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GM Maize as Subsistence Crop: The South African Smallholder Experience - Gouse (2012) - AgBioForum

GM Maize as Subsistence Crop: The South African Smallholder Experience - Gouse (2012) - AgBioForum | plant cell genetics | Scoop.it

The South African smallholder GM maize experience has been—to date and internationally—the only example where a subsistence crop is produced by smallholder resource poor-farmers using GM seed. Their experience is thus of great interest, especially to African decision makers, international food and agricultural organizations, and the technology innovators. This article sheds light on eight years of research investigating the socio-economic impacts of GM maize adoption by smallholder farmers in South Africa. The main objective of the article is to highlight methodological and practical research challenges faced in this project in order to inform future socio-economic impact assessments and to contextualize research findings. Limited project findings are presented in the form of a discussion on the characteristics of early-adopting farmers and the yield impacts of GM maize adoption over the eight season period, emphasizing the variability between seasons and to show how methodological limitations impact research findings... Even though this study has limitations and the findings presented in this article are limited, it is possible to conclude that Hlabisa smallholder farmers highly value Bt and HT maize seed. Though seed availability might have played a role, by the final study season (2009/10), none of the farmers in the panel sample planted Bt, few still planted conventional maize, and the rest all planted HT or BR maize. Farmers seem to be willing to pay for the weed-control convenience; it appears as if farmers value the yield increase and (especially) the labor-saving benefit of HT maize more than the borer-control insurance of Bt maize. This inclination should be seen in the context of the relatively low borer pressure over the research period and the limited able-bodied labor force in rural KZN, caused by out-migration in search of employment, a high HIV/AIDS infection level, and elderly farmers. Future analyses and publications will focus on the labor-saving benefit of HT maize, potential expansion of production due to the decreased need for weeding labor, and gender implications of GM maize adoption and use.


Via Alexander J. Stein, Kwame Ogero
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Activation of Defense Mechanisms against Pathogens in Mosses and Fl... - PubMed - NCBI

Activation of Defense Mechanisms against Pathogens in Mosses and Fl... - PubMed - NCBI | plant cell genetics | Scoop.it
During evolution, plants have developed mechanisms to cope with and adapt to different types of stress, including microbial infection. Once the stress is sensed, signaling pathways are activated, leading to the induced expression of genes with different roles in defense. Mosses (Bryophytes) are non-vascular plants that diverged from flowering plants more than 450 million years ago, allowing comparative studies of the evolution of defense-related genes and defensive metabolites produced after microbial infection. The ancestral position among land plants, the sequenced genome and the feasibility of generating targeted knock-out mutants by homologous recombination has made the moss Physcomitrella patens an attractive model to perform functional studies of plant genes involved in stress responses. This paper reviews the current knowledge of inducible defense mechanisms in P. patens and compares them to those activated in flowering plants after pathogen assault, including the reinforcement of the cell wall, ROS production, programmed cell death, activation of defense genes and synthesis of secondary metabolites and defense hormones. The knowledge generated in P. patens together with comparative studies in flowering plants will help to identify key components in plant defense responses and to design novel strategies to enhance resistance to biotic stress.
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Genome Biology | Abstract | Organization and evolution of transposable elements along the bread wheat chromosome 3B

BackgroundThe 17 Gb bread wheat genome has massively expanded through the proliferation of transposable elements and two recent rounds of polyploidization. The assembly of a 774?Mb reference sequence of wheat chromosome 3B provided us with the opportunity to explore the impact of transposable elements (TEs) on the complex wheat genome structure and evolution at a resolution and scale never reached so far.ResultsWe develop an automated workflow, CLARI-TE, for TE modeling in complex genomes. We delineate precisely 56,488 intact and 196,391 fragmented TEs along the 3B pseudomolecule, accounting for 85% of the sequence, and reconstruct 30,199 nested insertions. TEs have been mostly silent for the last one million years, and the 3B chromosome has been shaped by a succession of bursts that occurred between 1 to 3 million years ago. Accelerated TE elimination in the high-recombination distal regions is a driving force towards chromosome partitioning. CACTAs overrepresented in the high-recombination distal regions are significantly associated with recently duplicated genes. In addition, we identify 140 CACTA-mediated gene capture events with 17 genes potentially created by exon shuffling and show that 19 captured genes are transcribed and under selection pressure, suggesting the important role of CACTAs in the recent wheat adaptation.ConclusionAccurate TE modeling uncovers the dynamics of TEs in a highly complex and polyploid genome. It provides novel insights into chromosome partitioning and highlights the role of CACTA transposons in the high level of gene duplication in wheat.
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Genetic transformation of moss Ceratodon purpureus by means of polycationic carriers of DNA - Springer

Genetic transformation of moss Ceratodon purpureus by means of polycationic carriers of DNA - Springer | plant cell genetics | Scoop.it
There is much progress in application of genetic engineering for improving the biological properties of different organisms. Viral and nonviral carriers are used for delivery of genetic material into target cells. Polymeric materials of natural and synthetic origin are the most promising gene delivery agents. These polymers demonstrated high efficiency of DNA delivery into animal cells, although they were not very effective in plant cells. Here, the procedure for genetic transformation of Ceratodon purpureus (Hedw.) Brid. moss protoplasts is described. The method is based on the application of surface-active polymeric carriers of the poly-DMAEM structure and controlled length and charge. This allows obtaining more transient and stable moss transformants per microgram of plasmid DNA when compared with known protocol based on using polyethyleneglycol. It is easier, more convenient, and cheaper than the “gene gun” method. Prospects for further improvement of structure and functional characteristics of new polymeric carriers are considered for delivery of genetic material into plant cells.
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The genome sequence of the orchid Phalaenopsis equestris : Nature Genetics : Nature Publishing Group

The genome sequence of the orchid Phalaenopsis equestris : Nature Genetics : Nature Publishing Group | plant cell genetics | Scoop.it
Zhong-Jian Liu, Lai-Qiang Huang, Yi-Bo Luo, Hong-Hwa Chen and Yves Van de Peer report the first genome sequence of a crassulacean acid metabolism (CAM) plant, the orchid Phalaenopsis equestris. They identify genes encoding CAM pathway enzymes and find that gene duplication was likely a key process in the evolution of CAM photosynthesis.
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An Env-derived multi-epitope HIV chimeric protein produced in the moss Physcomitrella patens is immunogenic in mice - Online First - Springer

An Env-derived multi-epitope HIV chimeric protein produced in the moss Physcomitrella patens is immunogenic in mice - Online First - Springer | plant cell genetics | Scoop.it
The need for economical and efficient platforms for vaccine production demands the exploration of emerging host organisms. In this study, the production of an antigenic protein is reported employing the moss Physcomitrella patens as an expression host. A multi-epitope protein from the Human Immunodeficiency Virus (HIV) based on epitopes from gp120 and gp41 was designed as a candidate subunit vaccine and named poly-HIV. Transgenic moss plants were generated carrying the corresponding poly-HIV transgene under a novel moss promoter and subsequently seven positive lines were confirmed by PCR. The poly-HIV protein accumulated up to 3.7 µg g−1 fresh weight in protonema cultures. Antigenic and immunogenic properties of the moss-produced recombinant poly-HIV are evidenced by Western blots and by mice immunization assays. The elicitation of specific antibodies in mice was observed, reflecting the immunogenic potential of this moss-derived HIV antigen. This is the first report on the production of a potential vaccine in the moss system and opens the avenue for glycoengineering approaches for the production of HIV human-like glycosylated antigens as well as other vaccine prototypes under GMP conditions in moss bioreactors.
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Unexpected Diversity of Feral Genetically Modified Oilseed Rape (Brassica napus L.) Despite a Cultivation and Import Ban in Switzerland

Unexpected Diversity of Feral Genetically Modified Oilseed Rape (Brassica napus L.) Despite a Cultivation and Import Ban in Switzerland | plant cell genetics | Scoop.it

Despite cultivation and seed import bans of genetically modified (GM) oilseed rape (Brassica napus L.), feral GM plants were found growing along railway lines and in port areas at four sites in Switzerland in 2011 and 2012. All GM plants were identified as glyphosate-resistant GM event GT73 (Roundup Ready, Monsanto). The most affected sites were the Rhine port of Basel and the St. Johann freight railway station in Basel. To assess the distribution and intra- and interspecific outcrossing of GM oilseed rape in more detail, we monitored these two sites in 2013. Leaves and seed pods of feral oilseed rape plants, their possible hybridization partners and putative hybrid plants were sampled in monthly intervals and analysed for the presence of transgenes by real-time PCR. Using flow cytometry, we measured DNA contents of cell nuclei to confirm putative hybrids. In total, 2787 plants were sampled. The presence of GT73 oilseed rape could be confirmed at all previously documented sampling locations and was additionally detected at one new sampling location within the Rhine port. Furthermore, we found the glufosinate-resistant GM events MS8xRF3, MS8 and RF3 (all traded as InVigor, Bayer) at five sampling locations in the Rhine port. To our knowledge, this is the first time that feral MS8xRF3, MS8 or RF3 plants were detected in Europe. Real-time PCR analyses of seeds showed outcrossing of GT73 into two non-GM oilseed rape plants, but no outcrossing of transgenes into related wild species was observed. We found no hybrids between oilseed rape and related species. GM plants most frequently occurred at unloading sites for ships, indicating that ship cargo traffic is the main entry pathway for GM oilseed rape. In the future, it will be of major interest to determine the source of GM oilseed rape seeds.


Via Christophe Jacquet
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Plasma Membrane-Targeted PIN Proteins Drive Shoot Development in a Moss: Current Biology

Plasma Membrane-Targeted PIN Proteins Drive Shoot Development in a Moss: Current Biology | plant cell genetics | Scoop.it

PIN proteins have polar plasma membrane localizations in the moss Physcomitrella
PIN-mediated auxin transport drives gametophytic shoot development in Physcomitrella
PIN-mediated auxin transport suppresses branching in Physcomitrella sporophytes

Plant body plans arise by the activity of meristematic growing tips during development and radiated independently in the gametophyte (n) and sporophyte (2n) stages of the life cycle during evolution. Although auxin and its intercellular transport by PIN family efflux carriers are primary regulators of sporophytic shoot development in flowering plants, the extent of conservation in PIN function within the land plants and the mechanisms regulating bryophyte gametophytic shoot development are largely unknown.

We have found that treating gametophytic shoots of the moss Physcomitrella patens with exogenous auxins and auxin transport inhibitors disrupts apical function and leaf development. Two plasma membrane-targeted PIN proteins are expressed in leafy shoots, and pin mutants resemble plants treated with auxins or auxin transport inhibitors. PIN-mediated auxin transport regulates apical cell function, leaf initiation, leaf shape, and shoot tropisms in moss gametophytes. pin mutant sporophytes are sometimes branched, reproducing a phenotype only previously seen in the fossil record and in rare natural moss variants.

Our results show that PIN-mediated auxin transport is an ancient, conserved regulator of shoot development.

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Frontiers | Metabolic engineering of the moss Physcomitrella patens to produce the sesquiterpenoids patchoulol and α/β-santalene | Plant Biotechnology

The moss Physcomitrella patens, has been genetically engineered to produce patchoulol and β-santalene, two valuable sesquiterpenoid ingredients in the fragrance industry. The highest yield of patchoulol achieved was 1.34 mg/g dry weight. This was achieved by non-targeted transformation of the patchoulol synthase and either a yeast or P. patens HMGR gene under the control of a 35S promoter. Santalene synthase targeted to the plastids yielded 0.039 mg/g dry weight of α/β santalene; cytosolic santalene synthase and 35S controlled HMGR afforded 0.022 mg/g dry weight. It has been observed that the final yield of the fragrance molecules is dependent on the expression of the synthase. This is the first report of heterologous production of sesquiterpenes in moss and it opens up a promising source for light-driven production of valuable fragrance ingredients.
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Do Political Attitudes Affect Consumer Choice? Evidence from a Large-Scale Field Study with Genetically Modified Bread in Switzerland

Do Political Attitudes Affect Consumer Choice? Evidence from a Large-Scale Field Study with Genetically Modified Bread in Switzerland | plant cell genetics | Scoop.it
Independent of the left-right model of ideological structure, genetically modified organisms (GMOs) in food and agriculture are resented across the political spectrum in Switzerland. In the absence of any real experience with genetically modified (GM) food but faced with continuous exposure to warning messages in the media, conditioned feelings related to such a politically sensitive product may have a significant influence on revealed consumer choice. In our large-scale field study, we examined this assumption by selling three types of bread labeled as ‘made with organic corn’, ‘made with genetically modified corn’ and ‘made with conventional corn’ respectively in five locations across Switzerland using different price scenarios and selling groups. Customers who decided to buy bread also received an envelope containing a questionnaire about their prior political attitude expressed through their voting decision in a national referendum on a five-year ban on GMOs in 2005. The results demonstrate that consumer purchase decisions are determined by contextual factors not captured by general political attitudes. Surprisingly, the mere presence of GM food did have a positive impact on overall sales. The assumption that consumers would feel turned off by the mere presence of GM food for political reasons can therefore be safely discarded.
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On the Origins of Agriculture

On the Origins of Agriculture | plant cell genetics | Scoop.it
This is the first in a series of posts reviewing the 17 articles found in the October 2014 Special Issue of American Journal of Botany, Speaking of Food: Connecting Basic and Applied Science. Agric...

Via Dorian Q Fuller, Loïc Lepiniec
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Dorian Q Fuller's curator insight, November 21, 7:42 AM

A blog summarizing the recent review on the archaeobotany of agricultural origins, aimed at bringing archaeobotany to a wider botanical audience, by archaeobotanists from Washington University in St Louis.

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#GMO The Precautionary Principle (with Application to the Genetic Modification of Organisms)

#GMO The Precautionary Principle (with Application to the Genetic Modification of Organisms) | plant cell genetics | Scoop.it

We present a non-naive version of the Precautionary (PP) that allows us to avoid paranoia and paralysis by confining precaution to specific domains and problems. PP is intended to deal with uncertainty and risk in cases where the absence of evidence and the incompleteness of scientific knowledge carries profound implications and in the presence of risks of "black swans", unforeseen and unforeseable events of extreme consequence. We formalize PP, placing it within the statistical and probabilistic structure of ruin problems, in which a system is at risk of total failure, and in place of risk we use a formal fragility based approach. We make a central distinction between 1) thin and fat tails, 2) Local and systemic risks and place PP in the joint Fat Tails and systemic cases. We discuss the implications for GMOs (compared to Nuclear energy) and show that GMOs represent a public risk of global harm (while harm from nuclear energy is comparatively limited and better characterized). PP should be used to prescribe severe limits on GMOs.

Jean-Pierre Zryd's insight:

The authors consider GMO as a high risk technology - Their article mentionned mostly if not only highly controversial and discredited GMO studies (Seralani among others) - This of course invalidate their conclusions.

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DNA Analysis of Herbarium Specimens of the Grass Weed Alopecurus myosuroides Reveals Herbicide Resistance Pre-Dated Herbicides

DNA Analysis of Herbarium Specimens of the Grass Weed Alopecurus myosuroides Reveals Herbicide Resistance Pre-Dated Herbicides | plant cell genetics | Scoop.it
Acetyl-CoA carboxylase (ACCase) alleles carrying one point mutation that confers resistance to herbicides have been identified in arable grass weed populations where resistance has evolved under the selective pressure of herbicides. In an effort to determine whether herbicide resistance evolves from newly arisen mutations or from standing genetic variation in weed populations, we used herbarium specimens of the grass weed Alopecurus myosuroides to seek mutant ACCase alleles carrying an isoleucine-to-leucine substitution at codon 1781 that endows herbicide resistance. These specimens had been collected between 1788 and 1975, i.e., prior to the commercial release of herbicides inhibiting ACCase. Among the 734 specimens investigated, 685 yielded DNA suitable for PCR. Genotyping the ACCase locus using the derived Cleaved Amplified Polymorphic Sequence (dCAPS) technique identified one heterozygous mutant specimen that had been collected in 1888. Occurrence of a mutant codon encoding a leucine residue at codon 1781 at the heterozygous state was confirmed in this specimen by sequencing, clearly demonstrating that resistance to herbicides can pre-date herbicides in weeds. We conclude that point mutations endowing resistance to herbicides without having associated deleterious pleiotropic effects can be present in weed populations as part of their standing genetic variation, in frequencies higher than the mutation frequency, thereby facilitating their subsequent selection by herbicide applications.
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Does polyploidy facilitate long-distance dispersal?

Does polyploidy facilitate long-distance dispersal? | plant cell genetics | Scoop.it

Background and Aims The ability of plant lineages to reach all continents contributes substantially to their evolutionary success. This is exemplified by the Poaceae, one of the most successful angiosperm families, in which most higher taxa (tribes, subfamilies) have global distributions. Due to the old age of the ocean basins relative to the major angiosperm radiations, this is only possible by means of long-distance dispersal (LDD), yet the attributes of lineages with successful LDD remain obscure. Polyploid species are over-represented in invasive floras and in the previously glaciated Arctic regions, and often have wider ecological tolerances than diploids; thus polyploidy is a candidate attribute of successful LDD.

Methods The link between polyploidy and LDD was explored in the globally distributed grass subfamily Danthonioideae. An almost completely sampled and well-resolved species-level phylogeny of the danthonioids was used, and the available cytological information was assembled. The cytological evolution in the clade was inferred using maximum likelihood (ML) as implemented in ChromEvol. The biogeographical evolution in the clade was reconstructed using ML and Bayesian approaches.

Key Results Numerous increases in ploidy level are demonstrated. A Late Miocene–Pliocene cycle of polyploidy is associated with LDD, and in two cases (the Australian Rytidosperma and the American Danthonia) led to secondary polyploidy. While it is demonstrated that successful LDD is more likely in polyploid than in diploid lineages, a link between polyploidization events and LDD is not demonstrated.

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A model system for analyzing intercellular communication through plasmodesmata using moss protonemata and leaves - Online First - Springer

A model system for analyzing intercellular communication through plasmodesmata using moss protonemata and leaves - Online First - Springer | plant cell genetics | Scoop.it

Plant growth, development, and environmental responses require the proper regulation of intercellular movement of signals and nutrients. For this, plants have specialized cytoplasmic channels, the plasmodesmata (PD), which allow the symplasmic movement of micro- and macromolecules between neighboring cells. Internal and external signals spatio-temporally regulate the movement of molecules through the PD to control plant development and environmental responses. Although some aspects of targeted movement of molecules have been revealed, the mechanisms of non-targeted, diffusible flow of molecules through PD, and its regulation and function, remain poorly understood, particularly at the cellular level. Previously, we developed a system to quantitatively analyze non-targeted movement of a photoconvertible fluorescent protein, Dendra2, at the single-cell level in the filamentous protonemata tissue of the moss Physcomitrella patens. In protonemata, one-dimensional intercellular communication can be easily observed and quantitatively analyzed at the cellular level. In this review, we describe how protonemata and leaves of P. patens can be used to study symplasmic movement through PD, and discuss how this system can help improve our understanding of PD regulation and function in development and environmental responses in plants.

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β-Carboxysomal proteins assemble into highly organized structures in Nicotiana chloroplasts - Lin - 2014 - The Plant Journal - Wiley Online Library

β-Carboxysomal proteins assemble into highly organized structures in Nicotiana chloroplasts - Lin - 2014 - The Plant Journal - Wiley Online Library | plant cell genetics | Scoop.it
The photosynthetic efficiency of C3 plants suffers from the reaction of ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) with O2 instead of CO2, leading to the costly process of photorespiration. Increasing the concentration of CO2 around Rubisco is a strategy used by photosynthetic prokaryotes such as cyanobacteria for more efficient incorporation of inorganic carbon. Engineering the cyanobacterial CO2-concentrating mechanism, the carboxysome, into chloroplasts is an approach to enhance photosynthesis or to compartmentalize other biochemical reactions to confer new capabilities on transgenic plants. We have chosen to explore the possibility of producing β-carboxysomes from Synechococcus elongatus PCC7942, a model freshwater cyanobacterium. Using the agroinfiltration technique, we have transiently expressed multiple β-carboxysomal proteins (CcmK2, CcmM, CcmL, CcmO and CcmN) in Nicotiana benthamiana with fusions that target these proteins into chloroplasts, and that provide fluorescent labels for visualizing the resultant structures. By confocal and electron microscopic analysis, we have observed that the shell proteins of the β-carboxysome are able to assemble in plant chloroplasts into highly organized assemblies resembling empty microcompartments. We demonstrate that a foreign protein can be targeted with a 17-amino-acid CcmN peptide to the shell proteins inside chloroplasts. Our experiments establish the feasibility of introducing carboxysomes into chloroplasts for the potential compartmentalization of Rubisco or other proteins.
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Optimization of crop productivity in tomato using induced mutations in the florigen pathway : Nature Genetics : Nature Publishing Group

Optimization of crop productivity in tomato using induced mutations in the florigen pathway : Nature Genetics : Nature Publishing Group | plant cell genetics | Scoop.it
Zachary Lippman and colleagues report the recovery in tomato of novel, chemically induced alleles in the SFT (florigen) gene and a newly identified suppressor of the SELF PRUNING gene. These alleles, in combination with previous florigen pathway mutations, allow for the quantitative fine-tuning of fruit yield, which may be applicable to other crop species.
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The beet Y locus encodes an anthocyanin MYB-like protein that activates the betalain red pigment pathway : Nature Genetics : Nature Publishing Group

The beet Y locus encodes an anthocyanin MYB-like protein that activates the betalain red pigment pathway : Nature Genetics : Nature Publishing Group | plant cell genetics | Scoop.it
Nearly all flowering plants produce red/violet anthocyanin pigments. Caryophyllales is the only order containing families that replace anthocyanins with unrelated red and yellow betalain pigments1, 2. Close biological correlation of pigmentation patterns suggested that betalains might be regulated by a conserved anthocyanin-regulating transcription factor complex consisting of a MYB, a bHLH and a WD repeat–containing protein (the MBW complex)3. Here we show that a previously uncharacterized anthocyanin MYB-like protein, Beta vulgaris MYB1 (BvMYB1), regulates the betalain pathway in beets. Silencing BvMYB1 downregulates betalain biosynthetic genes and pigmentation, and overexpressing BvMYB1 upregulates them. However, unlike anthocyanin MYBs, BvMYB1 will not interact with bHLH members of heterologous anthocyanin MBW complexes because of identified nonconserved residues. BvMYB1 resides at the historic beet pigment-patterning locus, Y, required for red-fleshed beets4. We show that Y and y express different levels of BvMYB1 transcripts. The co-option of a transcription factor regulating anthocyanin biosynthesis would be an important evolutionary event allowing betalains to largely functionally replace anthocyanins.
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The GMO case in France: Politics, lawlessness and postmodernism

The GMO case in France: Politics, lawlessness and postmodernism | plant cell genetics | Scoop.it
The GMO debacle in France is analyzed in the light of the balance of forces around this controversy, the changes in position of governments and the opponents’ strategic use of intimidation. These factors have caused insurmountable difficulties for scientific experimentations and assessment of the technology, as well as for farmers attempting to grow GM maize in this country. The change from a “modern” to a “postmodern” framing of official public debates and scientific institutions has not appeased confrontations concerning GMOs.
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Photoprotection of photosystems in fluctuating light intensities

Photoprotection of photosystems in fluctuating light intensities | plant cell genetics | Scoop.it
Oxygenic photosynthetic organisms experience strong fluctuations in light intensity in their natural terrestrial and aquatic growth environments. Recent studies with both plants and cyanobacteria have revealed that Photosystem (PS) I is the potential target of damage upon abrupt changes in light intensity. Photosynthetic organisms have, however, developed powerful mechanisms in order to protect their photosynthetic apparatus against such potentially hazardous light conditions. Although the electron transfer chain has remained relatively unchanged in both plant chloroplasts and their cyanobacterial ancestors, the photoprotective and regulatory mechanisms of photosynthetic light reactions have experienced conspicuous evolutionary changes. In cyanobacteria, the specific flavodiiron proteins (Flv1 and Flv3) are responsible for safeguarding PSI under rapidly fluctuating light intensities, whilst the thylakoid located terminal oxidases are involved in the protection of PSII during 12h diurnal cycles involving abrupt, square-wave, changes from dark to high light. Higher plants such as Arabidopsis thaliana have evolved different protective mechanisms. In particular, the PGR5 protein controls electron flow during sudden changes in light intensity by allowing the regulation mostly via the Cytochrome b6f complex. Besides the function of PGR5, plants have also acquired other dynamic regulatory mechanisms, among them the STN7-related LHCII protein phosphorylation that is similarly responsible for protection against rapid changes in the light environment. The green alga Chlamydomonas reinhardtii, as an evolutionary intermediate between cyanobacteria and higher plants, probably possesses both protective mechanisms. In this review, evolutionarily different photoprotective mechanisms under fluctuating light conditions are described and their contributions to cyanobacterial and plant photosynthesis are discussed.
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Agriculture facilitated permanent human occupation of the Tibetan Plateau after 3600 BP

Our understanding of when and how humans adapted to living at altitudes above 2000 to 3000 meters of the Tibetan Plateau has been constrained by a paucity of archaeological data. Here we report data sets from the northeastern Tibetan Plateau indicating that the first villages were established only by 5200 years ago. Since 3600 calendar years before the present, a novel agropastoral economy facilitated year-round living at higher altitudes. This successful subsistence strategy facilitated the adaptation of farmers-herders to the challenges of global temperature decline during the late Holocene.
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Forschungsarbeit "The German Beekeepers and Modern Plant Biotechnology" (english) von Klaus-Dieter Jany / Eberhard Höfer, Verlag Dr. Kovač, Hamburg 2015

Genetic engineering – an emotive issue in Germany. Only few topics in the agriculture and food sector are so emotionally and controversially discussed as modern plant biotechnology; the cultivation of genetically modified plants and their use as food or feed. Large circles of society are skeptical or fundamentally oppose the application of this technology. The reasons are manifold: ethical concerns, unforeseen risks to human and environment, threat of natural and organic farming and fears of economic loss. Parts of the beekeepers see in modern plant biotechnology a sustainable threat to their existence, and fear that the entry of pollen derived from genetically modified plants in honey reduces the acceptance of German honey amongst consumers and that Bt toxins affect the health of bees. The book presents a chronological overview of the fight and measures by beekeepers to enforce a ban on the cultivation of GM plants in Germany and to enforce a legal claim for compensation for economic losses caused by GM pollen in honey. The development of one simple compensation process and its transition to the European Court of Justice (ECJ) is shown and critically discussed. The ECJ judgment led to a revision of the EU-Honey Directive. As beekeepers did not feel adequately protected by the state, they carried out destructions of fields planted with GM crops as a means of civil disobedience. In the end, neither the processes nor the field destructions led to a ban of modern plant biotechnology or to a compensation claim or to a labeling of honey containing traces of GM pollen.

In the second part of the book, the scientific literature was analyzed regarding the impact of Bt toxins and Bt pollen on bee health. From the numerous scientific investigations and obtained results, no negative effect of Bt toxins / Bt-plants on the health of bees or bee mortality can be concluded.
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Speaking of food: Connecting basic and applied plant science

Speaking of food: Connecting basic and applied plant science | plant cell genetics | Scoop.it
The Food and Agriculture Organization (FAO) predicts that food production must rise 70% over the next 40 years to meet the demands of a growing population that is expected to reach nine billion by the year 2050. Many facets of basic plant science promoted by the Botanical Society of America are important for agriculture; however, more explicit connections are needed to bridge the gap between basic and applied plant research. This special issue, Speaking of Food: Connecting Basic and Applied Plant Science, was conceived to showcase productive overlaps of basic and applied research to address the challenges posed by feeding billions of people and to stimulate more research, fresh connections, and new paradigms. Contributions to this special issue thus illustrate some interactive areas of study in plant science—historical and modern plant–human interaction, crop and weed origins and evolution, and the effects of natural and artificial selection on crops and their wild relatives. These papers provide examples of how research integrating the basic and applied aspects of plant science benefits the pursuit of knowledge and the translation of that knowledge into actions toward sustainable production of crops and conservation of diversity in a changing climate.
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Maize Pests in Mexico and Challenges for the Adoption of Integrated Pest Management Programs

Mexico is the fifth largest maize producer and the area of origin and domestication of this crop. Mexico’s 6.8 million hectare annual production of maize represents 30% of its total domestic agricultural production and 6.6% of the country’s arable land. However, Mexico’s average yield of 3.17 tons per hectare is 38% below the world’s average. Although maize is a major crop globally, it is typically not grown under modern or comprehensive integrated pest management (IPM) programs aimed at minimizing economic damage and lowering environmental and health risks. Pest management in commercial maize in Mexico continues to rely primarily on chemical control using conventional synthetic insecticides. Approximately 3,000 tons of active ingredient per year are used to combat the single most important pest, the fall armyworm (Spodoptera frugiperda Smith), followed by the corn earworm (Helicoverpa zea Boddie) and the black cutworm (Agrotis ipsilon (Hufnagel)). Mexican farmers have successfully adopted IPM programs for many crops, but IPM is not common in maize crops. Although different components and elements have been identified, most of the information on maize pests and IPM in Mexico has been published in technical bulletins of a reduced regional scope or in difficult-to-access reports, generally describing laboratory screenings, preliminary field evaluations, or listing technical recommendations but rarely including products and practices that growers actually use. This report provides up-to-date information on the common pests in the main maize-growing areas of Mexico from experts in the field. Updated information on maize pest population dynamics and control has been gathered from agricultural professionals directly involved in maize crop protection. This critical information, not readably available for Mexican production systems, is intended to help researchers, government officials, and industry specialists in making decisions regarding time and resource allocations in the design and implementation of IPM techniques, practices, and programs for Mexican maize.
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Epigenetic reprogramming in plant sexual reproduction : Nature Reviews Genetics : Nature Publishing Group

Epigenetic reprogramming in plant sexual reproduction : Nature Reviews Genetics : Nature Publishing Group | plant cell genetics | Scoop.it
Epigenetic reprogramming consists of global changes in DNA methylation and histone modifications. In mammals, epigenetic reprogramming is primarily associated with sexual reproduction and occurs during both gametogenesis and early embryonic development. Such reprogramming is crucial not only to maintain genomic integrity through silencing transposable elements but also to reset the silenced status of imprinted genes. In plants, observations of stable transgenerational inheritance of epialleles have argued against reprogramming. However, emerging evidence supports that epigenetic reprogramming indeed occurs during sexual reproduction in plants and that it has a major role in maintaining genome integrity and a potential contribution to epiallelic variation.
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Agroecological Research: Conforming—or Transforming the Dominant Agro-Food Regime?

Agroecological Research: Conforming—or Transforming the Dominant Agro-Food Regime? | plant cell genetics | Scoop.it
Agroecology has three practical forms—a scientific discipline, an agricultural practice, and a social movement. Their integration has provided a collective-action mode for contesting the dominant agro-food regime and creating alternatives, especially through a linkage with food sovereignty. At the same time, agroecology has been recently adopted by some actors who also promote conventional agriculture. Agroecology can play different roles—either conforming to the dominant regime, or else helping to transform it—contingent on specific empowerment strategies. Tensions between “conform versus transform” roles can be identified in European agroecological research, especially in three areas: farm-level agroecosystems development; participatory plant breeding; and short food-supply chains remunerating agroecological methods. To play a transformative role, collaborative strategies need to go beyond the linear stereotype whereby scientists “transfer” technology or farmers “apply” scientific research results. To the extent that farmer–scientist alliances co-create and exchange knowledge, such gains can transform the research system.
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