E3 ligase BRUTUS Is a Negative Regulator for the Cellular Energy Level and the Expression of Energy Metabolism-Related Genes Encoded by Two Organellar Genomes in Leaf Tissues

Among vegetable plants, red beet contains a relatively high level of the B vitamin folic acid. Although many leafy green vegetables contain high levels of folic acid, red beet is consumed primarily as a root vegetable. Folic acid levels have been quantified in various vegetable plants, but little information exists regarding the accumulation and distribution of this vitamin in plant tissues. The objective of this study was to characterize free folic acid content (FFAC) in shoot and root tissue during growth of two red beet inbreds. Experiments were conducted in a greenhouse during 1993, 1994 and 1995. Two inbreds, W384 and W357, were planted in randomized complete blocks and shoot and root tissues were separately harvested at 60, 80, and 100 days after planting (DAP). Significant differences between years, tissue portions, and among harvest dates were detected, however, similar patterns in FFAC accumulation and distribution were observed between inbreds and years. FFAC in shoot tissue was significantly greater than root tissue for both inbreds. Accumulation of FFAC was linear for both inbreds across harvest dates for root tissue but not for shoot tissue. FFAC accumulation in shoot tissue increased sharply from 60 to 80 DAP but decreased sharply from 80 to 100 DAP. These results demonstrate that FFAC accumulates differentially in root and shoot tissue in a red beet plant. Maximum folic acid levels in shoot tissue are achieved prior to those in root tissue.

This study was conducted to investigate the biochemical responses of the shoot and root tissues of sainfoin to drought stress under in vitro conditions. Seeds of sainfoin were cultured on MS (Murashige and Skoog) medium with addition of concentrations of PEG-6000 (50, 100, and 150 g/l). Biochemical analyzes (CAT, SOD, GR, and APX enzyme activity; proline, malondialdehyde (MDA) and chlorophyll contents) were carried out on the 35-day-old seedlings. The principal results of the study were that CAT and SOD antioxidant enzymes seemed to play a critical role in oxidative stress in both tissues of sainfoin seedlings. On the other hand, a significant decrease in GR activity and no change in APX activity detected in both tissues under stress. The contents of proline and MDA increased in both tissues while the chlorophyll contents decreased in the shoot tissue. Antioxidant enzyme activities seemed to be more active in the root tissue than the shoot tissue. Accumulation of proline was higher in the root tissue, while the MDA content was higher in the shoot tissue of the seedlings.

Sitosterol, campesterol, stigmasterol, and cholesterol were isolated from green wheat (Triticium aestivum var. Monon) seedlings. Sitosterol was the predominant sterol extracted from the shoot, root, and crown tissue. Cholesterol accounted for less that 1% of sterol in shoot tissue with only trace amounts in the root. A temperature change from 10 to 1 C resulted in a general decrease in sitosterol, stigmasterol, and campesterol in the shoot tissue. The cholesterol level was not altered significantly by the temperature change. The sterols in the root responded in a manner very different from those in the shoots. With the reduction in temperature, sterols first decreased and then recovered over a period of 7 to 14 days to levels that were equal to or exceeded the original levels. From these experiments, it would appear that root tissue can acclimate to the lower temperatures and continue sterol synthesis at the normal rate. The level and response of sterols in the crown tissue were intermediate between the root and shoot tissue. At 10 C the crown response was similar to that of root tissue, whereas, at 1 C the response more closely resembled that of the shoot.

Salinity-fertility interaction has not been properly explored especially in saline-sodic soils. Therefore, the current study investigated the response of wheat (Triticum aestivum L.) to saline irrigation water in saline-sodic soil supplemented with potassium (K) and phosphorus (P). Wheat was grown in pots filled with saline-sodic soil which were irrigated either with normal or saline water. Potassium and P fertilizers were applied at two levels. Results indicated that growth of wheat plants was impaired by saline irrigation resulting in a decreased grain and dry matter yield. The P application had significant effect on the dry matter yield and other yield components. Potassium application significantly increased dry matter yield and root mass. Wheat yield increased by 14 and 7% with the application of 150 kg K2O ha-1 and 120 kg P2O5 ha-1 over the control soil under saline irrigation. The higher yield was obtained with combined P and K treatment under non-saline irrigation. The P addition significantly affected shoot and root [P] and [Na], [K] and [Mg] in the shoot tissue while the K:Na ratio produced non-significant effects under both irrigation waters. The addition of K significantly affected [Na], [K] and K:Na ratio in shoot. All other root parameters were significantly affected by the K addition. The Ca uptake by roots increased with saline irrigation. The P addition increased [P] in plant tissue. The Na uptake by root and shoot tissues was depressed with the addition of P and K fertilizers. The higher K uptake increased K:Na ratio in both shoot and root tissues. The values of EC, SAR and [P], [Na], [Ca], [Mg], [Cl] and ratios of Na:K, Ca:P, Cl:P and SO4:P in the soil leachates significantly increased with saline irrigation. The P addition had significant bearing on the soil pH, SAR, [P], [SO4], [CO3] and [HCO3] and Ca:P, Cl:P and SO4:P ratios in leachates. Saline irrigation significantly increased ECe, [Na], [K], [Ca], [Mg], [Cl], [CO3], SAR and ratios of Ca:P, Cl:P and SO4:Cl in saturated extracts of post-harvest soils. This study could suggest that the addition of P and K under saline-sodic conditions may affect salts and nutrients dynamics of the soil and was useful for crop productivity.

ABSTRACTBoron (B) is an essential micronutrient for plants through paticipating key reactions such as reproduction, development, and regeneration. Similar to its deficiency, its over-concentations possess toxic effects on plant growth. In this work, possible boron toxicity was researched through evaluating alaterations in antioxidant enzymes, oxidative stress biomarkers, and chlorophyll contents for two types of lentil species as red (native) and green (winter flake 11) lentil (Lens culinaris L.cv) cultivars, which are indigenous to Turkey. Ten days old seedling lentil plants were subjected to low as 0.5, 1.0 mM and high 2.0 and 5.0 mM boric acid treatments for 7 days. B worked as a growth-promoting nutrient for 0.5, 1.0, and 2.0 mM concentration by enhancing length and weight of both shoot and root tissues, while it started showed its suppression effect on these tissues at 5-mM cocentration, which were obtained more dramatic for green lentil in comparison to red lentil. In contrast to this, oxidative stress markers such as MDA, H2O2, and proline concentrations showed increasing trend for 0.5, 1.0, 2.0, and 5.0 mM B treatment, accompanied with a change in photosynthetic pigment concentrations (p < 0.01). MDA in red lentil shoot control was 30,3871 (μmol/gFW) and it was significantly increased to 36,5806 and 51,7414 by the 2.0 and 5.0 B rates, respectively. However, enzymes in anti-oxidation metabolism include superoxide dismutase (SOD), guaiacol peroxidase (GPX), lipoxygenase (LOX), glutathione peroxidase (GSH-Px) activities were obtained higher in high-B-treated groups, while decreased and stable activities were obtained for catalase (CAT) and ascorbate peroxidase (APX) enzymes. CAT and APX activities were higher than those were obtained for 2.0 and 5.0 mM B treatments in both root and shoot tissues. The lentil species manipulated their metabolism to suppress B-stress, and enhanced growth in shoot and root tissues up to 5-mM B stress even though oxidative stress markers showed increasing trend from low B concentrations, 1.0 mM. Therefore, B stress can be claimed as “doubled edge sword” for these lentil species.AbbreviationsAOS, active oxygen species; APX, ascorbate peroxidase; CAT, catalase; DAB, diamino-benzidine tetrahydrochloride; DMSO, dimethyl sulfoxide DW, dry weight; EDTA, ethylenediamine-N,N,N0,N0-tetraacetic acid; FW, fresh weight GPX, guaiacol peroxidase; GSH-Px, glutathione peroxidase; LOX, lipoxygenase; MDA, malondialdehyde; NBT, nitroblue tetrazolium; PEG, polyethylene glycol; ROS, reactive oxygen species; SOD, superoxide dismutase; H2O2, Hydrogen peroxide;

Simultaneous exposure of wheat (Triticum aestivum L.) to CuO and S nanoparticles alleviates toxicity by reducing Cu accumulation and modulating antioxidant response

The freezing tolerance of many plants, such as pea (Pisum sativum), is increased by exposure to low temperature or abscisic acid treatment, although the physiological basis of this phenomenon is poorly understood. The freezing tolerance of pea shoot tips, root tips, and epicotyl tissue was tested after cold acclimation at 2°C, dehydration/rehydration, applications of 10 -4 M abscisic acid (ABA), and deacclimation at 25°C. Tests were conducted using the cultivar 'Alaska', an ABA-deficient mutant 'wil', and its 'wild-type'. Freezing injury was determined graphically as the temperature that caused 50% injury (T 50 ) from electrical conductivity. Endogenous ABA was measured using an indirect enzyme-linked immunosorbant assay, and novel proteins were detected using 2-dimensional polyacrylamide gel electrophoresis. The maximum decrease in T 50 for root tissue was 1°C for all genotypes, regardless of treatment. For 'Alaska' shoot tips and epicotyl tissue, exogenous ABA increased the freezing tolerance by -1.5 to -4.0°C, while cold treatment increased the freezing tolerance by -7.5 to -14.8°C. Cold treatment increased the freezing tolerance of shoot tips by -9 and -15°C for 'wil' and 'wild-type', respectively. Cold acclimation increased endogenous ABA concentrations in 'Alaska' shoot tips and epicotyls 3- to 4-fold. Immunogold labeling increased noticeably in the nucleus and cytoplasm of the epicotyl after 7 d at 2°C and was greatest after 30 d at the time of maximum freezing tolerance and soluble ABA concentration. Cold treatment induced the production of seven, three, and two proteins in shoot, epicotyl, and root tissue of 'Alaska', respectively. In 'Alaska' shoot tissue, five out of seven novel proteins accumulated in response to both ABA and cold treatment. However, only a 24 kDa protein was produced in 'wit' and 'wild-type' shoot and epicotyl tissues after cold treatment. Abscisic acid and cold treatment additively increased the freezing tolerance of pea epicotyl and shoot tissues through apparently independent mechanisms that both resulted in the production of a 24 kDa protein.

Abiotic stresses such as salinity influence agricultural production. Plants generally respond to stimulus conditions in a complex manner involving many genes and proteins. In the evolution process, halophyte plant Aeluropus littoralis has been proven to have abiotic stress-tolerance capacity. A. littoralis is a salt-resistant halophyte providing a wealthy genetic resource for developing salinity tolerance in crop plants. In the present study, the expression of four candidate ESTs including PKL, 5PTase, NUC-L2 and GLYI genes were analyzed in root and shoot tissues by quantitative Real-Time PCR in multiple time points under 600 mM NaCl stress and recovery conditions . Al5PTase gene showed the highest significant up-regulation in shoot and root tissues. However, a significant down-regulation was found for AlGLY gene in root tissues. Furthermore, we found the unique up-regulations for AlPKL and AlNUC-L2 genes expression magnitudes in root tissues under recovery conditions. These results may provide useful information for further understanding of the role of A. littoralis genes and their regulatory pathways, revealing important genetic resources for crop improvement.

Water quality and quantity are critical issues in the Southwest United States and many other locations in the world. Use of reclaimed water for landscape irrigation can conserve potable water significantly and possibly reduce fertilizer application. A potential concern of using alternative water sources is elevated salt levels, which can have adverse effects on plant growth and aesthetic appearance. Most Texas native wildflowers are known to be hardy and easy to maintain, and are drought tolerant after establishment. In addition, native wildflowers provide wildlife habitat and support native pollinators. However, little information is available on salinity tolerance of many Texas native wildflower species. In this study, two separate hydroponic experiments were conducted to determine salt tolerance of three Texas native wildflower species: Gaura villosa Torr. (wooly gaura), Xanthisma texanum DC. (Texas sleepy daisy), and Ipomopsis rubra (L.) Wherry (standing cypress). Species were suspended in a hydroponic setting using a randomized complete block design with a control [municipal reverse-osmosis (RO) water with a nutrition solution at an electrical conductivity (EC) of 3.0 dS·m –1 ] and three salinity treatments: 5.0, 7.0, and 11.0 dS·m –1 EC. Sixty days after salinity treatments were initiated, percent survival, visual rating, fresh weight, and length measurements were recorded on root and shoot tissue. To determine tissue percentage sodium (Na + ), calcium (Ca 2+ ), and chloride (Cl – ), shoot and root tissues were dried and ground for tissue analysis. At the end of each experiment, total percent survival for X. texanum, G. villosa , and I. rubra were 100%, 94%, and 76%, respectively, with the greatest mortality rate at the highest salinity treatment. Shoot dry weight and plant growth index (PGI) decreased in all three species as salinity of irrigation water increased. Visual qualities of all species were mainly compromised at the highest salinity level. Ion concentrations in root and shoot tissues were affected by salinity levels and varied among species. Different mechanisms of salt tolerance (ion exclusion, salt excretion, and tissue tolerance to high concentrations of Na + or Cl – ) have been observed among wildflower species, and results indicate different salt tolerance mechanisms were exhibited by each trial species. In addition, results indicate I. rubra can be identified as moderately salt tolerant (EC up to 7.0 dS·m –1 ), whereas, X. texanum and G. villosa can be classified as salt tolerant (EC up to 11.0 dS·m –1 ). Results from this study suggest great potential of these native Texas wildflowers in landscapes using limited-quality irrigation water or landscapes with soil salinity concerns.

Background: Shoots and roots are autotrophic and heterotrophic organs of plants with different physiological and biochemical functions under stress conditions. The metabolites involved in tolerance enhancement differed between roots and shoots. In this study, the biochemical changes occurring in shoot and root organs under salt stress and the level of these changes were investigated. However, these changes in shoot and root organs were compared. Methods: Seeds of common vetch were sown and subjected to 14 days of salt stress in basal MS medium containing 100 mM NaCl. In shoot and root tissue, biochemical parameters such as antioxidant enzymes activities (GR, APX, SOD and CAT), malondialdehyde (MDA) content and proline accumulation were determined. Result: Results of the study indicated that the activities of antioxidant enzymes (SOD, CAT (except in shoot), GR and APX), MDA and proline accumulation enhanced by salt stress in both organs. On the other hand, morphological parameters decreased in both tissues. It seemed that antioxidant enzyme activities more active in root tissues. However, proline accumulation was found higher in shoot tissues than root tissue, while MDA content was higher in root tissue than shoot tissue. The present investigation provides essential information for the antioxidant components of the shoot and root organs of vetch seedlings under salt stress.

Soybean shoot metabolism of isopropyl-3-chlorocarbanilate: Ortho and para aryl hydroxylation

Brassica species are increasingly being used as cover crops to suppress soil-borne diseases in potato cropping systems. Experiments were conducted in controlled environments and in the field to evaluate the effects of cover crop root or shoot or a combination of root and shoot tissues on potato root and tuber health. In a lab assay we examined the extent to which volatile compounds released from tissues of two cover crop species, rye (Cereale secale L.) and oriental mustard (Brassica juncea L.), could inhibit mycelium growth of two important potato diseases, Rhizoctonia solani and Pythium ultimum. Twenty-four hours into the lab assay, volatile compounds from all residues suppressed fungal growth. After 48 h, marked suppression of hyphal growth continued in the presence of mustard residues but not in the presence of rye tissues or the control without tissues. A 75 L volume container experiment evaluated the effect of incorporating different quantities of mustard shoot and root tissues (none, comparable to field level and fourfold field level) into R. solani and P. ultimum infested soil on potato growth, root health and tuber disease. In the container study, incorporating mustard shoots at the highest dose increased potato yield by 54% and reduced disease rating to 2.3 compared to a severe rating of 4.4 in the control. In the field trial, potato growth, root health and tuber disease levels were evaluated in plots where disease management involved either incorporation of mustard or rye cover crop roots, shoots and whole plants (roots plus shoots) or standard farmer practice of a fumigated fallow as a control. White root tissue was used as a health indicator, and averaged 58 and 78% in the fumigated control and mustard cover crop treatments, respectively. The highest healthy root tissue status (91%) was recorded where whole plants of mustard were incorporated. In contrast to the visual assessment of root and tuber health, tuber yield in the field was not influenced by cover crop treatment. Across experiments, the incorporation of or exposure to whole mustard plants was consistently effective at suppressing soil-borne fungi and promoting healthy roots and tubers, especially at higher rates of biomass. Mustard should be managed so as to maximize incorporated biomass for effective biofumigation. Multipurpose management requiring removal of mustard shoots is incompatible with promoting potato rhizosphere health.

BackgroundBacopa monnieri commonly known as Brahmi is utilized in Ayurveda to improve memory and many other human health benefits. Bacosides enriched standardized extract of Bacopa monnieri is being marketed as a memory enhancing agent. In spite of its well known pharmacological properties it is not much studied in terms of transcripts involved in biosynthetic pathway and its regulation that controls the secondary metabolic pathway in this plant. The aim of this study was to identify the potential transcripts and provide a framework of identified transcripts involved in bacosides production through transcriptome assembly.ResultsWe performed comparative transcriptome analysis of shoot and root tissue of Bacopa monnieri in two independent biological replicate and obtained 22.48 million and 22.0 million high quality processed reads in shoot and root respectively. After de novo assembly and quantitative assessment total 26,412 genes got annotated in root and 18,500 genes annotated in shoot sample. Quality of raw reads was determined by using SeqQC-V2.2. Assembled sequences were annotated using BLASTX against public database such as NR or UniProt. Searching against the KEGG pathway database indicated that 37,918 unigenes from root and 35,130 unigenes from shoot were mapped to 133 KEGG pathways. Based on the DGE data we found that most of the transcript related to CYP450s and UDP-glucosyltransferases were specifically upregulated in shoot tissue as compared to root tissue. Finally, we have selected 43 transcripts related to secondary metabolism including transcription factor families which are differentially expressed in shoot and root tissues were validated by qRT-PCR and their expression level were monitored after MeJA treatment and wounding for 1, 3 and 5 h.ConclusionsThis study not only represents the first de novo transcriptome analysis of Bacopa monnieri but also provides information about the identification, expression and differential tissues specific distribution of transcripts related to triterpenoid sapogenin which is one of the most important pharmacologically active secondary metabolite present in Bacopa monnieri. The identified transcripts in this study will establish a foundation for future studies related to carrying out the metabolic engineering for increasing the bacosides biosynthesis and its regulation for human health benefits.

The relationship between shoot growth and [(3)H]gibberellin A20 (GA20) metabolism was investigated in the GA-deficient genotype of peas, na Le. [17-(13)C, (3)H2]gibberellin A20 was applied to the shoot apex and its metabolic fate examined by gas chromatographic-mass spectrometric analysis of extracts of the shoot and root tissues. As reported before, [(13)C, (3)H2]GA1, [(13)C, (3)H2]GA8 and [(13)C, (3)H2]GA29 constituted the major metabolites of [(13)C, (3)H2]GA20 present in the shoot. None of these GAs showed any dilution by endogenous (12)C-material. [(13)C, (3)H2]GA29-catabolite was also a prominent metabolite in the shoot tissue but showed pronounced isotope dilution probably due to carry-over of endogenous [(12)C]GA29-catabolite from the mature seed. In marked contrast to the shoot tissue, the two major metabolites present in the roots were identified as [(13)C, (3)H2]GA8-catabolite and [(13)C, (3)H2]GA29-catabolite. Both of these compounds showed strong dilution by endogenous (12)C-material. Only low levels of [(13)C, (3)H2]GA1, [(13)C, (3)H2]GA8, [(13)C, (3)H2]GA20 and [(13)C, (3)H2]GA29 accumulated in the roots. It is suggested that compartmentation of GA-catabolism may occur in the root tissue in an analogous manner to that shown in the testa of developing seeds. Changes in the levels of [1β,3α-(3)H2]GA20 metabolites over 10 d following application of the substrate to the shoot apex of genotype na Le confirmed the accumulation of [(3)H]GA-catabolites in the root tissues. No evidence was obtained for catabolic loss of [(3)H]GA20 by complete oxidation or conversion to a methanol-inextractable form. The results indicate that the root system may play an important role in the regulation of biologically active GA levels in the developing shoot of Na genotypes of peas.

Whilst plastids are fundamental to many aspects of plant biology and the production of enhanced crop cultivars, research into the dynamics of non-green plastids has remained somewhat disregarded by the scientific community compared to chloroplasts. They are equally pivotal to normal plant development however, and are now increasingly becoming the focus of research made possible by genetic manipulation and reporter gene constructs. &#13;\n&#13;\nThe total plastid content of all plant cells originates from small, undifferentiated plastids termed proplastids found within the meristematic regions of both root and shoot tissue. The cellular regulatory mechanisms controlling the development of plastids in young tissues are poorly understood, especially in the case of non-green plastids in roots. This investigation consequently aimed to elucidate the differences in plastid content, morphology and subcellular localization within epidermal cells derived from the root and shoot apical meristems (RAM and SAM respectively) of Arabidopsis thaliana. &#13;\n&#13;\nQuantification of non-green plastids was facilitated via the use of confocal laser scanning microscopy in conjunction with the expression of plastid-targeted green fluorescent protein driven by a constitutive promoter. Characterization of early seedling development and tissue diversification was also achieved by assessing epidermal cell size relative to developmental progression, ultimately facilitating comparative analyses of plastid dynamics on both a temporal and tissue-varietal basis.&#13;\n&#13;\nThe number of plastids in epidermal cells within RAM-derived tissue was shown to increase across regions of cell division before being regulated throughout subsequent zones of elongation and maturing root tissue. In contrast, epidermal cells of the hypocotyl exhibit a more generalized increase in plastid number and less strict maintenance of cell plan area coverage during tissue expansion. &#13;\n&#13;\nThe findings presented here suggest the functioning of distinct mechanisms regulating plastid division and growth in relation to cell size within shoot and root apical meristem-derived tissues.