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American Journal of Botany Jan 2013The relationship between fundamental plant biology and space biology was especially synergistic in the era of the Space Shuttle. While all terrestrial organisms are... (Review)
Review
The relationship between fundamental plant biology and space biology was especially synergistic in the era of the Space Shuttle. While all terrestrial organisms are influenced by gravity, the impact of gravity as a tropic stimulus in plants has been a topic of formal study for more than a century. And while plants were parts of early space biology payloads, it was not until the advent of the Space Shuttle that the science of plant space biology enjoyed expansion that truly enabled controlled, fundamental experiments that removed gravity from the equation. The Space Shuttle presented a science platform that provided regular science flights with dedicated plant growth hardware and crew trained in inflight plant manipulations. Part of the impetus for plant biology experiments in space was the realization that plants could be important parts of bioregenerative life support on long missions, recycling water, air, and nutrients for the human crew. However, a large part of the impetus was that the Space Shuttle enabled fundamental plant science essentially in a microgravity environment. Experiments during the Space Shuttle era produced key science insights on biological adaptation to spaceflight and especially plant growth and tropisms. In this review, we present an overview of plant science in the Space Shuttle era with an emphasis on experiments dealing with fundamental plant growth in microgravity. This review discusses general conclusions from the study of plant spaceflight biology enabled by the Space Shuttle by providing historical context and reviews of select experiments that exemplify plant space biology science.
Topics: Biology; Plants; Space Flight
PubMed: 23281389
DOI: 10.3732/ajb.1200338 -
Phytochemistry Apr 2015Reactive oxygen species (ROS) have been studied for their role in plant development as well as in plant immunity. ROS were consistently observed to accumulate in the... (Review)
Review
Reactive oxygen species (ROS) have been studied for their role in plant development as well as in plant immunity. ROS were consistently observed to accumulate in the plant after the perception of pathogens and microbes and over the years, ROS were postulated to be an integral part of the defence response of the plant. In this article we will focus on recent findings about ROS involved in the interaction of plants with pathogenic fungi. We will describe the ways to detect ROS, their modes of action and their importance in relation to resistance to fungal pathogens. In addition we include some results from works focussing on the fungal interactor and from studies investigating roots during pathogen attack.
Topics: Fungi; Host-Pathogen Interactions; Plant Leaves; Plant Roots; Plants; Reactive Oxygen Species
PubMed: 25264341
DOI: 10.1016/j.phytochem.2014.08.027 -
Pest Management Science Nov 2009Although Darwin knew of plant diseases, he did not study them as part of his analysis of natural selection. Effective plant disease control has only been developed after... (Review)
Review
Although Darwin knew of plant diseases, he did not study them as part of his analysis of natural selection. Effective plant disease control has only been developed after his death. This article explores the relevance of Darwin's ideas to three problem areas with respect to diseases caused by fungi: emergence of new diseases, loss of disease resistance bred into plants and development of fungicide resistance. Darwin's concept of change through natural or artificial selection relied on selection of many small changes, but subsequent genetic research has shown that change can also occur through large steps. Appearance of new diseases can involve gene duplication, transfer or recombination, but all evidence points to both host plant resistance and fungicide susceptibility being overcome through point mutations. Because the population size of diseases such as rusts and powdery and downy mildews is so large, all possible point mutations are likely to occur daily, even during moderate epidemics. Overcoming control measures therefore reflects the overall fitness of these mutants, and much resource effort is being directed towards assessment of their fitness, both in the presence and in the absence of selection. While recent developments in comparative genomics have caused some revision of Darwin's ideas, experience in managing plant disease control measures clearly demonstrates the relevance of concepts he introduced 150 years ago. It also reveals the remarkable speed and the practical impact of adaptation in wild microorganism populations to changes in their environment, and the difficulty of stopping or delaying such adaptation.
Topics: Biological Evolution; Breeding; Drug Resistance, Fungal; Fungi; Fungicides, Industrial; History, 19th Century; History, 20th Century; History, 21st Century; Immunity, Innate; Plant Diseases; Plants
PubMed: 19771541
DOI: 10.1002/ps.1845 -
Philosophical Transactions of the Royal... Sep 2016Land plants underpin a multitude of ecosystem functions, support human livelihoods and represent a critically important component of terrestrial biodiversity-yet many... (Review)
Review
Land plants underpin a multitude of ecosystem functions, support human livelihoods and represent a critically important component of terrestrial biodiversity-yet many tens of thousands of species await discovery, and plant identification remains a substantial challenge, especially where material is juvenile, fragmented or processed. In this opinion article, we tackle two main topics. Firstly, we provide a short summary of the strengths and limitations of plant DNA barcoding for addressing these issues. Secondly, we discuss options for enhancing current plant barcodes, focusing on increasing discriminatory power via either gene capture of nuclear markers or genome skimming. The former has the advantage of establishing a defined set of target loci maximizing efficiency of sequencing effort, data storage and analysis. The challenge is developing a probe set for large numbers of nuclear markers that works over sufficient phylogenetic breadth. Genome skimming has the advantage of using existing protocols and being backward compatible with existing barcodes; and the depth of sequence coverage can be increased as sequencing costs fall. Its non-targeted nature does, however, present a major informatics challenge for upscaling to large sample sets.This article is part of the themed issue 'From DNA barcodes to biomes'.
Topics: Biodiversity; DNA Barcoding, Taxonomic; Genome, Plant; Plants
PubMed: 27481790
DOI: 10.1098/rstb.2015.0338 -
Chimia Nov 2022Nematodes represent the most abundant group of metazoans on earth. They utilize diverse chemicals to interact with con-specific and hetero-specific organisms, and are... (Review)
Review
Nematodes represent the most abundant group of metazoans on earth. They utilize diverse chemicals to interact with con-specific and hetero-specific organisms, and are also impacted by compounds produced by other interacting organisms. In the first part of this review we discuss how nematode-derived glycolipids modulate their behavior and development, as well as the interactions with other organisms. Furthermore, we provide a short overview about other secondary metabolites produced by nematodes that affect different life traits of free-living nematodes. In the second part of this review we discuss how different bacteria-, nematode-, and plant-derived chemicals such as volatile organic compounds, root exudates, and plant defenses regulate the interaction between entomopathogenic nematodes, their symbiotic bacteria, insect prey, predators, and plants.
Topics: Animals; Nematoda; Ecology; Plants; Volatile Organic Compounds; Bacteria
PubMed: 38069790
DOI: 10.2533/chimia.2022.945 -
Pest Management Science May 2018Glyphosate has been shown to affect the development of plant disease in several ways. Plants utilize phenolic and other shikimic acid pathway-derived compounds as part... (Review)
Review
Glyphosate has been shown to affect the development of plant disease in several ways. Plants utilize phenolic and other shikimic acid pathway-derived compounds as part of their defense against pathogens, and glyphosate inhibits the biosynthesis of these compounds via its mode of action. Several studies have shown a correlation between enhanced disease and suppression of phenolic compound production after glyphosate. Glyphosate-resistant crop plants have also been studied for changes in resistance as a result of carrying the glyphosate resistance trait. The evidence indicates that neither the resistance trait nor application of glyphosate to glyphosate-resistant plants increases susceptibility to disease. The only exceptions to this are cases where glyphosate has been shown to reduce rust diseases on glyphosate-resistant crops, supporting a fungicidal role for this chemical. Finally, glyphosate treatment of weeds or volunteer crops can cause a temporary increase in soil-borne pathogens that may result in disease development if crops are planted too soon after glyphosate application. © 2017 Society of Chemical Industry.
Topics: Crops, Agricultural; Disease Susceptibility; Glycine; Herbicides; Plant Diseases; Glyphosate
PubMed: 28067016
DOI: 10.1002/ps.4521 -
Genetics May 2011The United States and the world face serious societal challenges in the areas of food, environment, energy, and health. Historically, advances in plant genetics have... (Review)
Review
The United States and the world face serious societal challenges in the areas of food, environment, energy, and health. Historically, advances in plant genetics have provided new knowledge and technologies needed to address these challenges. Plant genetics remains a key component of global food security, peace, and prosperity for the foreseeable future. Millions of lives depend upon the extent to which crop genetic improvement can keep pace with the growing global population, changing climate, and shrinking environmental resources. While there is still much to be learned about the biology of plant-environment interactions, the fundamental technologies of plant genetic improvement, including crop genetic engineering, are in place, and are expected to play crucial roles in meeting the chronic demands of global food security. However, genetically improved seed is only part of the solution. Such seed must be integrated into ecologically based farming systems and evaluated in light of their environmental, economic, and social impacts-the three pillars of sustainable agriculture. In this review, I describe some lessons learned, over the last decade, of how genetically engineered crops have been integrated into agricultural practices around the world and discuss their current and future contribution to sustainable agricultural systems.
Topics: Agriculture; Conservation of Natural Resources; Food Supply; Internationality; Plants; Plants, Genetically Modified
PubMed: 21546547
DOI: 10.1534/genetics.111.128553 -
Journal of Experimental Botany Oct 2014Some beneficial plant-interacting bacteria can biologically fix N2 to plant-available ammonium. Biological nitrogen fixation (BNF) is an important source of nitrogen (N)... (Review)
Review
Some beneficial plant-interacting bacteria can biologically fix N2 to plant-available ammonium. Biological nitrogen fixation (BNF) is an important source of nitrogen (N) input in agriculture and represents a promising substitute for chemical N fertilizers. Diazotrophic bacteria have the ability to develop different types of root associations with different plant species. Among the highest rates of BNF are those measured in legumes nodulated by endosymbionts, an already very well documented model of plant-diazotrophic bacterial association. However, it has also been shown that economically important crops, especially monocots, can obtain a substantial part of their N needs from BNF by interacting with associative and endophytic diazotrophic bacteria, that either live near the root surface or endophytically colonize intercellular spaces and vascular tissues of host plants. One of the best reported outcomes of this association is the promotion of plant growth by direct and indirect mechanisms. Besides fixing N, these bacteria can also produce plant growth hormones, and some species are reported to improve nutrient uptake and increase plant tolerance against biotic and abiotic stresses. Thus, this particular type of plant-bacteria association consists of a natural beneficial system to be explored; however, the regulatory mechanisms involved are still not clear. Plant N status might act as a key signal, regulating and integrating various metabolic processes that occur during association with diazotrophic bacteria. This review will focus on the recent progress in understanding plant association with associative and endophytic diazotrophic bacteria, particularly on the knowledge of the N networks involved in BNF and in the promotion of plant growth.
Topics: Bacteria; Crops, Agricultural; Endophytes; Models, Biological; Nitrogen; Nitrogen Fixation; Plant Root Nodulation; Plant Roots; Plants; Signal Transduction; Symbiosis
PubMed: 25114015
DOI: 10.1093/jxb/eru319 -
Annals of Botany Aug 2017The growing wealth of knowledge on whole-plant genome sequences is highlighting the key role of transposable elements (TEs) in plant evolution, as a driver of drastic... (Review)
Review
BACKGROUND
The growing wealth of knowledge on whole-plant genome sequences is highlighting the key role of transposable elements (TEs) in plant evolution, as a driver of drastic changes in genome size and as a source of an important number of new coding and regulatory sequences. Together with polyploidization events, TEs should thus be considered the major players in evolution of plants.
SCOPE
This review outlines the major mechanisms by which TEs impact plant genome evolution and how polyploidy events can affect these impacts, and vice versa. These include direct effects on genes, by providing them with new coding or regulatory sequences, an effect on the epigenetic status of the chromatin close to genes, and more subtle effects by imposing diverse evolutionary constraints to different chromosomal regions. These effects are particularly relevant after polyploidization events. Polyploidization often induces bursts of transposition probably due to a relaxation in their epigenetic control, and, in the short term, this can increase the rate of gene mutations and changes in gene regulation due to the insertion of TEs next to or into genes. Over longer times, TE bursts may induce global changes in genome structure due to inter-element recombination including losses of large genome regions and chromosomal rearrangements that reduce the genome size and the chromosome number as part of a process called diploidization.
CONCLUSIONS
TEs play an essential role in genome and gene evolution, in particular after polyploidization events. Polyploidization can induce TE activity that may explain part of the new phenotypes observed. TEs may also play a role in the diploidization that follows polyploidization events. However, the extent to which TEs contribute to diploidization and fractionation bias remains unclear. Investigating the multiple factors controlling TE dynamics and the nature of ancient and recent polyploid genomes may shed light on these processes.
Topics: DNA Transposable Elements; Evolution, Molecular; Genome Size; Genome, Plant; Plants; Polyploidy
PubMed: 28854566
DOI: 10.1093/aob/mcx078 -
Annual Review of Plant Biology Apr 2017Priming is an adaptive strategy that improves the defensive capacity of plants. This phenomenon is marked by an enhanced activation of induced defense mechanisms.... (Review)
Review
Priming is an adaptive strategy that improves the defensive capacity of plants. This phenomenon is marked by an enhanced activation of induced defense mechanisms. Stimuli from pathogens, beneficial microbes, or arthropods, as well as chemicals and abiotic cues, can trigger the establishment of priming by acting as warning signals. Upon stimulus perception, changes may occur in the plant at the physiological, transcriptional, metabolic, and epigenetic levels. This phase is called the priming phase. Upon subsequent challenge, the plant effectively mounts a faster and/or stronger defense response that defines the postchallenge primed state and results in increased resistance and/or stress tolerance. Priming can be durable and maintained throughout the plant's life cycle and can even be transmitted to subsequent generations, therefore representing a type of plant immunological memory.
Topics: Epigenesis, Genetic; Host-Pathogen Interactions; Plant Physiological Phenomena; Plants; Signal Transduction; Stress, Physiological
PubMed: 28226238
DOI: 10.1146/annurev-arplant-042916-041132