175.2 million hectares of biotech crops were grown globally in 2013. In the United States, the first commercialized drought-tolerant maize (MON87460) expressing Bacillus subtilis cold shock protein B (cspB) was planted by 2,000 farmers over 50,000 hectares. Indonesia also approved drought-tolerant sugarcane expressing choline dehydrogenase (betA), which accumulates membrane-protectant glycine betaine. Other drought-resistant varieties of sugarcane, maize, wheat and rice are also in field trials in Argentina, Brazil, India, Egypt, South Africa, Kenya and Uganda. Brazil continues to lead the world in annual growth (10%) of transgenic acreage.
For almost a century the plant hormone auxin has been central to theories on apical dominance, whereby the growing shoot tip suppresses the growth of the axillary buds below. According to the classic model, the auxin indole-3-acetic acid is produced in the shoot tip and transported down the stem, where it inhibits bud growth. We report here that the initiation of bud growth after shoot tip loss cannot be dependent on apical auxin supply because we observe bud release up to 24 h before changes in auxin content in the adjacent stem. After the loss of the shoot tip, sugars are rapidly redistributed over large distances and accumulate in axillary buds within a timeframe that correlates with bud release. Moreover, artificially increasing sucrose levels in plants represses the expression of BRANCHED1 (BRC1), the key transcriptional regulator responsible for maintaining bud dormancy, and results in rapid bud release. An enhancement in sugar supply is both necessary and sufficient for suppressed buds to be released from apical dominance. Our data support a theory of apical dominance whereby the shoot tip’s strong demand for sugars inhibits axillary bud outgrowth by limiting the amount of sugar translocated to those buds.
Betalains are plant pigments with high antioxidant and cancer chemopreventive properties used by the food industry as safe colorants. Betalains are restricted to species of the order Caryophyllales and difficulty in obtaining individual molecules has limited their structural identification and application. This study was designed to develop a betalamic acid-derivatized support generated from a primary amine polymer. The novel material presents color properties of a pseudo-betaxanthin and it is stable for at least six months. The bond formed can be displaced at mild conditions by the addition of amines in aqueous solutions over a broad pH range and at 25 ºC. This releases the betalamic acid while forming the corresponding pigment. This one-step procedure significantly simplifies the process of obtaining semi-synthetic betalains and it is optimized here for the formation of betaxanthins and betacyanins derived from tyramine, dopamine, pyrrolidine and indoline. The new method makes access to single betalains available to the entire scientific community and could stimulate research and applications in the field.
Global food and biofuel production and their vulnerability in a changing climate are of paramount societal importance. However, current global model predictions of crop photosynthesis are highly uncertain. Here we demonstrate that new space-based observations of chlorophyll fluorescence, an emission intrinsically linked to plant biochemistry, enable an accurate, global, and time-resolved measurement of crop photosynthesis, which is not possible from any other remote vegetation measurement. Our results show that chlorophyll fluorescence data can be used as a unique benchmark to improve our global models, thus providing more reliable projections of agricultural productivity and climate impact on crop yields. The enormous increase of the observational capabilities for fluorescence in the very near future strengthens the relevance of this study.
Photosynthesis is the process by which plants harvest sunlight to produce sugars from carbon dioxide and water. It is the primary source of energy for all life on Earth; hence it is important to understand how this process responds to climate change and human impact. However, model-based estimates of gross primary production (GPP, output from photosynthesis) are highly uncertain, in particular over heavily managed agricultural areas. Recent advances in spectroscopy enable the space-based monitoring of sun-induced chlorophyll fluorescence (SIF) from terrestrial plants. Here we demonstrate that spaceborne SIF retrievals provide a direct measure of the GPP of cropland and grassland ecosystems. Such a strong link with crop photosynthesis is not evident for traditional remotely sensed vegetation indices, nor for more complex carbon cycle models. We use SIF observations to provide a global perspective on agricultural productivity. Our SIF-based crop GPP estimates are 50–75% higher than results from state-of-the-art carbon cycle models over, for example, the US Corn Belt and the Indo-Gangetic Plain, implying that current models severely underestimate the role of management. Our results indicate that SIF data can help us improve our global models for more accurate projections of agricultural productivity and climate impact on crop yields. Extension of our approach to other ecosystems, along with increased observational capabilities for SIF in the near future, holds the prospect of reducing uncertainties in the modeling of the current and future carbon cycle.
Disease incidences related to Escherichia coli and Salmonella enterica infections by consumption of (fresh) vegetables, sprouts, and occasionally fruits made clear that these pathogens are not only transmitted to humans via the "classical" routes of meat, eggs, and dairy products, but also can be transmitted to humans via plants or products derived from plants. Nowadays, it is of major concern that these human pathogens, especially the ones belonging to the taxonomical family of Enterobacteriaceae, become adapted to environmental habitats without losing their virulence to humans. Adaptation to the plant environment would lead to longer persistence in plants, increasing their chances on transmission to humans via consumption of plant-derived food. One of the mechanisms of adaptation to the plant environment in human pathogens, proposed in this paper, is horizontal transfer of genes from different microbial communities present in the arable ecosystem, like the ones originating from soil, animal digestive track systems (manure), water and plants themselves. Genes that would confer better adaptation to the phytosphere might be genes involved in plant colonization, stress resistance and nutrient acquisition and utilization. Because human pathogenic enterics often were prone to genetic exchanges via phages and conjugative plasmids, it was postulated that these genetic elements may be hold key responsible for horizontal gene transfers between human pathogens and indigenous microbes in agroproduction systems. In analogy to zoonosis, we coin the term phytonosis for a human pathogen that is transmitted via plants and not exclusively via animals.
Microtubules (MTs) play a crucial role in the anisotropic deposition of cell wall material, thereby affecting the direction of growth. A wide range of tip-growing cells display highly polarized cell growth, and MTs have been implicated in regulating directionality and expansion. However, the molecular machinery underlying MT dynamics in tip-growing plant cells remains unclear. Here, we show that highly dynamic MT bundles form cyclically in the polarized expansion zone of the moss Physcomitrella patens caulonemal cells through the coalescence of growing MT plus ends. Furthermore, the plant-specific kinesins (KINID1) that are is essential for the proper MT organization at cytokinesis also regulate the turnover of the tip MT bundles as well as the directionality and rate of cell growth. The plus ends of MTs grow toward the expansion zone, and KINID1 is necessary for the stability of a single coherent focus of MTs in the center of the zone, whose formation coincides with the accumulation of KINID1. We propose that KINID-dependent MT bundling is essential for the correct directionality of growth as well as for promoting growth per se. Our findings indicate that two localized cell wall deposition processes, tip growth and cytokinesis, previously believed to be functionally and evolutionarily distinct, share common and plant-specific MT regulatory components.
Metabolic engineering strategies for production of plant natural products.
Methods for genome targeting of mutations and gene insertions.
Recent advances for elucidation of plant secondary biosynthetic pathways.
Metabolic engineering of paclitaxel biosynthesis in vitro.
Production of β-carotene in Golden Rice and other food crops.
Historically, plants are a vital source of nutrients and pharmaceuticals. Recent advances in metabolic engineering have made it possible to not only increase the concentration of desired compounds, but also introduce novel biosynthetic pathways to a variety of species, allowing for enhanced nutritional or commercial value. To improve metabolic engineering capabilities, new transformation techniques have been developed to allow for gene specific silencing strategies or stacking of multiple genes within the same region of the chromosome. The ‘omics’ era has provided a new resource for elucidation of uncharacterized biosynthetic pathways, enabling novel metabolic engineering approaches. These resources are now allowing for advanced metabolic engineering of plant production systems, as well as the synthesis of increasingly complex products in engineered microbial hosts. The status of current metabolic engineering efforts is highlighted for the in vitro production of paclitaxel and the in vivoproduction of β-carotene in Golden Rice and other food crops.
The great German plant physiologist Wilhelm Pfeffer rightly claimed that “no plant is entirely without the power of movement” (1). If this fact remains underappreciated, it is perhaps because plant movements typically unfold over minutes, hours, or days, and thus exceed the attention span of all but the most dedicated observer. Among the large array of plant movements, the tropisms—that is, those movements that are directed toward or away from an external stimulus such as gravity or light—are the most fascinating because they highlight beautifully the sentient nature of plants and the goal-directedness of their growth habit. The pervasiveness of plant tropisms is revealed when one stops to consider the unlikeliness that seeds lodged haphazardly within the crevices of a rugged terrain should sprout stems that reliably find their way up. Were it not for the ability of the young plants to sense light and gravity, forests would be impenetrable tangles of stems and branches growing in all directions. Their prevalence in the plant kingdom explains why tropisms have been an active area of research since the beginning of the 19th century. By the end of the 19th century, the field had reached such a level of development and popularity that eminent biologists, including Charles Darwin and Pfeffer, could devote entire books to the topic (1, 2). Given this long and illustrious tradition of research, one might expect today’s biologists to have extracted all useful information from standard observational research of plant tropisms. A paper published in PNAS should convince the readers that much can still be learned from careful, quantitative observation of biological processes. In a systematic study of shoot gravitropism in 11 taxa, Bastien et al. (3) at once establish the universal response to gravity as a process of initial stem curving followed by apical straightening and debunk the idea that current models of gravitropism offer a plausible explanation for the process.
Wind has major effect on plants, from growth changes to windbreaks. Therefore, there is a crucial need for non-invasive methods to describe and quantify the complex motion of a plant induced by wind. In this paper two methods based on video sequences analysis are studied. An adaptation of the classical Particle Image Velocimetry method (nat-PIV) is compared with a tracking method based on the optical flow method of Lukas and Kanade, initialized with the features selection method of Shi and Tomasi (ST + KLT). Both methods were benchmarked on an experiment on a walnut tree in open-field conditions submitted to different wind flows at different periods of the year and equipped with 3D magnetic tracking. The metrological assessment was performed in two steps. We first tested if the results given by both methods were significantly different. Secondly, a direct assessment of the two methods versus 3D magnetic tracking was performed. The ST + KLT method proved to be more accurate and robust than nat-PIV one. The outputs of the ST + KLT method are independent of the foliage density, wind velocity and of light gradient intrinsic to outdoor scene. The implementation of ST + KLT method developed for this study in Matlab is freely available.
Pine tree yields longest genome ever sequenced CBS News Understanding the loblolly pine's genetic code could lead to improved breeding of the tree, which is used to make paper and lumber and is being investigated as a potential biofuel, the...
Even though pigmentation traits have had substantial impacts on the field of animal evolutionary developmental biology, they have played only relatively minor roles in plant evo-devo. This is surprising given the often direct connection between flower color and fitness variation mediated through the effects of pollinators. At the same time, ecological and evolutionary genetic studies have utilized the molecular resources available for the anthocyanin pathway to generate several examples of the molecular basis of putatively adaptive transitions in flower color. Despite this opportunity to synthesize experimental approaches in ecology, evolution, and developmental biology, the investigation of many fundamental questions in evo-devo using this powerful model is only at its earliest stages. For example, a long-standing question is whether predictable genetic changes accompany the repeated evolution of a trait. Due to the conserved nature of the biochemical and regulatory control of anthocyanin biosynthesis, it has become possible to determine whether, and under what circumstances, different types of mutations responsible for flower color variation are preferentially targeted by natural selection. In addition, because plants use anthocyanin and related compounds in vegetative tissue for other important physiological functions, the identification of naturally occurring transitions from unpigmented to pigmented flowers provides the opportunity to examine the mechanisms by which regulatory networks are co-opted into new developmental domains. Here, we review what is known about the ecological and molecular basis of anthocyanic flower color transitions in natural systems, focusing on the evolutionary and developmental features involved. In doing so, we provide suggestions for future work on this trait and suggest that there is still much to be learned from the evolutionary development of flower color transitions in nature.
Background and Aims Transgene introgression from crops into wild relatives may increase the resistance of wild plants to herbicides, insects, etc. The chance of transgene introgression depends not only on the rate of hybridization and the establishment of hybrids in local wild populations, but also on the metapopulation dynamics of the wild relative. The aim of the study was to estimate gene flow in a metapopulation for assessing and managing the risks of transgene introgression.
Methods Wild carrots (Daucus carota) were sampled from 12 patches in a metapopulation. Eleven microsatellites were used to genotype wild carrots. Genetic structure was estimated based on the FST statistic. Contemporary (over the last several generations) and historical (over many generations) gene flow was estimated with assignment and coalescent methods, respectively.
Key Results The genetic structure in the wild carrot metapopulation was moderate (FST = 0·082) and most of the genetic variation resided within patches. A pattern of isolation by distance was detected, suggesting that most of the gene flow occurred between neighbouring patches (≤1 km). The mean contemporary gene flow was 5 times higher than the historical estimate, and the correlation between them was very low. Moreover, the contemporary gene flow in roadsides was twice that in a nature reserve, and the correlation between contemporary and historical estimates was much higher in the nature reserve. Mowing of roadsides may contribute to the increase in contemporary gene flow. Simulations demonstrated that the higher contemporary gene flow could accelerate the process of transgene introgression in the metapopulation.
Conclusions Human disturbance such as mowing may alter gene flow patterns in wild populations, affecting the metapopulation dynamics of wild plants and the processes of transgene introgression in the metapopulation. The risk assessment and management of transgene introgression and the control of weeds need to take metapopulation dynamics into consideration.
Gibberellins (GAs) are a group of diterpene-type plant hormones biosynthesized from ent-kaurenoic acid via ent-kaurene. While the moss Physcomitrella patens has part of the GA biosynthetic pathway, from geranylgeranyl diphosphate to ent-kaurenoic acid, no GA is found in this species. Caulonemal differentiation in a P. patens mutant with a disrupted bifunctional ent-copalyl diphosphate synthase/ent-kaurene synthase (PpCPS/KS) gene is suppressed under red light, and is recovered by application of ent-kaurene and ent-kaurenoic acid. This indicates that derivatives of ent-kaurenoic acid, not GAs, might act as endogenous developmental regulators. Here, we found unique responses in the protonemal growth of P. patens under unilateral blue light, and these regulators were involved in the responses. When protonemata of the wild type were incubated under blue light, the chloronemal filaments grew in the opposite direction to the light source. Although this avoidance was not observed in the ent-kaurene deficient mutant, chloronemal growth toward a blue-light source in the mutant was suppressed by application of ent-kaurenoic acid, and the growth was rescued to that in the wild type. Expression analysis of the PpCPS/KS gene showed that the mRNA level under blue light was rapidly increased and was five times higher than under red light. These results suggest that regulators derived from ent-kaurenoic acid are strongly involved not only in the growth regulation of caulonemal differentiation under red light, but also in the light avoidance response of chloronemal growth under blue light. In particular, growth under blue light is regulated via thePpCPS/KS gene.
Modified lignin is easier to break apart, potentially leading to cheaper energy conversion.
The poplars in the greenhouse near John Ralph’s laboratory show no outward signs of weakness, but they have a secret soft spot. Thanks to genetic engineering, their wood contains an artificial molecule that makes it more easily dissolved by chemicals. It is the latest approach to a problem that has occupied the pulp, paper and biofuel industries for the past two decades — how to reduce the amount of energy it takes to break down the plants’ woody biomass.
Reporting today in Science1, Ralph, a biochemist at the University of Wisconsin–Madison, and his colleagues explain how they have designed poplars to make a form of lignin that breaks down more easily than naturally occurring forms. “The potential for saving energy is so high that this change should be considered in every plant that’s destined to be pulped or converted to biofuel,” says Ralph.
Ralph’s work follows decades of research on plants bred or engineered to make easily digestible lignin, or to simply grow less of it. Field trials have taken place in Belgium, France, Brazil, the United States, Sweden and Spain, says Wout Boerjan, who researches plant biotechnology at Ghent University in Belgium, and has conducted field trials on genetically modified poplar trees. Tricks employed have included turning down genes involved in lignin biosynthesis or tinkering with the proportions of the various molecular building blocks (monomers) that make up the lignin polymer2.
But interfering with lignin biosynthesis can stunt a plant’s growth or make it flop3. Scientists are attempting various solutions — three weeks ago, for example, researchers led by Clint Chapple at Purdue University in West Lafayette, Indiana, reported in Nature that they could knock out three genes in thale cress (Arabidopsis thaliana), yet produce easily digestible lignin4. Their engineered plant has not yet been tested in field trials.
Richard Dixon, another lignin researcher at the University of North Texas in Denton, says that there are other problems with engineered lignin. “Some plants with modified lignin behave as though they are under attack from pathogens and pests, even though they are not,” he says. This defence response could occur because the modified lignin causes a plant’s cell walls to release material — mimicking an invader’s breach of a cell.
“You can’t guarantee that anything you do to a plant doesn’t mess up something or other,” agrees Ralph. He hopes that his approach avoids these complications. He and his team have introduced a gene that causes the poplar to churn out an artificial component for the lignin polymer. As this molecule is incorporated into the growing lignin chain, it forms a type of chemical bond called an ester, which can be broken up by some chemicals at mild temperatures. The modified poplars seem to be healthy, and they produce normal amounts of lignin. But the researchers have yet to prove that the trees can thrive outside a greenhouse.
The team has not yet worked out how much the genetically engineered poplars could cut the costs of biofuel or paper production, says Ralph, but they have filed patent applications for the work, and are talking to pulp and paper firms.
Meanwhile, other researchers are working on chemicals that dissolve natural lignin5. If they are successful, transgenic plants — which could face regulatory complications — may take a back seat. So far, no plants with modified lignin are being commercialized, says Leslie Pearson, director of regulatory affairs at ArborGen, a company based in Ridgeville, South Carolina, that has run field trials of engineered plants in the United States and Brazil. But the company Forage Genetics International, based in West Salem, Wisconsin, is developing a genetically modified alfalfa plant that produces less woody lignin — allowing farmers to harvest more biomass for hay. The company hopes to have the alfalfa on the market by 2016.
Scientific Computing Computer Model Helps Breed Better Crops Scientific Computing This dream is coming closer to reality for University of Illinois at Urbana-Champaign researchers who have developed a new computer model that can help plant...
In the European Union (EU), genetically modified (GM) crops are regarded as a socially-sensitive technology. At present, GM crops are rarely cultivated in the EU and non-genetically modified ingredients dominate the EU market.
However, most consumers are unaware of the fact that many genetically modified ingredients (GMI) are present in EU supermarkets in spite of this virtual ban on GM. For example, eggs, meat or milk derived from GM-fed animals are marketed without a GM label.
Moreover, the EU political landscape has failed to create a stable and predictable environment in which to either implement or reject GM crops and their applications. As such, the present non-GM crop regime in the EU presents a tricky and challenging environment for agribusiness companies to determine their GM business policy.
Few academic studies have analysed this industry perspective on the current EU non-GM crop regime. In this paper, we therefore analyse which discourses influence the GM business policy of agribusiness companies that are active on the EU market and how these discourses influence the decision-making process of several agricultural industry sectors on whether to include or exclude GMIs in products for the EU market.
The paper outlines three discourses that shape the discursive space of GM crop applications in the EU from an industry perspective, (i) GMIs as an agricultural payoff; (ii) GMIs as a marketing threat; and (iii) non-GM crops as a preset end goal.
The paper also discusses how these discourses influence the GM business decision-making process for several agricultural industry sectors, these being the agricultural biotech industry, the compound feed industry, the food manufacturing and marketing industries, the potato industry and the organic farming sector. Accordingly, our research classifies the present non-GM crop regime in the EU as a “wicked problem”, due to the high level of conflict, discord and complexity involved...
GMO regulation is built on false premises in the EU and the Cartagena biosafety protocols.
Molecular processes of transgenesis and natural mutation are similar.
It is time to change GMO regulation toward a science based product oriented legislation.
Some legislations like the one from Canada rely on Novel crops, conventional or GMOs.
The regulation of genetically engineered crops, in Europe and within the legislation of the Cartagena biosafety protocol is built on false premises: The claim was (and unfortunately still is) that there is a basic difference between conventional and transgenic crops, this despite the fact that this has been rejected on scientifically solid grounds since many years. This contribution collects some major arguments for a fresh look at regulation of transgenic crops, they are in their molecular processes of creation not basically different from conventional crops, which are based in their breeding methods on natural, sometimes enhanced mutation. But the fascination and euphoria of the discoveries in molecular biology and the new perspectives in plant breeding in the sixties and seventies led to the wrong focus on transgenic plants alone. In a collective framing process the initial biosafety debates focused on the novelty of the process of transgenesis. When early debates on the risk assessment merged into legislative decisions, this wrong focus on transgenesis alone seemed uncontested. The process-focused view was also fostered by a conglomerate of concerned scientists and biotechnology companies, both with a vested interest to at least tolerate the rise of the safety threshold to secure research money and to discourage competitors of all kinds. Policy minded people and opponent activists without deeper insight in the molecular science agreed to those efforts without much resistance. It is interesting to realize, that the focus on processes was uncontested by a majority of regulators, this despite of serious early warnings from important authorities in science, mainly of US origin. It is time to change the regulation of genetically modified (GM) crops toward a more science based process — agnostic legislation. Although this article concentrates on the critique of the process-oriented regulation, including some details about the history behind, there should be no misunderstanding that there are other important factors responsible for the failure of this kind of process-oriented regulation, most importantly: the predominance of politics in the decision making processes combined with the lack of serious scientific debates on regulatory matters within the European Union and also in the Cartagena system, the obscure and much too complex decision making structures within the EU, and the active, professional, negative and intimidating role of fundamental opposition against GM crops on all levels dealing with flawed science, often declared as better parallel science published by ‘independent’ scientists.
Micronutrient malnutrition, characterized by insufficient intake levels of vitamins and minerals, is a major public health problem that affects about 2 billion people worldwide. In order to reduce the burden of this “hidden hunger”, biofortification is more and more being advocated as an alternative to current micronutrient interventions. Through enhancement of the micronutrient level of staple crops, it could address micronutrient malnutrition where the need is highest. Because staple crops are characterized by low micronutrient concentrations, genetic breeding techniques are often applied to increase levels of specific vitamins, such as folate and provitamin A. This study sheds light on the global status of micronutrient malnutrition, biofortification, and GM biofortified rice as both a GM food product with health benefits and a micronutrient intervention. Thereby, key consumer preference studies and cost-effectiveness analyses on Folate Biofortified Rice and Golden Rice are presented. Support is found for GM biofortified rice as a well-accepted GM food crop and a highly cost-effective health intervention.
Gravitropism, the slow reorientation of plant growth in response to gravity, is a key determinant of the form and posture of land plants. Shoot gravitropism is triggered when statocysts sense the local angle of the growing organ relative to the gravitational field. Lateral transport of the hormone auxin to the lower side is then enhanced, resulting in differential gene expression and cell elongation causing the organ to bend. However, little is known about the dynamics, regulation, and diversity of the entire bending and straightening process. Here, we modeled the bending and straightening of a rod-like organ and compared it with the gravitropism kinematics of different organs from 11 angiosperms. We show that gravitropic straightening shares common traits across species, organs, and orders of magnitude. The minimal dynamic model accounting for these traits is not the widely cited gravisensing law but one that also takes into account the sensing of local curvature, what we describe here as a graviproprioceptive law. In our model, the entire dynamics of the bending/straightening response is described by a single dimensionless “bending number” Bthat reflects the ratio between graviceptive and proprioceptive sensitivities. The parameter B defines both the final shape of the organ at equilibrium and the timing of curving and straightening. B can be estimated from simple experiments, and the model can then explain most of the diversity observed in experiments. Proprioceptive sensing is thus as important as gravisensing in gravitropic control, and the B ratio can be measured as phenotype in genetic studies.
Scientific American A Cassava Revolution Could Feed the World's Hungry Scientific American Because many cassava consumers live in developing countries, the plant has not received the intense breeding that has benefited crops more familiar to the...
Plant cell expansion is controlled by a fine-tuned balance between intracellular turgor pressure, cell wall loosening and cell wall biosynthesis. To understand these processes, it is important to gain in-depth knowledge of cell wall mechanics. Pollen tubes are tip-growing cells that provide an ideal system to study mechanical properties at the single cell level. With the available approaches it was not easy to measure important mechanical parameters of pollen tubes, such as the elasticity of the cell wall. We used a cellular force microscope (CFM) to measure the apparent stiffness of lily pollen tubes. In combination with a mechanical model based on the finite element method (FEM), this allowed us to calculate turgor pressure and cell wall elasticity, which we found to be around 0.3 MPa and 20–90 MPa, respectively. Furthermore, and in contrast to previous reports, we showed that the difference in stiffness between the pollen tube tip and the shank can be explained solely by the geometry of the pollen tube. CFM, in combination with an FEM-based model, provides a powerful method to evaluate important mechanical parameters of single, growing cells. Our findings indicate that the cell wall of growing pollen tubes has mechanical properties similar to rubber. This suggests that a fully turgid pollen tube is a relatively stiff, yet flexible cell that can react very quickly to obstacles or attractants by adjusting the direction of growth on its way through the female transmitting tissue.
The recent paper published in New Phytologist, Wang et al. (2014; this issue pp. 679–683), purports in its title that ‘A novel 5-enolpyruvoylshikimate-3-phosphate (EPSP) synthase transgene for glyphosate resistance stimulates growth and fecundity in weedy rice (Oryza sativa) without herbicide’ and in the paper claims that weedy rice expressing the transgene is more competitively fit than the wild type in the absence of glyphosate treatment. While this may be so, there is a lack of evidence in the paper that the transgene confers glyphosate resistance, or that the transgenic weedy rice is more competitively fit than its wild type. As this paper has generated extensive media coverage facilitated by the authors, we feel it imperative to analyze the paper in depth to ascertain whether the claims made in title, summary, and text have been met, whether criteria necessary for publication have been achieved, as well as whether the media reportage was justified in the form released by the authors.
The concept of pathogen-derived resistance has been employed for the development of transgenic papaya, using a coat protein-mediated, RNA-silencing mechanism and replicase gene-mediated transformation for effective PRSV disease management.