The divalent cations of several transition metal elements have similar chemical properties and, when present in excess, one metal can interfere with the homeostasis of another. To better understand ...the role of interactions between transition metals in the development of metal toxicity symptoms in plants, the effects of exposure to excess nickel (Ni) on copper (Cu) and iron (Fe) homeostasis in the Ni hyperaccumulator plant Alyssum inflatum were examined. Alyssum inflatum was hypertolerant to Ni, but not to Cu. Exposure to elevated subtoxic Ni concentrations increased Cu sensitivity, associated with enhanced Cu accumulation and enhanced root surface Cu(II)-specific reductase activity. Exposure to elevated Ni concentrations resulted in an inhibition of root-to-shoot translocation of Fe and concentration-dependent progressive Fe accumulation in root pericycle, endodermis and cortex cells of the differentiation zone. Shoot Fe concentrations, chlorophyll concentrations and Fe-dependent antioxidant enzyme activities were decreased in Ni-exposed plants when compared with unexposed controls. Foliar Fe spraying or increased Fe supply to roots ameliorated the chlorosis observed under exposure to high Ni concentrations. These results suggest that Ni interferes with Cu regulation and that the disruption of root-to-shoot Fe translocation is a major cause of nickel toxicity symptoms in A. inflatum.
Feedstocks for industrial applications ranging from polymers to lubricants are largely derived from petroleum, a non-renewable resource. Vegetable oils with fatty acid structures and storage forms ...tailored for specific industrial uses offer renewable and potentially sustainable sources of petrochemical-type functionalities. A wide array of industrial vegetable oils can be generated through biotechnology, but will likely require non-commodity oilseed platforms dedicated to specialty oil production for commercial acceptance. Here we show the feasibility of three Brassicaceae oilseeds crambe, camelina, and carinata, none of which are widely cultivated for food use, as hosts for complex metabolic engineering of wax esters for lubricant applications. Lines producing wax esters >20% of total seed oil were generated for each crop and further improved for high temperature oxidative stability by down-regulation of fatty acid polyunsaturation. Field cultivation of optimized wax ester-producing crambe demonstrated commercial utility of these engineered crops and a path for sustainable production of other industrial oils in dedicated specialty oilseeds.
Background and aims
Crucifers grown as cover crops are known to reduce sulphate leaching (S catch-crop service) and release large amounts of mineral sulphate for the subsequent cash crop once ...incorporated into the soil (S green-manure service). Crucifer-legume cover crop mixtures are effective to obtain high nitrogen related services, but few data exist on their performances for S-related services. Our study aimed to assess performances of a wide variety of bispecific crucifer-legume mixtures designed to provide soil S catch-crop and S green-manure services.
Methods
A two-year field experiment was conducted at two sites near Toulouse, France (silt clay loam soil) and Orléans, France (sandy loam soil) in which cultivars from eight crucifer species and nine legume species were tested as sole and bispecific cover crops.
Results
Crucifer-legume mixtures and crucifer sole cover crops provided the same level of S catch-crop service (12 kg S ha
−1
), significantly higher than that of legume sole cover crops (4 kg S ha
−1
). Similarly, crucifer-legume mixtures provided almost the same level of S green-manure service (5.5 kg S ha
−1
) as crucifer sole cover crops (6.5 kg S ha
−1
).
Conclusion
Our results demonstrate the compatibility and complementarity of certain crucifer and legume species when grown together to provide S and N catch-crop and green-manure services. For a same cover crop species no strong cultivar effect has been highlighted in our growing conditions.
High expression of plant nucleotide binding site leucine-rich repeat (NBS-LRR) defense genes is often lethal to plant cells, a phenotype perhaps associated with fitness costs. Plants implement ...several mechanisms to control the transcript level of NBS-LRR defense genes. As negative transcriptional regulators, diverse miRNAs target NBS-LRRs in eudicots and gymnosperms. To understand the evolutionary benefits of this miRNA-NBS-LRR regulatory system, we investigated the NBS-LRRs of 70 land plants, coupling this analysis with extensive small RNA data. A tight association between the diversity of NBS-LRRs and miRNAs was found. The miRNAs typically target highly duplicated NBS-LRRs In comparison, families of heterogeneous NBS-LRRs were rarely targeted by miRNAs in Poaceae and Brassicaceae genomes. We observed that duplicated NBS-LRRs from different gene families periodically gave birth to new miRNAs. Most of these newly emerged miRNAs target the same conserved, encoded protein motif of NBS-LRRs, consistent with a model of convergent evolution for these miRNAs. By assessing the interactions between miRNAs and NBS-LRRs, we found nucleotide diversity in the wobble position of the codons in the target site drives the diversification of miRNAs. Taken together, we propose a co-evolutionary model of plant NBS-LRRs and miRNAs hypothesizing how plants balance the benefits and costs of NBS-LRR defense genes.
Contemporary climate change is proceeding at an unprecedented rate. The question remains whether populations adapted to historical conditions can persist under rapid environmental change. We tested ...whether climate change will disrupt local adaptation and reduce population growth rates using the perennial plant Boechera stricta (Brassicaceae). In a large‐scale field experiment conducted over five years, we exposed > 106 000 transplants to historical, current, or future climates and quantified fitness components. Low‐elevation populations outperformed local populations under simulated climate change (snow removal) across all five experimental gardens. Local maladaptation also emerged in control treatments, but it was less pronounced than under snow removal. We recovered local adaptation under snow addition treatments, which reflect historical conditions. Our results revealed that low elevation populations risk rapid decline, whereas upslope migration could enable population persistence and expansion at higher elevation locales. Local adaptation to historical conditions could increase vulnerability to climate change, even for geographically widespread species.
Here, we provide direct evidence that climate change has disrupted long‐standing patterns of local adaptation, favoring plants that evolved under hot and dry conditions. Previous empirical studies have suggested that climate change may induce maladaptation, but they have not included direct manipulations of climatic factors to document the extent to which populations were historically locally adapted or the degree to which climate change alters those patterns. Our revised manuscript fills key gaps in the literature by experimentally (1) recovering local adaptation under historical climate conditions, (2) establishing that climate change had already generated maladaptation and will continue to do so, and (3) revealing that upslope and migration could rescue populations demographically.
Glucosinolates (GSL) are naturally occurring β-d-thioglucosides found across the cruciferous vegetables. Core structure formation and side-chain modifications lead to the synthesis of more than 200 ...types of GSLs in Brassicaceae. Isothiocyanates (ITCs) are chemoprotectives produced as the hydrolyzed product of GSLs by enzyme myrosinase. Benzyl isothiocyanate (BITC), phenethyl isothiocyanate (PEITC) and sulforaphane (1-isothioyanato-4-(methyl-sulfinyl) butane, SFN) are potential ITCs with efficient therapeutic properties. Beneficial role of BITC, PEITC and SFN was widely studied against various cancers such as breast, brain, blood, bone, colon, gastric, liver, lung, oral, pancreatic, prostate and so forth. Nuclear factor-erythroid 2-related factor-2 (Nrf2) is a key transcription factor limits the tumor progression. Induction of ARE (antioxidant responsive element) and ROS (reactive oxygen species) mediated pathway by Nrf2 controls the activity of nuclear factor-kappaB (NF-κB). NF-κB has a double edged role in the immune system. NF-κB induced during inflammatory is essential for an acute immune process. Meanwhile, hyper activation of NF-κB transcription factors was witnessed in the tumor cells. Antagonistic activity of BITC, PEITC and SFN against cancer was related with the direct/indirect interaction with Nrf2 and NF-κB protein. All three ITCs able to disrupts Nrf2-Keap1 complex and translocate Nrf2 into the nucleus. BITC have the affinity to inhibit the NF-κB than SFN due to the presence of additional benzyl structure. This review will give the overview on chemo preventive of ITCs against several types of cancer cell lines. We have also discussed the molecular interaction(s) of the antagonistic effect of BITC, PEITC and SFN with Nrf2 and NF-κB to prevent cancer.
To achieve host colonization, successful pathogens need to overcome plant basal defences. For this, (hemi)biotrophic pathogens secrete effectors that interfere with a range of physiological processes ...of the host plant. AvrLm4-7 is one of the cloned effectors from the hemibiotrophic fungus Leptosphaeria maculans 'brassicaceae' infecting mainly oilseed rape (Brassica napus). Although its mode of action is still unknown, AvrLm4-7 is strongly involved in L. maculans virulence. Here, we investigated the effect of AvrLm4-7 on plant defence responses in a susceptible cultivar of B. napus. Using two isogenic L. maculans isolates differing in the presence of a functional AvrLm4-7 allele absence ('a4a7') and presence ('A4A7') of the allele, the plant hormone concentrations, defence-related gene transcription and reactive oxygen species (ROS) accumulation were analysed in infected B. napus cotyledons. Various components of the plant immune system were affected. Infection with the 'A4A7' isolate caused suppression of salicylic acid- and ethylene-dependent signalling, the pathways regulating an effective defence against L. maculans infection. Furthermore, ROS accumulation was decreased in cotyledons infected with the 'A4A7' isolate. Treatment with an antioxidant agent, ascorbic acid, increased the aggressiveness of the 'a4a7' L. maculans isolate, but not that of the 'A4A7' isolate. Together, our results suggest that the increased aggressiveness of the 'A4A7' L. maculans isolate could be caused by defects in ROS-dependent defence and/or linked to suppressed SA and ET signalling. This is the first study to provide insights into the manipulation of B. napus defence responses by an effector of L. maculans.
Warmer and drier climates have shifted phenologies of many species. However, the magnitude and direction of phenological shifts vary widely among taxa, and it is often unclear when shifts are ...adaptive or how they affect long-term viability. Here, we model evolution of flowering phenology based on our long-term research of two species exhibiting opposite shifts in floral phenology: Lythrum salicaria, which is invasive in North America, and the sparse Rocky Mountain native Boechera stricta. Genetic constraints are similar in both species, but differences in the timing of environmental conditions that favour growth lead to opposite phenological shifts under climate change. As temperatures increase, selection is predicted to favour earlier flowering in native B. stricta while reducing population viability, even if populations adapt rapidly to changing environmental conditions. By contrast, warming is predicted to favour delayed flowering in both native and introduced L. salicaria populations while increasing long-term viability. Relaxed selection from natural enemies in invasive L. salicaria is predicted to have little effect on flowering time but a large effect on reproductive fitness. Our approach highlights the importance of understanding ecological and genetic constraints to predict the ecological consequences of evolutionary responses to climate change on contemporary timescales.
This article is part of the themed issue ‘Human influences on evolution, and the ecological and societal consequences’.
•Solar reduction affected the morphometric and biochemical profile of novel foods.•Rocket sprouts and baby-leaves exhibited the highest morphometric values.•Broccoli were significantly positively ...correlated with antioxidant capacity.•These findings useful for selecting genotypes efficient with solar reduction.•Optimizing the crop productivity valorising the reduction of solar radiation.
The solar radiation (SR) is one of the key factors for plant adaptation, and of its growth and development, and for several horticultural crops is important for reaching good yield and produce quality. The SR vary in Europe from 2189 to 517 kwh m−2 from Sicily to North cape. Sprouts, microgreens, and baby-leaves, recognized as novel foods due to their high nutraceutical value, have attracted significant attention in the market. The novel foods production could be affected by solar radiation especially when it is carried out in greenhouse in several countries and along their latitudes. Our study aimed to investigate how solar radiation affects the growth of these plants by conducting a thorough analysis of their morphometric characteristics and biochemical profiles. Two different genotypes of commercial rocket, namely Eruca sativa L. var. darkita and var. lobata, along with the Sicilian Black sprouting broccoli (Brassica oleracea var. italica Plenck, Broccolo nero), were examined at different initial plant growth stages, sprouts, microgreens, and baby-leaves. The experimental trial was carried out in Sicily (Italy) utilizing black shade nets with varying levels of solar radiation (SR100, SR60, SR40). The harvested plantlets were analysed for their main morphometric traits, as sprout weight, hypocotyl length, cotyledon dimensions, in addition to the dimensions of the first true leaf for microgreens, and stem length for baby-leaves. Several biochemical parameters, such as total phenolic content (TPC), total flavonoid content (TFC), and several antioxidant assays including DPPH (2,2-diphenyl-1-picrylhydrazyl), ORAC (oxygen radical absorbance capacity), and FRAP (ferric reducing antioxidant power) were determined. The total glucosinolate content, the sucrose, fructose, fructooligosaccharides (FOS), and total sugars amount were detected. We observed significant variations in the sugar content, particularly under reduced solar radiation and during the baby-leaves stage, characterized by decreased FOS levels and simultaneous increases in sucrose, glucose, and fructose. Moreover, antioxidant capacity showed a progressive enhancement from sprouts to baby-leaves. FRAP and DPPH capacity were significantly affected by the genotype. Interestingly, TFC was the most influenced by SR100, particularly in microgreens. This expanded knowledge base not only advances scientific understanding of these novel foods but also provides substantial adaptation to the different solar radiation conditions in different latitude of the world, permitting to individuate the genotypes more efficient in relation to the solar radiation available.
Plant-parasitic nematodes (PPNs) are an important damaging biotic agent for numerous crops around the world, causing serious losses directly and indirectly. Cultural and chemical control strategies ...were mainly used to PPNs management. However, the choice of chemical nematicides is strictly limited in the agrosystems due to their toxicity, their impact to the environment and, therefore, banning policies. The main lines of action of biological control strategies for nematode control, are based on the development of antagonist microorganism formulations and the use of plant extracts with nematicidal potential. There are many plant secondary metabolites with effective nematicidal potential. In this sense, glucosinolates (GSLs) and, especially, glucosinolate hydrolysis products (GHPs) show relevant nematicidal activity. The effects through which these compounds control nematodes, both direct and indirect are diverse, such as toxicity, anti-hatching effect or promotion of competing saprophytic nematodes or nematophagous bacteria populations. The present work compiles many of the studies that describe the use of GSLs and GHPs as nematicides in agriculture, through very diverse strategies that range from crop rotation with Brassicales to the direct application of GSLs and GHPs to the soil. The authors present GSLs and GHPs as a more sustainable and suitable alternative in nematode control, remarking the need to further research in the modes of action and the impact on environment.
•Plant-parasitic nematodes significantly reduce the productivity of numerous crops.•New safe strategies are required for nematodes control in agrosystem.•Glucosinolates and hydrolysis-derivatives have great nematicidal capacity.•Future research should focus on the nematicidal mechanisms of these compounds.•Side effects on soil microbiota and environment should be further investigated.
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