Search results for " plant"
showing 10 items of 3687 documents
Olive Growing in a Time of Change: From Empiricism to Genomics
2016
Since its beginning, the olive crop has been a long-lived agricultural system in the Mediterranean Basin being well adapted to this area. Traditional olive growing, still prevalent in most producing areas, is characterized by low tree density and rainfed orchards with low yield and manually harvested. The traditional olive growing technology is local, diverse, and empirically based. New high density, irrigated, and mechanically harvested orchards has been progressively planted since the end of World War II. These plantations produce high crops at low costs, but they reduce the diversity of cultivars, increase the demand of inputs and the risk of environment unbalances. The expansion and int…
Highly efficient construction of infectious viroid-derived clones
2019
[Background] Viroid research generally relies on infectious cDNA clones that consist of dimers of the entire viroid sequence. At present, those dimers are generated by self-ligation of monomeric cDNA, a strategy that presents several disadvantages: (i) low efficiency, (ii) it is a non-oriented reaction requiring tedious screenings and (iii) additional steps are required for cloning into a binary vector for agroinfiltration or for in vitro RNA production.
Crop density rather than ruderal plants explains the response of ancient segetal weeds
2018
AbstractThe influence of ruderal species and crop density on ancient segetal weeds was examined. The experiment was carried out on experimental plots with three different sewing densities of winter triticale. Weeding of ruderal taxa was applied on half of the plots to explore the relation between segetal and ruderal weeds. Variation in species composition by environmental variables was analysed by running Redundancy Analysis (RDA) combined with performing forward selection and variation partitioning for “weeding” and “crop density” as explanatory variables. Additionally, the effect of crop density and weeding was tested separately for segetal and ruderal species along the seasons with the u…
Floral scent in a sexually deceptive Ophrys orchid: from headspace collections to solvent extractions
2018
Sexually deceptive orchid flowers use visual, tactile and olfactory cues of female insects in order to attract males of one or a few closely related species as pollinators. Ophrys L. is the most species-rich genus of sexually deceptive orchids in the Mediterranean Basin. Despite Ophrys pollinated by Andrena male bees use alkanes and mainly alkenes with specific double-bond positions as key signals that trigger pseudocopulatory behavior, some volatile organic compounds (VOCs) with low molecular weight were found as long-range attractants non-eliciting copulatory behavior. Since floral scents in Ophrys have been extensively studied by solvent extractions here we aimed to understand which flor…
Potential risk evaluation for unintended entry of genetically modified plant Propagating material in Europe through import of seeds and animal feed –…
2019
Significant attention has been drawn to the adventitious and technically unavoidable presence of genetically modified (GM) organisms in the food and feed imported into the European Union (EU), while the potential presence of GM seeds in material for cultivation is less studied. Here we report a study from an EU member state, Latvia, during years 2017–2018 regarding monitoring for the presence of GM seeds in certified seed and animal feed material. Eighty-two and 28 samples of seeds intended for cultivation were analyzed in 2017 and 2018, respectively. One soybean sample contained MON40-3-2 soybean seeds (0.09 ± 0.01%) and one maize sample contained MON810 maize seeds (0.08 ± 0.01%). In addi…
Gametic and somatic embryogenesis through in vitro anther culture of different Citrus genotypes
2015
Abstract: In vitro tissue culture represents a useful technique for advancing Citrus breeding and propagation. Among in vitro regeneration systems, anther culture is commonly used to produce haploids and doubled haploids for a fast-track producing homozygous lines, in comparison with the traditional self-pollination approach, which involves several generations of selfing. In addition, anthers culture can produce somatic embryos that can also be used for clonal propagation. In this study, two thermal shocks were applied to the anthers of six Citrus genotypes (two clementine and four sweet oranges), just after they were put in culture. The response obtained was different depending on the geno…
Deregulated High Affinity Copper Transport Alters Iron Homeostasis inArabidopsis
2020
The present work describes the effects on iron homeostasis when copper transport was deregulated in Arabidopsis thaliana by overexpressing high affinity copper transporters COPT1 and COPT3 (COPTOE). A genome-wide analysis conducted on COPT1OE plants, highlighted that iron homeostasis gene expression was affected under both copper deficiency and excess. Among the altered genes were those encoding the iron uptake machinery and their transcriptional regulators. Subsequently, COPTOE seedlings contained less iron and were more sensitive than controls to iron deficiency. The deregulation of copper (I) uptake hindered the transcriptional activation of the subgroup Ib of basic helix-loop-helix (bHL…
The transcriptomics of an experimentally evolved plant-virus interaction
2015
[EN] Models of plant-virus interaction assume that the ability of a virus to infect a host genotype depends on the matching between virulence and resistance genes. Recently, we evolved tobacco etch potyvirus (TEV) lineages on different ecotypes of Arabidopsis thaliana, and found that some ecotypes selected for specialist viruses whereas others selected for generalists. Here we sought to evaluate the transcriptomic basis of such relationships. We have characterized the transcriptomic responses of five ecotypes infected with the ancestral and evolved viruses. Genes and functional categories differentially expressed by plants infected with local TEV isolates were identified, showing heterogene…
PGDH family genes differentially affect Arabidopsis tolerance to salt stress
2019
The first step in the Phosphorylated Pathway of serine (Ser) Biosynthesis (PPSB) is catalyzed by the enzyme Phosphoglycerate Dehydrogenase (PGDH), coded in Arabidopsis thaliana by three genes. Gene expression analysis indicated that PGDH1 and PGDH2 were induced, while PGDH3 was repressed, by salt-stress. Accordingly, PGDH3 overexpressing plants (Oex PGDH3) were more sensitive to salinity than wild type plants (WT), while plants overexpressing PGDH1 (Oex PGDH1) performed better than WT under salinity conditions. Oex PGDH1 lines displayed lower levels of the salt-stress markers proline and raffinose in roots than WT under salt-stress conditions. Besides, the ratio of oxidized glutathione (GSS…
Mycorrhizal symbiosis primes the accumulation of antiherbivore compounds and enhances herbivore mortality in tomato
2021
Abstract Plant association with arbuscular mycorrhizal fungi (AMF) can increase their ability to overcome multiple stresses, but their impact on plant interactions with herbivorous insects is controversial. Here we show higher mortality of the leaf-chewer Spodoptera exigua when fed on tomato plants colonized by the AMF Funneliformis mosseae, evidencing mycorrhiza-induced resistance. In search of the underlying mechanisms, an untargeted metabolomic analysis through ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS) was performed. The results showed that mycorrhizal symbiosis had a very limited impact on the leaf metabolome in the absence of stress, but significantly m…