Search results for "stoma"
showing 10 items of 4137 documents
An integrated proteomic and metabolomic study to evaluate the effect of nucleus-cytoplasm interaction in a diploid citrus cybrid between sweet orange…
2018
Key message: Our results provide a comprehensive overview how the alloplasmic condition might lead to a significant improvement in citrus plant breeding, developing varieties more adaptable to a wide range of conditions. Abstract: Citrus cybrids resulting from somatic hybridization hold great potential in plant improvement. They represent effective products resulting from the transfer of organelle-encoded traits into cultivated varieties. In these cases, the plant coordinated array of physiological, biochemical, and molecular functions remains the result of integration among different signals, which derive from the compartmentalized genomes of nucleus, plastids and mitochondria. To dissect …
Citrus rootstock breeding: response of four allotetraploid somatic hybrids to Citrus tristeza virus induced infections
2018
Four allotetraploid somatic hybrids of citrus, with potential for rootstock improvement, have been evaluated for their response to Citrus tristeza virus (CTV) infection. CTV is the most important viral pathogen affecting citrus production worldwide. Somatic combinations of ‘Milam’ lemon (Citrus jambhiri Lush.) + Sour orange (C. aurantium L Osb.), Calamondin (C. madurensis Lour.) + ‘Keen’ sour orange (C. aurantium L.), Calamondin + ‘Femminello‘ lemon (C. limon L. Burm. F.) and Cleopatra mandarin (C. reshni Hort. ex Tan.) + ‘Femminello’ lemon, were studied. Plants were grafted with CTV-infected “Valencia” sweet orange budwood. Two different CTV strains collected in Sicily, considered as “mild…
Autotetraploid Emergence via Somatic Embryogenesis in Vitis vinifera Induces Marked Morphological Changes in Shoots, Mature Leaves, and Stomata
2021
Polyploidy plays an important role in plant adaptation to biotic and abiotic stresses. Alterations of the ploidy in grapevine plants regenerated via somatic embryogenesis (SE) may provide a source of genetic variability useful for the improvement of agronomic characteristics of crops. In the grapevine, the SE induction process may cause ploidy changes without alterations in DNA profile. In the present research, tetraploid plants were observed for 9.3% of ‘Frappato’ grapevine somatic embryos regenerated in medium supplemented with the growth regulators β-naphthoxyacetic acid (10 µM) and N6-benzylaminopurine (4.4 µM). Autotetraploid plants regenerated via SE without detectable changes in the …
Infestation of broad bean (Vicia faba) by the green stink bug (Nezara viridula) decreases shoot abscisic acid contents under well-watered and drought…
2017
The response of broad bean (Vicia faba) plants to water stress alone and in combination with green stink bug (Nezara viridula) infestation was investigated through measurement of: (1) leaf gas exchange; (2) plant hormone titres of abscisic acid (ABA) and its metabolites, and of salicylic acid (SA); and (3) hydrogen peroxide (H2O2) content. Furthermore, we evaluated the effects of experimentally water-stressed broad-bean plants on N. viridula performance in terms of adult host–plant preference, and nymph growth and survival. Water stress significantly reduced both photosynthesis (A) and stomatal conductance (gs), while infestation by the green stink bug had no effects on photosynthesis but s…
Modelling nonlinear dynamics of Crassulacean acid metabolism productivity and water use for global predictions
2021
Crassulacean acid metabolism (CAM) crops are important agricultural commodities in water-limited environments across the globe, yet modeling of CAM productivity lacks the sophistication of widely used C3 and C4 crop models, in part due to the complex responses of the CAM cycle to environmental conditions. This work builds on recent advances in CAM modeling to provide a framework for estimating CAM biomass yield and water use efficiency from basic principles. These advances, which integrate the CAM circadian rhythm with established models of carbon fixation, stomatal conductance, and the soil-plant-atmosphere continuum, are coupled to models of light attenuation, plant respiration, and bioma…
Physio-morphological traits and drought stress responses in three wild Mediterranean taxa of Brassicaceae
2019
Crop wild relatives (CWRs) have extremely relevant roles in biodiversity conservation, in investigating phylogeny and improving abiotic stress tolerance of crop plants. We screened the variability in leaf functional traits of three CWRs of kale crops (Brassica oleracea) from Sicily, Italy, grown in pots under well-watered and drought conditions. Our aim was to highlight traits in the different genotypes of endemic Sicilian threatened taxa. We measured several structural/anatomical traits (stomatal size, density and stomatal pore index—SPI, leaf mass per area—LMA) and leaf functional traits (stomatal conductance—gs, leaf water potential—ΨL, leaf temperature (TL), leaf relative water content—…
Contrasting biogeographical patterns in Margarella (Gastropoda: Calliostomatidae: Margarellinae) across the Antarctic Polar Front
2021
International audience; Members of the trochoidean genus Margarella (Calliostomatidae) are broadly distributed across Antarctic and sub-Antarctic ecosystems. Here we used novel mitochondrial and nuclear gene sequences to clarify species boundaries and phylogenetic relationships among seven nominal species distributed on either side of the Antarctic Polar Front (APF). Molecular reconstructions and species-delimitation analyses recognized only four species: M. antarctica (the Antarctic Peninsula), M. achilles (endemic to South Georgia), M. steineni (South Georgia and Crozet Island) and the morphologically variable M. violacea (=M. expansa, M. porcellana and M. pruinosa), with populations in s…
Formally described species woefully underrepresent phylogenetic diversity in the common lichen photobiont genus Trebouxia (Trebouxiophyceae, Chloroph…
2020
Lichens provide valuable systems for studying symbiotic interactions. In lichens, these interactions are frequently described in terms of availability, selectivity and specificity of the mycobionts and photobionts towards one another. The lichen-forming, green algal genus Trebouxia Puymaly is among the most widespread photobiont, associating with a broad range of lichen-forming fungi. To date, 29 species have been described, but studies consistently indicate that the vast majority of species-level lineages still lack formal description, and new, previously unrecognized lineages are frequently reported. To reappraise the diversity and the evolutionary relationships of species-level lineages …
Inhibition of NO Biosynthetic Activities during Rehydration of Ramalina farinacea Lichen Thalli Provokes Increases in Lipid Peroxidation
2019
Lichens are poikilohydrous symbiotic associations between a fungus, photosynthetic partners, and bacteria. They are tolerant to repeated desiccation/rehydration cycles and adapted to anhydrobiosis. Nitric oxide (NO) is a keystone for stress tolerance of lichens
Gastrointestinal parasites of two populations of Arctic foxes (Vulpes lagopus) from north-east Greenland
2017
Parasitological examination of 275 faecal samples from Arctic foxes (Vulpes lagopus) collected at Zackenberg Valley and Karupelv Valley in north-east Greenland from 2006 to 2008 was conducted using sieving and microscopy. Overall, 125 (45.5%) samples contained parasite eggs of Taenia crassiceps, Taenia serialis, Toxascaris leonina, Eucoleus boehmi, Physalopteridae and Ancylostomatidae, and Strongyloides-like larvae. As long-term ecological studies are conducted at both sampling locations, the present findings constitute a baseline data set for further parasitological monitoring.