Effects of Coverlys TF150® on the Photosynthetic Characteristics of Grape.

Grape rain-shelter cultivation is a widely employed practice in China. At present, the most commonly used rain shelter film materials are polyvinyl chloride (PVC), polyethylene (PE), ethylene-vinyl acetate copolymer (EVA), and polyolefin (PO). Coverlys TF150® is a woven fabric with an internal antifoggy PE coating that has not yet been popularized as a rain shelter film for grapes in China. To investigate the effects of Coverlys TF150® on grapes, we measured the microdomain environment, leaf development, and photosynthetic characteristics of 'Miguang' (Vitis vinifera × V. labrusca) under rain-shelter cultivation and performed transcriptome analysis. The results showed that Coverlys TF150® significantly reduced (p < 0.05) the light intensity, temperature, and humidity compared with PO film, increased the chlorophyll content and leaf thickness (particularly palisade tissue thickness), and increased stomatal density and stomatal opening from 10:00 to 14:00. Coverlys TF150® was observed to improve the maximum efficiency of photosystem II (Fv/Fm), photochemical quenching (qP), the electron transfer rate (ETR), and the actual photochemical efficiency (ΦPSII) from 10:00 to 14:00. Moreover, the net photosynthetic rate (Pn), intercellular CO2 concentration (Ci), stomatal conductance (Gs), and transpiration rate (Tr) of grape leaves significantly increased (p < 0.05) from 10:00 to 14:00. RNA-Seq analysis of the grape leaves at 8:00, 10:00, and 12:00 revealed 1388, 1562, and 1436 differential genes at these points in time, respectively. KEGG enrichment analysis showed the occurrence of protein processing in the endoplasmic reticulum. Plant hormone signal transduction and plant-pathogen interaction were identified as the metabolic pathways with the highest differential gene expression enrichment. The psbA encoding D1 protein was significantly up-regulated in both CO10vsPO10 and CO12vsPO12, while the sHSPs family genes were significantly down-regulated in all time periods, and thus may play an important role in the maintenance of the photosystem II (PSII) activity in grape leaves under Coverlys TF150®. Compared with PO film, the PSI-related gene psaB was up-regulated, indicating the ability of Coverlys TF150® to better maintain PSI activity. Compared with PO film, the abolic acid receptacle-associated gene PYL1 was down-regulated at all time periods under the Coverlys TF150® treatment, while PP2C47 was significantly up-regulated in CO10vsPO10 and CO12vsPO12, inducing stomatal closure. The results reveal that Coverlys TF150® alleviates the stress of high temperature and strong light compared with PO film, improves the photosynthetic capacity of grape leaves, and reduces the midday depression of photosynthesis.

Vv-circSIZ1 mediated by pre-mRNA processing machinery contributes to salt tolerance.

CircRNAs exist widely in plants, but the regulatory mechanisms for the biogenesis and function of plant circRNAs remain largely unknown. Using extensive mutagenesis of expression plasmids and genetic transformation methods, we analyzed the biogenesis and anti-salt functions of a new grape circRNA Vv-circSIZ1. We identified Vv-circSIZ1 that is mainly expressed in the cytoplasm of xylem. CircSIZ1 is species-specific, and genomic circSIZ1-forming region of seven tested species could be backspliced in Nicotiana benthamiana, but not in Arabidopsis. The retention length of Vv-circSIZ1 flanking introns was significantly positively correlated with its generation efficiency. The precise splicing of Vv-circSIZ1 does not depend on its mature exon sequence or internal intron sequences, but on the AG/GT splicing signal sites and branch site of the flanking introns. The spliceosome activity was inversely proportional to the expression level of Vv-circSIZ1. Furthermore, RNA-binding proteins can regulate the expression of Vv-circSIZ1. The overexpression of Vv-circSIZ1 improved salt tolerance of grape and N. benthamiana. Additionally, Vv-circSIZ1 could relieve the repressive effect of VvmiR3631 on its target VvVHAc1. Vv-circSIZ1 also promoted transcription of its parental gene. Overall, these results broaden our understanding of circRNAs in plants.

VvPL15 Is the Core Member of the Pectate Lyase Gene Family Involved in Grape Berries Ripening and Softening.

The process of ripening and softening in grape begins at veraison and is closely related to the depolymerization of pectin components. A variety of enzymes are involved in pectin metabolism and one class of enzyme, pectin lyases (PLs), have been reported to play an important role in softening in many fruits; however, little information is available on the VvPL gene family in grape. In this study, 16 VvPL genes were identified in the grape genome using bioinformatics methods. Among them, VvPL5, VvPL9, and VvPL15 had the highest expression levels during grape ripening, which suggests that these genes are involved in grape ripening and softening. Furthermore, overexpression of VvPL15 affects the contents of water-soluble pectin (WSP) and acid-soluble pectin (ASP) in the leaves of Arabidopsis and significantly changes the growth of Arabidopsis plants. The relationship between VvPL15 and pectin content was further determined by antisense expression of VvPL15. In addition, we also studied the effect of VvPL15 on fruit in transgenic tomato plants, which showed that VvPL15 accelerated fruit ripening and softening. Our results indicate that VvPL15 plays an important role in grape berry softening during ripening by depolymerizing pectin.

Integrated mRNA and miRNA transcriptome analysis of grape in responses to salt stress.

Salt stress is an important factor which may negatively affect plant growth and development. High concentrations of Na+ ions can destroy the ion balance in plant somatic cells, as well as destroying cell membranes and forming a large number of reactive oxygen species (ROS) and other damage mechanisms. However, plants have evolved numerous defense mechanisms in response to the damages caused by salt stress conditions. Grape (Vitis vinifera L.), a type of economic crop, is widely planted throughout the world. It has been found that salt stress is an important factor affecting the quality and growth of grape crops. In this study, a high-throughput sequencing method was used to identify the differentially expressed miRNAs and mRNAs in grapes as responses to salt stress. A total of 7,856 differentially expressed genes under the salt stress conditions were successfully identified, of which 3,504 genes were observed to have up-regulated expressions and 4,352 genes had down-regulated expressions. In addition, this study also identified 3,027 miRNAs from the sequencing data using bowtie and mireap software. Among those, 174 were found to be highly conserved, and the remaining miRNAs were less conserved. In order to analyze the expression levels of those miRNAs under salt stress conditions, a TPM algorithm and DESeq software were utilized to screen the differentially expressed miRNAs among different treatments. Subsequently, a total of thirty-nine differentially expressed miRNAs were identified, of which fourteen were observed to be up-regulated miRNAs and twenty-five were down-regulated under the salt stress conditions. A regulatory network was built in order to examine the responses of grape plants to salt stress, with the goal of laying a solid foundation for revealing the molecular mechanism of grape in responses to salt stress.

The VvWRKY37 Regulates Bud Break in Grape Vine Through ABA-Mediated Signaling Pathways.

Dormancy is a common survival strategy in plants to temporarily suspend visible growth under unsuitable conditions. The elaborate mechanism underlying bud break in perennial woody plants is gradually illustrated. Here, we identified a grape vine WRKY transcription factor, VvWRKY37, which was highly expressed in dormant buds. It was particularly induced by the application of exogenous abscisic acid, and depressed on exposure to gibberellin and low temperature (4°C) stress at the transcript level. The yeast one-hybrid assay confirmed that VvWRKY37 had a transcriptional activity. Ectopic over-expression of VvWRKY37 significantly delayed bud break of transgenic poplar plants. As an ABA-inducible gene, VvWRKY37 also depressed the expression of ABA catabolic gene CYP707As and enhanced the accumulation of endogenous ABA in transgenic poplar plants. The molecular pieces of evidence showed that VvWRKY37 preferentially recognized and bound W-box 5'-G/CATTGACT/C/G-3' cis-element in vitro. Additionally, VvABI5 and VvABF2 acted as the upstream transcriptional activators of VvWRKY37 via protein-DNA interactions. Taken together, our findings provided valuable insights into a new regulatory mechanism of WRKY TF by which it modulates bud break through ABA-mediated signaling pathways.

The apple BTB protein MdBT2 positively regulates MdCOP1 abundance to repress anthocyanin biosynthesis.

The ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1) plays a central role in light-induced anthocyanin biosynthesis. However, the upstream regulatory factors of COP1 remain poorly understood, particularly in horticultural plants. Here, we identified an MdCOP1-interacting protein, BROAD-COMPLEX, TRAMTRACK AND BRIC A BRAC2 (MdBT2), in apple (Malus domestica). MdBT2 is a BTB protein that directly interacts with and stabilizes MdCOP1 by inhibiting self-ubiquitination. Fluorescence observation and cell fractionation assays showed that MdBT2 increased the abundance of MdCOP1 in the nucleus. Moreover, a series of phenotypic analyses indicated that MdBT2 promoted MdCOP1-mediated ubiquitination and degradation of the MdMYB1 transcription factor, inhibiting the expression of anthocyanin biosynthesis genes and anthocyanin accumulation. Overall, our findings reveal a molecular mechanism by which MdBT2 positively regulates MdCOP1, providing insight into MdCOP1-mediated anthocyanin biosynthesis.

Advances in the regulation of plant salt-stress tolerance by miRNA.

Salt stress significantly affects the growth, development, yield, and quality of plants. MicroRNAs (miRNAs) are involved in various stress responses via target gene regulation. Their role in regulating salt stress has also received significant attention from researchers. Various transcription factor families are the common target genes of plant miRNAs. Thus, regulating the expression of miRNAs is a novel method for developing salt-tolerant crops. This review summarizes plant miRNAs that mediate salt tolerance, specifically miRNAs that have been utilized in genetic engineering to modify plant salinity tolerance. The molecular mechanism by which miRNAs mediate salt stress tolerance merits elucidation, and this knowledge will promote the development of miRNA-mediated salt-tolerant crops and provide new strategies against increasingly severe soil salinization.

Phosphoproteomic analysis of ozone stress-responsive mechanisms in grapevine identifies KEG required for stress regulation.

The environmental damage caused by ozone is of increasing concern globally. The phosphoproteomics approach was used to explore the mechanisms underlying grapevine tolerance to ozone stress and identify phosphoproteins altered by ozone treatment. Results revealed that 194 of 2275 quantitatively analyzed phosphoproteins were significantly regulated after ozone treatment. Biological pathways related to transport were significantly enriched by the differentially regulated phosphoproteins. Among these phosphoproteins, the phosphorylation of RING E3 ligase in grape (V. vinifera KEEP ON GOING, VvKEG) decreased after ozone treatment. Over-expression of VvKEG in Arabidopsis decreased abscisic acid (ABA) sensitivity and enhanced ozone tolerance. Furthermore, VvKEG interacted with the ABA-responsive transcription factor ABSCISIC ACID-INSENSITIVE3 (ABI3). The exogenous application of ABA on grapevine leaves significantly influenced chlorophyll fluorescence, chlorophyll, and malondialdehyde (MDA) contents under ozone treatment; however, treatment with 150 µmol ABA aggravated ozone stress. These results indicate that phosphorylation modification provides information on ozone-induced processes and that VvKEG plays a critical role in these processes via regulation of the ABA signaling pathway in grape.

Melatonin Relieves Ozone Stress in Grape Leaves by Inhibiting Ethylene Biosynthesis.

Ozone (O3) stress severely affects the normal growth of grape (Vitis vinifera L.) leaves. Melatonin (MT) plays a significant role in plant response to various abiotic stresses, but its role in O3 stress and related mechanisms are poorly understood. In order to understand the mechanism of MT in alleviate O3 stress in grape leaves, we perform a transcriptome analyses of grapes leaves under O3 stress with or without MT treatment. Transcriptome analysis showed that the processes of ethylene biosynthesis and signaling were clearly changed in "Cabernet Sauvignon" grapes under O3 and MT treatment. O3 stress induced the expression of genes related to ethylene biosynthesis and signal transduction, while MT treatment significantly inhibited the ethylene response mediated by O3 stress. Further experiments showed that both MT and aminoethoxyvinylglycine (AVG, an inhibitor of ethylene biosynthesis) enhanced the photosynthetic and antioxidant capacities of grape leaves under O3 stress, while ethephon inhibited those capacities. The combined treatment effect of MT and ethylene inhibitor was similar to that of MT alone. Exogenous MT reduced ethylene production in grape leaves under O3 stress, while ethephon and ethylene inhibitors had little effect on the MT content of grape leaves after O3 stress. However, overexpression of VvACO2 (1-aminocyclopropane-1-carboxylate oxidase2) in grape leaves endogenously induced ethylene accumulation and aggravated O3 stress. Overexpression of the MT synthesis gene VvASMT1 (acetylserotonin methyltransferase1) in tobacco (Nicotiana tabacum L.) alleviated O3 stress and reduced ethylene biosynthesis after O3 stress. In summary, MT can alleviate O3 stress in grape leaves by inhibiting ethylene biosynthesis.

Increasing the activity of the Cu/CuAl2O4/Al2O3 catalyst for the RWGS through preserving the Cu2+ ions.

Cu-Al spinel oxide is a highly active catalyst for CO2 conversion to CO. However, it suffers from low surface area. By depositing a silica layer, we protected the catalyst surface and preserved the Cu2+ ions during the calcination process. These ions form well-dispersed Cu sites which participate in the reaction.

Functional characterization of WRKY46 in grape and its putative role in the interaction between grape and phylloxera (Daktulosphaira vitifoliae).

WRKY transcription factors are involved in defense responses caused by biotic stresses. Phylloxera (Daktulosphaira vitifoliae Fitch), a pest widespread in viticulture, elicits transcriptional reprogramming of plant defense-associated components, such as regulons related to WRKYs and salicylic acid (SA) signaling. In this study, we characterized WRKY46, a WRKY transcription factor responsible for phylloxera attack, and revealed the molecular mechanism for WRKY-mediated defense responses to phylloxera. qRT-PCR and GUS staining analyses revealed that WRKY46 is induced in response to phylloxera damage and mechanical wounding. VvWRKY46 is a nuclear-localized transcription factor that activates its downstream target VvCHIB by direct protein-DNA interaction. Regulons involved in the SA-mediated defense response were regulated during incompatible interactions between "1103 Paulsen" rootstock and phylloxera. In addition, WRKY46 exhibited a higher transcript abundance in "1103 Paulsen" than in "Crimson Seedless", regardless of whether the plants were infected with phylloxera. Furthermore, the enhanced expression of VvWRKY46 significantly attenuated phylloxera attack and delayed nymph development of composite grape plants. In summary, we demonstrated that WRKY46 plays a role in the SA-mediated defense-regulatory network by directly binding to the downstream structural gene VvCHIB. The phylloxera-responsive gene WRKY46 was identified, which could improve the understanding of the basic mechanism of grapevine in response to phylloxera.

Designing Heterogeneous Catalysts for Renewable Catalysis Applications Using Metal Oxide Deposition.

Heterogeneous catalysis has long been a workhorse for the chemical industry and will likely play a key role in the emerging area of renewable chemistry. However, renewable molecule streams pose unique challenges for heterogeneous catalysis due to their high oxygen content, frequent low volatility and the near constant presence of water. These constraints can often lead to the need for catalyst operation in harsh liquid phase conditions, which has compounded traditional catalyst deactivation issues. Oxygenated molecules are also frequently more reactive than petroleum-derived molecules, which creates a need for highly selective catalysts. Synthetic control over the nanostructured environment of catalytic active sites could facilitate the creation of both more stable and selective catalysts. In this review, we discuss the use of metal oxide deposition as an emerging strategy that can be used to synthesize and/or modify heterogeneous catalysts to introduce tailored nanostructures. Several important applications are reviewed, including the synthesis of high surface area mesoporous metal oxides, the enhancement of catalyst stability, and the improvement of catalyst selectivity.

Slowing the Kinetics of Alumina Sol-Gel Chemistry for Controlled Catalyst Overcoating and Improved Catalyst Stability and Selectivity.

Catalyst overcoating is an emerging approach to engineer surface functionalities on supported metal catalyst and improve catalyst selectivity and durability. Alumina deposition on high surface area material by sol-gel chemistry is traditionally difficult to control due to the fast hydrolysis kinetics of aluminum-alkoxide precursors. Here, sol-gel chemistry methods are adapted to slow down these kinetics and deposit nanometer-scale alumina overcoats. The alumina overcoats are comparable in conformality and thickness control to overcoats prepared by atomic layer deposition even on high surface area substrates. The strategy relies on regulating the hydrolysis/condensation kinetics of Al(s BuO)3 by either adding a chelating agent or using nonhydrolytic sol-gel chemistry. These two approaches produce overcoats with similar chemical properties but distinct physical textures. With chelation chemistry, a mild method compatible with supported base metal catalysts, a conformal yet porous overcoat leads to a highly sintering-resistant Cu catalyst for liquid-phase furfural hydrogenation. With the nonhydrolytic sol-gel route, a denser Al2 O3 overcoat can be deposited to create a high density of Lewis acid-metal interface sites over Pt on mesoporous silica. The resulting material has a substantially increased hydrodeoxygenation activity for the conversion of lignin-derived 4-propylguaiacol into propylcyclohexane with up to 87% selectivity.

Stimulation of cyclic electron flow around PSI as a response to the combined stress of high light and high temperature in grape leaves.

Changes in cyclic electron flow (CEF) around PSI activity after exposing grape (Vitis vinifera L.) seedling leaves to the combined stress of high temperature (HT) and high light (HL) were investigated. The PSII potential quantum efficiency (Fv/Fm) decreased significantly under exposure to HT, and this decrease was greater when HT was combined with HL, whereas the PSI activity maintained stable. HT enhanced CEF mediated by NAD(P)H dehydrogenase remarkably. Compared with the control leaves, the half-time of P700+ re-reduction decreased during the HT treatment; this decrease was even more pronounced under the combined stress, implying significantly enhanced CEF as a result of the treatment. However, the heat-induced increase in nonphotochemical quenching (NPQ) was greater under HL, accompanied by a greater enhancement in high-energy state quenching. These results suggest that the combined stress of HT and HL resulted in severe PSII photoinhibition, whereas CEF showed plasticity in its response to environmental stress and played an important role in PSII and PSI photoprotection through accelerating generation of the thylakoid proton gradient and the induction of NPQ.

The distribution and species of Ca2+ and subcellular localization of Ca2+ and Ca2+-ATPase in grape leaves of plants treated with fluoroglycofen.

Fluoroglycofen, a post-emergence herbicide used in vineyards to eradicate weeds, has previously been shown to turn grape leaves dark green following its use. Therefore, this study evaluates the relationship of dark green leaves with calcium form and subcellular distribution. To do this, we focused on the Ca2+ distribution and Ca2+-ATPase activity in leaf cells of one-year-old self-rooted Chardonnay grapevines treated with fluoroglycofen. Plants were separated into different treatments when they had seven or eight leaves, and different concentrations of fluoroglycofen were sprayed on the sand. The results showed that all of the soluble calcium content in the grape leaves that were treated with the highest concentration of fluoroglycofen (187.5gaiha-1) increased significantly. Specifically, the water-soluble organic acid calcium, pectate calcium, and calcium oxalate increased by 18.43%, 17.14%, and 31.05%, respectively, in the upper leaves than in the control. The subcellular distribution of Ca2+ in the dark green leaves increased significantly, especially in the cell wall and chloroplast, which increased by 25.54% and 24.10%, respectively. Through the ultrastructure localization of Ca2+ and Ca2+-ATPase contrasted with the control, the extracellular space and chloroplasts in the mesophyll cells of dark green leaves had large calcium pyroantimonate (Ca-PA) deposits. The extracellular space had fewer Ca2+-ATPase precipitation particles, whereas the chloroplasts had more. At the same time, a high concentration of fluoroglycofen decreased Ca2+-ATPase activity in grape leaves, which potentially might be due to disrupted regulation of calcium homeostatic mechanisms inside and outside of cells, resulting in a large number of Ca2+ accumulation in cells. The Ca2+ accumulation not only hindered the various cellular physiological reactions, but also caused leaves to become dark green in color.

Identification of a Novel Alternative Splicing Variant of VvPMA1 in Grape Root under Salinity.

It has been well-demonstrated that the control of plasma membrane H+-ATPase (PM H+-ATPase) activity is important to plant salt tolerance. This study found a significant increase in PM H+-ATPase (PMA) activity in grape root exposed to NaCl. Furthermore, 7 Vitis vinifera PM H+-ATPase genes (VvPMAs) were identified within the grape genome and the expression response of these VvPMAs in grape root under salinity was analyzed. Two VvPMAs (VvPMA1 and VvPMA3) were expressed more strongly in roots than the other five VvPMAs. Moreover, roots exhibited diverse patterns of gene expression of VvPMA1 and VvPMA3 responses to salt stress. Interestingly, two transcripts of VvPMA1, which were created through alternative splicing (AS), were discovered and isolated from salt stressed root. Comparing the two VvPMA1 cDNA sequences (designated VvPMA1α and VvPMA1ß) with the genomic sequence revealed that the second intron was retained in the VvPMA1ß cDNA. This intron retention was predicted to generate a novel VvPMA1 through N-terminal truncation because of a 5'- terminal frame shift. Yeast complementation assays of the two splice variants showed that VvPMA1ß could enhance the ability to complement Saccharomyces cerevisiae deficient in PM H+-ATPase activity. In addition, the expression profiles of VvPMA1α and VvPMA1ß differed under salinity. Our data suggests that through AS, the N-terminal length of VvPMA1 may be regulated to accurately modulate PM H+-ATPase activity of grape root in salt stress.

Induction of cyclic electron flow around photosystem I during heat stress in grape leaves.

Photosystem II (PSII) in plants is susceptible to high temperatures. The cyclic electron flow (CEF) around PSI is thought to protect both PSII and PSI from photodamage. However, the underlying physiological mechanisms of the photosynthetic electron transport process and the role of CEF in grape at high temperatures remain unclear. To investigate this issue, we examined the responses of PSII energy distribution, the P700 redox state and CEF to high temperatures in grape leaves. After exposing 'Cabernet Sauvignon' leaves to various temperatures (25, 30, 35, 40 and 45°C) in the light (600µmol photons m-2s-1) for 4h, the maximum quantum yield of PSII (Fv/Fm) significantly decreased at high temperatures (40 and 45°C), while the maximum photo-oxidizable P700 (Pm) was not affected. As the temperature increased, higher initial rates of increase in post-illumination Chl fluorescence were detected, which were accompanied by an increase in high energy state quenching (qE). The chloroplast NAD(P)H dehydrogenase-dependent CEF (NDH-dependent CEF) activities were different among grape cultivators. 'Gold Finger' with greater susceptibility to photoinhibition, exhibited lower NDH-dependent CEF activities under acute heat stress than a more heat tolerant 'Cabernet Sauvignon'. These results suggest that overclosure of PSII reaction centers at high temperature resulted in the photoinhibition of PSII, while the stimulation of CEF in grape played an important role in the photoprotection of PSII and PSI at high temperatures through contributing to the generation of a proton gradient.

Study of Binding Interaction between Pif80 Protein Fragment and Aragonite.

Pif is a crucial protein for the formation of the nacreous layer in Pinctada fucata. Three non-acidic peptide fragments of the aragonite-binding domain (Pif80) are selected, which contain multiple copies of the repeat sequence DDRK, to study the interaction between non-acidic peptides and aragonite. The polypeptides DDRKDDRKGGK (Pif80-11) and DDRKDDRKGGKDDRKDDRKGGK (Pif80-22) have similar binding affinity to aragonite. Solid-state NMR data indicate that the backbones of Pif80-11 and Pif80-22 peptides bound on aragonite adopt a random-coil conformation. Pif80-11 is a lot more effective than Pif80-22 in promoting the nucleation of aragonite on the substrate of ß-chitin. Our results suggest that the structural arrangement at a protein-mineral interface depends on the surface structure of the mineral substrate and the protein sequence. The side chains of the basic residues, which function as anchors to the aragonite surface, have uniform structures. The role of basic residues as anchors in protein-mineral interaction may play an important role in biomineralization.

[Effects of different salt and alkali stresses on ion distribution in Red globe/Beta grapevines].

The potted Red globe/Beta grapevines were selected to irrigated with NaCl, Na2SO4, NaHCO3, NH4Cl, (NH4)2SO4. Hence, the ions which induced leaf etiolation were screened and the impacts of different salt and alkali on ion distribution in different organs of grapevines were investigated. It was found that NaHCO3 exerted the greatest effects on grapevines, leaf etiolation at 14 days after treatment. By contrast, NaCl and NH4Cl treatments induced leaf etiolation at 28 days after treatment. The Na+ content in all the detected organs were significantly increased under NaHCO3 and NaCl treatment, and Na+ content in root under NaHCO3 treatment was 6.4 times as that in control root. NaHCO3 and NaCl treatments significantly decreased K+ content in the organs with the exception of leaf. NaHCO3 treatment significantly decreased K/Na in different organs, which declined to 0.1 in root. By contrast, NaCl treatment significantly decreased K/Na in the detected organs with exception of stem. Besides, the transport of Ca2+, Mg2+, Fe2+ to aboveground organs was significantly decreased by NaHCO3 and NaCl treatments. K/Na ratio in the detected organs were decreased under NH4Cl, (NH4) 2SO4 and Na2SO4 treatments, especially under NH4 Cl treatment. Taken together, NaHCO3 was the primary factor resulting in leaf etiolation, followed by NaCl and NH4Cl, while (NH4) 2SO4 and Na2SO4 produced impacts.

The phenotype of grape leaves caused by acetochlor or fluoroglycofen, and effects of latter herbicide on grape leaves.

Fluoroglycofen and acetochlor are two different herbicides used in vineyards to eradicate weeds. This present study first characterized the effects of these chemicals on phenotype of grape leaves. Results showed that acetochlor caused the middle- and upper-node grape leaves become yellow at 60th day after treatment, while fluoroglycofen caused the ones became dark green. Then the effects of fluoroglycofen on photosynthetic pigments and chloroplast ultrastructure were characterized. Results showed that fluoroglycofen increased the chlorophyll and carotenoid contents by different extent in different node leaves, while it did not affect the net photosynthesis rate significantly. Chloroplast ultrastructure analysis showed that the gap between thylakoids layers in few chloroplasts of middle-node leaves increased, which was also observed in ones of upper-node leaves; the number and size of chloroplast increased. Analysis on the deformed leaves of grapevines treated with 375 g ai ha(-1) fluoroglycofen showed that the starch grain per cell was much more and larger than that in the same size control leaves; the dark green and yellow parts had more or fewer chloroplast than the control, respectively, but both with more grana per chloroplast and less layers per granum. Chloroplasts went larger and round. Taken together, these results suggested that fluoroglycofen caused the grape leaves become dark green, which might be associated with the changes of chloroplast; the growth inhibition in the second year might be due to accumulation of starch.