Plant Gene Seeker -PGS
8.1K views | +0 today
 
Scooped by Andres Zurita
onto Plant Gene Seeker -PGS
Scoop.it!

Plant Callus: Mechanisms of Induction and Repression

Plant Callus: Mechanisms of Induction and Repression | Plant Gene Seeker -PGS | Scoop.it
Andres Zurita's insight:

Plants develop unorganized cell masses like callus and tumors in response to various biotic and abiotic stimuli. Since the historical discovery that the combination of two growth-promoting hormones, auxin and cytokinin, induces callus from plant explants in vitro, this experimental system has been used extensively in both basic research and horticultural applications. The molecular basis of callus formation has long been obscure, but we are finally beginning to understand how unscheduled cell proliferation is suppressed during normal plant development and how genetic and environmental cues override these repressions to induce callus formation. In this review, we will first provide a brief overview of callus development in nature and in vitro and then describe our current knowledge of genetic and epigenetic mechanisms underlying callus formation.


OPEN

more...
No comment yet.
Plant Gene Seeker -PGS
Absolutely Fascinated for plant & genomes
Curated by Andres Zurita
Your new post is loading...
Your new post is loading...
Scooped by Andres Zurita
Scoop.it!

Genome resources for climate‐resilient cowpea, an essential crop for food security

Genome resources for climate‐resilient cowpea, an essential crop for food security | Plant Gene Seeker -PGS | Scoop.it
Cowpea (Vigna unguiculata L. Walp.) is a legume crop that is resilient to hot and drought-prone climates, and a primary source of protein in sub-Saharan Africa and other parts of the developing world. However, genome resources for cowpea have lagged behind most other major crops. Here we describe foundational genome resources and their application to the analysis of germplasm currently in use in West African breeding programs. Resources developed from the African cultivar IT97K-499-35 include a whole-genome shotgun (WGS) assembly, a bacterial artificial chromosome (BAC) physical map, and assembled sequences from 4355 BACs. These resources and WGS sequences of an additional 36 diverse cowpea accessions supported the development of a genotyping assay for 51 128 SNPs, which was then applied to five bi-parental RIL populations to produce a consensus genetic map containing 37 372 SNPs. This genetic map enabled the anchoring of 100 Mb of WGS and 420 Mb of BAC sequences, an exploration of genetic diversity along each linkage group, and clarification of macrosynteny between cowpea and common bean. The SNP assay enabled a diversity analysis of materials from West African breeding programs. Two major subpopulations exist within those materials, one of which has significant parentage from South and East Africa and more diversity. There are genomic regions of high differentiation between subpopulations, one of which coincides with a cluster of nodulin genes. The new resources and knowledge help to define goals and accelerate the breeding of improved varieties to address food security issues related to limited-input small-holder farming and climate stress.
more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

Dancing in the dark: darkness as a signal in plants

Dancing in the dark: darkness as a signal in plants | Plant Gene Seeker -PGS | Scoop.it

Daily cycles of light and dark provide an organizing principle and temporal constraints under which life on Earth evolved. While light is often the focus of plant studies, it is only half the story. Plants continuously adjust to their surroundings, taking both dawn and dusk as cues to organize their growth, development and metabolism to appropriate times of day. In this review, we examine the effects of darkness on plant physiology and growth. We describe the similarities and differences between seedlings grown in the dark versus those grown in light–dark cycles, and the evolution of etiolated growth. We discuss the integration of the circadian clock into other processes, looking carefully at the points of contact between clock genes and growth-promoting gene-regulatory networks in temporal gating of growth. We also examine daily starch accumulation and degradation, and the possible contribution of dark-specific metabolic controls in regulating energy and growth. Examining these studies together reveals a complex and continuous balancing act, with many signals, dark included, contributing information and guiding the plant through its life cycle. The extraordinary interconnection between light and dark is manifest during cycles of day and night and during seedling emergence above versus below the soil surface.

more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

The Key to Mn Homeostasis in Plants: Regulation of Mn Transporters

The Key to Mn Homeostasis in Plants: Regulation of Mn Transporters | Plant Gene Seeker -PGS | Scoop.it

Plants only require small amounts of manganese (Mn) for healthy growth, but Mn concentrations in soil solution vary from sub-micromolar to hundreds of micromolar across the growth
period. Therefore, plants must deal with large Mn concentration fluctuations, but the molecular mechanisms underlying how plants cope with low and high Mn concentrations are poorly understood. In this Opinion we discuss the role of Mn transporters in the
uptake, distribution, and detoxification of Mn in response to changes in Mn concentrations through their regulation at the transcriptional and protein levels, mainly focusing on rice, an Mn-tolerant and −accumulating species.

more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

Arabidopsis Root-Type Ferredoxin:NADP(H) Oxidoreductase 2 is Involved in Detoxification of Nitrite in Roots | Plant and Cell Physiology | Oxford Academic

Arabidopsis Root-Type Ferredoxin:NADP(H) Oxidoreductase 2 is Involved in Detoxification of Nitrite in Roots | Plant and Cell Physiology | Oxford Academic | Plant Gene Seeker -PGS | Scoop.it
Ferredoxin:NADP(H) oxidoreductase (FNR) plays a key role in redox metabolism in plastids. Whereas leaf FNR (LFNR) is required for photosynthesis, root FNR (RFNR) is believed to provide electrons to ferredoxin (Fd)-dependent enzymes, including nitrite reductase (NiR) and Fd-glutamine-oxoglutarate aminotransferase (Fd-GOGAT) in non-photosynthetic conditions. In some herbal species, however, most nitrate reductase activity is located in photosynthetic organs, and ammonium in roots is assimilated mainly by Fd-independent NADH-GOGAT. Therefore, RFNR might have a limited impact on N assimilation in roots grown with nitrate or ammonium nitrogen sources. AtRFNR genes are rapidly induced by application of toxic nitrite. Thus, we tested the hypothesis that RFNR could contribute to nitrite reduction in roots by comparing Arabidopsis thaliana seedlings of the wild type with loss-of-function mutants of RFNR2. When these seedlings were grown under nitrate, nitrite or ammonium, only nitrite nutrition caused impaired growth and nitrite accumulation in roots of rfnr2. Supplementation of nitrite with nitrate or ammonium as N sources did not restore the root growth in rfnr2. Also, a scavenger for nitric oxide (NO) could not effectively rescue the growth impairment. Thus, nitrite toxicity, rather than N depletion or nitrite-dependent NO production, probably causes the rfnr2 root growth defect. Our results strongly suggest that RFNR2 has a major role in reduction of toxic nitrite in roots. A specific set of genes related to nitrite reduction and the supply of reducing power responded to nitrite concomitantly, suggesting that the products of these genes act co-operatively with RFNR2 to reduce nitrite in roots.
more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

The endodermis as a checkpoint for nutrients

The endodermis as a checkpoint for nutrients | Plant Gene Seeker -PGS | Scoop.it

Plant roots forage the soil for nutrients and transport them upwards to the aerial parts. Nutrients entering the plant are transported through the concentric layers of epidermis, cortex and endodermis before reaching the central vasculature. The endodermis is the innermost cortical cell layer that surrounds the vasculature. The endodermis forms barriers, the Casparian strips and suberin lamellae, which have been assumed to play a major role in controlling nutrient acquisition. However, the molecular network controlling its differentiation has started to be investigated only recently, giving an unprecedented opportunity to address the role of these barriers in plant nutrition. This insight aims to present recent advances regarding endodermis differentiation, its function as a barrier for nutrients and its developmental plasticity, all pointing to a pivotal role of the endodermis as a checkpoint for nutrients.

more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

AVP1: One Protein, Many Roles

AVP1: One Protein, Many Roles | Plant Gene Seeker -PGS | Scoop.it
Constitutive expression of the Arabidopsis vacuolar proton-pumping pyrophosphatase (H+-PPase) gene (AVP1) increases plant growth under various abiotic stress conditions and, importantly, under nonstressed conditions. Many interpretations have been proposed to explain these phenotypes, including greater vacuolar ion sequestration, increased auxin transport, enhanced heterotrophic growth, and increased transport of sucrose from source to sink tissues. In this review, we evaluate all the roles proposed for AVP1, using findings published to date from mutant plants lacking functional AVP1 and transgenic plants expressing AVP1. It is clear that AVP1 is one protein with many roles, and that one or more of these roles act to enhance plant growth. The complexity suggests that a systems biology approach to evaluate biological networks is required to investigate these intertwined roles.
more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

Frontiers | New Insights on Plant Salt Tolerance Mechanisms and Their Potential Use for Breeding | Crop Science and Horticulture

Frontiers | New Insights on Plant Salt Tolerance Mechanisms and Their Potential Use for Breeding | Crop Science and Horticulture | Plant Gene Seeker -PGS | Scoop.it
Soil salinization is a major threat to agriculture in arid and semi-arid regions, where water scarcity and inadequate drainage of irrigated lands severely reduce crop yield. Salt accumulation inhibits plant growth and reduces the ability to uptake water and nutrients, leading to osmotic or water-deficit stress. Salt is also causing injury of the young photosynthetic leaves and acceleration of their senescence, as the Na+ cation is toxic when accumulating in cell cytosol resulting in ionic imbalance and toxicity of transpiring leaves. To cope with salt stress, plants have evolved mainly two types of tolerance mechanisms based on either limiting the entry of salt by the roots, or controlling its concentration and distribution. Understanding the overall control of Na+ accumulation and functional studies of genes involved in transport processes, will provide a new opportunity to improve the salinity tolerance of plants relevant to food security in arid regions. A better understanding of these tolerance mechanisms can be used to breed crops with improved yield performance under salinity stress. Moreover, associations of cultures with nitrogen-fixing bacteria and arbuscular mycorrhizal fungi could serve as an alternative and sustainable strategy to increase crop yields in salt-affected fields.
more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

Time of day determines Arabidopsis transcriptome and growth dynamics under mild drought

Time of day determines Arabidopsis transcriptome and growth dynamics under mild drought | Plant Gene Seeker -PGS | Scoop.it

Drought stress is a major problem for agriculture worldwide, causing significant yield losses. Plants have developed highly flexible mechanisms to deal with drought, including organ- and developmental stage-specific responses. In young leaves, growth is repressed as an active mechanism to save water and energy, increasing the chances of survival but decreasing yield. Despite its importance, the molecular basis for this growth inhibition is largely unknown. Here, we present a novel approach to explore early molecular mechanisms controlling Arabidopsis leaf growth inhibition following mild drought. We found that growth and transcriptome responses to drought are highly dynamic. Growth was only repressed by drought during the day, and our evidence suggests that this may be due to gating by the circadian clock. Similarly, time of day strongly affected the extent, specificity, and in certain cases even direction of drought-induced changes in gene expression. These findings underscore the importance of taking into account diurnal patterns to understand stress responses, as only a small core of drought-responsive genes are affected by drought at all times of the day. Finally, we leveraged our high-resolution data to demonstrate that phenotypic and transcriptome responses can be matched to identify putative novel regulators of growth under mild drought.

more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

Evaluating physiological responses of plants to salinity stress

Evaluating physiological responses of plants to salinity stress | Plant Gene Seeker -PGS | Scoop.it

Background 

Because soil salinity is a major abiotic constraint affecting crop yield, much research has been conducted to develop plants with improved salinity tolerance. Salinity stress impacts many aspects of a plant’s physiology, making it difficult to study in toto. Instead, it is more tractable to dissect the plant’s response into traits that are hypothesized to be involved in the overall tolerance of the plant to salinity. 

Scope and conclusions 

We discuss how to quantify the impact of salinity on different traits, such as relative growth rate, water relations, transpiration, transpiration use efficiency, ionic relations, photosynthesis, senescence, yield and yield components. We also suggest some guidelines to assist with the selection of appropriate experimental systems, imposition of salinity stress, and obtaining and analysing relevant physiological data using appropriate indices. We illustrate how these indices can be used to identify relationships amongst the proposed traits to identify which traits are the most important contributors to salinity tolerance. Salinity tolerance is complex and involves many genes, but progress has been made in studying the mechanisms underlying a plant’s response to salinity. Nevertheless, several previous studies on salinity tolerance could have benefited from improved experimental design. We hope that this paper will provide pertinent information to researchers on performing proficient assays and interpreting results from salinity tolerance experiments.

more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

50 years of Arabidopsis research: highlights and future directions

50 years of Arabidopsis research: highlights and future directions | Plant Gene Seeker -PGS | Scoop.it

The year 2014 marked the 25th International Conference on Arabidopsis Research. In the 50 yr since the first International Conference on Arabidopsis Research, held in 1965 in Göttingen, Germany, > 54 000 papers that mention Arabidopsis thaliana in the title, abstract or keywords have been published. We present herein a citational network analysis of these papers, and touch on some of the important discoveries in plant biology that have been made in this powerful model system, and highlight how these discoveries have then had an impact in crop species. We also look to the future, highlighting some outstanding questions that can be readily addressed in Arabidopsis. Topics that are discussed include Arabidopsis reverse genetic resources, stock centers, databases and online tools, cell biology, development, hormones, plant immunity, signaling in response to abiotic stress, transporters, biosynthesis of cells walls and macromolecules such as starch and lipids, epigenetics and epigenomics, genome-wide association studies and natural variation, gene regulatory networks, modeling and systems biology, and synthetic biology.

more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

DNA-Free Genetically Edited Grapevine and Apple Protoplast Using CRISPR/Cas9 Ribonucleoproteins | Technical Advances in Plant Science

DNA-Free Genetically Edited Grapevine and Apple Protoplast Using CRISPR/Cas9 Ribonucleoproteins | Technical Advances in Plant Science | Plant Gene Seeker -PGS | Scoop.it
The combined availability of whole genome sequences and genome editing tools is set to revolutionize the field of fruit biotechnology by enabling the introduction of targeted genetic changes with unprecedented control and accuracy, both to explore emergent phenotypes and to introduce new functionalities. Although plasmid-mediated delivery of genome editing components to plant cells is very efficient, it also presents some drawbacks, such as possible random integration of plasmid sequences in the host genome. Additionally, it may well be intercepted by current process-based GMO regulations, complicating the path to commercialization of improved varieties. Here, we explore direct delivery of purified CRISPR/Cas9 ribonucleoproteins (RNPs) to the protoplast of grape cultivar Chardonnay and apple cultivar such as Golden delicious fruit crop plants for efficient targeted mutagenesis. We targeted MLO-7, a susceptible gene in order to increase resistance to powdery mildew in grape cultivar and DIPM-1, DIPM-2, and DIPM-4 in the apple to increase resistance to fire blight disease. Furthermore, efficient protoplast transformation, the molar ratio of Cas9 and sgRNAs were optimized for each grape and apple cultivar. The targeted mutagenesis insertion and deletion rate was analyzed using targeted deep sequencing. Our results demonstrate that direct delivery of CRISPR/Cas9 RNPs to the protoplast system enables targeted gene editing and paves the way to the generation of DNA-free genome edited grapevine and apple plants.
more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

Overexpression of PP2A‐C5 that encodes the catalytic subunit 5 of protein phosphatase 2A in Arabidopsis confers better root and shoot development under salt conditions

Overexpression of PP2A‐C5 that encodes the catalytic subunit 5 of protein phosphatase 2A in Arabidopsis confers better root and shoot development under salt conditions | Plant Gene Seeker -PGS | Scoop.it
Protein phosphatase 2A (PP2A) is an enzyme consisting of three subunits: a scaffolding A subunit, a regulatory B subunit and a catalytic C subunit. PP2As were shown to play diverse roles in eukaryotes. In this study, the function of the Arabidopsis PP2A-C5 gene that encodes the catalytic subunit 5 of PP2A was studied using both loss-of-function and gain-of-function analyses. Loss-of-function mutant pp2a-c5-1 displayed more impaired growth during root and shoot development, whereas overexpression of PP2A-C5 conferred better root and shoot growth under different salt treatments, indicating that PP2A-C5 plays an important role in plant growth under salt conditions. Double knockout mutants of pp2a-c5-1 and salt overly sensitive (sos) mutants sos1-1, sos2-2 or sos3-1 showed additive sensitivity to NaCl, indicating that PP2A-C5 functions in a pathway different from the SOS signalling pathway. Using yeast two-hybrid analysis, four vacuolar membrane chloride channel (CLC) proteins, AtCLCa, AtCLCb, AtCLCc and AtCLCg, were found to interact with PP2A-C5. Moreover, overexpression of AtCLCc leads to increased salt tolerance and Cl− accumulation in transgenic Arabidopsis plants. These data indicate that PP2A-C5-mediated better growth under salt conditions might involve up-regulation of CLC activities on vacuolar membranes and that PP2A-C5 could be used for improving salt tolerance in crops.
more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

How many ways are there to make a root?

How many ways are there to make a root? | Plant Gene Seeker -PGS | Scoop.it

Highlights 

• Plants produce highly conserved root structures from diverse tissue origins. 

• Many early programs for induction of roots are specific to developmental contexts. 

• Late stage patterning is regulated by homologous if not identical genes. 

• Auxin–cytokinin interactions play a fundamental role in tissue patterning stages. 

• It is not clear if universal signaling ‘rules’ organize a generic root body plan. 


Plants often make the same organ in different development contexts. Roots are a quintessential example, with embryonic, primary, lateral, adventitious, and regenerative roots common to many plants. The cellular origins and early morphologies of different roots can vary greatly, but the adult structures can be remarkably similar. Recent studies have highlighted the diversity of mechanisms that can initiate roots while late patterning mechanisms are frequently shared. In the middle stages when patterning emerges, evidence shows that antagonistic auxin–cytokinin interactions regulate tissue patterns in root embryogenesis, vascular organization, and regeneration but it is not yet clear if a common ontogeny for the root body plan exists.

more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

The pangenome of hexaploid bread wheat

The pangenome of hexaploid bread wheat | Plant Gene Seeker -PGS | Scoop.it
There is an increasing understanding that gene presence absence variation plays an important role in the heritability of agronomic traits, however there have been relatively few studies on gene presence absence variation in crop species. Hexaploid wheat is one of the most important food crops in the world and intensive breeding has reduced the genetic diversity of elite cultivars. Major efforts have produced draft genome assemblies for the cultivar Chinese Spring, but it is unknown how well this represents the genome diversity found in current modern elite cultivars. In this study we build an improved reference for Chinese Spring and explore gene diversity across 18 wheat cultivars. We predict a pangenome size of 140,500 +/- 102 genes, a core genome of 81,070 +/- 1,631 genes, and an average of 128,656 genes in each cultivar. Functional annotation of the variable gene set suggests that it is enriched for genes that may be associated with important agronomic traits. In addition to gene presence variation, more than 36 million intervarietal SNPs were identified across the pangenome. This study of the wheat pangenome provides insight into elite wheat genome diversity as a basis for genomics based improvement of this important crop. A wheat pangenome Gbrowse is available at http://appliedbioinformatics.com.au/cgi-bin/gb2/gbrowse/WheatPan/, and data is available for download from http://wheatgenome.info/wheat_genome_databases.php.
more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

Chloride on the Move

Chloride on the Move | Plant Gene Seeker -PGS | Scoop.it

Chloride (Cl−) is an essential plant nutrient but under saline conditions it can accumulate to toxic levels in leaves; limiting this accumulation improves the salt tolerance of some crops. The rate-limiting step for this process – the transfer of Cl− from root symplast to xylem apoplast, which can antagonize delivery of the macronutrient nitrate (NO3−) to shoots – is regulated by abscisic acid (ABA) and is multigenic.
Until recently the molecular mechanisms underpinning this salt-tolerance trait were poorly defined.

more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

Ethnobotany, Phylogeny, and ‘Omics’ for Human Health and Food Security

Ethnobotany, Phylogeny, and ‘Omics’ for Human Health and Food Security | Plant Gene Seeker -PGS | Scoop.it
Here, we propose a new term, ‘ethnobotanical convergence’, to refer to the similar uses for plants included in the same node of a phylogeny. This phylogenetic approach, together with the ‘omics’ revolution, shows how combining modern technologies with traditional ethnobotanical knowledge could be used to identify potential new applications of plants.
more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

The genome of Chenopodium quinoa : Nature Research

The genome of Chenopodium quinoa : Nature Research | Plant Gene Seeker -PGS | Scoop.it
Chenopodium quinoa (quinoa) is a highly nutritious grain identified as an important crop to improve world food security. Unfortunately, few resources are available to facilitate its genetic improvement. Here we report the assembly of a high-quality, chromosome-scale reference genome sequence for quinoa, which was produced using single-molecule real-time sequencing in combination with optical, chromosome-contact and genetic maps. We also report the sequencing of two diploids from the ancestral gene pools of quinoa, which enables the identification of sub-genomes in quinoa, and reduced-coverage genome sequences for 22 other samples of the allotetraploid goosefoot complex. The genome sequence facilitated the identification of the transcription factor likely to control the production of anti-nutritional triterpenoid saponins found in quinoa seeds, including a mutation that appears to cause alternative splicing and a premature stop codon in sweet quinoa strains. These genomic resources are an important first step towards the genetic improvement of quinoa.
more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

Dissecting the Biochemical and Transcriptomic Effects of a Locally Applied Heat Treatment on Developing Cabernet Sauvignon Grape Berries

Dissecting the Biochemical and Transcriptomic Effects of a Locally Applied Heat Treatment on Developing Cabernet Sauvignon Grape Berries | Plant Gene Seeker -PGS | Scoop.it
Reproductive development of grapevine and berry composition are both strongly influenced by temperature. To date, the molecular mechanisms involved in grapevine berries response to high temperatures are poorly understood. Unlike recent data that addressed the effects on berry development of elevated temperatures applied at the whole plant level, the present work particularly focuses on the fruit responses triggered by direct exposure to heat treatment (HT). In the context of climate change, this work focusing on temperature effect at the microclimate level is of particular interest as it can help to better understand the consequences of leaf removal (a common viticultural practice) on berry development. HT (+ 8°C) was locally applied to clusters from Cabernet Sauvignon fruiting cuttings at three different developmental stages (middle green, véraison and middle ripening). Samples were collected 1, 7 and 14 days after treatment and used for metabolic and transcriptomic analyses. The results showed dramatic and specific biochemical and transcriptomic changes in heat exposed berries, depending on the developmental stage and the stress duration. When applied at the herbaceous stage, HT delayed the onset of véraison. Heating also strongly altered the berry concentration of amino acids and organic acids (e.g. phenylalanine, γ-aminobutyric acid and malate) and decreased the anthocyanin content at maturity. These physiological alterations could be partly explained by the deep remodelling of transcriptome in heated berries. More than 7000 genes were deregulated in at least one of the nine experimental conditions. The most affected processes belong to the categories “stress responses”, “protein metabolism” and “secondary metabolisms”, highlighting the intrinsic capacity of grape berries to perceive HT and to build adaptive responses. Additionally, important changes in processes related to “transport”, “hormone” and “cell wall” might contribute to the postponing of véraison. Finally, opposite effects depending on heating duration were observed for genes encoding enzymes of the general phenylpropanoid pathway, suggesting that the HT-induced decrease in anthocyanin content may result from a combination of transcript abundance and product degradation.
more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

Frontiers | Biostimulants in Plant Science: A Global Perspective

Frontiers | Biostimulants in Plant Science: A Global Perspective | Plant Gene Seeker -PGS | Scoop.it
This review presents a comprehensive and systematic study of the field of plant biostimulants and considers the fundamental and innovative principles underlying this technology. The elucidation of the biological basis of biostimulant function is a prerequisite for the development of science-based biostimulant industry and sound regulations governing these compounds. The task of defining the biological basis of biostimulants as a class of compounds, however, is made more complex by the diverse sources of biostimulants present in the market, which include bacteria, fungi, seaweeds, higher plants, animals and humate-containing raw materials, and the wide diversity of industrial processes utilized in their preparation. To distinguish biostimulants from the existing legislative product categories we propose the following definition of a biostimulant as ‘a formulated product of biological origin that improves plant productivity as a consequence of the novel or emergent properties of the complex of constituents, and not as a sole consequence of the presence of known essential plant nutrients, plant growth regulators, or plant protective compounds’. The definition provided here is important as it emphasizes the principle that biological function can be positively modulated through application of molecules, or mixtures of molecules, for which an explicit mode of action has not been defined. Given the difficulty in determining a ‘mode of action’ for a biostimulant, and recognizing the need for the market in biostimulants to attain legitimacy, we suggest that the focus of biostimulant research and validation should be upon proof of efficacy and safety and the determination of a broad mechanism of action, without a requirement for the determination of a specific mode of action. While there is a clear commercial imperative to rationalize biostimulants as a discrete class of products, there is also a compelling biological case for the science-based development of, and experimentation with biostimulants in the expectation that this may lead to the identification of novel biological molecules and phenomenon, pathways and processes, that would not have been discovered if the category of biostimulants did not exist, or was not considered legitimate.
more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

Genetic architecture of plant stress resistance: multi‐trait genome‐wide association mapping

Genetic architecture of plant stress resistance: multi‐trait genome‐wide association mapping | Plant Gene Seeker -PGS | Scoop.it

Plants are exposed to combinations of various biotic and abiotic stresses, but stress responses are usually investigated for single stresses only. 

Here, we investigated the genetic architecture underlying plant responses to 11 single stresses and several of their combinations by phenotyping 350 Arabidopsis thaliana accessions. A set of 214 000 single nucleotide polymorphisms (SNPs) was screened for marker-trait associations in genome-wide association (GWA) analyses using tailored multi-trait mixed models. 

Stress responses that share phytohormonal signaling pathways also share genetic architecture underlying these responses. After removing the effects of general robustness, for the 30 most significant SNPs, average quantitative trait locus (QTL) effect sizes were larger for dual stresses than for single stresses. 

Plants appear to deploy broad-spectrum defensive mechanisms influencing multiple traits in response to combined stresses. Association analyses identified QTLs with contrasting and with similar responses to biotic vs abiotic stresses, and below-ground vs above-ground stresses.

Our approach allowed for an unprecedented comprehensive genetic analysis of how plants deal with a wide spectrum of stress conditions.

more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

Towards an open grapevine information system

Towards an open grapevine information system | Plant Gene Seeker -PGS | Scoop.it
Viticulture, like other fields of agriculture, is currently facing important challenges that will be addressed only through sustained, dedicated and coordinated research. Although the methods used in biology have evolved tremendously in recent years and now involve the routine production of large data sets of varied nature, in many domains of study, including grapevine research, there is a need to improve the findability, accessibility, interoperability and reusability (FAIR-ness) of these data. Considering the heterogeneous nature of the data produced, the transnational nature of the scientific community and the experience gained elsewhere, we have formed an open working group, in the framework of the International Grapevine Genome Program (www.vitaceae.org), to construct a coordinated federation of information systems holding grapevine data distributed around the world, providing an integrated set of interfaces supporting advanced data modeling, rich semantic integration and the next generation of data mining tools. To achieve this goal, it will be critical to develop, implement and adopt appropriate standards for data annotation and formatting. The development of this system, the GrapeIS, linking genotypes to phenotypes, and scientific research to agronomical and oeneological data, should provide new insights into grape biology, and allow the development of new varieties to meet the challenges of biotic and abiotic stress, environmental change, and consumer demand.
more...
No comment yet.
Rescooped by Andres Zurita from Knowmads, Infocology of the future
Scoop.it!

Finland Has Just Launched a World-First Universal Basic Income Experiment

Finland Has Just Launched a World-First Universal Basic Income Experiment | Plant Gene Seeker -PGS | Scoop.it
It looks like 2,000 citizens in Finland will welcome the new year with outstretched arms.

These Finns are the lucky recipients of a guaranteed income beginning this year, as the country’s government finally rolls out its universal basic income (UBI) trial run.

UBI is a potential source of income that could one day be available to all adult citizens, regardless of income, wealth, or employment status.

This pioneering UBI program was launched by the federal social security institution, Kela. It will give out €560 (US$587) a month, tax free, to 2,000 Finns that were randomly selected.

The only requirement was that they had to be already receiving unemployment benefits or an income subsidy.

The program allows unemployed Finns to not lose their benefits, even when they try out odd jobs.

"Incidental earnings do not reduce the basic income, so working and … self-employment are worthwhile no matter what," says Marjukka Turunen, legal unit head at Kela.

If successful, the program could be extended to include all adult Finns.

"Its purpose is to reduce the work involved in applying for subsidies, as well as free up time and resources for other activities, such as making or applying for work," according to a press release by Kela.

Furthermore, the Finnish government, as well as UBI advocates, may see how this program can end up saving more money for Finland in the long run - as it is less costly than maintaining social welfare services for the unemployed.

Via Wildcat2030
more...
prgnewshawaii's curator insight, January 5, 12:48 AM

Interesting concept from Finland. The basic argument says a basic income stipend will allow the unemployed to search for work full-time and will be less costly than subsidizing a country wide welfare program.  

Russ Roberts

Hawaii Intelligence Digest

https://hawaiiintelligencedigest.com

https://paper.li/f-1482109921

Charley Bang's comment, January 5, 8:29 AM
https://goo.gl/bgaq38
Scooped by Andres Zurita
Scoop.it!

Realizing pipe dreams – a detailed picture of vascular development

Realizing pipe dreams – a detailed picture of vascular development | Plant Gene Seeker -PGS | Scoop.it

This special issue of Journal of Experimental Botany focuses on the developmental mechanisms required to generate plant vascular tissue. The focus is Arabidopsis, including the three models for initial patterning involving the interaction of auxin and cytokinin, and going on to look at expansion and differentiation into xylem and phloem. Bryophyte and tree models are also considered, as well as new techniques for analyzing the vasculature of mature plants.

more...
No comment yet.
Rescooped by Andres Zurita from Plants and Microbes
Scoop.it!

Scienmag: Genome sequence reveals why the whitefly is such a formidable threat to food security (2016)

Scienmag: Genome sequence reveals why the whitefly is such a formidable threat to food security (2016) | Plant Gene Seeker -PGS | Scoop.it

ITHACA, NY–Researchers have sequenced the genome of the whitefly (Bemisia tabici), an invasive insect responsible for spreading plant viruses worldwide, causing billions of dollars in crop losses each year.

 

The genome study, led by Associate Professor Zhangjun Fei of the Boyce Thompson Institute (BTI), offers many clues to the insect's remarkable ability to resist pesticides, transmit more than 300 plant viruses, and to feed on at least 1,000 different plant species. Published today in the journal BMC Biology, the study will serve as a foundation for future work to combat this global pest.

"Whitefly is an economically important pest for agriculture crops. It causes direct damage and also is a major vector for viruses, like Tomato yellow leaf curl virus, Cassava mosaic virus and Cassava brown streak virus, so it creates huge crop losses and poses serious threats to food security, especially in Africa and other parts of the developing world," said Fei.

 

In collaboration with a group of international colleagues, BTI researchers created a high-quality draft genome sequence of the whitefly and identified genes that code for proteins. The genome sequence can be accessed at the whitefly genome database developed by the Fei lab.

 

An analysis showed that, compared to related species, the whitefly has expanded families of detoxification genes. It also has extra genes that code for proteins related to virus acquisition and transmission, as well as insecticide resistance.

 

In an impressive example of horizontal gene transfer, the whitefly has acquired 142 genes from bacteria or fungi, including some coding for enzymes that break down foreign chemicals. These genes likely allow the whitefly to feed on diverse types of plants and to rapidly evolve resistance to insecticides.

 

Because pesticides are ineffective at keeping whitefly populations in check, collaborators at USDA plan to use the genome sequence to develop a control strategy using RNA interference (RNAi). Once scientists pinpoint the genes necessary for virus transmission and survival in the whitefly genome, they can develop new varieties of crops that will produce RNA molecules that block the expression of those necessary genes, killing the whitefly or preventing it from spreading the virus .


Via Kamoun Lab @ TSL
more...
No comment yet.
Scooped by Andres Zurita
Scoop.it!

System analysis of metabolism and the transcriptome in Arabidopsis thaliana roots reveals differential co‐regulation upon iron, sulfur and potassium deficiency

System analysis of metabolism and the transcriptome in Arabidopsis thaliana roots reveals differential co‐regulation upon iron, sulfur and potassium deficiency | Plant Gene Seeker -PGS | Scoop.it

Deprivation of mineral nutrients causes significant retardation of plant growth. This retardation is associated with nutrient-specific and general stress-induced transcriptional responses. In this study, we adjusted the external supply of iron, potassium and sulfur to cause the same retardation of shoot growth. Nevertheless, limitation by individual nutrients resulted in specific morphological adaptations and distinct shifts within the root metabolite fingerprint. The metabolic shifts affected key metabolites of primary metabolism and the stress-related phytohormones, jasmonic, salicylic and abscisic acid. These phytohormone signatures contributed to specific nutrient deficiency-induced transcriptional regulation. Limitation by the micronutrient iron caused the strongest regulation and affected 18% of the root transcriptome. Only 130 genes were regulated by all nutrients. Specific co-regulation between the iron and sulfur metabolic routes upon iron or sulfur deficiency was observed. Interestingly, iron deficiency caused regulation of a different set of genes of the sulfur assimilation pathway compared with sulfur deficiency itself, which demonstrates the presence of specific signal-transduction systems for the cross-regulation of the pathways. Combined iron and sulfur starvation experiments demonstrated that a requirement for a specific nutrient can overrule this cross-regulation. The comparative metabolomics and transcriptomics approach used dissected general stress from nutrient-specific regulation in roots of Arabidopsis.

more...
No comment yet.