetoshi Kato. "Anagenetic evolution in island plants." Journal of Biogeography 33, no. 7 (July 2006): 1259–65. http://dx.doi.org/10.1111/j.1365-2699.2006.01504.x.

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Thorpe, Andrea S., Erik T. Aschehoug, Daniel Z. Atwater, and Ragan M. Callaway. "Interactions among plants and evolution." Journal of Ecology 99, no. 3 (February 23, 2011): 729–40. http://dx.doi.org/10.1111/j.1365-2745.2011.01802.x.

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Donoghue, Philip, and Jordi Paps. "Plant Evolution: Assembling Land Plants." Current Biology 30, no. 2 (January 2020): R81—R83. http://dx.doi.org/10.1016/j.cub.2019.11.084.

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Dissertations / Theses on the topic "Plants – Evolution"

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Puzey, Joshua Robert. "Plant MicroRNA Evolution and Mechanisms of Shape Change in Plants." Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10143.

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Plant microRNAs have been shown to have important roles in regulating diverse processes ranging from reproductive development to stress response. In the first two chapters, I focus on miRNA diversity in Aquilegia studying both anciently evolved broadly conserved and rapidly evolving species specific miRNAs. In chapter one, I utilize Aquilegia's critical phylogenetic position between the well developed models Arabidopsis thaliana and Oryza sativa to study the evolution of ancient miRNAs across the angiosperms. In chapter two, I utilize smallRNA high-throughput sequencing to annotate Aquilegia specific miRNAs and, in the process, uncover the novel regulation of a floral homeotic gene by an Aquilegia-specific miRNA. In chapter three, I look at the tissue specific development of miRNA regulation in the bioenergetically relevant model organism Populus trichocarpa. High-throughput smallRNA sequencing from four diverse tissue sets including leaves, xylem, mechanically treated xylem, and pooled vegetative and reproductive tissues were analyzed, revealing a total of 155 previously unannotated miRNAs, most of which are P. trichocarpa specific. Expanding on my work with the petal identity pathway, I turned a broader analysis of Aquilegia petal spurs. Petal spurs are the distinguishing characteristic of Aquilegia and are argued to be a key innovation in the adaptive radiation of the genus. In the fourth chapter, I explore the cellular basis of extreme spur length diversity in the genus and find that a single parameter, cell shape, can explain this morphological range. Next, I seek to describe the cellular patterns that give rise to a spur primoridia from an initially flat laminar petal and find that spur initiation is characterized by concentrated, prolonged, and oriented cell divisions. Inspired by this quantitative analysis of growth, chapter five looks at the mechanisms of shape change in cucumber tendrils. I find that anisotropic contraction of a multi-layered gelatinous fiber ribbon explains coiling in cucumbers. Surprisingly, we discover that tendrils display twistless-overwinding when pulled and exhibit an unforeseen force-extension response as a result. These results provide the design basis for twistless springs with tunable mechanical responses and serve as a clear example of how the biological systems can inspire applied mechanical designs.
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Wied, Anna. "Conspecific nurse effects and the evolution of monocarpy in plants /." free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9841363.

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Haig, David. "Applications of allocation and kinship models to the interpretation of vascular plant life cycles." Phd thesis, Australia : Macquarie University, 1990. http://hdl.handle.net/1959.14/23227.

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Thesis by publication.
Thesis (PhD) -- Macquarie University, School of Biological Sciences, 1990.
Bibliography: leaves 269-324.
Introduction -- Models of parental allocation -- Sex expression in homosporous pteridophytes -- The origin of heterospory -- Pollination and the origin of the seed habit -- Brood reduction in gymnosperms -- Pollination: costs and consequences -- Adaptive explanations for the rise of the angiosperms -- Parent-specific gene expression and the triploid endosperm -- New perspectives on the angiosperm female gametophyte -- Overview -- Glossary -- Kinship terms in plants -- Literature Cited.
Among vascular plants/ different life cycles are associated with characteristic ranges of propagule size. In the modern flora, isospores of homosporous pteridophytes are almost all smaller than 150 urn diameter, megaspores of heterosporous pteridophytes fall in the range 100-1000 urn diameter, gymnosperm seeds are possibly all larger than the largest megaspores, but the smallest angiosperm seeds are of comparable size to large isospores. -- Propagule size is one of the most important features of a sporophyte's reproductive strategy. Roughly speaking, larger propagules have larger food reserves, and a greater probability of successful establishment, than smaller propagules, but a sporophyte can produce more smaller propagules from the same quantity of resources. Different species have adopted very different size-versus-number compromises. The characteristic ranges of propagule size, in each of the major groups of vascular plants, suggest that some life cycles are incompatible with particular size-versus-number compromises. -- Sex expression in homosporous plants is a property of gametophytes (homosporous sporophytes are essentially asexual). Gametophytes should produce either eggs or sperm depending on which course of action gives the greatest chance of reproductive success. A maternal gametophyte must contribute much greater resources to a young sporophyte than the paternal gametophyte. Therefore, smaller gametophytes should tend to reproduce as males, and gametophytes with abundant resources should tend to reproduce as females. Consistent with these predictions, large female gametophytes release substances (antheridiogens) which induce smaller neighbouring ametophytes to produce sperm. -- The mechanism of sex determination in heterosporous species appears to be fundamentally different. Large megaspores develop into female gametophytes, and small icrospores develop into male gametophytes. Sex expression appears to be determined by the sporophyte generation. This is misleading. As argued above, the optimal sex expression of a homosporous gametophyte is influenced by its access to resources. This is determined by (1) the quantity of food reserves in its spore and (2) the quantity of resources accumulated by the gametophyte's own activities. If a sporophyte produced spores of two sizes, gametophytes developing from the larger spores' would be more likely to reproduce as females than gametophytes developing from the smaller spores, because the pre-existing mechanisms of sex determination would favor production of archegonia by larger gametophytes. Thus, the predicted mechanisms of sex determination in homosporous species could also explain the differences in sex expression of gametophytes developing from large and small spores in heterosporous species.
Megaspores of living heterosporous pteridophytes contain sufficient resources for female reproduction without photosynthesis by the gametophyte (Platyzoma excepted), whereas microspores only contain sufficient resources for male reproduction. Furthermore, many more microspores are produced than megaspores. A gametophyte's optimal sex expression is overwhelmingly determined by the amount of resources supplied in its spore by the sporophyte, and is little influenced by the particular environmental conditions where the spore lands. Gametophytes determine sex expression in heterosporous species, as well as homosporous species. A satisfactory model for the evolution of heterospory needs to explain under what circumstances sporophytes will benefit from producing spores of two distinct sizes. -- In Chapter 4, I present a model for the origin of heterospory that predicts the existence of a "heterospory threshold". For propagule sizes below the threshold, homosporous reproduction is evolutionarily stable because gametophytes must rely on their own activities to accumulate sufficient resources for successful female reproduction. Whether a gametophyte can accumulate sufficient resources before its competitors is strongly influenced by environmental conditions. Gametophytes benefit from being able to adjust their sex expression in response to these conditions. For propagule sizes above the threshold, homosporous reproduction is evolutionarily unstable, because the propagule's food reserves are more than sufficient for a "male" gametophyte to fertilize all eggs within its neighbourhood. A population of homosporous sporophytes can be invaded by sporophytes that produce a greater number of smaller spores which could land in additional locations and fertilize additional eggs. Such'spores would be male-specialists on account of their size. Therefore, both spore types would be maintained in the population because of frequency-dependent selection. -- The earliest vascular plants were homosporous. Several homosporous groups gave rise to heterosporous lineages, at least one of which was the progeniture of the seed plants. The first heterosporous species appear in the Devonian. During the Devonian, there was a gradual increase in maximum spore size, possibly associated with the evolution of trees and the appearance of the first forests. As the heterospory threshold was approached, the optimal spore size for female reproduction diverged from the optimal spore size for male reproduction. Below the threshold, a compromise spore size gave the highest fitness returns to sporophytes, but above the threshold, sporophytes could attain higher fitness by producing two types of spores. -- The evolution of heterospory had profound consequences. Once a sporophyte produced two types of spores, microspores and megaspores could become specialized for male and female function respectively. The most successful heterosporous lineage (or lineages) is that of the seed plants. The feature that distinguishes seed plants from other heterosporous lineages is pollination, the capture of microspores before, rather than after, propagule dispersal. Traditionally, pollination has been considered to be a major adaptive advance because it frees sexual reproduction from dependence on external fertilization by freeswimming sperm, but pollination has a more important advantage. In heterosporous pteridophytes, a megaspore is provisioned whether or not it will be fertilized whereas seeds are only provisioned if they are pollinated.
The total cost per seed cannot be assessed solely from the seed's energy and nutrient content. Rather, each seed also has an associated supplementary cost of adaptations for pollen capture and of resources committed to ovules that remain unpollinated. The supplementary cost per seed has important consequences for understanding reproductive strategies. First, supplementary costs are expected to be proportionally greater for smaller seeds. Thus, the benefits of decreasing seed size (in order to produce more seeds) are reduced for species with small seeds. This effect may explain minimum seed sizes. Second, supplementary costs are greater for populations at lower density. Thus, there is a minimum density below which a species cannot maintain its numbers. -- By far the most successful group of seed plants in the modern flora are the angiosperms. Two types of evidence suggest that early angiosperms had a lower supplementary cost per seed than contemporary gymnosperms. First, the minimum size of angiosperm seeds was much smaller than the minimum size of gymnosperm seeds. This suggests that angiosperms could produce small seeds more cheaply than could gymnosperms. Second, angiosperm-dominated floras were more speciose than the gymnosperm-dominated floras they replaced. This suggests that the supplementary cost per seed of angiosperms does not increase as rapidly as that of gymnosperms, as population density decreases. In consequence, angiosperms were able to displace gymnosperms from many habitats, because the angiosperms had a lower cost of rarity. -- Angiosperm embryology has a number of distinctive features that may be related to the group's success. In gymnosperms, the nutrient storage tissue of the seed is the female gametophyte. In most angiosperms, this role is taken by the endosperm. Endosperm is initiated by the fertilization of two female gametophyte nuclei by a second sperm that is genetically identical to the sperm which fertilizes the egg. Endosperm has identical genes to its associated embryo, except that there are two copies of maternal genes for every copy of a paternal gene. -- Chapter 9 presents a hypothesis to explain the unusual genetic constitution of endosperm. Paternal genes benefit from their endosperm receiving more resources than the amount which maximizes the fitness of maternal genes, and this conflict is expressed as parent-specific gene expression in endosperm. The effect of the second maternal genome is to increase maternal control of nutrient acquisition. -- Female gametophytes of angiosperms are traditionally classified as monosporic, bisporic or tetrasporic. Bisporic and tetrasporic embryo sacs contain the derivatives of more than one megaspore nucleus. Therefore, there is potential for conflict between the different nuclear types within an embryo sac, but this possibility has not been recognized by plant embryologists. In Chapter 10, I show that many previously inexplicable observations can be understood in terms of genetic conflicts within the embryo sac.
Mode of access: World Wide Web.
324 leaves ill
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Maher, Keri Renee. "A geographically constrained molecular phylogeny of Panamanian Aechmea species (Bromeliaceae, subfamily bromelioideae)." CSUSB ScholarWorks, 2007. https://scholarworks.lib.csusb.edu/etd-project/3280.

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This study lends strong support to the idea that members of Bromeliaceae have undergone a recent adaptive radiation, and therefore show that, at least in part, diversity in the tropics is due to a fast speciation rate and that the tropics can be a "cradle" for new diversification and exploitation of varying ecological niches through the diversification of ecophysiological traits within a lineage.
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Campbell, Lesley Geills. "Rapid evolution in a crop-weed complex (Raphanus spp.)." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1166549627.

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Lindh, Magnus. "Evolution of Plants : a mathematical perspective." Doctoral thesis, Umeå universitet, Institutionen för matematik och matematisk statistik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-119458.

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The Earth harbors around 300 000 plant species. The rich and complex environment provided by plants is considered a key factor for the extraordinary diversity of the terrestrial fauna by, for example, providing food and shelter. This thesis contributes to the understanding of these questions by investigating how the interplay of physiology, demography, and evolution gives rise to variation and diversity in fundamental plant traits. This will help us answer questions such as: How has this amazing diversity of plant species emerged? Which mechanisms maintain diversity? How are plant strategies and plant diversity influenced by variations in the environment? A plant faces multiple problems to survive and reproduce successfully. These problems can be modeled by considering traits, trade-offs and a fitness measure. For example: How to maximize growth rate, while maximizing structural stability? I will investigate four plant models in order to understand the function of plants, and mechanisms promoting diversity.  Paper I: We study how annual plants with and without growth constraints should optimize their flowering time when productivity or season length changes. With a dynamic ontogenetic growth model and optimal control theory we prove that a bang-bang reproductive control is optimal under constrained growth and constant mortality rate. We find that growth constraints can flip the direction of optimal phenological response for increasing productivity. The reason is that the growth rate of vegetative mass saturates at high productivity and therefore it is better to flower earlier and take advantage of a longer reproductive period. If season length extends equally both in the beginning and the end of the season, growth constraints control the direction of the optimal response as well. Our theory can help explaining phenological patterns along productivity gradients, and can be linked to empirical observations made on a calendar scale. Paper II: We introduce a new measure of tree crown-rise efficiency based on the loss of biomass of the tree during growth. The more mass the tree looses during growth, the less crown-rise efficient it is. Top-heavy shapes loose more biomass than bottom-heavy shapes. Light-use efficiency is defined as the mean light assimilation of the leaves in the crown times the ratio of leaf mass and total mass. We then study the trade-off between light-use efficiency to crown-rise efficiency for tree crown shapes. We assume that the total tree mass is constant, and a constant vertical light gradient represent the shading from a surrounding forest. We find large differences in crown shapes at intermediate vertical light gradient, when both self-shading and mean-field shading are important, suggesting light-use vs crown-rise efficiency as a new trade-off that can explain tree diversity. Our crown-rise efficiency measure could easily be integrated into existing forest models. Paper III: We extend an evolutionary tree crown model, where trees with different heights compete for light, with drought-induced mortality rates depending on ground-water availability and the depth of an optional taproot. The model does not include competition for ground water. Our model explains how ground-water availability can shape plant communities, when taproot and non-taproot strategies can coexist, and when only one of these strategies can persist. We investigate how emerging plant diversity varies with water table depth, soil water gradient and drought-induced mortality rate. The taproot enables plants to reach deep water, thus reducing mortality, but also carries a construction cost, thus inducing a trade-off. We find that taproots maintain plant diversity under increasing drought mortality, and that taproots evolve when groundwater is accessible at low depths. There are no viable strategies at high drought mortality and deep water table. Red Queen evolutionary dynamics appear at intermediate drought mortality in mixed communities with and without taproots, as the community never reaches a final evolutionarily stable composition. Paper IV: We extend a size-structured plant model, with self-shading and two evolving traits, crown top-heaviness and crown width-to-height ratio. The model allows us to identify salient trade-offs for the crown shape. The most important trade-off for top-heaviness is light-use efficiency vs crownrise efficiency, and the most important trade-off for width-to-height ratio is self-shading vs branch costs. We find that when the two traits coevolve; the outcome is a single common evolutionarily stable strategy (ESS), far away from the highest net primary production (NPP). When only sun angle is decreasing with increasing latitude both the crown width-to-height ratio and crown top-heaviness decrease. However, when light response in addition to the sun angle decreases with increasing latitude, the crown width-to-height ratio is nearly invariant of latitude except at low site productivity when the ratio decreases with latitude. Top-heaviness is always decreasing with increasing latitude. Finally, we find that crown top-heaviness increases with the NPP or leaf-area index (LAI) at ESS, but crown width-to-height ratio is maximal at an intermediate NPP or LAI.
Artikel I: Arters reproduktionsframgång (fitness), till exempel antal avkommor eller frön som produceras under livet, är ofta avgörande för huruvida de är evolutionärt framgångsrika eller inte. Här undersöker vi hur ettåriga växter med eller utan tillväxtbegränsningar ska optimera sin blomningstid när produktivitet eller säsongslängd ändras. Det är optimalt att gå direkt från tillväxt till blomning när tillväxten är begränsad och dödligheten är konstant. Vid ökad produktivitet sker blomningen tidigare med tillväxtbegränsningar men senare utan tillväxtbegränsningar, vilket beror på att med tillväxtbegränsningar ökar den vegetativa massan långsamt. Därför är det bättre att blomma tidigare och ta tillvara på en längre reproduktionsperiod. Vi får samma resultat om säsongslängden ökar lika mycket i början och slutet av säsongen. Vår teori kan bidra till att förutsäga blomningstider vid produktivitetsförändringar och säsongsförändringar. Artikel II: Tillväxten hos träd kan begränsas av brist på ljus, vatten, och näring, men också genom förlust av grenar. Vi introducerar ett nytt mått på tillväxteffektiviteten hos trädkronor baserat på förlust av biomassa under trädets tillväxt. Ju mer massa trädet förlorar under tillväxt, desto mindre tillväxteffektiva är de. Topptunga former förlorar mer biomassa än bottentunga former. Vi studerar avvägningar mellan ljuseffektivitet och tillväxteffektivitet för trädformer, där ljuseffektiviteten definieras som medelljusupptaget för löven i kronan. Vi antar en konstant totalmassa, och en statisk vertikal skuggning som representerar skuggningen från en omgivande skog. Vi hittar stora skillnader i kronformer vid en medelhög skuggning, då både självskuggningen och medelskuggningen har betydelse. Vårt mått för tillväxteffektivitet kan enkelt integreras i existerande skogsmodeller. Studien visar att avvägningar mellan tillväxteffektivitet och ljuseffektivitetet kan vara viktig för mångfalden av trädformer i en skog. En överraskande upptäckt är att konformade eller sfäriska trädkronor aldrig är effektiva, men däremot timglasformade kronor. Artikel III: Växter kan försvara sig på olika sätt mot torka, till exempel genom att rulla ihop bladen eller genom att reproducera tidigare och därigenom undvika uttdragen torka. Här undersöker vi fördelarna med en pålrot vid torka. En pålrot är en rot som växer nedåt för att nå djupliggande grundvatten. Vi utvidgar en evolutionär modell av trädkronor med grundvatten och en pålrot, där träd med olika höjd konkurrerar om ljus. Det finns ingen konkurrens om vatten. Vi undersöker hur mångfalden hos träden beror på vattendjup, vattengradient och dödlighet orsakad av torka. Med hjälp av pålroten kan träden nå djupt vatten och därigenom minska dödligheten, men den medför också en kostnad, så en avvägning måste göras. Vi ser att pålrötter upprätthåller mångfalden hos växterna vid ökad mortalitet, och att pålrötter uppstår när grundvattnet är grunt. Det finns inga strategier som kan överleva om grundvattnet är djupt och dödligheten är hög. Vår modell kan förklara hur grundvatten kan förändra sammansättningen på trädsamhällen, när träd med och utan pålrot kan samexistera, och under vilka förutsättningar endast en av strategierna förväntas dominera. Artikel IV: Träd som växer upp i en skog måste konkurrera med andra träd om ljus, framförallt större träd. Detta ger upphov till en asymmetrisk ljuskonkurrens, där de små träden hämmas av större träd. Små träd har därmed små chanser att överleva utom då skogen nyligen störts och det öppnas upp en glänta. Vid denna ljuskonkurrens kan man anta att trädkronans form har stor betydelse för trädets framgång. Frågan är hur de evolutionärt fördelaktiga kronformerna beror på latituden och produktiviteten. Vi antar att latituden påverkar solens genomsnittliga vinkel och ljusrespons. Vi utvidgar en storleksstrukturerad trädmodell med självskuggning där två evolverande egenskaper beskriver kronans topptyngd och bredd. Med modellen kan vi undersöka vilka strategiska avvägningar som bestämmer om kronans form blir konkurrenskraftig. En topptung krona har högt ljusupptag eftersom det finns mest ljus högt upp i grenverket. Å andra sidan har den en låg tillväxteffektivitet eftersom topptunga kronor måste tappa mycket grenar för att behålla sin form. En bred krona har en låg självskuggning eftersom bladen är utspridda. Å andra sidan har den höga kostnader för de långa grenar som krävs. Vi finner att när dessa egenskaper evolverar tillsammans så finns endast en evolutionärt stabil strategi (ESS), långt från den högsta nettoproduktionen. När endast solvinkeln minskar med ökande latitud minskar både kronans bredd och topptyngd, men när både solvinkel och ljusrespons minskar med ökande latitud så är bredden nästan oförändrad utom vid låg produktivitet då den minskar med latituden. Kronans topptyngd minskar alltid med latituden. Slutligen ser vi hur kronans topptyngd alltid ökar med nettoproduktionen vid ESS, medan kronans bredd har ett maxium för ett mellanvärde hos nettoproduktionen vid ESS.
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Sun, Zhiying. "Pattern formation and evolution on plants." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/194905.

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Phyllotaxis, namely the arrangement of phylla (leaves, florets, etc.) has intrigued natural scientists for over four hundred years. Statistics show that about 90\% of the spiral patterns has their numbers of spirals belonging to two consecutive members of the regular Fibonacci sequence. (Fibonacci(-like) sequences refer to any sequences constructed with the addition rule $a_{j+2}=a_{j}+a_{j+1}$, while the regular Fibonacci sequence refers to the particular sequences 1,1,2,3,5,8,13,...) Historical research on pattern formation on plants, tracing back to as early as four hundred years ago, was mostly geometry based. Current studies focus on the activities on the cellular level and study initiation of primordia (the initial undifferentiated form of phylla) as a morphogenesis process cued by some signal. The nature of the signal and the mechanisms governing the distribution of the signal are still under investigation. The two top candidates are the biochemical hormone auxin distribution and the mechanical stresses in the plant surface (tunica). We built a model which takes into consideration the interactions between these mechanisms. In addition, this dissertation explores both analytically and numerically the conditions for the Fibonacci-like patterns to continuously evolve (i.e. as the mean radius of the generative annulus changes over time, the numbers of spirals in the pattern increase or decreases along the same Fibonacci-like sequence), as well as for different types of pattern transitions to occur. The essential condition for the Fibonacci patterns to continuously evolve is that the patterns are formed annulus by annulus on a circular domain and the pattern-forming mechanism is dominated by a quadratic nonlinearity. The predominance of the regular Fibonacci pattern is determined by the pattern transitions at early stages of meristem growth. Furthermore, Fibonacci patterns have self-similar structures across different radii, and there exists a one-to-one mapping between any two Fibonacci-like patterns. The possibility of unifying the previous theory of optimal packing on phyllotaxis and the solutions of current mechanistic partial differential equations is discussed.
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Kilaru, Aruna. "The Early Evolution of Land Plants." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etsu-works/4762.

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Wang, Sishuo. "Evolution of duplicated non-coding RNAs in plants." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/63301.

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Harris, Mark Steven. "The evolution of sexual dimorphism in flowering plants." Thesis, University of Oxford, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442466.

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Books on the topic "Plants – Evolution"

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J, Doyle Jeff, and Gaut Brandon S, eds. Plant molecular evolution. Dordrecht: Kluwer, 2000.

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Garassino, Alessandro. Plants: Origins and evolution. Austin, Tex: Raintree Steck-Vaughn, 1995.

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C, McElwain J., ed. The evolution of plants. New York: Oxford University Press, 2002.

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Bill, Eddie, ed. Plants: Evolution and diversity. Cambridge, UK: Cambridge University Press, 2006.

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J, Smartt, and Simmonds N. W. 1922-, eds. Evolution of crop plants. 2nd ed. Harlow, Essex, England: Longman Scientific and Technical, 1995.

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Ambrose, Barbara A., and Michael D. Purugganan. The evolution of plant form. Hoboken [N.J.]: Wiley-Blackwell, 2012.

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Allessio, Leck Mary, Parker V. Thomas, and Simpson Robert, eds. Seedling ecology and evolution. Cambridge: Cambridge University Press, 2008.

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Ingrouille, Martin. Diversity and evolution of land plants. London: Chapman & Hall, 1992.

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Klekowski, Edward J. Mutation, developmental selection, and plant evolution. New York: Columbia University Press, 1988.

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D, Briggs. Plant variation and evolution. 3rd ed. New York: Cambridge University Press, 1997.

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Book chapters on the topic "Plants – Evolution"

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Budyko, M. I. "Plants." In The Evolution of the Biosphere, 99–137. Dordrecht: Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-009-4556-2_4.

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Bard, Jonathan. "The Evolution of Algae and Plants." In Evolution, 125–40. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9780429346217-14.

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Kubitzki, K., P. J. Rudall, and M. C. Chase. "Systematics and Evolution." In Flowering Plants · Monocotyledons, 23–33. Berlin, Heidelberg: Springer Berlin Heidelberg, 1998. http://dx.doi.org/10.1007/978-3-662-03533-7_3.

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Lack, Andrew, and David Evans. "Evolution of flowering plants." In Plant Biology, 317–24. 2nd ed. London: Taylor & Francis, 2021. http://dx.doi.org/10.1201/9780203002902-93.

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Pedersen, Bård. "Senescence in Plants." In Life History Evolution in Plants, 239–74. Dordrecht: Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-010-9460-3_8.

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Walter, David Evans, and Heather C. Proctor. "Mites on Plants." In Mites: Ecology, Evolution & Behaviour, 281–339. Dordrecht: Springer Netherlands, 2013. http://dx.doi.org/10.1007/978-94-007-7164-2_8.

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Zielinski, Marie-Luise, and Ortrun Mittelsten Scheid. "Meiosis in Polyploid Plants." In Polyploidy and Genome Evolution, 33–55. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-31442-1_3.

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Ingrouille, Martin. "Cultivated plants: conclusion." In Diversity and Evolution of Land Plants, 291–96. Dordrecht: Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-011-2300-6_9.

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Pearson, Lorentz C. "The Flowering Plants." In The Diversity and Evolution of Plants, 523–74. Boca Raton: CRC Press, 2023. http://dx.doi.org/10.1201/9781003419877-22.

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Evert, Ray F., and Susan E. Eichhorn. "The Process of Evolution." In Raven Biology of Plants, 209–31. New York: Macmillan Learning, 2013. http://dx.doi.org/10.1007/978-1-319-15626-8_12.

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Conference papers on the topic "Plants – Evolution"

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Demchenko, K. N. "Root systems evolution: from lateral root initiation strategy to branch plasticity." In IX Congress of society physiologists of plants of Russia "Plant physiology is the basis for creating plants of the future". Kazan University Press, 2019. http://dx.doi.org/10.26907/978-5-00130-204-9-2019-16.

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Evkaykina, A. I., E. A. Klimova, E. V. Tyutereva, K. S. Dobryakova, A. N. Ivanova, C. Rydin, L. Berke, et al. "Evolution of the mechanisms of regulation of the apical meristem and laying of leaves in vascular plants." In IX Congress of society physiologists of plants of Russia "Plant physiology is the basis for creating plants of the future". Kazan University Press, 2019. http://dx.doi.org/10.26907/978-5-00130-204-9-2019-160.

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"Evolution of MLO-like proteins in flowering plants." In Plant Genetics, Genomics, Bioinformatics, and Biotechnology. Novosibirsk ICG SB RAS 2021, 2021. http://dx.doi.org/10.18699/plantgen2021-162.

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Zhang, Fan, Qing Li, and Ying Luo. "Evolution of Skill Training in Nuclear Power Plants." In 2021 IEEE International Conference on Engineering, Technology & Education (TALE). IEEE, 2021. http://dx.doi.org/10.1109/tale52509.2021.9678641.

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Cheng, Zhonghua, Zhe Dong, and Bowen Li. "Control Strategies Evolution of Nuclear Plant: From Obninsk to HTR-PM." In 2022 29th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/icone29-91296.

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Abstract Since the first commercial nuclear plant Obninsk began to operate, there have been dozens of types of nuclear plants studied, designed, or constructed nowadays driven by the key issue: how to enhance the economic competitiveness of nuclear plants while ensuring safety. Research on the key issue stimulated the evolution of nuclear plants, which simultaneously brought an array of various control problems for each generation and ultimately attributed to the evolution of control strategies of nuclear plants. In this paper, the main development route of nuclear plants is presented with a concise introduction to the representative design of nuclear plants for each generation. Meanwhile, the corresponding control problems brought by the design and/or the safety requirement document, national and international requirements, and so forth, were analyzed with emphasis on the Gen IV multi-modular high-temperature gas-cooled reactor (MHTGR). On account of the requirement to cooperate with other renewable energies to achieve the “Emission peak, Carbon neutrality” through the improvement of operation flexibility of NPP, most SMR plants work in the reactor following mode which requires more R&D efforts on the coordination control and load-following control to enhance economic advantages of SMR plants, etc.
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"Regulation and evolution of flavonoid biosynthesis pathway in polyploid plants." In Plant Genetics, Genomics, Bioinformatics, and Biotechnology. Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 2019. http://dx.doi.org/10.18699/plantgen2019-187.

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"Analysis of the evolution of gene expression patterns in flowering plants." In Plant Genetics, Genomics, Bioinformatics, and Biotechnology. Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 2019. http://dx.doi.org/10.18699/plantgen2019-137.

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Oh, Hyun-Woo. "Phytochemical co-evolution between insects and plants through plant diterpenes and insect juvenile hormone receptors." In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.110912.

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Likholat, Yu V., A. N. Vinnichenko, O. O. Drobakhin, I. A. Oginova, N. M. Subotina, V. N. Pokataev, L. L. Shirokopoyas, V. V. Hobotov, and Yu A. Elanskiy. "The mm-wave application for optimization of plants’ evolution." In Telecommunication Technology" (CriMiCo 2008). IEEE, 2008. http://dx.doi.org/10.1109/crmico.2008.4676632.

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Kumar, Pravesh, and Millie Pant. "Noisy source recognition in multi noise plants by differential evolution." In 2013 IEEE Symposium on Swarm Intelligence (SIS). IEEE, 2013. http://dx.doi.org/10.1109/sis.2013.6615189.

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Reports on the topic "Plants – Evolution"

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Berner, Robert A. Plants, Weathering, and the Evolution of Atmospheric Carbon Dioxide and Oxygen. Office of Scientific and Technical Information (OSTI), February 2008. http://dx.doi.org/10.2172/923048.

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Ullman, Diane, James Moyer, Benjamin Raccah, Abed Gera, Meir Klein, and Jacob Cohen. Tospoviruses Infecting Bulb Crops: Evolution, Diversity, Vector Specificity and Control. United States Department of Agriculture, September 2002. http://dx.doi.org/10.32747/2002.7695847.bard.

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Objectives. The overall goal of the proposed research was to develop a mechanistic understanding of tospovirus evolution, diversity and vector specificity that could be applied to development of novel methods for limiting virus establishment and spread. Our specific objectives were: 1) To characterize newly intercepted tospoviruses in onion, Hippeastrum and other bulb crops and compare them with the known tomato spotted wilt virus (TSWV) and its isolates; 2) To characterize intra- and interspecific variation in the virus transmission by thrips of the new and distinct tospoviruses. and, 3) To determine the basis of vector specificity using biological, cellular and molecular approaches. Background. New tospoviruses infecting bulb crops were detected in Israel and the US in the mid-90s. Their plant host ranges and relationships with thrips vectors showed they differed from the type member of the Tospovirus genus, tomato spotted wilt virus (TSWV). Outbreaks of these new viruses caused serious crop losses in both countries, and in agricultural and ornamental crops elsewhere. In the realm of plant infecting viruses, the tospoviruses (genus: Tospovirus , family: Bunyaviridae ) are among the most aggressive emerging viruses. Tospoviruses are transmitted by several species of thrips in a persistent, propagative fashion and the relationships between the viruses and their thrips vectors are often specific. With the emergence of new tospoviruses, new thrips vector/tospovirus relationships have also arisen and vector specificities have changed. There is known specificity between thrips vector species and particular tospoviruses, although the cellular and molecular bases for this specificity have been elusive. Major conclusions, solutions and achievements. We demonstrated that a new tospovirus, iris yellow spot virus (IYSV) caused "straw bleaching" in onion (Allium cepa) and lisianthus necrosis in lisianthus (Eustoma russellianum). Characterization of virus isolates revealed genetic diversity among US, Brazilian, Dutch and Israeli isolates. IYSV was not seed transmitted, and in Israel, was not located in bulbs of infected plants. In the US, infected plants were generated from infected bulbs. The relationship between IYSV and Thrips tabaci was shown to be specific. Frankliniella occidentalis, the primary vector of many other tospoviruses, did not transmit IYSV isolates in Israel or the US. Furthermore, 1': tabaci populations varied in their transmission ability. Transmission was correlated to IYSV presence in thrips salivary glands. In Israel, surveys in onion fields revealed that the onion thrips, Thrips tabaci Lindeman was the predominant species and that its incidence was strongly related to that of IYSV infection. In contrast, in the U.S., T. tabaci and F. occidentalis were present in high numbers during the times sampled. In Israel, insecticides reduced onion thrips population and caused a significant yield increase. In the US, a genetic marker system that differentiates non-thrips transmissible isolates from thrips transmissible isolate demonstrated the importance of the M RNA to thrips transmission of tospoviruses. In addition, a symbiotic Erwinia was discovered in thrips and was shown to cause significant artifacts in certain types of virus binding experiments. Implications, scientific and agricultural. Rapid emergence of distinct tospoviruses and new vector relationships is profoundly important to global agriculture. We advanced the understanding of IYSV in bulb crops and its relationships with thrips vector species. The knowledge gained provided growers with new strategies for control and new tools for studying the importance of particular viral proteins in thrips specificity and transmission efficiency.
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Ohad, Nir, and Robert Fischer. Control of Fertilization-Independent Development by the FIE1 Gene. United States Department of Agriculture, August 2000. http://dx.doi.org/10.32747/2000.7575290.bard.

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A fundamental problem in biology is to understand how fertilization initiates reproductive development. During plant reproduction, one sperm cell fuses with the egg to form an embryo, whereas a second sperm cell fuses with the adjacent central cell nucleus to form the endosperm tissue that supports embryo and/or seedling development. To understand the mechanisms that initiate reproduction, we have isolated mutants of Arabidopsis that allow for replication of the central cell and subsequent endosperm development without fertilization. In this project we have cloned the MEA gene and showed that it encode a SET- domain polycomb protein. Such proteins are known to form chromatin-protein complexes that repress homeotic gene transcription and influence cell proliferation from Drosophylla to mammals. We propose a model whereby MEA and an additional polycomb protein we have cloned, FIE , function to suppress a critical aspect of early plant reproduction and endosperm development, until fertilization occurs. Using a molecular approach we were able to determine that FIE and MEA interact physically, suggesting that these proteins have been conserved also during the evolution of flowering plants. The analysis of MEA expression pattern revealed that it is an imprinted gene that displays parent-of- origin-dependent monoallelic expression specifically in the endosperm tissue. Silencing of the paternal MEA allele in the endosperm and the phenotype of mutant mea seeds support the parental conflict theory for the evolution of imprinting in plants and mammals. These results contribute new information on the initiation of endosperm development and provide a unique entry point to study asexual reproduction and apomixis which is expected to improve crop production.
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Alarcón, Arturo, Juan Alberto, Cecilia Correa, Edwin Malagon, Emilio Sawada, Hector Baldivieso, and Gabriel Rocha. Analysis of the Policy and Market Framework for Hydro Pumped Storage in Latin America and the Caribbean. Inter-American Development Bank, October 2021. http://dx.doi.org/10.18235/0003721.

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In the next decades, the evolution of the power sector in the region will be based on a combination of large-scale and centralized power plants, distributed generation, and even isolated microgrids. Storage technologies will be crucial to enable the management of the intrinsic variability of some renewable generation (wind and solar), particularly in scenarios where there is a need to reduce fossil fuels used for base generation. Pumped Storage Hydropower (PSH) technologies are an attractive alternative, given the regions hydropower potential, existing installed capacity, and technical knowledge. This paper explores the policy and market framework in LAC for this technology.
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Pichersky, Eran, Alexander Vainstein, and Natalia Dudareva. Scent biosynthesis in petunia flowers under normal and adverse environmental conditions. United States Department of Agriculture, January 2014. http://dx.doi.org/10.32747/2014.7699859.bard.

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The ability of flowering plants to prosper throughout evolution, and for many crop plants to set fruit, is strongly dependent on their ability to attract pollinators. To that end many plants synthesize a spectrum of volatile compounds in their flowers. Scent is a highly dynamic trait that is strongly influenced by the environment. However, with high temperature conditions becoming more common, the molecular interplay between this type of stress and scent biosynthesis need to be investigated. Using petunia as a model system, our project had three objectives: (1) Determine the expression patterns of genes encoding biosynthetic scent genes (BSGs) and of several genes previously identified as encoding transcription factors involved in scent regulation under normal and elevated temperature conditions. (2) Examine the function of petunia transcription factors and a heterologous transcription factor, PAPl, in regulating genes of the phenylpropanoid/benzenoid scent pathway. (3) Study the mechanism of transcriptional regulation by several petunia transcription factors and PAPl of scent genes under normal and elevated temperature conditions by examining the interactions between these transcription factors and the promoters of target genes. Our work accomplished the first two goals but was unable to complete the third goal because of lack of time and resources. Our general finding was that when plants grew at higher temperatures (28C day/22C night, vs. 22C/16C), their scent emission decreased in general, with the exception of a few volatiles such as vanillin. To understand why, we looked at gene transcription levels, and saw that generally there was a good correlation between levels of transcriptions of gene specifying enzymes for specific scent compounds and levels of emission of the corresponding scent compounds. Enzyme activity levels, however, showed little difference between plants growing at different temperature regimes. Plants expressing the heterologous gene PAPl showed general increase in scent emission in control temperature conditions but emission decreased at the higher temperature conditions, as seen for control plants. Finally, expression of several transcription factor genes decreased at high temperature, but expression of new transcription factor, EOB-V, increased, implicating it in the decrease of transcription of BSGs. The major conclusion of this work is that high temperature conditions negatively affect scent emission from plants, but that some genetic engineering approaches could ameliorate this problem.
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Schuster, Gadi, and David Stern. Integration of phosphorus and chloroplast mRNA metabolism through regulated ribonucleases. United States Department of Agriculture, August 2008. http://dx.doi.org/10.32747/2008.7695859.bard.

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New potential for engineering chloroplasts to express novel traits has stimulated research into relevant techniques and genetic processes, including plastid transformation and gene regulation. This proposal continued our long time BARD-funded collaboration research into mechanisms that influence chloroplast RNA accumulation, and thus gene expression. Previous work on cpRNA catabolism has elucidated a pathway initiated by endonucleolytic cleavage, followed by polyadenylation and exonucleolytic degradation. A major player in this process is the nucleus-encoded exoribonuclease/polymerasepolynucleotidephoshorylase (PNPase). Biochemical characterization of PNPase has revealed a modular structure that controls its RNA synthesis and degradation activities, which in turn are responsive to the phosphate (P) concentration. However, the in vivo roles and regulation of these opposing activities are poorly understood. The objectives of this project were to define how PNPase is controlled by P and nucleotides, using in vitro assays; To make use of both null and site-directed mutations in the PNPgene to study why PNPase appears to be required for photosynthesis; and to analyze plants defective in P sensing for effects on chloroplast gene expression, to address one aspect of how adaptation is integrated throughout the organism. Our new data show that P deprivation reduces cpRNA decay rates in vivo in a PNPasedependent manner, suggesting that PNPase is part of an organismal P limitation response chain that includes the chloroplast. As an essential component of macromolecules, P availability often limits plant growth, and particularly impacts photosynthesis. Although plants have evolved sophisticated scavenging mechanisms these have yet to be exploited, hence P is the most important fertilizer input for crop plants. cpRNA metabolism was found to be regulated by P concentrations through a global sensing pathway in which PNPase is a central player. In addition several additional discoveries were revealed during the course of this research program. The human mitochondria PNPase was explored and a possible role in maintaining mitochondria homeostasis was outlined. As polyadenylation was found to be a common mechanism that is present in almost all organisms, the few examples of organisms that metabolize RNA with no polyadenylation were analyzed and described. Our experiment shaded new insights into how nutrient stress signals affect yield by influencing photosynthesis and other chloroplast processes, suggesting strategies for improving agriculturally-important plants or plants with novel introduced traits. Our studies illuminated the poorly understood linkage of chloroplast gene expression to environmental influences other than light quality and quantity. Finely, our finding significantly advanced the knowledge about polyadenylation of RNA, the evolution of this process and its function in different organisms including bacteria, archaea, chloroplasts, mitochondria and the eukaryotic cell. These new insights into chloroplast gene regulation will ultimately support plant improvement for agriculture
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Ullman, Diane E., Benjamin Raccah, John Sherwood, Meir Klein, Yehezkiel Antignus, and Abed Gera. Tomato Spotted Wilt Tosporvirus and its Thrips Vectors: Epidemiology, Insect/Virus Interactions and Control. United States Department of Agriculture, November 1999. http://dx.doi.org/10.32747/1999.7573062.bard.

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Objectives. The major aim of the proposed research was to study thrips-TSWV relationships and their role in the epidemiology of the virus with the aim of using this knowledge to reduce crop losses occurring due to epidemics. Our specific objectives were: To determine the major factors involved in virus outbreaks, including: a) identifying the thrips species involved in virus dissemination and their relative role in virus spread; b) determining the virus sources among wild and cultivated plants throughout the season and their role in virus spread, and, c) determining how temperature and molecular variations in isolates impact virus replication in plants and insects and impact the transmission cycle. Background to the topic. Tospoviruses are among the most important emerging plant viruses that impact production of agricultural and ornamental crops. Evolution of tospoviruses and their relationships with thrips vector species have been of great interest because of crop damage caused world wide and the complete absence of suitable methods of control. Tospoviruses threaten crops in Israel and the United States. By understanding the factors contributing to epidemics and the specific relationships between thrips species and particular tospoviruses we hope that new strategies for control can be developed that will benefit agriculture in both Israel and the United States. Major conclusions, solutions, achievements. We determined that at least three tospoviruses were involved in epidemics in Israel and the United States, tomato spotted wilt virus (TSWV), impatiens necrotic spot virus (INSV) and iris yellow spot virus (IYSV). We detected and characterized INSV for the first time in Israel and, through our efforts, IYSV was detected and characterized for the first time in both countries. We demonstrated that many thrips species were present in commercial production areas and trap color influenced thrips catch. Frankliniella occidentalis was the major vector species of INSV and TSWV and populations varied in transmission efficiency. Thrips tabaci is the sole known vector of IYSV and experiments in both countries indicated that F. occidentalis is not a vector of this new tospovirus. Alternate plant hosts were identified for each virus. A new monitoring system combining sticky cards and petunia indicator plants was developed to identify sources of infective thrips. This system has been highly successful in the U.S. and was used to demonstrate to growers that removal of plant sources of infective thrips has a dramatic impact on virus incidence. Finally, a putative thrips receptor mediating acquisition of TSWV was discovered. Implications, scientific and agricultural. Our findings have contributed to new control measures that will benefit agriculture. Identification of a putative thrips receptor for TSWV and our findings relative to thrips/tospovirus specificity have implications for development of innovative new control strategies.
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Friedman, Haya, Julia Vrebalov, James Giovannoni, and Edna Pesis. Unravelling the Mode of Action of Ripening-Specific MADS-box Genes for Development of Tools to Improve Banana Fruit Shelf-life and Quality. United States Department of Agriculture, January 2010. http://dx.doi.org/10.32747/2010.7592116.bard.

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Fruit deterioration is a consequence of a genetically-determined fruit ripening and senescence programs, in which developmental factors lead to a climacteric rise of ethylene production in ethylene-sensitive fruits such as tomato and banana. Breeding of tomato with extended fruit shelf life involves the incorporation of a mutation in RIN, a MADS-box transcription factor participating in developmental control signalling of ripening. The RIN mode of action is not fully understood, and it may be predicted to interact with other MADS-box genes to execute its effects. The overall goal of this study was to demonstrate conservation of ripening control functions between banana and tomato and thus, the potential to genetically extend shelf-life in banana based on tools developed in tomato. The specific objectives were: 1. To increase the collection of potential RIN-like genes from banana; 2. To verify their action as developmental regulators; 3. To elucidate MADS-box gene mode of action in ripening control; 4. To create transgenic banana plants that express low levels of endogenous Le-RIN- like, MaMADS- gene(s). We have conducted experiments in banana as well as in tomato. In tomato we have carried out the transformation of the tomato rin mutant with the MaMADS1 and MaMADS2 banana genes. We have also developed a number of domain swap constructs to functionally examine the ripening-specific aspects of the RIN gene. Our results show the RIN-C terminal region is essential for the gene to function in the ripening signalling pathway. We have further explored the tomato genome databases and recovered an additional MADS-box gene necessary for fruit ripening. This gene has been previously termed TAGL1 but has not been functionally characterized in transgenic plants. TAGL1 is induced during ripening and we have shown via RNAi repression that it is necessary for both fleshy fruit expansion and subsequent ripening. In banana we have cloned the full length of six MaMADS box genes from banana and determined their spatial and temporal expression patterns. We have created antibodies to MaMADS2 and initiated ChI assay. We have created four types of transgenic banana plants designed to reduce the levels of two of the MaMADS box genes. Our results show that the MaMADS-box genes expression in banana is dynamically changing after harvest and most of them are induced at the onset of the climacteric peak. Most likely, different MaMADS box genes are active in the pulp and peel and they are differently affected by ethylene. Only the MaMADS2 box gene expression is not affected by ethylene indicating that this gene might act upstream to the ethylene response pathway. The complementation analysis in tomato revealed that neither MaMADS1 nor MaMADS2 complement the rin mutation suggesting that they have functionally diverged sufficiently to not be able to interact in the context of the tomato ripening regulatory machinery. The developmental signalling pathways controlling ripening in banana and tomato are not identical and/or have diverged through evolution. Nevertheless, at least the genes MaMADS1 and MaMADS2 constitute part of the developmental control of ripening in banana, since transgenic banana plants with reduced levels of these genes are delayed in ripening. The detailed effect on peel and pulp, of these transgenic plants is underway. So far, these transgenic bananas can respond to exogenous ethylene, and they seem to ripen normally. The response to ethylene suggest that in banana the developmental pathway of ripening is different than that in tomato, because rin tomatoes do not ripen in response to exogenous ethylene, although they harbor the ethylene response capability This study has a major contribution both in scientific and agricultural aspects. Scientifically, it establishes the role of MaMADS box genes in a different crop-the banana. The developmental ripening pathway in banana is similar, but yet different from that of the model plant tomato and one of the major differences is related to ethylene effect on this pathway in banana. In addition, we have shown that different components of the MaMADS-box genes are employed in peel and pulp. The transgenic banana plants created can help to further study the ripening control in banana. An important and practical outcome of this project is that we have created several banana transgenic plants with fruit of extended shelf life. These bananas clearly demonstrate the potential of MaMADS gene control for extending shelf-life, enhancing fruit quality, increasing yield in export systems and for improving food security in areas where Musaspecies are staple food crops.
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Cochran, J., D. Lew, and N. Kumar. Flexible Coal: Evolution from Baseload to Peaking Plant (Brochure). Office of Scientific and Technical Information (OSTI), December 2013. http://dx.doi.org/10.2172/1110465.

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Singh, Anjali. Estimating the Chiasma Frequency in Diplotene-Diakinesis Stage. ConductScience, September 2020. http://dx.doi.org/10.55157/cs20200925.

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Chiasma is the point of crossing over or site where the exchange of genetic material takes place between two homologous, non-sister chromatids. The crossover occurs in the pachytene stage, however, it is observed in the diplotene stage of meiosis-I[2]. The cross-over between the two homologs also creates a new combination of parental genes, forming recombinants. The recombination of the genes causes variation in the population and exert a profound effect on genomic diversity and evolution. Meiotic recombination and variation in the population have been a concern for scientists to understand the impact and significance of crossing over in a population. Over time, various techniques, such as immunolocalization and electron microscopy of recombination nodules[2], were discovered for the analysis of meiotic recombination and quantification of crossing over. However, estimation of chiasma frequency is the traditional method followed widely to understand the phenomenon. Chiasma Frequency is defined as the estimation of the level of genetic recombination in a population. It is especially very effective to estimate the genetic recombination in organisms in which genetic analysis is impossible/difficult to perform[2]. So, this article is a layout of the origin of the concept of chiasmata, the factors affecting chiasma frequency, and its distribution in chromosomes. Also discussed, is the procedure for estimating chiasma frequency in plants as well as animals.
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